CN112830693A

CN112830693A - Optimized magnesium slag-based cementing material and preparation method thereof

Info

Publication number: CN112830693A
Application number: CN202110328279.6A
Authority: CN
Inventors: 刘浪
Original assignee: Xi'an Fuer Lvchuang Mining Technology Co Ltd
Current assignee: Xi'an Fuer Lvchuang Mining Technology Co Ltd
Priority date: 2021-03-27
Filing date: 2021-03-27
Publication date: 2021-05-25
Also published as: CN113929321A; CN113929321B

Abstract

The invention discloses an optimized magnesium slag-based cementing material and a preparation method thereof, wherein the optimized magnesium slag-based cementing material comprises optimized magnesium slag, the optimized magnesium slag is magnesium slag obtained by naturally aging or thermally pouring modified magnesium slag, and the modified magnesium slag is magnesium slag obtained by performing activity retention and stability retention treatment on magnesium slag generated by Pidgeon magnesium smelting; the preparation method of the optimized magnesium slag-based cementing material comprises the steps of obtaining modified magnesium slag in a magnesium smelting plant, and placing the modified magnesium slag in a slag field for natural aging or hot pouring treatment to obtain an optimized magnesium slag raw material; and carrying out coarse crushing and fine crushing pretreatment on the optimized magnesium slag raw material to obtain an optimized magnesium slag material. The invention provides the optimized magnesium slag-based cementing material which can completely replace high-cost cement, greatly reduce the cost of the cementing material, provide a new utilization way for solid waste disposal in two major pillar industries of coal chemical industry and magnesium smelting, and solve the problems of long setting time and low early-middle stage setting strength of the magnesium slag cementing material.

Description

Optimized magnesium slag-based cementing material and preparation method thereof

Technical Field

The invention belongs to the technical field of solid waste recycling, and particularly relates to an optimized magnesium slag-based cementing material and a preparation method thereof.

Background

The magnesium metal and the alloy thereof as 'green engineering materials in the 21 st century' have important positions in the economic development of China. By 2019, the raw magnesium yield in China is 96.9 ten thousand tons, but the magnesium metal production in China mainly adopts the Pidgeon method, 6-8 tons of magnesium slag waste is generated when 1 ton of magnesium is produced, and hot magnesium slag expands and pulverizes in the cooling process to generate a large amount of dust, thereby seriously polluting the local environment. The existing patents all use the unmodified magnesium slag, and the problems of complex magnesium slag activity excitation process, high transportation cost and the like generally exist. Although the pulverization problem of the Chinese patent CN103011472 is solved by optimizing the magnesium slag, how to utilize the resource is urgently needed to be solved.

In the prior art, the magnesium slag disposal mode is mainly landfill, and generally a slag yard is built after anti-seepage treatment by utilizing natural gullies, landfill is carried out, and the surface is reclaimed after landfill; occupies a large amount of land, has the hidden trouble of seriously polluting atmosphere, water source and earth surface ecology, and simultaneously, a large amount of magnesium slag is buried, thus causing great waste of resources.

Cement is the most mature cementing material in technical development and the most used amount in the world today, but the high cost of cement limits its popularization in some industries with low strength requirements or low profit margins, such as filling mining of cheap metal ores and coal filling mining, etc. In order to reduce the cost, the industry uses the industrial waste residues such as fly ash, magnesium slag, gasified slag, steel slag and the like as mixed materials and admixtures to replace part of cement, but still has the problem of high cost.

The magnesium slag contains high MgO, and after the magnesium slag is mixed into cement, high-content unhydrated free MgO, namely unstable components, can remain, and the free MgO gradually hydrates and expands along with the passage of time, so that a solidified body cracks and even falls off, and the strength is obviously reduced.

In order to reduce the cost of cement raw materials, some waste residues are often blended as raw materials.

Chinese patent CN101492260A discloses a magnesium slag portland cement and its manufacturing method, the main ingredients are cement clinker, gypsum, magnesium slag, and its disadvantage is that magnesium slag can only be used as admixture, and can not be completely separated from cement clinker.

Chinese patent CN1715232 discloses a method for producing cement clinker by using waste slag from magnesium smelting, the main ingredients are gypsum, magnesium slag, limestone, clay, iron ore, anthracite and fluorite, but the method requires a cement firing process, has high energy consumption, and has the defect that the content of MgO in the magnesium waste slag is limited to 6-10% of the total weight, and other raw materials are not industrial solid wastes.

Chinese patent CN101417867 discloses a method for manufacturing magnesium silicate slag cement by using magnesium slag, which still uses magnesium slag as admixture to be mixed into cement clinker.

Chinese patent CN103435281A discloses a cement clinker and its preparation process, the main raw materials include limestone, sandstone powder, magnesium slag, fly ash and copper slag, but the patent also needs a cement firing process, and the energy consumption is large.

Chinese patent CN102432206A discloses a chemical excitation magnesium slag-based geopolymer cementing material and a preparation method thereof, wherein magnesium slag and slag which can provide aluminosilicate components are used as raw materials, and a chemical activator sodium silicate is added to prepare the cementing material.

Chinese patent CN110318802A discloses a magnesium slag cementing material and a forming process method thereof, wherein the raw materials comprise water, sodium bicarbonate and magnesium slag, but the magnesium slag cementing material is used for independently binding and forming the magnesium slag, so that the porosity of the material is reduced, and the strength is not high.

Disclosure of Invention

The invention aims to solve the technical problem of providing an optimized magnesium slag-based cementing material and a preparation method thereof, aiming at overcoming the defects in the prior art, wherein the optimized magnesium slag-based cementing material can completely replace high-cost cement, greatly reduce the cost of the cementing material, and provide a new utilization way for solid waste disposal in two major pillar industries of coal chemical industry and magnesium smelting.

In order to solve the technical problems, the invention adopts the technical scheme that: the optimized magnesium slag-based gelling material is characterized by comprising the following raw materials in percentage by weight: optimized magnesium slag 50-90%, fly ash 10-40% and activator 0-20%; the optimized magnesium slag is the magnesium slag obtained by carrying out natural aging or hot pouring treatment on the modified magnesium slag, and the modified magnesium slag is the magnesium slag obtained by carrying out activity retention and stability retention treatment on the magnesium slag generated by smelting magnesium by a Pidgeon process.

The optimized magnesium slag-based cementing material is characterized in that: comprises the following raw materials in percentage by weight: optimized magnesium slag 65-80%, fly ash 15-30% and activator 5-15%.

The invention also discloses a preparation method of the optimized magnesium slag-based cementing material, which is characterized by comprising the following steps of:

step one, obtaining modified magnesium slag in a magnesium smelting plant, and placing the modified magnesium slag in a slag field for natural aging or hot pouring treatment to obtain an optimized magnesium slag raw material; carrying out coarse crushing and fine crushing pretreatment on the optimized magnesium slag raw material to obtain an optimized magnesium slag material;

and step two, mixing the optimized magnesium slag, the fly ash and the activator according to the content designed in advance, and grinding the mixture into the optimized magnesium slag-based cementing material.

The preparation method of the optimized magnesium slag-based cementing material is characterized by comprising the following steps of: in the second step, the specific process of mixing the optimized magnesium slag, the fly ash and the activator according to the content designed in advance and grinding the mixture into the optimized magnesium slag-based cementing material comprises the following steps:

step 201, weighing and optimizing magnesium slag, fly ash and an activator in proportion and mixing; the optimized magnesium slag, the fly ash and the activator comprise the following components in percentage by weight: optimized magnesium slag 50-90%, fly ash 10-40% and activator 0-20%;

and step 202, pouring the mixture into a ball mill for grinding to obtain the optimized magnesium slag-based cementing material.

The preparation method of the optimized magnesium slag-based cementing material is characterized by comprising the following steps of: the second step comprises the process of designing and optimizing the content of the magnesium slag, the fly ash and the activator in advance, and specifically comprises the following steps:

step A1, selecting optimized magnesium slag, fly ash and an activating agent with different weight percentage contents within the optimized magnesium slag, fly ash and activating agent optimized formula range; the optimized magnesium slag, the fly ash and the activating agent are preferably prepared from the following raw materials in percentage by weight: optimized magnesium slag 50-90%, fly ash 10-40% and activator 0-20%;

step A2, inputting optimized magnesium slag, fly ash and activating agent with different weight percentages in combination with different days into a Tensorflow network selected according to a pre-trained optimal ratio to obtain the predicted strength of the optimized magnesium slag-based cementing material;

and A3, selecting the mixture ratio corresponding to the highest strength for 28 days as the optimal mixture ratio, and determining the optimal mixture ratio as the content of the optimized magnesium slag, the fly ash and the activator.

step B1, obtaining the predicted strength parameter of the optimized magnesium slag-based cementing material, and the specific process is as follows:

step B11, selecting optimized magnesium slag, fly ash and activating agent with different weight percentage contents within the optimized magnesium slag, fly ash and activating agent optimized formula range; the optimized magnesium slag, the fly ash and the activating agent are preferably prepared from the following raw materials in percentage by weight: optimized magnesium slag 50-90%, fly ash 10-40% and activator 0-20%;

step B12, inputting the optimized magnesium slag, the fly ash and the activator with different weight percentages in combination with different days into a Tensorflow network selected according to a pre-trained optimal proportion to obtain the predicted strength of the optimized magnesium slag-based cementing material;

step B13, according to the formula

Normalizing the predicted strength of the optimized magnesium slag-based cementing material obtained in the step B12 to obtain a normalized strength value y_1nor(ii) a Wherein, y₁For the predicted intensity of different days under the mixture ratio of the material, min y₁For minimum prediction intensity, max y₁Is the maximum predicted intensity;

and step B2, obtaining economic index parameters of the optimized magnesium slag-based cementing material, and the specific process comprises the following steps:

step B21, respectively setting the unit prices of the optimized magnesium slag, the fly ash and the activator as a₁、a₂、a₃Constructing an economic indicator function as y₂＝a₁x₁+a₂x₂+a₃x₃(ii) a Wherein, y₂Is an economic indicator, x₁Is a coefficient related to the content of the optimized magnesium slag and x₁∈(0.5,0.9)，x₂Is a coefficient related to the content of fly ash and x₂∈(0.1,0.4)，x₃Is a coefficient related to the content of the activator and x₃∈(0,0.2)；

Step B22, according to the economic index function y₂＝a₁x₁+a₂x₂+a₃x₃And x₁、x₂And x₃To solve the maximum value max y of the economic index₂And minimum value min y of economic index₂；

Step B23, according to the formula

Normalizing the economic index obtained in the step B22 to obtain a normalized economic index y_2nor；

Step B3, according to the intensity value y after normalization processing_1norAnd the normalized economic index y_2norConstructing an objective function for determining an optimal ratio based on intensity and economy as

Determining the ratio corresponding to the maximum value of the objective function y as the optimal ratio, and determining the optimal ratio as the content of the optimized magnesium slag, the optimized fly ash and the optimized activator; wherein alpha is₁Is a weight coefficient of intensity, alpha₂Weight coefficient of economic nature, TH₁Is the lowest up-to-standard intensity value of intensity, TH₂Is the highest price threshold acceptable in economic indicators.

The preparation method of the optimized magnesium slag-based cementing material is characterized by comprising the following steps of: the training process of selecting the Tensorflow network according to the optimal proportion is as follows:

step C1, establishing a four-layer Tensorflow network, wherein the input layer comprises 4 nodes, the middle two layers comprise 5 nodes in each layer, and the output layer comprises 1 node; wherein, the 4 nodes of the input layer are respectively the optimized magnesium slag content, the fly ash content, the activator content and the days; 1 node of the output layer is the prediction strength;

step C2, obtaining the strength of the optimized magnesium slag, the fly ash and the activator with different weight percentage contents obtained by a plurality of groups of experiments under different days as sample data;

step C3, normalizing the days in the sample data;

and step C4, training the Tensorflow network established in the step C1 by adopting the sample data after normalization processing, and iterating for multiple times to obtain the trained optimal mixture ratio selection Tensorflow network.

The invention also discloses an optimized magnesium slag-based cementing material which is characterized by comprising the following raw materials in percentage by weight: optimized magnesium slag 5-30%, gasified slag 50-80% and activator 0-20%; the optimized magnesium slag is the magnesium slag obtained by carrying out natural aging or hot pouring treatment on the modified magnesium slag, and the modified magnesium slag is the magnesium slag obtained by carrying out activity retention and stability retention treatment on the magnesium slag generated by smelting magnesium by a Pidgeon process.

The optimized magnesium slag-based cementing material is characterized in that: comprises the following raw materials in percentage by weight: optimized magnesium slag 15-25 wt%, gasified slag 60-70 wt% and activator 5-15 wt%.

secondly, carrying out screening, coarse crushing and fine crushing pretreatment on the coal gasification coarse slag to obtain coal gasification slag;

and step three, mixing the optimized magnesium slag, the gasified slag and the activator according to the content designed in advance, and grinding the mixture into the optimized magnesium slag-based cementing material.

The preparation method of the optimized magnesium slag-based cementing material is characterized by comprising the following steps of: in the third step, the specific process of mixing the optimized magnesium slag, the gasified slag and the activating agent according to the content designed in advance and grinding the mixture into the optimized magnesium slag-based cementing material comprises the following steps:

301, weighing and optimizing the magnesium slag, the gasified slag and the activator in proportion and mixing; the optimized magnesium slag, the gasified slag and the activator comprise the following components in percentage by weight: optimized magnesium slag 5-30%, gasified slag 50-80% and activator 0-20%;

and step 302, pouring the mixture into a ball mill for grinding to obtain the optimized magnesium slag-based cementing material.

The preparation method of the optimized magnesium slag-based cementing material is characterized by comprising the following steps of: the third step comprises the process of designing and optimizing the content of the magnesium slag, the gasified slag and the activator in advance, and specifically comprises the following steps:

step A1, selecting optimized magnesium slag, gasified slag and activating agent with different weight percentage contents in the optimized magnesium slag, gasified slag and activating agent optimized formula range; the optimized magnesium slag, the gasified slag and the activating agent are preferably prepared from the following raw materials in percentage by weight: optimized magnesium slag 5-30%, gasified slag 50-80% and activator 0-20%;

step A2, inputting optimized magnesium slag, gasified slag and activating agent with different weight percentages into a Tensorflow network according to a pre-trained optimal proportion by combining different days to obtain the predicted strength of the optimized magnesium slag-based cementing material;

and A3, selecting the mixture ratio corresponding to the highest strength for 28 days as the optimal mixture ratio, and determining the optimal mixture ratio as the content of the optimized magnesium slag, the gasified slag and the activator.

step B11, selecting optimized magnesium slag, gasified slag and activating agent with different weight percentage contents in the optimized magnesium slag, gasified slag and activating agent optimized formula range; the optimized magnesium slag, the gasified slag and the activating agent are preferably prepared from the following raw materials in percentage by weight: optimized magnesium slag 5-30%, gasified slag 50-80% and activator 0-20%;

step B12, inputting the optimized magnesium slag, the gasified slag and the activator with different weight percentages in combination with different days into a Tensorflow network selected according to a pre-trained optimal proportion to obtain the predicted strength of the optimized magnesium slag-based cementing material;

step B13, according to the formula

Normalizing the predicted strength of the optimized magnesium slag-based cementing material obtained in the step B12 to obtain a normalized strength value y'_1nor(ii) a Wherein, y'₁Is the predicted intensity in min y 'for different days at the mix ratio of the material'₁Is the minimum predicted intensity, max y'₁Is the maximum predicted intensity;

step B21, respectively setting the unit prices of the optimized magnesium slag, the gasified slag and the activator as a'₁、a′₂、a′₃Constructing an economic indicator function of y'₂＝a′₁x′₁+a′₂x′₂+a′₃x′₃(ii) a Wherein, y'₂Is an economic indicator of x'₁Is a coefficient and x 'related to the content of the optimized magnesium slag'₁∈(0.05,0.3)，x′₂Is a coefficient related to the content of gasified slag and x'₂∈(0.5,0.8)，x′₃Is a coefficient related to the content of activator and x'₃∈(0,0.2)；

Step B22, according to an economic indicator function y'₂＝a′₁x′₁+a′₂x′₂+a′₃x′₃And x'₁、x′₂And x'₃Obtaining the maximum value max y 'of the economic indicator'₂And minimum value of economic indicator min y'₂；

Step B23, according to the formula

Normalizing the economic indicator obtained in the step B22 to obtain a normalized economic indicator y'_2nor；

Step B3, obtaining the normalized intensity value y'_1norAnd the economic indicator y 'after normalization treatment'_2norConstructing an objective function for determining an optimal ratio based on intensity and economy as

Determining the corresponding ratio when the value of the objective function y' is maximum as the optimal ratio, and determining the optimal ratio as the content of the optimized magnesium slag, the gasified slag and the activator; wherein, alpha'₁Is a weight coefficient of intensity, alpha'₂Is an economic weight coefficient, TH'₁Is the lowest up-to-standard strength value of strength, TH'₂Is the highest price threshold acceptable in economic indicators.

step C1, establishing a four-layer Tensorflow network, wherein the input layer comprises 4 nodes, the middle two layers comprise 5 nodes in each layer, and the output layer comprises 1 node; wherein, the 4 nodes of the input layer respectively optimize the content of magnesium slag, the content of gasified slag, the content of an activating agent and the number of days; 1 node of the output layer is the prediction strength;

step C2, obtaining the strength of the optimized magnesium slag, the gasified slag and the activator with different weight percentage contents obtained by a plurality of groups of experiments under different days as sample data;

step C3, normalizing the days in the sample data;

The invention also discloses an optimized magnesium slag-based cementing material which is characterized by comprising the following raw materials in percentage by weight: 85-100% of waste residue mixture and 0-15% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: optimized magnesium slag 5-30%, gasified slag 60-90% and fly ash 5-30%; the optimized magnesium slag is the magnesium slag obtained by carrying out natural aging or hot pouring treatment on the modified magnesium slag, and the modified magnesium slag is the magnesium slag obtained by carrying out activity retention and stability retention treatment on the magnesium slag generated by smelting magnesium by a Pidgeon process.

The optimized magnesium slag-based cementing material is characterized in that: comprises the following raw materials in percentage by weight: the waste residue mixture comprises the following raw materials in percentage by weight: optimized magnesium slag 10-22 wt%, gasified slag 65-80 wt% and flyash 10-22 wt%.

and step three, mixing the optimized magnesium slag, the gasified slag and the fly ash according to the content designed in advance to form a waste slag mixture, adding an activating agent, and grinding the mixture into the optimized magnesium slag-based cementing material.

The preparation method of the magnesium-cinder-based novel cementing material is characterized by comprising the following steps of: the concrete process of mixing the gasified slag, the optimized magnesium slag and the fly ash, adding the activating agent and grinding into the magnesium-coal slag-based novel cementing material in the third step is as follows:

301, weighing gasified slag, optimized magnesium slag and fly ash according to a proportion, and mixing to form a waste slag mixture; the coal gasification coarse slag, the optimized magnesium slag and the fly ash comprise the following components in percentage by weight: optimized magnesium slag 5-30%, gasified slag 60-90% and fly ash 5-30%;

step 302, weighing and mixing the waste residue mixture and the activating agent according to a proportion; the weight percentage content of the waste residue mixture and the activating agent is as follows: 85-100% of waste residue mixture and 0-15% of activating agent;

and step 303, pouring the mixture into a ball mill for grinding to obtain the optimized magnesium slag-based cementing material.

The preparation method of the magnesium-cinder-based novel cementing material is characterized by comprising the following steps of: the third step comprises the process of designing and optimizing the content of the magnesium slag, the gasified slag, the fly ash and the activator in advance, and specifically comprises the following steps:

step A1, selecting optimized magnesium slag, gasified slag, fly ash and an activator with different weight percentage contents within the optimized magnesium slag, gasified slag, fly ash and activator optimized formula range; the optimized magnesium slag, the gasified slag, the fly ash and the activator are preferably prepared from the following raw materials in percentage by weight: 85-100% of waste residue mixture and 0-15% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: optimized magnesium slag 5-30%, gasified slag 60-90% and fly ash 5-30%;

step A2, inputting optimized magnesium slag, gasified slag, fly ash and an activator with different weight percentages in combination with different days into a Tensorflow network selected according to a pre-trained optimal proportion to obtain the predicted strength of the optimized magnesium slag-based cementing material;

and A3, selecting the mixture ratio corresponding to the highest strength for 28 days as the optimal mixture ratio, and determining the optimal mixture ratio as the content of the optimized magnesium slag, the gasified slag, the fly ash and the activator.

step B11, selecting optimized magnesium slag, gasified slag, fly ash and an activating agent with different weight percentage contents within the optimized magnesium slag, gasified slag, fly ash and activating agent optimized formula range; the optimized magnesium slag, the gasified slag, the fly ash and the activator are preferably prepared from the following raw materials in percentage by weight: 85-100% of waste residue mixture and 0-15% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: optimized magnesium slag 5-30%, gasified slag 60-90% and fly ash 5-30%;

step B12, inputting the optimized magnesium slag, the gasified slag, the fly ash and the activator with different weight percentages in combination with different days into a Tensorflow network selected according to a pre-trained optimal proportion to obtain the predicted strength of the optimized magnesium slag-based cementing material;

step B13, according to the formula

Normalizing the predicted strength of the optimized magnesium slag-based cementing material obtained in the step B12 to obtain a normalized strength value y ″_1nor(ii) a Wherein, y ″)₁The predicted intensity of the material in different days, min y ″, is₁For minimum prediction intensity, max y ″)₁Is the maximum predicted intensity;

step B21, setting the unit prices of the optimized magnesium slag, the gasified slag, the fly ash and the activator as a ″, respectively₁、a″₂、a″₃、a″₄Constructing an economic indicator function as y ″)₂＝a″₁x″₁+a″₂x″₂+a″₃x″₃+a″₄x″₄(ii) a Wherein, y ″)₂Is an economic indicator, x ″)₁Is a coefficient related to the content of the optimized magnesium slag and x ″)₁∈(0.05,0.3)，x″₂Is a coefficient related to the content of gasified slag and x'₂∈(0.6,0.9)，x″₃Is prepared from coal ashX 'to'₃∈(0.05,0.3)，x″₄Is a coefficient related to the content of activator and x'₄∈(0,0.15)；

Step B22, according to the economic index function y ″)₂＝a″₁x″₁+a″₂x″₂+a″₃x″₃+a″₄x″₄And x ″)₁、x″₂、x″₃And x ″)₄The maximum value max y of the economic index is solved₂And the minimum value min y of the economic indicator₂；

Step B23, according to the formula

Normalizing the economic indicator obtained in the step B22 to obtain a normalized economic indicator y ″_2nor；

Step B3, according to the intensity value y' after normalization processing_1norAnd the economic index y' after normalization processing_2norConstructing an objective function for determining an optimal ratio based on intensity and economy as

Determining the ratio corresponding to the maximum value of the objective function y' as the optimal ratio, and determining the optimal ratio as the content of the optimized magnesium slag, the gasified slag, the fly ash and the activator; wherein, α ″)₁Weight coefficient of intensity, alpha ″)₂Is an economic weight coefficient, TH ″)₁Is the lowest standard strength value of strength, TH₂Is the highest price threshold acceptable in economic indicators.

step C1, establishing a four-layer Tensorflow network, wherein the input layer comprises 5 nodes, the middle layer comprises two layers, each layer comprises 5 nodes, and the output layer comprises 1 node; wherein, the 5 nodes of the input layer respectively optimize the content of magnesium slag, the content of gasified slag, the content of fly ash, the content of an activator and the number of days; 1 node of the output layer is the prediction strength;

step C2, obtaining the strength of the optimized magnesium slag, the gasified slag, the fly ash and the activator with different weight percentage contents obtained by a plurality of groups of experiments under different days as sample data;

step C3, normalizing the days in the sample data;

The optimized magnesium slag-based cementing material is characterized in that: the method for performing activity retention and stability retention treatment on magnesium slag generated by Pidgeon magnesium smelting adopts a method for refining crude magnesium ingots by using modified magnesium smelting pellets to generate modified magnesium slag, wherein the modified magnesium smelting pellets comprise the following raw materials in percentage by weight: 81 to 82.8 percent of calcined dolomite, 15 to 16.6 percent of ferrosilicon, 1.25 to 2.71 percent of fluorite and 0.23 to 0.29 percent of ferroboron; the ferroboron alloy comprises the following elements in percentage by weight: 16 to 20.5 percent of B, 0.5 to 1.0 percent of C, 1.5 to 2.5 percent of Si, 0.05 to 0.5 percent of Al and the balance of Fe.

The optimized magnesium slag-based cementing material is characterized in that: the method for producing the modified magnesium slag by using the modified magnesium smelting pellets to smelt the crude magnesium ingot comprises the following steps:

d1, according to the weight percentage of each raw material in the modified magnesium-smelting pellets, sending the raw materials into a mill, uniformly mixing and finely grinding the raw materials, then passing through a 100-mesh sieve, and pressing undersize materials to obtain the modified magnesium-smelting pellets;

and D2, loading the modified magnesium smelting pellets in the step D1 into a reduction tank, reducing for 7-8 h under the conditions that the vacuum degree is 5-10 Pa and the temperature is 1200-1220 ℃, opening the reduction tank after the reduction is finished, taking out a crude magnesium ingot, and removing magnesium slag in the reduction tank to obtain blocky modified magnesium slag.

The optimized magnesium slag-based cementing material is characterized in that: the method for performing activity retention and stability retention treatment on magnesium slag generated by Pidgeon magnesium smelting adopts a method for refining crude magnesium ingots by using modified magnesium smelting pellets to generate modified magnesium slag, wherein the modified magnesium smelting pellets comprise the following raw materials in percentage by weight: 12 to 18 percent of ferrosilicon, 0.5 to 3 percent of fluorite, 0.3 to 3.1 percent of boric acid or borax, and the balance of calcined dolomite.

e1, according to the weight percentage of each raw material in the modified magnesium-smelting pellets, sending the raw materials into a mill, uniformly mixing and finely grinding the raw materials, then passing through a 100-mesh sieve, and pressing undersize materials to obtain the modified magnesium-smelting pellets;

and E2, loading the modified magnesium smelting pellets in the step E2 into a reduction tank, reducing for 6-10 h under the conditions that the vacuum degree is 5-20 Pa and the temperature is 1150-1250 ℃, opening the reduction tank after the reduction is finished, taking out a crude magnesium ingot, and removing magnesium slag in the reduction tank to obtain blocky modified magnesium slag.

The optimized magnesium slag-based cementing material is characterized in that: the activating agent is one or more of gypsum, anhydrous sodium sulphate, calcium hydroxide, lime, soda, baking soda, heavy calcium, sodium silicate, polymeric salt, sodium chloride and caustic soda; the gypsum is natural gypsum, phosphogypsum, fluorgypsum or industrial desulfurization gypsum.

The preparation method of the optimized magnesium slag-based cementing material is characterized by comprising the following steps of: in the step one, the pretreatment of coarse crushing and fine crushing of the optimized magnesium slag raw material is carried out, and the specific process of obtaining the optimized magnesium slag material is as follows:

step 101, coarse crushing: coarsely crushing blocky optimized magnesium slag in the optimized magnesium slag raw material by using a jaw crusher;

step 102, fine crushing: and (4) finely crushing the coarsely crushed optimized magnesium slag by using a double-roll crusher to obtain an optimized magnesium slag material.

The preparation method of the optimized magnesium slag-based cementing material is characterized by comprising the following steps of: when the mixture is poured into a ball mill for grinding, the mixture is ground until the particle size is less than 40 mu m and the specific surface area range is 300m²/kg～350m²Up to/kg.

The preparation method of the optimized magnesium slag-based cementing material is characterized by comprising the following steps of: in the second step, the coal gasification slag is subjected to screening, coarse crushing and fine crushing pretreatment, and the specific process of obtaining the coal gasification slag material is as follows:

step 201, screening: screening the coal gasification coarse slag by using a vibrating screen to obtain a predetermined grain size meeting the requirement;

step 202, coarse crushing: coarsely crushing the screened gasified slag by using a jaw crusher;

step 203, fine crushing: and (4) finely crushing the screened gasified slag by using a double-roller crusher.

The preparation method of the optimized magnesium slag-based cementing material is characterized by comprising the following steps of: the specific method for predetermining the particle size meeting the requirement in step 201 is as follows:

step 2011, screening the coal gasification coarse slag by a multistage vibrating screen according to the mesh number, wherein the screening is multistage; the coal gasification coarse slag is coal gasification slag raw slag generated after the coal chemical industry enterprise produces synthesis gas;

step 2012, measuring the quality and carbon content of the coal gasification coarse slag with different particle size ranges;

step 2013, using the mass as weight and according to a formula

Calculating the weighted carbon content omega of the coal gasification coarse slag, determining the particle size range of the coal gasification coarse slag meeting the carbon content requirement according to the national standard GB/T1596-2017 that the ignition loss of the fly ash used for cement or concrete is less than or equal to 8 percent, and determining the particle size range as the particle size meeting the requirement; wherein j is the stage number corresponding to the maximum grain diameter meeting the requirement of carbon content, i is a natural number from 1 to j, and m_iIs the quality of i-th-stage coal gasification coarse slag, w_iThe carbon content of the i-th-stage coal gasification coarse slag is shown.

Compared with the prior art, the invention has the following advantages:

1. according to the invention, various novel cementing materials are prepared by utilizing the mutual excitation effects between the fly ash and the optimized magnesium slag, between the gasified slag and the optimized magnesium slag, and between the fly ash, the gasified slag and the optimized magnesium slag, so that the hidden troubles that later-stage concreting bodies crack and fall off and the strength is obviously reduced due to the independent mixing of the magnesium slag are solved, high-cost cement can be completely replaced, and the cost of the cementing materials is greatly reduced.

2. The invention utilizes fly ash and optimized magnesium slag, or gasified slag and optimized magnesium slag, or fly ash, gasified slag and optimized magnesium slag as main materials, and a small amount of activating agent is matched to prepare a plurality of optimized magnesium slag-based cementing materials, the novel cementing material preparation method takes industrial solid wastes as main materials, utilizes the mutual excitation effect between fly ash and optimized magnesium slag, between gasified slag and optimized magnesium slag, and between fly ash, gasified slag and optimized magnesium slag, realizes the cementing effect of cement-like materials, eliminates the influence of unstable components (free MgO), and can completely replace cement; in addition, the adopted activator is a common non-toxic and harmless chemical reagent with low price and little addition amount, so the optimized magnesium slag-based cementing material has low cost, can greatly reduce the cost by replacing cement, and simultaneously provides a new utilization way for solid waste disposal in the coal chemical industry and the magnesium smelting industry.

3. According to the invention, the activator is used for inducing the mutual excitation effect between the fly ash and the optimized magnesium slag, between the gasified slag and the optimized magnesium slag, and between the fly ash, the gasified slag and the optimized magnesium slag, so that the hydration speed and the consolidation strength of the mixture are improved, and the problems of long setting time and low consolidation strength in the middle and early stages of the magnesium slag cementing material are solved.

4. The novel cementing material realizes the resource utilization of solid wastes of three industries, namely fly ash, coal gasification slag and optimized magnesium slag, and solves the environmental problems of land occupation, air pollution, underground water, surface ecology and the like caused by the treatment of the solid wastes generated in the modern coal chemical industry and magnesium smelting industry in the traditional landfill mode.

5. The preparation method of the novel cementing material takes three industrial solid wastes of the fly ash, the gasified slag and the optimized magnesium slag as main materials, utilizes the characteristic of higher content of alkaline active substances in the optimized magnesium slag to excite the activity of volcanic ash substances in the fly ash, and also utilizes the characteristic of higher content of aluminosilicate in the fly ash to neutralize the alkaline substances in the optimized magnesium slag to form a chain reaction, thereby eliminating the influence of unstable components (free MgO), having high consolidation strength and being capable of completely replacing cement.

6. The optimized preparation method of the magnesium slag-based cementing material realizes resource utilization of waste slag in the modern coal chemical industry and the magnesium smelting industry, and promotes sustainable development of the modern coal chemical industry and the magnesium smelting industry; the optimized magnesium slag-based cementing material has low cost, can be applied to the industries of construction, mine filling, road building, ceramic manufacturing and the like, greatly reduces the cost of the cementing material (replacing cement), eliminates the pollution of waste slag stacking to the environment, and has excellent economic benefit and social benefit.

The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.

Drawings

FIG. 1 is a photomicrograph of a sample of magnesium slag produced in comparative example 1;

FIG. 2 is a photomicrograph of a sample of magnesium slag produced in example 1 of the present invention;

FIG. 3 is an XRD diffraction pattern of a magnesium slag sample produced in example 1 of the present invention and comparative example 1;

FIG. 4 is a bar graph of compressive strength values of magnesium slag cement made from magnesium slag obtained in example 1 of the present invention and magnesium slag cement made from magnesium slag obtained in comparative example 1;

FIG. 5 is a flowchart of a method for preparing an optimized magnesium slag-based cementitious material in example 20 of the present invention;

FIG. 6 is a flowchart of a method for preparing an optimized magnesium slag-based cementitious material in example 34 of the present invention.

Detailed Description

The formulation of the modified magnesium-smelting pellets used in the present invention for producing modified magnesium slag and the method for producing modified magnesium slag will be described below with reference to examples 1 to 7; the formulation of the first optimized magnesium slag-based cementitious material according to the invention is illustrated in examples 8 to 19; example 20 illustrates a first process for producing a first optimized magnesium slag-based cementitious material according to the present invention; example 21 illustrates a second method of producing the first optimized magnesium slag-based cementitious material according to the present invention; example 22 illustrates a third process for preparing the first optimized magnesium slag-based cementitious material according to the present invention; the formulation of the second optimized magnesium slag-based cementitious material of the present invention is illustrated by examples 23-33; example 34 illustrates a first process for producing a second optimized magnesium slag-based cementitious material according to the present invention; example 35 illustrates a second process for the preparation of a second optimized magnesium slag-based cementitious material according to the present invention; a third process for producing the second optimized magnesium slag-based cementitious material according to the invention is described in example 36; the formulation of the third optimized magnesium slag-based cementitious material of the present invention is illustrated by examples 37-47; example 48 illustrates a third process for the production of an optimized magnesium slag-based cementitious material according to the present invention; example 49 illustrates a second method for preparing a third optimized magnesium slag-based cementitious material according to the present invention; example 50 illustrates a third method of producing a third optimized magnesium slag-based cementitious material according to the present invention;

example 1

The modified magnesium-smelting pellet of the embodiment comprises the following raw materials in percentage by weight: calcined dolomite (CaO/MgO molar ratio close to 1) 81%, ferrosilicon (Si content about 75%) 16.5%, and fluorite (CaF in fluorite)₂Content not less than 95%) 2.25%, ferroboron alloy 0.25%; the weight percentages of all elements in the ferroboron alloy are as follows: b20%, C0.5%, Si 1.5%, Al 0.5%, S<0.01％，P<0.1% and the balance Fe; the granularity of the ferroboron alloy is not more than 5 mm. (refer to GB/T5682-2015 to select ferroboron with the grade of FeB2 0C0.5B.)

The method for producing the modified magnesium slag by adopting the modified magnesium smelting pellets to smelt the crude magnesium ingot comprises the following steps:

d1, according to the weight percentage of each raw material in the modified magnesium-smelting pellets, sending the raw materials into a mill, uniformly mixing and finely milling, then passing through a 100-mesh sieve, adding the undersize into a ball press, and pressing to obtain the beta-C in the stable magnesium slag₂S, modifying the magnesium-smelting pellets;

d2, loading the modified magnesium smelting pellets in the step D1 into a reduction tank, reducing for 7 hours under the conditions that the vacuum degree is 8Pa and the temperature is 1210 ℃, opening the tank after the reduction is finished, taking out a potassium-sodium catcher and a magnesium crystallizer, and removing the potassium-sodium catcher and the magnesium crystallizer from the magnesium crystallizerTaking out the coarse magnesium ingot, raking out magnesium slag in the reduction tank, and cooling the raked-out magnesium slag to room temperature in a magnesium slag hopper to obtain blocky modified magnesium slag subjected to activity maintaining and stability maintaining treatment; after the cover of the reduction tank is opened, air enters the tank, a plurality of micropores exist in the reduced pellets, oxygen in the air can immediately enter the pellets through the micropores, and boron in ferroboron is oxidized into B at the high temperature of about 1000 DEG C₂O₃. B formed by oxidation₂O₃Is very active at high temperature, can quickly contact nearby dicalcium orthosilicate and enter crystal lattices of the dicalcium orthosilicate, and then stabilizes beta-C through chemical reaction₂S, which makes it unable to convert to gamma-C during cooling₂S, such that beta-C is₂S becomes a main crystal phase at room temperature and exists in the waste pellets after magnesium smelting. Due to the oxidation of boron element into B₂O₃And B₂O₃Stabilising beta-C₂The chemical reaction of S is only carried out in the waste magnesium-smelting pellets, and all the production operations after opening the reduction tank, including the work of taking out the potassium-sodium catcher, the magnesium crystallizer, the heat insulation plate and the magnesium slag can be normally carried out without being influenced.

Comparative example 1

The comparative example adopts the traditional Pidgeon process to produce the magnesium pellets, and the weight percentages of the raw materials in the pellets are as follows: 81% forged steel (CaO/MgO molar ratio close to 1), 16.5% ferrosilicon (Si content about 75%), and fluorite (CaF in fluorite)₂Content not less than 95%) 2.5%. A crude magnesium ingot was prepared according to the magnesium smelting method of example 1 and magnesium slag was tapped from the reduction vessel and cooled to room temperature in a magnesium slag hopper.

The magnesium slag of comparative example 1 was mostly pulverized as observed after cooling the tapped magnesium slag to room temperature, as shown in fig. 1. The magnesium slag of the embodiment 1 is massive, and the size of most of the magnesium slag is similar to that before the magnesium smelting of the pellets, which is shown in figure 2. XRD analysis was performed on samples of magnesium slag from the two pellet smelting groups of example 1 and comparative example 1, and the results are shown in FIG. 3. As can be seen from the PMS spectrum of FIG. 3(b), the main mineral phase in the magnesium slag produced in comparative example 1 was γ -C₂S, this analysis confirmed C₂The volume expansion caused by the beta-gamma phase transformation of S (dicalcium orthosilicate) is the magnesium slag shown in FIG. 1The main cause of dusting. As can be seen from the MMS chart in FIG. 3(a), the main mineral phase in the magnesium slag produced in example 1 is β -C₂And S. Such magnesium slag is not pulverized and substantially maintains its original lump shape (see fig. 2), and thus does not generate dust pollution during transportation and homogenization. By beta-C₂The S is a main mineral phase at room temperature, so that the activity of the magnesium slag is greatly improved, and the modified and optimized magnesium slag can be widely applied to cement or concrete, thereby powerfully promoting the energy conservation, emission reduction and sustainable development of metal magnesium and building material production enterprises.

The stability and the compressive strength values of different ages of the magnesium slag cement prepared by using the magnesium slag obtained in the example 1 of the invention and the magnesium slag cement prepared by using the magnesium slag obtained in the comparative example 1 are respectively measured according to a standard method in GB75-2007, wherein the weight percentage of the cement and the magnesium slag in the magnesium slag cement is 65 percent, and the weight percentage of the magnesium slag in the magnesium slag cement is 35 percent. The stability tests of the two magnesium slag cements by the test cake method both obtain qualified results. The results of the compressive strength tests are shown in figure 4, which shows that the 3-day compressive strength values of 2 groups of magnesium slag cements are basically the same, the 28-90-day compressive strength of the magnesium slag cement in example 1 is higher than that of the magnesium slag cement in comparative example 1, especially in two ages of 60 days and 90 days, the compressive strength value of the magnesium slag cement in example 1 is greatly improved compared with that of the magnesium slag cement in comparative example 1, and the fact that the magnesium smelting pellets added with ferroboron can produce modified magnesium slag with high activity as a high-quality admixture for preparing the optimized magnesium slag-based cementing material is confirmed.

Example 2

The modified magnesium-smelting pellet of the embodiment comprises the following raw materials in percentage by weight: calcined dolomite (CaO/MgO molar ratio close to 1) 81.2%, ferrosilicon (Si content about 75%) 16.6%, and fluorite (CaF in fluorite)₂Content not less than 95%) 1.94%, ferroboron alloy 0.26%; the weight percentages of all elements in the ferroboron alloy are as follows: 18% of B, 0.5% of C, 1.5% of Si, 0.5% of Al, and S<0.01％，P<0.1% and the balance Fe; the granularity of the ferroboron alloy is not more than 5 mm. (refer to GB/T5682-2015 to select ferroboron with the grade of FeB2 0C0.5B.)

d2, loading the modified magnesium smelting pellets in the step D1 into a reduction tank, reducing for 8 hours under the conditions that the vacuum degree is 10Pa and the temperature is 1200 ℃, opening the tank after the reduction is finished, taking out a potassium-sodium catcher and a magnesium crystallizer, taking out a coarse magnesium ingot from the magnesium crystallizer, raking out magnesium slag in the reduction tank, and cooling the raked-out magnesium slag to room temperature in a magnesium slag bucket to obtain blocky modified magnesium slag subjected to activity retention and stability retention treatment; after the cover of the reduction tank is opened, air enters the tank, a plurality of micropores exist in the reduced pellets, oxygen in the air can immediately enter the pellets through the micropores, and boron in ferroboron is oxidized into B at the high temperature of about 1000 DEG C₂O₃. B formed by oxidation₂O₃Is very active at high temperature, can quickly contact nearby dicalcium orthosilicate and enter crystal lattices of the dicalcium orthosilicate, and then stabilizes beta-C through chemical reaction₂S, which makes it unable to convert to gamma-C during cooling₂S, such that beta-C is₂S becomes a main crystal phase at room temperature and exists in the waste pellets after magnesium smelting. Due to the oxidation of boron element into B₂O₃And B₂O₃Stabilising beta-C₂The chemical reaction of S is only carried out in the waste magnesium-smelting pellets, and all the production operations after opening the reduction tank, including the work of taking out the potassium-sodium catcher, the magnesium crystallizer, the heat insulation plate and the magnesium slag can be normally carried out without being influenced.

Comparative example 2

The magnesium smelting pellets adopted in the comparative example comprise the following raw materials in percentage by weight: calcined dolomite (CaO/MgO molar ratio close to 1) 81.2%, ferrosilicon (Si content about 75%) 16.6%, and fluorite (CaF in fluorite)₂Content of not less than 95%) 0.5%, anhydrous sodium tetraborate (Na)₂B₄O₇)1.7 percent; a crude magnesium ingot was prepared and a magnesium slag was tapped according to the magnesium smelting method of example 2, in whichAnd cooling the magnesium slag hopper to room temperature.

Example 3

The modified magnesium-smelting pellet of the embodiment comprises the following raw materials in percentage by weight: calcined dolomite (CaO/MgO molar ratio is close to 1) 82%, ferrosilicon (Si content is about 75%) 15%, fluorite (CaF in fluorite)₂Content not less than 95%) 2.71%, ferroboron alloy 0.29%; the weight percentages of all elements in the ferroboron alloy are as follows: b16%, C1.0%, Si 2.5%, Al 0.5%, S<0.01％，P<0.1% and the balance Fe; the granularity of the ferroboron alloy is not more than 5 mm. (refer to GB/T5682-2015 for selection of ferroboron with the trademark of FeB 16C1.0.)

d2, loading the modified magnesium smelting pellets in the step D1 into a reduction tank, reducing for 7.5h under the conditions that the vacuum degree is 9Pa and the temperature is 1215 ℃, opening the tank after the reduction is finished, taking out a potassium-sodium catcher and a magnesium crystallizer, taking out a coarse magnesium ingot from the magnesium crystallizer, raking out magnesium slag in the reduction tank, and cooling the raked-out magnesium slag to room temperature in a magnesium slag bucket to obtain blocky modified magnesium slag subjected to activity maintaining and stability maintaining treatment; after the cover of the reduction tank is opened, air enters the tank, a plurality of micropores exist in the reduced pellets, oxygen in the air can immediately enter the pellets through the micropores, and boron in ferroboron is oxidized into B at the high temperature of about 1000 DEG C₂O₃. B formed by oxidation₂O₃Is very active at high temperature, can quickly contact nearby dicalcium orthosilicate and enter crystal lattices of the dicalcium orthosilicate, and then stabilizes beta-C through chemical reaction₂S, which makes it unable to convert to gamma-C during cooling₂S, such that beta-C is₂S becomes a main crystal phase at room temperature and exists in the waste pellets after magnesium smelting. Due to the oxidation of boron element into B₂O₃And B₂O₃Stabilising beta-C₂The chemical reaction of S is only carried out in the waste magnesium-smelting pellets, and all the production operations after opening the reduction tank, including the work of taking out the potassium-sodium catcher, the magnesium crystallizer, the heat insulation plate and the magnesium slag can be normally carried out without being influenced.

Comparative example 3

The magnesium smelting pellets adopted in the comparative example comprise the following raw materials in percentage by weight: calcined dolomite (CaO/MgO molar ratio is close to 1) 82%, ferrosilicon (Si content is about 75%) 15%, fluorite (CaF in fluorite)₂Content not less than 95%) 1.1%, sodium borate (Na)₂B₄O₇)1.9 percent; a crude magnesium ingot was prepared and a magnesium slag was tapped according to the magnesium smelting method of example 3, and cooled to room temperature in a magnesium slag hopper.

Example 4

The modified magnesium-smelting pellet of the embodiment comprises the following raw materials in percentage by weight: calcined dolomite (CaO/MgO molar ratio close to 1) 82.8%, ferrosilicon (Si content about 75%) 15.72%, and fluorite (CaF in fluorite)₂Content not less than 95%) 1.25% and ferroboron alloy 0.23%; the weight percentages of all elements in the ferroboron alloy are as follows: 20.5% of B, 0.5% of C, 1.5% of Si, 0.05% of Al, and S<0.01％，P<0.1% and the balance Fe; the granularity of the ferroboron alloy is not more than 5 mm. (refer to GB/T5682-2015 to select ferroboron with the grade of FeB2 0C0.5A.)

d2, loading the modified magnesium smelting pellets in the step D1 into a reduction tank, reducing for 7.9h under the conditions that the vacuum degree is 5Pa and the temperature is 1220 ℃, opening the tank after the reduction is finished, taking out a potassium-sodium catcher and a magnesium crystallizer, taking out a coarse magnesium ingot from the magnesium crystallizer, removing magnesium slag in the reduction tank, cooling the removed magnesium slag to room temperature in a magnesium slag bucket to obtain the magnesium slag with activity preservationMaintaining and stabilizing the treated blocky modified magnesium slag; after the cover of the reduction tank is opened, air enters the tank, a plurality of micropores exist in the reduced pellets, oxygen in the air can immediately enter the pellets through the micropores, and boron in ferroboron is oxidized into B at the high temperature of about 1000 DEG C₂O₃. B formed by oxidation₂O₃Is very active at high temperature, can quickly contact nearby dicalcium orthosilicate and enter crystal lattices of the dicalcium orthosilicate, and then stabilizes beta-C through chemical reaction₂S, which makes it unable to convert to gamma-C during cooling₂S, such that beta-C is₂S becomes a main crystal phase at room temperature and exists in the waste pellets after magnesium smelting. Due to the oxidation of boron element into B₂O₃And B₂O₃Stabilising beta-C₂The chemical reaction of S is only carried out in the waste magnesium-smelting pellets, and all the production operations after opening the reduction tank, including the work of taking out the potassium-sodium catcher, the magnesium crystallizer, the heat insulation plate and the magnesium slag can be normally carried out without being influenced.

Measured beta-C in the Stable magnesium slag of examples 1-3 of the present invention₂The modified magnesium-smelting pellets of S and the pellets of comparative examples 1 to 3 were subjected to magnesium-smelting to obtain a feed magnesium ratio (feed magnesium ratio: the weight of the magnesium-smelting pellets/the weight of crude magnesium obtained), and the magnesium slags obtained in examples 1 to 3 and comparative examples 1 to 3 were subjected to chemical analysis to obtain analysis values of the magnesium oxide content in these magnesium slag samples. The results are shown in Table 1. (the comparison parameter values used in the following discussion are the average of more than 3 measured or analyzed values under the same conditions.)

TABLE 1 analysis value of MgO (%)

Magnesium smelting pellet	Ratio of material to magnesium	MgO in the magnesium slag	Additive for smelting magnesium pellets
				Example 1	5.92	5.21	Ferroboron gold
Comparative example 1	6.23	7.06	Is free of
				Example 2	6.05	5.93	Ferroboron gold
Comparative example 2	6.31	6.51	Anhydrous sodium tetraborate
				Example 3	6.12	5.65	Ferroboron gold
Comparative example 3	6.28	6.83	Boric acid

As can be seen from the table, the magnesium ratio (5.92-6.12) of the materials for smelting magnesium by using the modified magnesium-smelting pellets of 3 examples is lower than that obtained after magnesium smelting by using the pellets of the comparative exampleThe ratio of the magnesium to the raw materials is (6.23-6.31). The magnesium oxide content (5.21% to 5.92%) in the magnesium slag samples discharged from the magnesium pelletizing in examples 1 to 3 was also low. The comparison of these parameters shows that ferroboron as additive for smelting magnesium pellets and other materials containing Na which is harmful to Pidgeon magnesium smelting₂Compared with the additive of crystal water, the additive of O can obtain higher MgO reduction rate and Si utilization rate, thereby being capable of helping the Pidgeon magnesium production to reduce cost and improve efficiency, save energy and reduce emission; in addition, the blocky modified magnesium slag obtained by performing activity maintaining and stability maintaining treatment on the magnesium slag generated by smelting magnesium by the Pidgeon process can be better used for preparing an optimized magnesium slag-based cementing material.

Example 5

The modified magnesium-smelting pellet of the embodiment comprises the following raw materials in percentage by weight: 84.7 percent of forged steel (the molar ratio of CaO/MgO is close to 1), 12 percent of ferrosilicon (the Si content is about 75 percent), 3 percent of fluorite (the content of CaF2 in fluorite is not less than 95 percent) and 0.3 percent of boric acid or borax.

and E2, loading the modified magnesium smelting pellets in the step E2 into a reduction tank, reducing for 8 hours under the conditions that the vacuum degree is 12.5Pa and the temperature is 1200 ℃, opening the reduction tank after the reduction is finished, taking out a crude magnesium ingot, and removing magnesium slag in the reduction tank to obtain blocky modified magnesium slag.

Example 6

The modified magnesium-smelting pellet of the embodiment comprises the following raw materials in percentage by weight: 78.4 percent of forged steel (the molar ratio of CaO/MgO is close to 1), 18 percent of ferrosilicon (the Si content is about 75 percent), 0.5 percent of fluorite (the content of CaF2 in fluorite is not less than 95 percent) and 3.1 percent of boric acid or borax.

and E2, loading the modified magnesium smelting pellets in the step E2 into a reduction tank, reducing for 10 hours under the conditions that the vacuum degree is 5Pa and the temperature is 1150 ℃, opening the reduction tank after the reduction is finished, taking out a crude magnesium ingot, and removing magnesium slag in the reduction tank to obtain blocky modified magnesium slag.

Example 7

The modified magnesium-smelting pellet of the embodiment comprises the following raw materials in percentage by weight: 81.55% of forged white (the molar ratio of CaO/MgO is close to 1), 15% of ferrosilicon (the Si content is about 75%), 1.75% of fluorite (the content of CaF2 in fluorite is not less than 95%) and 1.7% of boric acid or borax.

and E2, loading the modified magnesium smelting pellets in the E2 into a reduction tank, reducing for 6 hours under the conditions that the vacuum degree is 20Pa and the temperature is 1250 ℃, opening the reduction tank after the reduction is finished, taking out a crude magnesium ingot, and removing magnesium slag in the reduction tank to obtain blocky modified magnesium slag.

Example 8

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: optimized magnesium slag 90%, fly ash 10% and activator 0%; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

The modified magnesium slag typically has 5% or more of free MgO, because the free MgO in the modified magnesium slag hydrates slowly if not everywhereThen directly used for preparing optimized magnesium slag-based cementing materials, after forming a cemented filling body or a concrete member, Mg (OH) is generated along with the slow hydration of MgO₂The volume of the cemented filling body or the concrete member expands, so that the cemented filling body or the concrete member cracks and falls off, the strength of the cemented filling body or the concrete member is obviously reduced, and potential production safety hazards exist; the problems can be effectively avoided by performing natural aging or hot pouring treatment on the modified magnesium slag to form the optimized magnesium slag and preparing the optimized magnesium slag-based cementing material from the optimized magnesium slag.

In this embodiment, the activator is gypsum, and the gypsum is natural gypsum, phosphogypsum, fluorgypsum or industrial desulfurization gypsum.

Example 9

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: 70% of optimized magnesium slag, 20% of fly ash and 10% of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is anhydrous sodium sulphate (mirabilite).

Example 10

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: optimized magnesium slag 50%, fly ash 30% and activator 20%; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is calcium hydroxide.

Example 11

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: 55% of optimized magnesium slag, 40% of fly ash and 5% of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is lime.

Example 12

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: 60% of optimized magnesium slag, 25% of fly ash and 15% of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this example, the activator is soda.

Example 13

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: 80% of optimized magnesium slag, 15% of fly ash and 5% of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this example, the activator is baking soda.

Example 14

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: 72.5 percent of optimized magnesium slag, 17.5 percent of fly ash and 10 percent of activator; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this example, the activator is triple superphosphate.

Example 15

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: optimizing 65% of magnesium slag, 20% of fly ash and 15% of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this example, the activator is sodium silicate.

Example 16

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: optimizing 65% of magnesium slag, 30% of fly ash and 5% of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is a polymeric salt.

Example 17

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: 65% of optimized magnesium slag, 22.5% of fly ash and 12.5% of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is a polymeric salt.

Example 18

In this embodiment, the activator is sodium chloride.

Example 19

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: optimizing 75% of magnesium slag, 25% of fly ash and 10% of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is caustic soda.

In the above examples 8 to 19, the activator may be any combination of two or more of gypsum, anhydrous sodium sulphate (mirabilite), calcium hydroxide, lime, soda, baking soda, heavy calcium, sodium silicate, polymeric salt, sodium chloride and caustic soda.

In specific implementation, the proportion of each component for forming the optimized magnesium slag-based cementing material can be adjusted according to cost, fluidity, strength, environment and the like.

In order to verify the performance of the optimized magnesium slag-based cementing materials in the examples 8 to 19, standard samples were prepared according to the ingredients in the examples, and the formula composition is shown in table 2;

table 2 formula table of optimized magnesium slag-based cement in examples 8 to 19

Curing the optimized magnesium slag-based cementing material in a standard curing box for 28 days (curing temperature is 20 ℃ and humidity is 95%), and performing compressive strength test on the optimized magnesium slag-based cementing material according to a related method specified in cement mortar strength test method GB/T17671-1999 to obtain Table 3;

table 3 table of performance test results of the optimized magnesium slag-based cement materials in examples 8 to 19

Example 20

As shown in fig. 5, a method for preparing an optimized magnesium slag-based cementitious material in any one of embodiments 8 to 19 includes the following steps:

in the step one, the pretreatment of coarse crushing and fine crushing of the optimized magnesium slag raw material is carried out, and the specific process of obtaining the optimized magnesium slag material is as follows:

In specific implementation, the selection of the crusher is not limited to the two types, and a suitable crusher is selected by considering factors such as the particle size of the raw material, the strength, the grindability index, the humidity, the viscosity and the like.

In the second step, the specific process of mixing the optimized magnesium slag, the fly ash and the activator according to the content designed in advance and grinding the mixture into the optimized magnesium slag-based cementing material comprises the following steps:

step 201, weighing and optimizing magnesium slag, fly ash and an activator in proportion and mixing; the optimized magnesium slag, the fly ash and the activator comprise the following components in percentage by weight: optimized magnesium slag 50-90%, fly ash 10-40% and activator 0-20% (specifically, the formula of any one of the optimized magnesium slag-based cementing materials in embodiments 8-19);

When the mixture is poured into a ball mill for grinding, the mixture is ground until the particle size is less than 40 mu m and the specific surface area range is 300m²/kg～350m²Up to/kg.

Example 21

An optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: optimized magnesium slag 50-90%, fly ash 10-40% and activator 0-20%; the optimized magnesium slag is the magnesium slag obtained by carrying out natural aging or hot pouring treatment on the modified magnesium slag, and the modified magnesium slag is the magnesium slag obtained by carrying out activity retention and stability retention treatment on the magnesium slag generated by smelting magnesium by a Pidgeon process.

A preparation method of the optimized magnesium slag-based cementing material comprises the following steps:

Wherein, the process of designing and optimizing the content of the magnesium slag, the fly ash and the activator in advance comprises the following steps:

in specific implementation, the different days comprise 3 days, 7 days, 14 days, 28 days, 56 days, 90 days and 120 days, the optimized magnesium slag, the fly ash and the activator in different weight percentages are in the optimized formula range of the optimized magnesium slag, the fly ash and the activator, each step size is 0.01, and all the possible situations are changed circularly.

step 201, weighing and optimizing magnesium slag, fly ash and an activator in proportion and mixing;

The training process of selecting the Tensorflow network according to the optimal proportion is as follows:

step C1, establishing a four-layer Tensorflow network, wherein the input layer comprises 4 nodes, the middle two layers comprise 5 nodes in each layer, and the output layer comprises 1 node; wherein 4 nodes of the input layer respectively comprise the content (50-90%) of optimized magnesium slag, the content (10-40%) of fly ash, the content (0-20%) of an activator and days (3 days, 7 days, 14 days, 28 days, 56 days, 90 days and 120 days); 1 node of the output layer is the prediction strength;

in specific implementation, the number of the sample data is 200-1000 groups;

step C3, normalizing the days in the sample data;

the number of days is mapped between 0 and 1, and in the specific implementation, the number of days is respectively 3 days, 7 days, 14 days, 28 days, 56 days, 90 days and 120 days, 3 days are mapped to be 0, and 120 days are mapped to be 1;

The pseudo code is as follows:

derived in pseudo-code

Namely the optimal proportion.

Example 22

the training process of selecting the Tensorflow network according to the optimal ratio is the same as that of the embodiment 21.

Step B13, according to the formula

Step B23, according to the formula

Example 23

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: 5% of optimized magnesium slag, 80% of coal gasification slag and 15% of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

The modified magnesium slag generally has 5 percent or more of free MgO, and because the free MgO in the modified magnesium slag is slowly hydrated and can be directly used as a cementing material for preparing and optimizing magnesium slag base if not processed, after a cemented filling body or a concrete member is constructed, Mg (OH) is generated along with the slow hydration of the MgO₂The volume of the cemented filling body or the concrete member expands, so that the cemented filling body or the concrete member cracks and falls off, the strength of the cemented filling body or the concrete member is obviously reduced, and potential production safety hazards exist; the problems can be effectively avoided by performing natural aging or hot pouring treatment on the modified magnesium slag to form the optimized magnesium slag and preparing the optimized magnesium slag-based cementing material from the optimized magnesium slag.

In this embodiment, the activator is gypsum.

Example 24

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: 30% of optimized magnesium slag, 50% of gasified slag and 20% of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is anhydrous sodium sulphate (mirabilite).

Example 25

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: 17.5 percent of optimized magnesium slag, 65.5 percent of gasified slag and 7 percent of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is calcium hydroxide.

Example 26

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: optimized magnesium slag 20%, gasified slag 80% and activator 0%; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is lime.

Example 27

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: optimized magnesium slag 12.5%, gasified slag 67.5% and activator 10%; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this example, the activator is soda.

Example 28

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: optimizing 15% of magnesium slag, 70% of gasified slag and 15% of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this example, the activator is baking soda.

Example 29

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: 25% of optimized magnesium slag, 60% of coal gasification slag and 15% of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this example, the activator is triple superphosphate.

Example 30

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: 25% of optimized magnesium slag, 62.5% of coal gasification slag and 12.5% of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this example, the activator is sodium silicate.

Example 31

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: optimized magnesium slag 20%, gasified slag 65.5% and activator 14.5%; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is a polymeric salt.

Example 32

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: 25% of optimized magnesium slag, 70% of coal gasification slag and 5% of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is sodium chloride.

Example 33

The optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: optimizing 22% of magnesium slag, 68% of coal gasification slag and 10% of activating agent; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is caustic soda.

In the above examples 23 to 33, the activator may be any combination of two or more of gypsum, anhydrous sodium sulphate (mirabilite), calcium hydroxide, lime, soda, baking soda, heavy calcium, sodium silicate, polymeric salt, sodium chloride and caustic soda.

In order to verify the performance of the optimized magnesium slag-based cementing materials in the examples 23 to 33, standard samples were prepared according to the ingredients in the examples, and the composition of the ingredients is shown in table 4;

table 4 formulation table of optimized magnesium slag-based cement in examples 23 to 33

Curing the optimized magnesium slag-based cementing material in a standard curing box for 28 days (curing temperature is 20 ℃ and humidity is 95%), and performing compressive strength test on the optimized magnesium slag-based cementing material according to a related method specified in cement mortar strength test method GB/T17671-1999 to obtain Table 5;

TABLE 5 Performance test results of optimized magnesium slag-based gelling materials in examples 23 to 33

Example 34

As shown in fig. 6, a method for preparing an optimized magnesium slag-based cementitious material in any one of examples 23 to 33 includes the following steps:

in this embodiment, the pretreatment of coarse crushing and fine crushing on the optimized magnesium slag raw material in the step one to obtain the optimized magnesium slag material specifically comprises the following steps:

in this embodiment, the pretreatment of screening, coarse crushing and fine crushing of the coal gasification slag in the second step to obtain the coal gasification slag comprises the following specific processes:

in this embodiment, the specific method for determining the particle size meeting the requirement in step 201 in advance includes:

in the embodiment, a multistage vibrating screen is adopted to screen the coal gasification coarse slag according to the mesh number, the screen is 10 grades, and the 10 grades are respectively smaller than 8 meshes, 8 meshes to 10 meshes, 10 meshes to 14 meshes, 14 meshes to 18 meshes, 18 meshes to 24 meshes, 24 meshes to 35 meshes, 35 meshes to 50 meshes, 50 meshes to 120 meshes, 120 meshes to 200 meshes and larger than 200 meshes;

in this example, the coal gasification coarse slag with a particle size of less than 8 meshes calculated by the total amount of 1000g of the sample is m1(m1 is 253.1g), and the carbon content is w1(w1 is 0.37%); the coal gasification coarse slag with 8 meshes to 10 meshes has the mass of m2(m2 is 39.6g), and the carbon content is w2(w2 is 0.81%); the coal gasification coarse slag with 10 meshes to 14 meshes has the mass of m3(m3 is 82.5g), and the carbon content is w3(w3 is 2.18%); the coal gasification coarse slag with 14 meshes to 18 meshes is m4(m4 is 46.8g), the carbon content is w4(w4 is 6.25%), the coal gasification coarse slag with 18 meshes to 24 meshes is m5(m5 is 96.4g), and the carbon content is w5(w5 is 12.88%); the coal gasification coarse slag with 24 meshes to 35 meshes is m6(m6 is 147.4g), the carbon content is w6(w6 is 26.49%), the coal gasification coarse slag with 35 meshes to 50 meshes is m7(m7 is 164.2g), and the carbon content is w7(w7 is 24.48%); the coal gasification coarse slag with 50 meshes to 120 meshes has the mass of m8(m8 is 113.9g), the carbon content of w8(w8 is 34.46%), the coal gasification coarse slag with 120 meshes to 200 meshes has the mass of m9(m9 is 34.3g), and the carbon content of w9(w9 is 17.55%); the coal gasification coarse slag with the grain size of more than 200 meshes has the mass of m10(m10 is 21.8g), and the carbon content is w10(w10 is 20.68%); the results of measuring the mass and carbon content of the coal gasification coarse slag with different particle size ranges are shown in table 6;

TABLE 6 table of the results of measuring the quality and carbon content of the coal gasification coarse slag having different particle size ranges

Step 2013, using the mass as weight and according to a formula

Calculating the weighted carbon content omega of the coal gasification coarse slag, determining the particle size range of the coal gasification coarse slag meeting the requirement of the carbon content according to the 'loss on ignition of fly ash for cement or concrete is less than or equal to 8%' in national standard GB/T1596-2017 (fly ash for cement and concrete), and determining the particle size range as the particle size meeting the requirement; wherein j is the stage number corresponding to the maximum grain diameter meeting the requirement of carbon content, i is a natural number from 1 to j, and m_iIs the quality of i-th-stage coal gasification coarse slag, w_iThe carbon content of the i-th-stage coal gasification coarse slag is shown.

In the embodiment, the grain size range of the coal gasification coarse slag meeting the carbon content requirement is determined to be that the mesh number is less than 24 meshes (-the carbon content of 24 meshes is 3.54%, and the carbon content of 35 meshes of coal gasification coarse slag is 8.63%).

The specific calculation process is as follows:

-carbon content of 24 mesh gasified slag:

-carbon content of 35 mesh gasified slag:

In the embodiment, the specific process of mixing the optimized magnesium slag, the gasified slag and the activator and grinding the mixture into the optimized magnesium slag-based cementing material according to the content designed in advance in the third step is as follows:

301, weighing and optimizing the magnesium slag, the gasified slag and the activator in proportion and mixing; the optimized magnesium slag, the gasified slag and the activator comprise the following components in percentage by weight: 5-30% of optimized magnesium slag, 50-80% of gasified slag and 0-20% of activator (specifically, the formula of the optimized magnesium slag-based cementing material in any one of embodiments 23-33);

Example 35

An optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: optimized magnesium slag 5-30%, gasified slag 50-80% and activator 0-20%; the optimized magnesium slag is the magnesium slag obtained by carrying out natural aging or hot pouring treatment on the modified magnesium slag, and the modified magnesium slag is the magnesium slag obtained by carrying out activity retention and stability retention treatment on the magnesium slag generated by smelting magnesium by a Pidgeon process.

in this embodiment, the specific process of screening, coarse crushing and fine crushing the coal gasification slag in the second step to obtain the coal gasification slag charge is the same as that in embodiment 34.

in specific implementation, the different days comprise 3 days, 7 days, 14 days, 28 days, 56 days, 90 days and 120 days, the optimized magnesium slag, the gasified slag and the activator with different weight percentage contents are in the optimized formula range of the optimized magnesium slag, the gasified slag and the activator, each step length is 0.01, and all possible situations are changed circularly.

step C1, establishing a four-layer Tensorflow network, wherein the input layer comprises 4 nodes, the middle two layers comprise 5 nodes in each layer, and the output layer comprises 1 node; wherein 4 nodes of the input layer respectively comprise the content of optimized magnesium slag (5-30%), the content of gasified slag (50-80%), the content of an activator (0-20%) and days (3 days, 7 days, 14 days, 28 days, 56 days, 90 days and 120 days); 1 node of the output layer is the prediction strength;

in specific implementation, the number of the sample data is 200-1000 groups;

step C3, normalizing the days in the sample data;

The pseudo code is as follows:

derived in pseudo-code

Namely the optimal proportion.

Example 36

Step B13, according to the formula

step B21, respectively setting the unit prices of the optimized magnesium slag, the gasified slag and the activator as a'₁、a′₂、a′₃Constructing an economic indicator function of y'₂＝a′₁x′₁+a′₂x′₂+a′₃x′₃(ii) a Wherein, y'₂Is an economic indicator of x'₁Is a coefficient and x 'related to the content of the optimized magnesium slag'₁∈(0.05,0.3)，x′₂Is a coefficient related to the content of gasified slag andx′₂∈(0.5,0.8)，x′₃is a coefficient related to the content of activator and x'₃∈(0,0.2)；

Step B23, according to the formula

Example 37

The magnesium-cinder-based novel cementing material comprises the following raw materials in percentage by weight: 85% of waste residue mixture and 15% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: 5% of optimized magnesium slag, 90% of gasified slag and 5% of fly ash; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

Example 38

The magnesium-cinder-based novel cementing material comprises the following raw materials in percentage by weight: 100% of waste residue mixture and 0% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: 30% of optimized magnesium slag, 60% of gasified slag and 10% of fly ash; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is anhydrous sodium sulphate (mirabilite).

Example 39

The magnesium-cinder-based novel cementing material comprises the following raw materials in percentage by weight: 92.5% of waste residue mixture and 7.5% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: optimized magnesium slag 17.5%, gasified slag 75.5% and fly ash 7%; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is calcium hydroxide.

Example 40

The magnesium-cinder-based novel cementing material comprises the following raw materials in percentage by weight: 87% of waste residue mixture and 13% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: optimizing 7% of magnesium slag, 63% of gasified slag and 30% of fly ash; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is lime.

EXAMPLE 41

The magnesium-cinder-based novel cementing material comprises the following raw materials in percentage by weight: 88.5 percent of waste residue mixture and 11.5 percent of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: optimized magnesium slag 12.5%, gasified slag 70% and fly ash 17.5%; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this example, the activator is soda.

Example 42

The magnesium-cinder-based novel cementing material comprises the following raw materials in percentage by weight: 90% of waste residue mixture and 10% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: optimizing 13% of magnesium slag, 65% of gasified slag and 22% of fly ash; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this example, the activator is baking soda.

Example 43

The magnesium-cinder-based novel cementing material comprises the following raw materials in percentage by weight: 97% of waste residue mixture and 3% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: optimizing 22% of magnesium slag, 68% of gasified slag and 10% of fly ash; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this example, the activator is triple superphosphate.

Example 44

The magnesium-cinder-based novel cementing material comprises the following raw materials in percentage by weight: 95% of waste residue mixture and 5% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: optimizing 16% of magnesium slag, 72.5% of gasified slag and 11.5% of fly ash; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this example, the activator is sodium silicate.

Example 45

The magnesium-cinder-based novel cementing material comprises the following raw materials in percentage by weight: 91% of waste residue mixture and 9% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: optimizing 10% of magnesium slag, 80% of gasified slag and 10% of fly ash; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is a polymeric salt.

Example 46

The magnesium-cinder-based novel cementing material comprises the following raw materials in percentage by weight: 88% of waste residue mixture and 12% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: optimizing 19% of magnesium slag, 65% of gasified slag and 16% of fly ash; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is sodium chloride.

Example 47

The magnesium-cinder-based novel cementing material comprises the following raw materials in percentage by weight: 88% of waste residue mixture and 12% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: optimizing 18% of magnesium slag, 67% of gasified slag and 15% of fly ash; the optimized magnesium slag is magnesium slag obtained by performing natural aging or hot pouring treatment on modified magnesium slag, the modified magnesium slag is produced by using the modified magnesium smelting pellets in any one of the embodiments 1 to 7 to produce crude magnesium ingots, and the modified magnesium slag is produced by performing activity maintaining and stability maintaining treatment on magnesium slag produced by smelting magnesium by a Pidgeon process.

In this embodiment, the activator is caustic soda.

In the above examples 37 to 47, the activator may be any combination of two or more of gypsum, anhydrous sodium sulphate (mirabilite), calcium hydroxide, lime, soda, baking soda, heavy calcium, sodium silicate, polymeric salt, sodium chloride and caustic soda.

In order to verify the performance of the optimized magnesium slag-based cementing material in each of examples 37 to 47, standard samples were prepared according to the ingredients in each example, and cured in a standard curing box for 120 days (curing temperature of 20 ℃ and humidity of 95%), and the compressive strength of the optimized magnesium slag-based cementing material was tested according to the relevant method specified in cement mortar strength test method GB/T17671-1999, to obtain table 7;

table 7 table of performance test results of optimized magnesium slag-based cement materials in examples 37 to 47

Example 48

As shown in fig. 6, a preparation method of the optimized magnesium slag-based cementing material comprises the following steps:

Step 2013, using the mass as weight and according to a formula

Gas countingWeighting the carbon content omega of the coarse gasification slag, determining the particle size range of the coarse gasification slag meeting the requirement of the carbon content according to the national standard GB/T1596-2017 (fly ash used in cement and concrete) 'the loss on ignition of the fly ash used in cement or concrete is less than or equal to 8%', and determining the particle size range as the particle size meeting the requirement; wherein j is the stage number corresponding to the maximum grain diameter meeting the requirement of carbon content, i is a natural number from 1 to j, and m_iIs the quality of i-th-stage coal gasification coarse slag, w_iThe carbon content of the i-th-stage coal gasification coarse slag is shown.

The specific calculation process is as follows:

-carbon content of 24 mesh gasified slag:

-carbon content of 35 mesh gasified slag:

In the embodiment, the concrete process of mixing the gasified slag, the optimized magnesium slag and the fly ash, adding the activator, and grinding into the magnesium-coal slag-based novel cementing material in the third step is as follows:

in specific implementation, the proportion can be adjusted according to cost, fluidity, strength and environment;

In this embodiment, when the mixture is poured into a ball mill for grinding, the mixture is ground until the particle size is less than 40 μm and the specific surface area is 300m²/kg～350m²Up to/kg.

Example 49

An optimized magnesium slag-based gelling material comprises the following raw materials in percentage by weight: 85-100% of waste residue mixture and 0-15% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: optimized magnesium slag 5-30%, gasified slag 60-90% and fly ash 5-30%; the optimized magnesium slag is the magnesium slag obtained by carrying out natural aging or hot pouring treatment on the modified magnesium slag, and the modified magnesium slag is the magnesium slag obtained by carrying out activity retention and stability retention treatment on the magnesium slag generated by smelting magnesium by a Pidgeon process.

in this embodiment, the specific process of screening, coarse crushing and fine crushing the coal gasification slag in the second step to obtain the coal gasification slag charge is the same as that in embodiment 48.

in specific implementation, the different days comprise 3 days, 7 days, 14 days, 28 days, 56 days, 90 days and 120 days, the optimized magnesium slag, the gasified slag, the fly ash and the activator in different weight percentage contents are in the optimized formula range of the optimized magnesium slag, the gasified slag, the fly ash and the activator, each step length is 0.01, and all possible situations are changed circularly.

step C1, establishing a four-layer Tensorflow network, wherein the input layer comprises 5 nodes, the middle layer comprises two layers, each layer comprises 5 nodes, and the output layer comprises 1 node; wherein, the 5 nodes of the input layer are respectively the optimized magnesium slag content, the gasified slag content, the fly ash content, the activator content and the days (3 days, 7 days, 14 days, 28 days, 56 days, 90 days and 120 days); 1 node of the output layer is the prediction strength;

in specific implementation, the optimized magnesium slag, the gasified slag, the fly ash and the activator are contained in the following weight percentage: 85-100% of waste residue mixture and 0-15% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: optimized magnesium slag 5-30%, gasified slag 60-90% and fly ash 5-30%;

in specific implementation, the number of the sample data is 200-1000 groups;

step C3, normalizing the days in the sample data;

Example 50

The pseudo code is as follows:

derived in pseudo-code

Namely the optimal proportion.

Step B13, according to the formula

step B21, setting the unit prices of the optimized magnesium slag, the gasified slag, the fly ash and the activator as a ″, respectively₁、a″₂、a″₃、a″₄Constructing an economic indicator function as y ″)₂＝a″₁x″₁+a″₂x″₂+a″₃x″₃+a″₄x″₄(ii) a Wherein, y ″)₂Is an economic indicator, x ″)₁Is a coefficient related to the content of the optimized magnesium slag and x ″)₁∈(0.05,0.3)，x″₂Is a coefficient related to the content of gasified slag and x'₂∈(0.6,0.9)，x″₃Is a coefficient related to the content of fly ash and x'₃∈(0.05,0.3)，x″₄Is a coefficient related to the content of activator and x'₄∈(0,0.15)；

Step B23, according to the formula

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and all simple modifications, changes and equivalent structural changes made to the above embodiment according to the technical spirit of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. The optimized magnesium slag-based gelling material is characterized by comprising the following raw materials in percentage by weight: optimized magnesium slag 50-90%, fly ash 10-40% and activator 0-20%; the optimized magnesium slag is the magnesium slag obtained by carrying out natural aging or hot pouring treatment on the modified magnesium slag, and the modified magnesium slag is the magnesium slag obtained by carrying out activity retention and stability retention treatment on the magnesium slag generated by smelting magnesium by a Pidgeon process.

2. The optimized magnesium slag-based cementitious material of claim 1, wherein: comprises the following raw materials in percentage by weight: optimized magnesium slag 65-80%, fly ash 15-30% and activator 5-15%.

3. A method for preparing an optimized magnesium slag-based cementitious material according to claim 1, characterised in that it comprises the following steps:

4. The preparation method of the optimized magnesium slag-based cementing material according to claim 3, is characterized in that: in the second step, the specific process of mixing the optimized magnesium slag, the fly ash and the activator according to the content designed in advance and grinding the mixture into the optimized magnesium slag-based cementing material comprises the following steps:

5. The preparation method of the optimized magnesium slag-based cementing material according to claim 3, is characterized in that: the second step comprises the process of designing and optimizing the content of the magnesium slag, the fly ash and the activator in advance, and specifically comprises the following steps:

6. The preparation method of the optimized magnesium slag-based cementing material according to claim 3, is characterized in that: the second step comprises the process of designing and optimizing the content of the magnesium slag, the fly ash and the activator in advance, and specifically comprises the following steps:

step B13, rootAccording to the formula

Normalizing the predicted strength of the optimized magnesium slag-based cementing material obtained in the step B12 to obtain a normalized strength value y_1nor(ii) a Wherein, y₁For the predicted intensity of different days under the mixture ratio of the material, miny₁For minimum predicted intensity, maxy₁Is the maximum predicted intensity;

Step B22, according to the economic index function y₂＝a₁x₁+a₂x₂+a₃x₃And x₁、x₂And x₃To solve the maximum value maxy of the economic index₂And minimum value miny of economic index₂；

Step B23, according to the formula

7. The method for preparing the optimized magnesium slag-based cementing material according to the claim 5 or 6, which is characterized in that: the training process of selecting the Tensorflow network according to the optimal proportion is as follows:

step C3, normalizing the days in the sample data;

8. The optimized magnesium slag-based gelling material is characterized by comprising the following raw materials in percentage by weight: optimized magnesium slag 5-30%, gasified slag 50-80% and activator 0-20%; the optimized magnesium slag is the magnesium slag obtained by carrying out natural aging or hot pouring treatment on the modified magnesium slag, and the modified magnesium slag is the magnesium slag obtained by carrying out activity retention and stability retention treatment on the magnesium slag generated by smelting magnesium by a Pidgeon process.

9. The optimized magnesium slag-based cementitious material of claim 8, wherein: comprises the following raw materials in percentage by weight: optimized magnesium slag 15-25 wt%, gasified slag 60-70 wt% and activator 5-15 wt%.

10. A method of producing an optimised magnesium slag-based cementitious material according to claim 8, characterised in that it includes the steps of:

11. The method for preparing the optimized magnesium slag-based cementing material according to claim 10, is characterized in that: in the third step, the specific process of mixing the optimized magnesium slag, the gasified slag and the activating agent according to the content designed in advance and grinding the mixture into the optimized magnesium slag-based cementing material comprises the following steps:

12. The method for preparing the optimized magnesium slag-based cementing material according to claim 10, is characterized in that: the third step comprises the process of designing and optimizing the content of the magnesium slag, the gasified slag and the activator in advance, and specifically comprises the following steps:

13. The method for preparing the optimized magnesium slag-based cementing material according to claim 10, is characterized in that: the third step comprises the process of designing and optimizing the content of the magnesium slag, the gasified slag and the activator in advance, and specifically comprises the following steps:

step B13, according to the formula

Normalizing the predicted strength of the optimized magnesium slag-based cementing material obtained in the step B12,obtaining a normalized intensity value y'_1nor(ii) a Wherein, y'₁Is the predicted intensity in min y 'for different days at the mix ratio of the material'₁Is the minimum predicted intensity, max y'₁Is the maximum predicted intensity;

Step B23, according to the formula

An objective functionThe corresponding ratio is determined as the optimal ratio when the value of y' is maximum, and the optimal ratio is determined as the content of the optimized magnesium slag, the gasified slag and the activator; wherein, alpha'₁Is a weight coefficient of intensity, alpha'₂Is an economic weight coefficient, TH'₁Is the lowest up-to-standard strength value of strength, TH'₂Is the highest price threshold acceptable in economic indicators.

14. The method for preparing an optimized magnesium slag-based cementitious material according to claim 12 or 13, characterized in that: the training process of selecting the Tensorflow network according to the optimal proportion is as follows:

step C3, normalizing the days in the sample data;

15. The optimized magnesium slag-based gelling material is characterized by comprising the following raw materials in percentage by weight: 85-100% of waste residue mixture and 0-15% of activating agent; the waste residue mixture comprises the following raw materials in percentage by weight: optimized magnesium slag 5-30%, gasified slag 60-90% and fly ash 5-30%; the optimized magnesium slag is the magnesium slag obtained by carrying out natural aging or hot pouring treatment on the modified magnesium slag, and the modified magnesium slag is the magnesium slag obtained by carrying out activity retention and stability retention treatment on the magnesium slag generated by smelting magnesium by a Pidgeon process.

16. The optimized magnesium slag-based cementitious material of claim 15, wherein: comprises the following raw materials in percentage by weight: the waste residue mixture comprises the following raw materials in percentage by weight: optimized magnesium slag 10-22 wt%, gasified slag 65-80 wt% and flyash 10-22 wt%.

17. A method for preparing an optimized magnesium slag-based cementitious material according to claim 1, characterised in that it comprises the following steps:

18. The method for preparing the magnesium-cinder-based novel cementing material according to claim 17, characterized in that: the concrete process of mixing the gasified slag, the optimized magnesium slag and the fly ash, adding the activating agent and grinding into the magnesium-coal slag-based novel cementing material in the third step is as follows:

19. The method for preparing the magnesium-cinder-based novel cementing material according to claim 17, characterized in that: the third step comprises the process of designing and optimizing the content of the magnesium slag, the gasified slag, the fly ash and the activator in advance, and specifically comprises the following steps:

20. The method for preparing the magnesium-cinder-based novel cementing material according to claim 17, characterized in that: the third step comprises the process of designing and optimizing the content of the magnesium slag, the gasified slag, the fly ash and the activator in advance, and specifically comprises the following steps:

step B13, according to the formula

Step B23, according to the formula

Normalizing the economic index obtained in the step B22 to obtain a normalized economic index y₂″_nor；

21. The method for preparing an optimized magnesium slag-based cementitious material according to claim 19 or 20, characterized in that: the training process of selecting the Tensorflow network according to the optimal proportion is as follows:

step C3, normalizing the days in the sample data;

22. An optimized magnesium slag based cementitious material as claimed in any one of claims 1, 2, 8, 9, 15 and 16, wherein: the method for performing activity retention and stability retention treatment on magnesium slag generated by Pidgeon magnesium smelting adopts a method for refining crude magnesium ingots by using modified magnesium smelting pellets to generate modified magnesium slag, wherein the modified magnesium smelting pellets comprise the following raw materials in percentage by weight: 81 to 82.8 percent of calcined dolomite, 15 to 16.6 percent of ferrosilicon, 1.25 to 2.71 percent of fluorite and 0.23 to 0.29 percent of ferroboron; the ferroboron alloy comprises the following elements in percentage by weight: 16 to 20.5 percent of B, 0.5 to 1.0 percent of C, 1.5 to 2.5 percent of Si, 0.05 to 0.5 percent of Al and the balance of Fe.

23. The optimized magnesium slag-based cementitious material of claim 22, wherein: the method for producing the modified magnesium slag by using the modified magnesium smelting pellets to smelt the crude magnesium ingot comprises the following steps:

24. An optimized magnesium slag based cementitious material as claimed in any one of claims 1, 2, 8, 9, 15 and 16, wherein: the method for performing activity retention and stability retention treatment on magnesium slag generated by Pidgeon magnesium smelting adopts a method for refining crude magnesium ingots by using modified magnesium smelting pellets to generate modified magnesium slag, wherein the modified magnesium smelting pellets comprise the following raw materials in percentage by weight: 12 to 18 percent of ferrosilicon, 0.5 to 3 percent of fluorite, 0.3 to 3.1 percent of boric acid or borax, and the balance of calcined dolomite.

25. The optimized magnesium slag-based cementitious material of claim 24, wherein: the method for producing the modified magnesium slag by using the modified magnesium smelting pellets to smelt the crude magnesium ingot comprises the following steps:

26. An optimized magnesium slag based cementitious material as claimed in any one of claims 1, 2, 8, 9, 15 and 16, wherein: the activating agent is one or more of gypsum, anhydrous sodium sulphate, calcium hydroxide, lime, soda, baking soda, heavy calcium, sodium silicate, polymeric salt, sodium chloride and caustic soda; the gypsum is natural gypsum, phosphogypsum, fluorgypsum or industrial desulfurization gypsum.

27. The method for preparing an optimized magnesium slag-based cementitious material according to claim 3, 10 or 17, characterized in that: in the step one, the pretreatment of coarse crushing and fine crushing of the optimized magnesium slag raw material is carried out, and the specific process of obtaining the optimized magnesium slag material is as follows:

28. The method for preparing an optimized magnesium slag-based cementitious material according to claim 4, 11 or 18, characterized in that: when the mixture is poured into a ball mill for grinding, the mixture is ground until the particle size is less than 40 mu m and the specific surface area range is 300m²/kg～350m²Up to/kg.

29. The method for preparing an optimized magnesium slag-based cementitious material according to claim 10 or 17, characterized in that: in the second step, the coal gasification slag is subjected to screening, coarse crushing and fine crushing pretreatment, and the specific process of obtaining the coal gasification slag material is as follows:

30. The method for preparing the optimized magnesium slag-based cementing material according to claim 29, wherein the method comprises the following steps: the specific method for predetermining the particle size meeting the requirement in step 201 is as follows:

step 2013, using the mass as weight and according to a formula

Calculating the weighted carbon content omega of the coal gasification coarse slag, and determining that the coal gasification coarse slag meets the requirement of containing coal ash for cement or concrete with the ignition loss less than or equal to 8% in the national standard GB/T1596-contained fly ash 2017Determining the grain size range of the coal gasification coarse slag required by the carbon amount as the grain size meeting the requirement; wherein j is the stage number corresponding to the maximum grain diameter meeting the requirement of carbon content, i is a natural number from 1 to j, and m_iIs the quality of i-th-stage coal gasification coarse slag, w_iThe carbon content of the i-th-stage coal gasification coarse slag is shown.