CN113105258A - Method for preparing undoped single coal gangue ceramsite based on moving bed and ceramsite - Google Patents

Method for preparing undoped single coal gangue ceramsite based on moving bed and ceramsite Download PDF

Info

Publication number
CN113105258A
CN113105258A CN202110369692.7A CN202110369692A CN113105258A CN 113105258 A CN113105258 A CN 113105258A CN 202110369692 A CN202110369692 A CN 202110369692A CN 113105258 A CN113105258 A CN 113105258A
Authority
CN
China
Prior art keywords
ceramsite
section
coal gangue
moving bed
cooling
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202110369692.7A
Other languages
Chinese (zh)
Other versions
CN113105258B (en
Inventor
甘敏
邢金鑫
范晓慧
季志云
孙增青
陈许玲
黄晓贤
袁礼顺
郑浩翔
汪国靖
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Central South University
Original Assignee
Central South University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Central South University filed Critical Central South University
Priority to CN202110369692.7A priority Critical patent/CN113105258B/en
Publication of CN113105258A publication Critical patent/CN113105258A/en
Application granted granted Critical
Publication of CN113105258B publication Critical patent/CN113105258B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
    • C04B38/009—Porous or hollow ceramic granular materials, e.g. microballoons
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B33/00—Clay-wares
    • C04B33/02—Preparing or treating the raw materials individually or as batches
    • C04B33/13—Compounding ingredients
    • C04B33/132—Waste materials; Refuse; Residues
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
    • C04B2235/6562—Heating rate
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
    • C04B2235/6567—Treatment time
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
    • C04B2235/74—Physical characteristics
    • C04B2235/77—Density
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
    • C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P40/00—Technologies relating to the processing of minerals
    • Y02P40/60—Production of ceramic materials or ceramic elements, e.g. substitution of clay or shale by alternative raw materials, e.g. ashes

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Environmental & Geological Engineering (AREA)
  • Dispersion Chemistry (AREA)
  • Manufacture And Refinement Of Metals (AREA)

Abstract

The invention discloses a method for preparing undoped single coal gangue ceramsite based on a moving bed and ceramsite. The method comprises the steps of sequentially crushing, grinding and granulating coal gangue to obtain raw ceramsite, and sequentially drying, preheating, roasting and cooling the raw ceramsite on a moving bed to obtain the raw ceramsite with the bulk density of 550-850 kg/m3The method is low in energy consumption and environment-friendly, the obtained ceramsite product meets the national standard, the accumulation amount of the coal gangue and the environmental pollution caused by accumulation of the coal gangue are expected to be reduced, heavy metals in the coal gangue are solidified, the release of toxic metal elements is reduced, the comprehensive utilization of the coal gangue is realized, and the adverse effect of the coal gangue on the ecological environment is eliminated.

Description

Method for preparing undoped single coal gangue ceramsite based on moving bed and ceramsite
Technical Field
The invention relates to a method for treating coal gangue solid waste, in particular to a method for preparing undoped single coal gangue ceramsite by using a moving bed, and also relates to ceramsite prepared from single coal gangue, belonging to the technical field of solid waste resource utilization.
Background
The accumulation of a large amount of coal gangue not only occupies a large amount of land resources, but also causes serious environmental problems, such as soil pollution, air pollution, geological disasters and the like, so that the comprehensive utilization of the coal gangue is very important and urgent. Many scholars utilize coal gangue to prepare ceramsite, and the ceramsite is regular sphere or irregular ceramic particle with certain strength and granularity of 5-25 mm. Has good physical, chemical and hydraulic properties.
At present, in the process of preparing ceramsite by using coal gangue, in order to achieve the required performance of the ceramsite, a binder (clay, shale and the like), a foaming agent (sodium carbonate, sodium bicarbonate, silicon carbide, calcium sulfate, iron oxide and the like), a fluxing agent (manganese dioxide, sodium fluosilicate and the like) or a forming agent (water glass and the like) and the like are additionally added, and an alkaline activator (lime, sodium water glass, dihydrate gypsum and the like) is also used in a compounding manner. In the process of roasting the ceramsite, the ceramsite needs to be slowly heated, heated in multiple stages and heat-preserved in multiple stages, and even two or more devices are needed to jointly roast the ceramsite so as to ensure that the stable ceramsite is produced. The addition of a large amount of clay, shale and other non-renewable resources cannot maximize the concept of solid waste utilization and environmental protection; the use of a large amount of additives increases the production cost, reduces the treatment capacity of the coal gangue, reduces the consumption of the solid waste coal gangue, and causes the consumption and waste of a large amount of chemical products and non-renewable resources; the slow heating, the multi-stage heating and the multi-stage heat preservation, and the roasting mechanism with the cooperation of multiple devices have higher requirements on production equipment, increase the production cost, reduce the production efficiency and even cause the excessive consumption of energy.
Disclosure of Invention
The invention aims to solve the technical defects in the process of preparing ceramsite by utilizing coal gangue in the prior art, and the technical problems of difficult treatment, difficult resource utilization and the like due to the large accumulation of the coal gangue in the prior art, and provides a method for preparing undoped single coal gangue ceramsite by utilizing a moving bed.
The second purpose of the invention is to provide a ceramsite which is prepared by using single coal gangue and has low density and good mechanical property.
In order to achieve the technical purpose, the invention provides a method for preparing undoped single coal gangue ceramsite based on a moving bed.
The technical scheme of the invention utilizes single coal gangue as a raw material to prepare the ceramsite, fully utilizes the components contained in the coal gangue to obtain the ceramsite with lower density and excellent mechanical property, and utilizes SiO in the coal gangue2With Al2O3Forming a vitreous structure in a high-temperature solid-phase reaction to obtain higher mechanical strength, and utilizing Fe in the coal gangue2O3、CaO、MgO、K2O、Na2Oxides such as O play a fluxing role in the roasting process, can promote the high-temperature solid-phase reaction and reduce the liquid-phase generation temperature. Meanwhile, the technical scheme of the invention combines a moving bed to realize the sintering of the ceramsite, and the moving bed can be used for completing the processes of drying, preheating, roasting, cooling and the like of the granular materials in one step, so that the drying, puffing, solid-phase reaction and the like of the granular materials can be well controlled, and the ceramsite with low density and high mechanical strength can be obtained.
As a preferred scheme, the coal gangue comprises the following components in percentage by mass: SiO 22 52～60％；Al2O310～20％；Fe2O3、CaO、MgO、K2O and Na28 to 20 percent of O; the balance of impurities, and the total mass of all the components is 100 percent.
As a more preferable scheme, the proportion relationship of each component in the coal gangue satisfies:
Figure BDA0003008800790000021
Figure BDA0003008800790000022
wherein RO represents MgO and CaO; r2O represents Na2O and K2And O. The components of the coal gangue adopted by the invention need to meet certain proportion requirements, and the preparation of the high-performance ceramsite can be realized without additionally using additives. SiO in coal gangue2With Al2O3The synergistic matching of the Al and the Al is beneficial to obtaining the vitreous material with higher mechanical strength2O3Although the proportion is increased to improve the strength of the ceramsite, the ceramsite has high melting point and excessive Al2O3The sintering temperature of the ceramsite is increased, and the energy consumption during sintering is increased. And Fe2O3、CaO、MgO、K2O、Na2Oxides such as O and the like mainly play a fluxing role to promote solid-phase reaction and reduce the liquid-phase generation temperature, and the content of the oxides has important relation with the sintering temperature and the sintering temperature range. Therefore, the components of the coal gangue are analyzed,the proper coal gangue is screened, so that the single coal gangue can be utilized to obtain the ceramsite with excellent comprehensive performance.
As a preferable scheme, the coal gangue is ground until the granularity is less than 50 mu m, the mass percentage content of the granularity less than 20 mu m is not less than 35%, and the specific surface area is 2000-2200 cm2(ii) in terms of/g. The raw material of the coal gangue is subjected to proper grinding treatment, so that the specific surface area reaches a certain degree, the increase of the contact area among particles of the raw material is facilitated, the inter-particle contact can be more fully realized, the pelletizing performance of the raw material can be improved, in the pelletizing process, the raw ceramsite can be obtained only by controlling the water content on the premise of not using a binder, the granularity and the specific surface area of the coal gangue particles reach a certain degree, the reaction activity is improved, the roasting temperature of the finished ceramsite is reduced, the solid-phase reaction condition is better met, and the reaction is more complete and thorough.
Preferably, the particle size of the granules is 10-15 mm, and the water content is 13-16%. The proper water content is controlled to be beneficial to the subsequent puffing process of the raw ceramsite, but the raw ceramsite is easy to crack in the high-temperature sintering process due to the overhigh water content, and the raw ceramsite is difficult to bond and form due to the overlow water content.
As a preferable scheme, the moving bed is a horizontally moving chain grate, and the chain grate sequentially comprises a drying section, a preheating section, a roasting section, a cooling section I and a cooling section II from a feeding port to a discharging port; the preheating section and the roasting section adopt an air draft mode, and the cooling section I and the cooling section II adopt an air blast mode.
As a preferable scheme, the temperature of the drying section is controlled to be 100-200 ℃, the residence time of the raw material ceramsite in the drying section is 10-15 min, the temperature of the preheating section is controlled to be 350-700 ℃, the residence time of the raw material ceramsite in the drying section is 8-14 min, the temperature of the roasting section is controlled to be 1100-1200 ℃, the residence time of the raw material ceramsite in the roasting section is 10-15 min, and the cooling section I and the cooling section II are both cooled by air. The drying, puffing and sintering molding processes of the raw material ceramsite can be effectively controlled by strictly controlling the temperature and time of each stage, so that the ceramsite with low density and high mechanical strength is obtained.
As a preferable scheme, high-temperature flue gas generated in the roasting section is mixed with cold air to adjust the temperature to 350-700 ℃ and is conveyed to the preheating section, and the flue gas generated in the preheating section enters a tail gas treatment device.
As a preferred scheme, the hot flue gas generated in the cooling section I returns to the roasting section; and the hot flue gas generated in the cooling section II enters a drying section.
According to the technical scheme, the chain grate is arranged in multiple sections, and the air draft and blast designs in different stages are combined, so that the tail gas treatment process is simplified, the multi-stage utilization of heat is realized, the energy consumption is reduced, and the purposes of saving energy, reducing emission and protecting the environment are achieved.
Preferably, the bulk density is 550 to 850kg/m3The cylinder pressure strength is 2-5.5 MPa, and the compression resistance of the single ceramsite is 450-750N. The performance of the ceramsite is detected according to the GBT17431-2010 standard.
The invention adds the drying section and the preheating section in the process of preparing the ceramsite, dries and preheats the raw pellets before roasting, adjusts the chemical composition of the raw pellets, reduces the burst of the raw pellets caused by the rapid temperature change, and simultaneously gradually generates gas to achieve better expansion effect.
The invention relates to a method for preparing undoped single coal gangue ceramsite based on a moving bed, which comprises the following specific steps of:
1) crushing and grinding: crushing the coal gangue raw material to be less than 3mm by using a jaw crusher, then carrying out rod milling treatment, wherein the milling rate is 20-25 r/min, the time of each time is 10-15 min, the particle size of the milled coal gangue is less than 50 mu m, the content of the coal gangue less than 20 mu m is not less than 35%, and the specific surface area is 2000-2200 cm2(ii)/g; the coal gangue comprises the following main components in percentage by mass: SiO 22＝52～60％、Al2O3＝10～20％、Fe2O3+CaO+MgO+K2O+Na2O is 8 to 20 percent and satisfies
Figure BDA0003008800790000041
Wherein RO represents MgO and CaO; r2O represents Na2O and K2O；
2) Pelletizing and screening: putting the coal gangue powder obtained in the step 1) into a disc granulator, and adding water to prepare raw material pellets; screening the raw material pellets to obtain raw material pellets with the particle size of 10-15 mm and the water content of 13-16%;
3) moving bed roasting: continuously conveying the raw material pellets obtained in the step 2) to a moving bed which runs horizontally, wherein the moving bed is a horizontally moving chain grate which sequentially comprises a drying section, a preheating section, a roasting section, a cooling section I and a cooling section II from a feeding port to a discharging port; the preheating section and the roasting section adopt an air draft mode, and the cooling section I and the cooling section II adopt an air blast mode; distributing the raw material pellets on a grate, and sequentially drying, preheating, roasting and cooling to obtain qualified ceramsite finished products; supplementing heat to a roasting section on the chain grate through a burner, controlling the temperature of a combustion chamber to be 1100-1200 ℃, and keeping the raw material pellets in the roasting section for 10-15 min; the temperature of hot flue gas generated from a roasting section is 350-700 ℃ after the hot flue gas is added into a cold air regulation preheating section smoke hood, the heating rate is 30-50 ℃/min, the retention time of raw material pellets in the preheating section is 8-14 min, and tail gas of the preheating section is exhausted through air exhaust and enters a tail gas treatment device; and cooling the roasted ceramsite by blowing cold air into the cooling I section, returning the generated high-temperature flue gas to the roasting section, cooling the roasted ceramsite by blowing cold air into the cooling II section, feeding the generated hot flue gas into the drying section, adjusting the temperature of the drying section to be 100-200 ℃, and keeping the raw material pellets in the drying section for 10-15 min.
Compared with the prior art, the technical scheme of the invention has the advantages that:
1) the technical scheme of the invention adopts single coal gangue as a raw material to realize the preparation of the ceramsite, can not use any additives such as shale clay and the like, reduces the use of non-renewable resources and commercial chemical products, increases the use amount of solid waste coal gangue, reduces the production cost of the ceramsite, and achieves the aims of environmental protection and solid waste treatment.
2) The technical scheme of the invention can obtain the bulk density of 550-850 kg/m by using single coal gangue as a raw material3Tube pressureThe ceramsite has the advantages of strength of 2-5.5 MPa, average compression resistance of a single particle of 450-750N and good comprehensive performance.
3) The technology of the invention improves the strength of the ceramsite by optimizing the composition of the coal gangue and fully utilizing the self composition of the coal gangue without adding an additional additive and the like, reduces the sintering temperature and achieves the purposes of saving energy and reducing cost.
4) According to the technical scheme, the coal gangue is ground to a proper granularity and a proper specific surface area, so that the contact area among the raw material particles can be increased, and the solid phase particles are more fully contacted, therefore, in the pelletizing process, the raw material is easier to pelletize on the premise of not using a binder, the pelletizing performance of the raw material is improved, the granularity and the specific surface area of the coal gangue particles reach a certain degree, the reaction activity is favorably improved, the roasting temperature of the finished ceramsite is reduced, the solid phase reaction condition is better met, and the reaction is more completely and thoroughly carried out.
5) The technical scheme of the invention adopts the moving bed to produce the roasted ceramsite, and realizes that the drying, preheating, roasting and cooling processes of the raw ceramsite are completed in one device by setting the reaction stages of the drying stage, the preheating stage, the roasting stage, the cooling stage I, the cooling stage II and the like, the process is simple, and the production efficiency is improved. Especially, by adding a drying section and a preheating section, the material balls are dried and preheated before roasting, the chemical composition of the raw material ceramsite is adjusted, the explosion cracking of the raw material balls caused by rapid temperature change is reduced, gas is gradually generated, and a better puffing effect is achieved.
6) According to the technical scheme, air is blown in the cooling section, waste heat in the cooling section I is used in the roasting section, and waste heat in the cooling section II is used in the drying section; air draft is carried out in the roasting section, the waste heat of the roasting section is used in the preheating section, and the flue gas is extracted from the preheating section for tail gas treatment, so that the tail gas treatment process is simplified, the multi-stage utilization of heat is realized, the energy consumption is reduced, and the purposes of saving energy, reducing emission and protecting the environment are achieved.
7) According to the technical scheme, the temperature of the drying section and the preheating section is effectively adjusted by introducing cold air from the outside so as to achieve the proper temperature of the preheating section and the drying section.
8) The technical scheme of the invention ensures the yield of the single gangue ceramsite by adjusting the temperature in different intervals and controlling the moving speed of the moving bed, simplifies the complex ore blending process and prepares ceramsite products with different grades
Drawings
Fig. 1 is a diagram of a ceramsite preparation process device (a schematic diagram of a production line structure): 1 is a drying section; 2 is a preheating section; 3 is a roasting section; 4, cooling section I; 5 is a cooling section II; 6 is a fan; 7 is a tail gas treatment device; 8 is a burner; and 9 is an air valve.
Detailed Description
In order to facilitate an understanding of the invention, the invention will be described in more complete detail with reference to the preferred embodiments, but the scope of the invention is not limited to the specific embodiments described below.
Unless otherwise defined, all terms of art used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention.
Unless otherwise specified, the reagents and materials used in the present invention are commercially available products or products obtained by a known method.
The following examples 1 and 2 and comparative example 1 are given by taking coal gangue from a certain region as an example, and the chemical composition is as follows2 54.43％、Al2O313.82％、Fe2O3 1.29％、CaO 1.97％、K2O 2.60％、Na2O2.65%, MgO 2.65%, and the balance of impurities including heavy metals, wherein Fe2O3+CaO+MgO+K2O+Na2O＝11.16％，
Figure BDA0003008800790000061
Example 1
(1) Crushing coal gangue raw material to below 3mm by a jaw crusher, grinding twice at 20r/min by a rod mill for 15min respectively until the particle size is less than50 μm, 35% of less than 20 μm, and a specific surface area of 2000cm2And (g), then, passing the powder through a disc granulator to prepare raw balls with the diameter of 10-15 mm, wherein the water content of the raw balls is 16%.
(2) Placing the ceramsite raw material balls into a moving bed, drying, preheating, roasting and cooling to obtain roasted ceramsite, wherein the temperature of a drying section is as follows: the retention time of the ceramsite is as follows at 100 ℃: 15 min; temperature of the preheating section: 700 ℃, the heating rate is 30 ℃/min, and the retention time of the ceramsite is as follows: 14 min; temperature of roasting section: 1100 ℃, retention time of ceramsite: 15 min; the cooling section is cooled by air.
(3) The product performance is tested according to GBT17431-2010, and the bulk density of the ceramsite is 850kg/m3The cylinder pressure strength is 5.6MPa, and the pressure resistance of single ceramsite is 753N. According to the standard, the cylinder pressure strength of the ceramsite with the density grade of 900 is more than 5.0MPa, so that the ceramsite meets the standard.
Example 2
(1) Crushing coal gangue raw material to below 3mm by a jaw crusher, grinding twice at 25r/min by a rod mill for 10min respectively until the particle size is less than 50 μm, wherein the content of less than 20 μm is 50%, and the specific surface area is 2200cm2And (g), then, passing the powder through a disc granulator to prepare raw balls with the diameter of 10-15 mm, wherein the water content of the raw balls is 13%.
(2) Placing the ceramsite raw material balls into a moving bed, drying, preheating, roasting and cooling to obtain roasted ceramsite, wherein the temperature of a drying section is as follows: 200 ℃, ceramsite retention time: 10 min; temperature of the preheating section: 350 ℃, the heating rate is 50 ℃/min, and the retention time of the ceramsite is as follows: 8 min; temperature of roasting section: 1200 ℃, retention time of ceramsite: 10 min; the cooling section is cooled by air.
(3) The product performance is tested according to GBT17431-2010, and the ceramsite bulk density is 549kg/m3The cylinder compressive strength is 3.5MPa, and the compressive strength of single ceramsite is 476N. According to the ceramsite with the standard density grade of 600, the cylinder pressure strength of the ceramsite is more than 2.0MPa, so that the ceramsite meets the standard.
Comparative example 1
(1) Crushing the coal gangue raw material to below 3mm by a jaw crusher, grinding the coal gangue raw material once at 20r/min by a rod mill for 10min until the granularity is less than 200 mu m, and then passing the powder through a disk granulator to prepare 10-15 mm ceramsite raw material balls with the water content of 13%.
(2) Placing the ceramsite raw material balls into a moving bed, drying, preheating, roasting and cooling to obtain roasted ceramsite, wherein the temperature of a drying section is as follows: 200 ℃, ceramsite retention time: 10 min; temperature of the preheating section: 350 ℃, the heating rate is 50 ℃/min, and the retention time of the ceramsite is as follows: 8 min; temperature of roasting section: 1200 ℃, retention time of ceramsite: 10 min; the cooling section is cooled by air.
(3) Inspecting the product performance according to GBT17431-2010, wherein the ceramsite bulk density is 651kg/m3The cylinder pressure strength is 1.5MPa, and the single ceramsite compression strength is 338N. According to the standard, the cylinder pressure strength of the ceramsite with the density grade of 700 is required to be more than 3.0MPa, so that the ceramsite does not meet the standard.
Comparative example 2
Taking coal gangue from a certain area as an example, the chemical composition is as follows2 55.95％、Al2O324.33％、Fe2O31.43％、CaO 1.19％、K2O 2.28％、Na2O1.57% and MgO 0.76%, wherein Fe2O3+CaO+MgO+K2O+Na2O＝7.23％，
Figure BDA0003008800790000081
(1) Crushing coal gangue raw material to below 3mm by a jaw crusher, grinding twice at 20r/min by a rod mill for 15min until the granularity is less than 50 μm, wherein the content of less than 20 μm is 35%, and the specific surface area is 2000cm2And (g), then, passing the powder through a disc granulator to prepare raw balls with the diameter of 10-15 mm, wherein the water content of the raw balls is 16%.
(2) Placing the ceramsite raw material balls into a moving bed, drying, preheating, roasting and cooling to obtain roasted ceramsite, wherein the temperature of a drying section is as follows: the retention time of the ceramsite is as follows at 100 ℃: 15 min; temperature of the preheating section: 700 ℃, the heating rate is 30 ℃/min, and the retention time of the ceramsite is as follows: 14 min; temperature of roasting section: 1100 ℃, retention time of ceramsite: 15 min; the cooling section is cooled by air.
(3) The product performance is tested according to GBT17431-2010, and the bulk density of the ceramsite is 863kg/m3The cylinder compressive strength is 3.6MPa, and the compressive strength of single ceramsite is 482N. According to the standard, the ceramic particles with the density grade of 900 have the cylinder pressure strength of more than 5.0MPa, so the ceramic particles do not meet the standard.
As can be seen from comparative examples 1 and 2 and examples 1 and 2, the appropriate raw material composition and the appropriate production process can reduce the bulk density and improve the hardness of the ceramsite so that the cylinder pressure strength reaches the standard, thereby obtaining the qualified ceramsite product.

Claims (10)

1. A method for preparing undoped single coal gangue ceramsite based on a moving bed is characterized by comprising the following steps: the method comprises the following steps of sequentially crushing, grinding and granulating the coal gangue to obtain raw ceramsite, and sequentially drying, preheating, roasting and cooling the raw ceramsite on a moving bed to obtain the coal gangue ceramsite.
2. The method for preparing undoped single coal gangue ceramsite based on moving bed according to claim 1, wherein the method comprises the following steps: the coal gangue comprises the following components in percentage by mass: SiO 22 52～60％；Al2O310～20％；Fe2O3、CaO、MgO、K2O and Na28 to 20 percent of O; the balance of impurities, and the total mass of all the components is 100 percent.
3. The method for preparing undoped single coal gangue ceramsite based on moving bed according to claim 2, wherein the method comprises the following steps: the proportion relation of each component in the coal gangue meets the following requirements:
Figure FDA0003008800780000011
wherein RO represents MgO and CaO; r2O represents Na2O and K2O。
4. The method for preparing undoped single coal gangue ceramsite based on moving bed according to any one of claims 1 to 3, wherein the method comprises the following steps: said coalGrinding the gangue until the granularity is less than 50 mu m, the mass percentage content of the granularity less than 20 mu m is not less than 35 percent, and the specific surface area is 2000-2200 cm2/g。
5. The method for preparing undoped single coal gangue ceramsite based on moving bed according to claim 1, wherein the method comprises the following steps: the particle size of the raw ceramsite is 10-15 mm, and the water content is 13-16%.
6. The method for preparing undoped single coal gangue ceramsite based on moving bed according to claim 1, wherein the method comprises the following steps: the moving bed is a horizontally moving chain grate machine, and the chain grate machine is sequentially divided into a drying section, a preheating section, a roasting section, a cooling I section and a cooling II section from a feeding port to a discharging port; the preheating section and the roasting section adopt an air draft mode, and the cooling section I and the cooling section II adopt an air blast mode.
7. The method for preparing undoped single coal gangue ceramsite based on moving bed according to claim 1 or 6, wherein the moving bed comprises the following steps: the temperature of the drying section is controlled to be 100-200 ℃, the retention time of the raw material ceramsite in the drying section is 10-15 min, the temperature of the preheating section is controlled to be 350-700 ℃, the retention time of the raw material ceramsite in the drying section is 8-14 min, the temperature of the roasting section is controlled to be 1100-1200 ℃, the retention time of the raw material ceramsite in the roasting section is 10-15 min, and the cooling section I and the cooling section II are both cooled by air.
8. The method for preparing undoped single coal gangue ceramsite based on moving bed according to claim 7, wherein the method comprises the following steps: high-temperature flue gas generated in the roasting section is mixed with cold air to adjust the temperature to 350-700 ℃ and is conveyed to the preheating section, and the flue gas generated in the preheating section enters a tail gas treatment device.
9. The method for preparing undoped single coal gangue ceramsite based on moving bed according to claim 7, wherein the method comprises the following steps: cooling the hot flue gas generated in the first section and returning the hot flue gas to the roasting section; and the hot flue gas generated in the cooling section II enters a drying section.
10. The undoped single coal gangue ceramsite prepared by the method of any one of claims 1 to 9 is characterized in that: a bulk density of 550 to 850kg/m3The cylinder pressure strength is 2-5.5 MPa, and the compression resistance of the single ceramsite is 450-750N.
CN202110369692.7A 2021-04-07 2021-04-07 Method for preparing undoped single coal gangue ceramsite based on moving bed and ceramsite Active CN113105258B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110369692.7A CN113105258B (en) 2021-04-07 2021-04-07 Method for preparing undoped single coal gangue ceramsite based on moving bed and ceramsite

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110369692.7A CN113105258B (en) 2021-04-07 2021-04-07 Method for preparing undoped single coal gangue ceramsite based on moving bed and ceramsite

Publications (2)

Publication Number Publication Date
CN113105258A true CN113105258A (en) 2021-07-13
CN113105258B CN113105258B (en) 2022-04-05

Family

ID=76714369

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110369692.7A Active CN113105258B (en) 2021-04-07 2021-04-07 Method for preparing undoped single coal gangue ceramsite based on moving bed and ceramsite

Country Status (1)

Country Link
CN (1) CN113105258B (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113526976A (en) * 2021-07-20 2021-10-22 成都建筑材料工业设计研究院有限公司 Method for preparing ceramsite by utilizing coal gangue and steel slag and ceramsite
CN113698175A (en) * 2021-07-28 2021-11-26 上格环境科技（上海）有限公司 Coal gangue ceramsite and preparation method thereof
CN114907140A (en) * 2022-04-21 2022-08-16 陕西科技大学 Preparation method of coal-based solid waste water-retaining ceramsite with drought resistance for agriculture and forestry
CN114990329A (en) * 2022-05-26 2022-09-02 中南大学 Method for preparing high-strength lightweight aggregate by pellet roasting method

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009003340A1 (en) * 2007-06-29 2009-01-08 Xiaoyong Zhang Bio-fertilizer adsorbent material synthesized from fly ash and coal gangue and preparation method thereof
CN101624647A (en) * 2009-08-04 2010-01-13 武汉钢铁(集团)公司 Pellet roasting production technology recycling residual heat and system thereof
CN104261866A (en) * 2014-08-04 2015-01-07 金立虎 Production method for coal gangue ceramsite
CN109809724A (en) * 2018-12-04 2019-05-28 中国地质调查局沈阳地质调查中心 A kind of bastard coal ground mass haydite and preparation method thereof
CN110104979A (en) * 2019-05-15 2019-08-09 中南大学 A method of gangue lightweight aggregate is prepared using belt sintering
CN110104975A (en) * 2019-05-15 2019-08-09 中南大学 A kind of technique that belt type roasting machine pelletizing method prepares gangue lightweight aggregate
CN110683850A (en) * 2019-11-18 2020-01-14 淮南亿万达集团有限责任公司 Production process of gangue ceramsite
CN211367682U (en) * 2019-07-22 2020-08-28 中冶长天国际工程有限责任公司 Grate-rotary kiln system

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009003340A1 (en) * 2007-06-29 2009-01-08 Xiaoyong Zhang Bio-fertilizer adsorbent material synthesized from fly ash and coal gangue and preparation method thereof
CN101624647A (en) * 2009-08-04 2010-01-13 武汉钢铁(集团)公司 Pellet roasting production technology recycling residual heat and system thereof
CN104261866A (en) * 2014-08-04 2015-01-07 金立虎 Production method for coal gangue ceramsite
CN109809724A (en) * 2018-12-04 2019-05-28 中国地质调查局沈阳地质调查中心 A kind of bastard coal ground mass haydite and preparation method thereof
CN110104979A (en) * 2019-05-15 2019-08-09 中南大学 A method of gangue lightweight aggregate is prepared using belt sintering
CN110104975A (en) * 2019-05-15 2019-08-09 中南大学 A kind of technique that belt type roasting machine pelletizing method prepares gangue lightweight aggregate
CN211367682U (en) * 2019-07-22 2020-08-28 中冶长天国际工程有限责任公司 Grate-rotary kiln system
CN110683850A (en) * 2019-11-18 2020-01-14 淮南亿万达集团有限责任公司 Production process of gangue ceramsite

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113526976A (en) * 2021-07-20 2021-10-22 成都建筑材料工业设计研究院有限公司 Method for preparing ceramsite by utilizing coal gangue and steel slag and ceramsite
CN113698175A (en) * 2021-07-28 2021-11-26 上格环境科技（上海）有限公司 Coal gangue ceramsite and preparation method thereof
CN114907140A (en) * 2022-04-21 2022-08-16 陕西科技大学 Preparation method of coal-based solid waste water-retaining ceramsite with drought resistance for agriculture and forestry
CN114990329A (en) * 2022-05-26 2022-09-02 中南大学 Method for preparing high-strength lightweight aggregate by pellet roasting method
CN114990329B (en) * 2022-05-26 2023-10-24 中南大学 Method for preparing high-strength lightweight aggregate by pellet roasting method

Also Published As

Publication number Publication date
CN113105258B (en) 2022-04-05

Similar Documents

Publication Publication Date Title
CN113105258B (en) Method for preparing undoped single coal gangue ceramsite based on moving bed and ceramsite
CN103667675A (en) Treatment method of laterite-nickel ore
CN104263911B (en) The preparation method of sintering ore of vanadium-titanium magnetite ore
CN112142445A (en) Method for preparing ceramsite by mixing municipal domestic sludge and shale
CN112553462A (en) Sintered ore containing sintered dedusting ash pellets and preparation method thereof
CN112430062A (en) Preparation method of light high-strength ceramsite, prepared light high-strength ceramsite and application
JPS6048457B2 (en) Manufacturing method of cellular glass beads
CN113333770B (en) Preparation method of powder metallurgy iron powder
CN113351872B (en) Preparation method of powder metallurgy iron powder based on electromagnetic field effect
CN101177731B (en) Method for preparing sintered ore
US20240067564A1 (en) Method for preparing cementing material by sintering activation of coal gangue
CN114574693A (en) Sintering process of all-vanadium titano-magnetite pellets
CN111825474A (en) Coal gangue ceramsite and preparation method thereof
CN109097561B (en) Method for producing low-silicon-melting-agent pellets by large-scale belt type roasting machine
CN115010508B (en) Method for preparing ceramsite green body from iron tailings and coal gangue
CN102296175B (en) Method for producing oxidized pellets by using gold ore tailing and limonite
CN105463146A (en) Method for carrying out direct reduction processing on hematite through rotary hearth furnace to produce granular iron
CN102618685A (en) Energy-saving environmental-protection two-grinding one-burning method iron ore cokeless iron making and cement clinker producing technology
CN106479543B (en) The cold burnt broken coking coal pretreating process to dry is put out based on dry
CN105603179A (en) Process for granulating, shaping and sintering phosphate powder
CN114574695B (en) Sintering method of iron-manganese ore pellets
CN115321864B (en) Method for cooling coal gangue on belt sintering decarburization machine
CN117209253B (en) Method for preparing ultra-light ceramsite by utilizing gangue to cooperate with solid waste
CN115700284B (en) Method for preparing high-quality DRI by taking whole hematite powder as raw material
CN111304435B (en) Pellet energy-saving and emission-reducing method for activating hard-to-burn iron ore through mechanical and chemical coupling

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant