CN108585712B

CN108585712B - Preparation method of large-mixing-amount solid waste wet grinding slurry composite waste EPS particle heat insulation material

Info

Publication number: CN108585712B
Application number: CN201810460334.5A
Authority: CN
Inventors: 苏英; 蒋健; 贺行洋; 杨进; 陈顺; 陈威; 卢敏; 黄健翔; 徐焰; 彭凯; 张海峰
Original assignee: Hubei University of Technology
Current assignee: Hubei University of Technology
Priority date: 2018-05-15
Filing date: 2018-05-15
Publication date: 2021-09-03
Anticipated expiration: 2038-05-15
Also published as: CN108585712A

Abstract

The invention discloses a preparation method of a large-mixing-amount solid waste wet grinding slurry composite waste EPS particle heat insulation material, which adopts the technical scheme that 40-50 parts of slag and 30-35 parts of steel slag are subjected to wet grinding and then are mixed with 5-8 parts of water, 4-6 parts of desulfurized gypsum, 0.3-0.5 part of fiber, 0.08-0.12 part of rubber powder and 0.13-0.21 part of suspending agent to be uniformly stirred, 10-15 parts of cement, 3-5 parts of early strength cement, 3-6 parts of carbide slag and 0.05-0.12 part of water reducing agent are added to be uniformly stirred, and slurry is obtained; and chopping the waste EPS boards, modifying the chopped waste EPS boards by using a coupling agent, and mixing and stirring the modified waste EPS boards and the slurry uniformly to obtain the heat-insulating material. The invention has simple process, low production cost, large mixing amount of waste materials and excellent performance.

Description

Preparation method of large-mixing-amount solid waste wet grinding slurry composite waste EPS particle heat insulation material

Technical Field

The invention relates to the technical field of building heat preservation, in particular to a preparation method of a large-mixing-amount solid waste wet grinding slurry composite waste EPS particle heat preservation material.

Background

The traditional heat-insulating material is mainly used for improving gas phase void ratio and reducing heat conductivity coefficient and conduction coefficient. The fiber heat-insulating material needs a thicker coating layer to increase the convective heat transfer and the radiant heat transfer in the use environment; the section inorganic heat-insulating material needs to be assembled and constructed, and has the defects of more seams, attractive appearance, poor waterproofness, short service life and the like. Therefore, a new material capable of greatly improving the heat insulation reflection performance of the heat insulation material is continuously sought and researched.

On the other hand, the problem of waste slag treatment and resource utilization in iron and steel enterprises is more and more emphasized, and particularly, the utilization rate of converter steel slag called poor-quality cement clinker is only 10-20%. Slag also plays an important role in industrial production, and particularly in heavy and large-scale plants, it is necessary and urgent to select a proper treatment process and a utilization path to develop the recycling value of steel slag and slag in order to create economic and environmental benefits for industrial waste.

In the prior art, the use of foamed plastic for the preparation of thermal insulation materials has been reported everywhere, for example, in the related patent of the disclosed thermal insulation wall, patent CN103044860B discloses a composite type foamed thermal insulation material and a preparation method thereof, and the composite type foamed thermal insulation material comprises the following components in percentage by weight: epoxy resin: 10-20%, curing agent: 10-15%, fly ash: 40-60%, diluent: 10-20%, flame retardant: 2-4%, hydrogen peroxide: 2-4%, foaming agent: 0.2 to 0.4 percent. In the scheme, because the foaming agent causes the object substance to form pores, the strength is greatly reduced due to nonuniform pore forming, and therefore, a special process is required for control, and the simplification of the process cannot be realized.

Patent CN101012332B discloses a lignin, waste hard foam powder fluorine-free polyurethane thermal insulation material and a preparation method thereof. The polyurethane foaming agent comprises 10-16 parts of isocyanate, 6-10 parts of polyether polyol, 0.05-0.25 part of water, 2-3.5 parts of a physical foaming agent, 0.05-0.2 part of a foam homogenizing agent, 0.04-0.08 part of a catalyst, 0.1-3 parts of lignin and 0.1-2 parts of waste hard acid foam powder. The main raw materials in the scheme are lignin and hard foam powder which are all organic light materials, and the formed materials have the problems of low ignition point, low compressive strength and low bonding strength with a foundation wall, so the material is flammable, has a large deformation coefficient and poor safety, and cannot realize the sustainable development benefit with high durability.

Patent CN103408321B discloses a polystyrene foam particle-magnesium oxychloride cement composite thermal insulation material. The weight percentages are as follows: 49.81-52.13% of magnesium oxychloride cement, 16.76-17.52% of industrial waste residue, 1.83-5.61% of EPS granules, 0.37-0.81% of PPF fiber, 0-0.21% of foaming agent and 26.89-28.10% of water. In the technical scheme, because the industrial waste residue and the EPS particles have large difference, and the problems of untight interface connection and uneven particle dispersion exist when the industrial waste residue and the EPS particles are mixed, the mixing amount of the industrial waste residue is low, and the green and environment-friendly benefits of high waste utilization and high energy conservation can not be realized.

Therefore, a method which can utilize more industrial waste, has low production cost and simple process and can obtain a thermal insulation material with more excellent performance is required to be developed.

Disclosure of Invention

The invention aims to solve the technical problems and provides a preparation method of the large-mixing-amount solid waste wet grinding slurry composite waste EPS particle heat insulation material, which has the advantages of simple process, low production cost, large waste mixing amount and excellent various performances.

The technical scheme comprises the following steps:

1) 40-50 parts of slag is taken according to the weight part and put into a wet grinder to be wet-grinded by adding water according to the water-cement ratio of 0.5 to obtain wet-grinded slag for standby; 30-35 parts of steel slag are put into a wet grinder and wet ground according to the water-cement ratio of 0.5, and wet ground steel slag is obtained for standby; cutting the waste EPS boards into particles to obtain waste EPS particles for later use;

2) putting the wet-milled slag and the wet-milled steel slag obtained in the step 1) into a stirrer, adding 5-8 parts by weight of water, 4-6 parts by weight of desulfurized gypsum, 0.3-0.5 part by weight of fiber, 0.08-0.12 part by weight of rubber powder and 0.13-0.21 part by weight of suspending agent, uniformly stirring, adding 10-15 parts by weight of cement, 3-5 parts by weight of early strength cement, 3-6 parts by weight of carbide slag and 0.05-0.12 part by weight of water reducer, and uniformly stirring to obtain slurry;

3) taking 4-8 parts by weight of the waste EPS particles prepared in the step 1), adding 0.12-0.53 part by weight of coupling agent and 10-20 parts by weight of water, mixing and stirring uniformly, soaking, and drying to obtain modified EPS particles;

4) and (3) placing the slurry prepared in the step 2) and the modified EPS particles prepared in the step 3) into a stirrer to be uniformly stirred to obtain the heat-insulating material.

Further, the particle size of the particles of the slag after wet grinding in the step (1) is less than or equal to 6 μm; the particle size of the steel slag after wet grinding is less than or equal to 8 mu m; the particle size of the cut waste EPS particles is 1-3 mm; the diameter of the fiber in the step (2) is less than or equal to 2mm, and the particle size range of the carbide slag is 2-10 mm.

Further, in the step (3), the waste EPS particles, the coupling agent and water are uniformly mixed and stirred, and then soaked for 1-3 days at the drying temperature of 40-60 ℃ for 6-12 h.

Further, the water reducing agent consists of a polycarboxylic acid water reducing agent and a naphthalene water reducing agent, and the mixing ratio of the polycarboxylic acid water reducing agent to the naphthalene water reducing agent is 2-3: 1.

further, the coupling agent is an oligosiloxane.

Further, the cement is ordinary portland cement; the early strength cement is sulphoaluminate cement.

Further, the rubber powder is HJS-09 plastic powder; the suspending agent is difenoconazole or pendimethalin; the fibers are aluminum silicate fibers or basalt fibers.

In view of the problems in the background art, the inventors made the following improvements: (1) modifying the waste EPS: cutting the waste EPS boards into particles, mixing with a coupling agent, stirring, soaking and drying, wherein the modification process comprises four steps: firstly, hydrolyzing SiX group connected with silicon atom to generate SiOH; dehydrating and condensing Si-OH to produce oligomeric siloxane containing Si-OH; ③ SiOH in the oligosiloxane forms hydrogen bonds with OH on the surface of EPS particles; and fourthly, in the heating and curing process, covalent bonds are formed with the rough EPS particles along with dehydration reaction. The silicon hydroxyl part generated by hydrolysis of the silane coupling agent on the EPS particle interface forms a hydrogen bond with the EPS surface, the rest silicon hydroxyl can be condensed with Si-OH in secondary hydrolysate of slag and steel slag or is in a free state, and the coupling agent is preferably oligosiloxane. (2) The glass body of the slag and the steel slag after wet grinding contains more Ca extranet bodies²⁺Etc. the vitreous network is relatively loose and the Ca contained therein is present during the wet-milling treatment and the placement²⁺The metal ions are easy to dissolve out, the action of an aqueous medium and the metal ions on a slag and steel slag vitreous body network is promoted, and the secondary hydration reaction capability of the slag and the steel slag can be enhanced; on the other hand, the body of secondary hydration products in the slag and the steel slag can be increasedThe volume fraction is beneficial to the bonding of slag and steel slag particles in the set cement, thereby improving the strength of the powder. (3) And (3) finally, carrying out mixing reaction on the modified EPS particles and the slurry obtained in the step (2), wherein the slag and the steel slag after wet grinding have great activity, the bonding capability with the modified EPS particles is further enhanced, and two material interfaces with great difference in performance, namely industrial waste (steel slag and slag) and the modified EPS particles, can be coupled. The wet grinding process is combined with the EPS modification process, so that the performance of the composite material is improved, the bonding strength is increased, the various properties of the material are comprehensively improved, and the novel composite material with excellent and reliable performance is obtained.

Furthermore, slag and steel slag replace most of cement, so that the cement consumption is saved, the waste utilization rate is up to more than 85%, the slag and steel slag are really large in doping amount, and the production cost is effectively reduced; the slag and the steel slag which are generally difficult to utilize are wet-milled to micron-level or even submicron-level, and the cohesiveness of the cement slurry is greatly improved due to the micro-concentration effect, so that the early strength of the set cement is obviously enhanced; meanwhile, according to the compact packing theory, the cement, the slag, the steel slag and the modified EPS particles are blended according to the proportion and combined in an excellent gradation manner, so that the strength of the powder is greatly improved. The doping of the fibers increases the toughness of the material, and enhances the tensile resistance and bending resistance, and the fibers are preferably aluminum silicate fibers or basalt fibers; the rubber powder and the suspending agent are blended to stably and uniformly disperse the foam fiber in the slurry, the rubber powder is preferably HJS-09 plastic powder, and the suspending agent is preferably difenoconazole or pendimethalin; the carbide slag contains a large amount of calcium hydroxide and can hydrolyze a large amount of OH in water^-Thereby better exciting the activity of the slag and the steel slag; the incorporation of the desulfurized gypsum, the micro-expansion of itself, interacts with the shrinkage of the cementitious material itself, thereby reducing drying shrinkage. The mixed various waste materials and the auxiliary agent are matched together to prepare the green heat-insulating material with high waste utilization rate, light weight, high strength, low heat conductivity coefficient and high softening coefficient.

Furthermore, the soaking time in the modification process of the waste EPS particles is preferably 1 to 3 days, and too long soaking time can cause modified foam particles to react with CO in the air₂And will fail, too short will result in insufficient adsorption of the coupling agent onto the foam particles, the drying temperature is preferably 40-60 c, too high will result in melting of the foam particles, too low will result in residual moisture still adhering to the particle surface.

Further, the water reducing agent is composed of a polycarboxylic acid water reducing agent and a naphthalene water reducing agent, the two types of water reducing agents are mixed to have the effects of reducing thermal sensitivity, reducing cost and enhancing adaptability, and the mixing ratio of the two types of water reducing agents is preferably 2-3: 1, too high would be too sensitive to temperature, resulting in insufficient slump retention at high temperatures; too low can cause poor adaptability with cement, so that the water reducing agent cannot be fully utilized.

The method has simple process, low production cost and large mixing amount of waste materials, can couple the interfaces of two materials with greatly different properties by modifying the EPS particles and compounding the modified EPS particles with slag and steel slag, thereby improving the property of the composite material and increasing the bonding strength, further comprehensively improving the various properties of the material by limiting the particle size of the main component and combining a wet grinding process, and obtaining a novel composite material with excellent and reliable property, wherein the produced heat-insulating material has light volume weight, high strength, small shrinkage, large softening coefficient, high heat insulation and waste utilization rate, and the dry density is less than or equal to 700kg/m³The 7d compressive strength is more than or equal to 5Mpa, the heat conductivity coefficient is less than or equal to 0.12w/(m.k), the softening coefficient is more than or equal to 0.82, the linear shrinkage is less than or equal to 0.15 percent, and the waste utilization rate is more than or equal to 85 percent.

Detailed Description

Example of the Process

1) Putting the slag into a wet grinder, adding water into the slag according to the water-cement ratio of 0.5, and wet-grinding the slag until the particle size is less than or equal to 6 mu m to obtain wet-ground slag for later use; putting the steel slag into a wet grinder, adding water according to the water-cement ratio of 0.5, and wet grinding the steel slag until the particle size is less than or equal to 8 mu m to obtain wet-ground steel slag for later use; the waste EPS boards are cut into particles of 1-3 mm, and waste EPS particles are obtained for later use;

2) putting the wet-milled slag and the wet-milled steel slag obtained in the step 1) into a stirrer, adding water, desulfurized gypsum, fibers with the diameter less than or equal to 2mm, rubber powder and a suspending agent in parts by weight, uniformly stirring, adding cement, early strength cement, carbide slag with the particle size range of 2-10mm and a water reducing agent, and uniformly stirring to obtain slurry;

3) taking the waste EPS particles prepared in the step 1) according to the weight parts, adding a coupling agent and water, mixing and stirring uniformly, soaking for 1-3 days, and drying for 6-12 hours at the temperature of 40-60 ℃. Obtaining modified EPS particles;

The process comprises the following steps: the water reducing agent consists of a polycarboxylic acid water reducing agent and a naphthalene water reducing agent, and the mixing ratio of the polycarboxylic acid water reducing agent to the naphthalene water reducing agent is 2-3: 1; the coupling agent is oligosiloxane; the cement is ordinary portland cement; the early strength cement is sulphoaluminate cement; the rubber powder is HJS-09 plastic powder; the suspending agent is difenoconazole or pendimethalin; the fibers are aluminum silicate fibers or basalt fibers.

Comparative example 1:

the procedure is as in example 1 except that no coupling agent is added, step (3) is omitted and no modification of the waste EPS particles is carried out.

Comparative example 2:

the procedure of example 1 was followed, except that the wet milling of the steel slag and the slag was not conducted in step (1) was omitted.

Table 1: examples 1-6 the composition ratio table (parts by weight) of each component:

	example 1	Example 2	Example 3	Example 4	Example 5	Example 6
							Slag of mine	40	42	44	46	48	50
Steel slag	30	32	34	34	35	35
							Water (W)	5	6	7	7	8	8
Waste EPS particles	4	5	6	7	8	8
							Cement	10	11	12	13	14	15
Early strength cement	3	3	4	4	5	5
							Carbide slag	3	3	4	4	5	6
Desulfurized gypsum	4	4	5	5	6	6
							Fiber	0.3	0.3	0.4	0.4	0.4	0.5
Coupling agent	0.12	0.16	0.25	0.33	0.4	0.53
							Rubber powder	0.05	0.08	0.10	0.11	0.11	0.12
Suspending agent	0.13	0.13	0.15	0.18	0.20	0.21
							Water reducing agent	0.05	0.06	0.08	0.09	0.10	0.12

Table 2: performance data for examples 1-6 and comparative examples 1, 2

As can be seen from the above table: the 7d compressive strength is reduced to some extent but can reach the standard as seen in the comparative example 1, but the heat conductivity coefficient is obviously increased and cannot reach the standard, and other indexes are not obviously changed; in comparative example 2, the softening coefficient is obviously reduced, the 7d compressive strength is also greatly reduced, the softening coefficient and the strength of the steel sheet do not meet the standard, and other indexes have no obvious change. To sum up: the coupling agent is added to modify the waste EPS particles, so that the strength and the heat conductivity coefficient are obviously influenced, and particularly, the heat conductivity coefficient is greatly reduced; the wet grinding of the steel slag and the slag has obvious influence on the strength and the softening coefficient, and particularly greatly improves the strength.

Claims

1. The preparation method of the large-mixing-amount solid waste wet grinding slurry composite waste EPS particle heat insulation material is characterized by comprising the following steps of:

1) 40-50 parts of slag is taken according to the weight part and put into a wet grinder to be wet-grinded by adding water according to the water-cement ratio of 0.5 to obtain wet-grinded slag for standby; 30-35 parts of steel slag are put into a wet grinder and wet ground according to the water-cement ratio of 0.5, and wet ground steel slag is obtained for standby; cutting the waste EPS boards into particles to obtain waste EPS particles for later use; wherein, the particle size of the slag after wet grinding is less than or equal to 6 μm; the particle size of the steel slag after wet grinding is less than or equal to 8 mu m; the particle size of the cut waste EPS particles is 1-3 mm;

2) putting the wet-milled slag and the wet-milled steel slag obtained in the step 1) into a stirrer, adding 5-8 parts by weight of water, 4-6 parts by weight of desulfurized gypsum, 0.3-0.5 part by weight of fiber, 0.08-0.12 part by weight of rubber powder and 0.13-0.21 part by weight of suspending agent, uniformly stirring, adding 10-15 parts by weight of cement, 3-5 parts by weight of early strength cement, 3-6 parts by weight of carbide slag and 0.05-0.12 part by weight of water reducer, and uniformly stirring to obtain slurry; wherein the diameter of the fiber is less than or equal to 2mm, and the particle size range of the carbide slag is 2-10 mm;

2. The method for preparing the thermal insulation material of the waste EPS particles in the form of the large-dosage wet grinding slurry for solid wastes according to claim 1, wherein in the step (3), the waste EPS particles, the coupling agent and water are uniformly mixed and stirred, and then are soaked for 1-3 days, the drying temperature is 40-60 ℃, and the drying time is 6-12 h.

3. The preparation method of the high-volume solid waste wet grinding slurry composite waste EPS particle thermal insulation material as claimed in claim 1 or 2, wherein the water reducing agent is composed of a polycarboxylic acid water reducing agent and a naphthalene water reducing agent, and the mixing ratio of the polycarboxylic acid water reducing agent to the naphthalene water reducing agent is 2-3: 1.

4. the method for preparing the high-volume solid waste wet grinding slurry composite waste EPS particle thermal insulation material as claimed in claim 1 or 2, wherein the coupling agent is oligosiloxane.

5. The method for preparing the high-volume solid waste wet grinding slurry composite waste EPS particle thermal insulation material as claimed in claim 1 or 2, wherein the cement is ordinary portland cement; the early strength cement is sulphoaluminate cement.

6. The preparation method of the high-volume solid waste wet grinding slurry composite waste EPS particle thermal insulation material as claimed in claim 1 or 2, wherein the rubber powder is HJS-09 plastic powder; the suspending agent is difenoconazole or pendimethalin; the fibers are aluminum silicate fibers or basalt fibers.