阅读说明：本技术 一种由煤矸石制备的支座砂浆促凝剂的应用方法 (Application method of support mortar coagulant prepared from coal gangue ) 是由 苏英 吴磊 贺行洋 赵浩祥 张权钢 马庆红 王传辉 杨进 王迎斌 郑正旗 于 2020-12-19 设计创作，主要内容包括：本发明公布一种由煤矸石制备的支座砂浆促凝剂的应用方法,该煤矸石促凝剂的制备方法如下：先将煤矸石破碎后干磨得到粒径100～500μm的煤矸石粉,再按重量份数,将煤矸石粉20～30份、水150～160份、研磨体240～300份、表面钝化剂0.01～0.05份加入湿磨设备中研磨40min～60min,得到0.3μm以下的煤矸石浆体。该促凝剂在支座砂浆的应用：普通硅酸盐水泥25～45份、水7～20份、煤矸石促凝剂2～10份、石英砂40～60份、高效减水剂0.1～0.25份、膨胀剂3～5.5份、消泡剂0.03～0.2份、复合纤维0.05～0.3份。其制得的支座砂浆早期强度2h可达22.9～24.8MPa,后期强度可达70MPa以上且不倒缩,流动度提高了40～60％。(The invention discloses an application method of a support mortar coagulant prepared from coal gangue, and the preparation method of the coal gangue coagulant comprises the following steps: firstly crushing coal gangue, then carrying out dry grinding to obtain coal gangue powder with the particle size of 100-500 mu m, and adding 20-30 parts of coal gangue powder, 150-160 parts of water, 240-300 parts of grinding body and 0.01-0.05 part of surface passivator into wet grinding equipment according to parts by weight for grinding for 40-60 min to obtain coal gangue slurry with the particle size of less than 0.3 mu m. The application of the coagulant in the support mortar is as follows: 25-45 parts of ordinary portland cement, 7-20 parts of water, 2-10 parts of a coal gangue coagulant, 40-60 parts of quartz sand, 0.1-0.25 part of a high-efficiency water reducing agent, 3-5.5 parts of an expanding agent, 0.03-0.2 part of a defoaming agent and 0.05-0.3 part of a composite fiber. The early strength of the prepared support mortar can reach 22.9-24.8 MPa within 2h, the later strength can reach more than 70MPa without shrinkage, and the fluidity is improved by 40-60%.)

1. An application method of a support mortar coagulant prepared from coal gangue is characterized in that: the method comprises the following steps:

crushing industrial solid waste coal gangue in a crusher to obtain coal gangue particles with the particle size of about 5-20 mm, and dry-grinding the coal gangue particles to obtain coal gangue powder with the particle size of 100-500 mu m;

step (2) preparation of the support mortar coagulant: putting 20-30 parts of coal gangue powder, 150-160 parts of water, 240-300 parts of zirconia grinding body and 0.01-0.05 part of surface passivator in the step (1) into a wet grinding device for wet grinding for 40-60 min to prepare coal gangue slurry with the particle size of less than 0.3 mu m;

and (3): preparing support mortar, wherein the support mortar is prepared by the following steps in parts by weight:

25-45 parts of ordinary portland cement, 7-20 parts of water, 2-10 parts of a coal gangue coagulant, 40-60 parts of quartz sand, 0.1-0.2 part of a high-efficiency water reducing agent, 3-4.5 parts of an expanding agent, 0.03-0.2 part of a defoaming agent and 0.05-0.3 part of composite fibers are mixed and stirred to prepare the support mortar.

2. The method for using a setting accelerator for support mortar prepared from coal gangue according to claim 1, wherein the surface passivating agent is one of calcium carboxylate and calcium sulfonate.

3. The method for applying the setting accelerator for supporting mortar prepared from coal gangue according to claim 1, wherein the superplasticizer used is one of a polycarboxylic acid-based superplasticizer with a solid content of 40% and an HSB aliphatic superplasticizer with a solid content of 40%.

4. The application method of the support mortar accelerator prepared from coal gangue according to claim 1, wherein the coal gangue is solid waste residue left in coal mining and washing processes, and the coal gangue has pozzolanic activity.

5. The application method of the support mortar accelerator prepared from coal gangue according to claim 1, wherein the rotation speed of the wet grinding equipment is 300-400 r/min.

6. The method for using a setting accelerator for a support mortar prepared from coal refuse according to claim 1, wherein the swelling agent is one of a UEA swelling agent, an AEA swelling agent, and a HEA swelling agent.

7. The method for using a setting mortar accelerator made from coal gangue as claimed in claim 1, wherein the defoamer is an organic silicate defoamer.

8. The method for applying the setting mortar accelerator prepared from coal gangue according to claim 1, wherein the composite fiber is a polypropylene fiber.

Technical Field

The invention belongs to the field of building materials, and particularly relates to an application method of a support mortar coagulant prepared from coal gangue.

Background

At present, economic construction in China has not developed rapidly before, infrastructure construction develops forward in a wide situation, and therefore higher requirements are put forward for prolonging the service life of infrastructure construction engineering, especially for high-speed railways and railway passenger dedicated lines. In the bridge construction design of the railway passenger dedicated line, in order to prolong the service life of the bridge, the traditional box girder erection support anchoring construction process is changed, and early strength mortar is adopted for support anchoring. A large number of researches show that the traditional early-strength mortar material mainly has the defects of poor flowability of fresh slurry, low strength in slurry hardening, large shrinkage deformation, poor crack resistance, low later-stage rupture strength and the like. Most current abutment mortars use sulphoaluminate cement at a correspondingly increased cost.

CN108147754A discloses a support mortar prepared from cement, mineral powder, quartz sand, high-strength aggregate, ceramic microspheres, lithium bentonite, a retarding water reducer, a dispersing agent, an expanding agent, an early strength agent, a defoaming agent and composite fibers. The mortar has the characteristics of high flow state, good homogeneity, no bleeding, no layering, micro expansion, high early strength and the like, fully utilizes industrial waste residues such as steel slag, nickel slag and the like, and has good ecological environmental protection effect. But the composition is too complex as many as 12.

CN104370511A discloses a support mortar prepared from graded quartz sand, 42.5 sulphoaluminate cement, 42.5 ordinary silica water, a U-shaped expanding agent, a water reducing agent, a water-retaining agent, an early strength agent, a retarding agent and a defoaming agent. Said invented mortar slurry possesses high fluidity, short initial and final setting interval time and quick strength development. Due to the high price of sulphoaluminate cement on the market at present, the cost is increased correspondingly.

CN108164176A discloses a method for preparing a coagulant: weighing 4-6 parts of sodium metaaluminate, 3-5 parts of calcium oxide, 8-10 parts of modified sepiolite, 15-20 parts of mixed liquor, 10-12 parts of additive, 0.4-0.8 emulsifier and 0.2-0.3 times of dispersant in sequence; mixing sodium metaaluminate, calcium oxide and modified sepiolite in a mixer, stirring and mixing for 10-20 min at the temperature of 20-35 ℃ and the rotation speed of 300-380 r/min to obtain a mixed blank, mixing the mixed blank and the mixed solution in a mixer, adding an additive, an emulsifier and a dispersant into the mixer, stirring and mixing for 4-8 min at the rotation speed of 400-600 r/min to obtain the concrete accelerator. The setting accelerator of the above invention has excellent setting speed and strength, but the 1d strength is lower than 14MPa, and the early strength is lower.

CN109384412A discloses a method for preparing a coagulant: 10 to 25 percent of calcium salt, 0.4 to 5 percent of alcohol amine substance, 1 to 4 percent of anionic polymer and the balance of water, wherein the total amount is 100 percent. The coagulant prepared by the invention has good cooperativity with the polycarboxylate superplasticizer, can effectively shorten the setting time of concrete but not realize quick setting, and has smaller fluidity.

The problems of complex preparation, insufficient early strength, high cost and poor fluidity exist in the preparation of the support mortar in the prior art.

Disclosure of Invention

The invention aims to provide a support mortar coagulant prepared from coal gangue, which has the advantages of simple preparation, high early strength and low cost, and an application method thereof.

The invention aims at realizing the realization mode that the support mortar coagulant prepared by coal gangue and the application method thereof, wherein the preparation concrete materials of the coal gangue coagulant are calculated according to the parts by weight;

crushing industrial solid waste coal gangue in a crusher to obtain coal gangue particles with the particle size of about 5-20 mm, and dry-grinding the coal gangue particles to obtain coal gangue powder with the particle size of 100-500 mu m;

step (2) preparation of the support mortar coagulant: putting 20-30 parts of coal gangue powder, 150-160 parts of water, 240-300 parts of zirconia grinding body and 0.01-0.05 part of surface passivator in the step (1) into a wet grinding device for wet grinding for 40-60 min to prepare coal gangue slurry with the particle size of less than 0.3 mu m;

and (3): preparing support mortar, wherein the support mortar is prepared by the following steps in parts by weight:

25-45 parts of ordinary portland cement, 7-20 parts of water, 2-10 parts of a coal gangue coagulant, 40-60 parts of quartz sand, 0.1-0.2 part of a high-efficiency water reducing agent, 3-4.5 parts of an expanding agent, 0.03-0.2 part of a defoaming agent and 0.05-0.3 part of composite fibers are mixed and stirred to prepare the support mortar.

In the specific implementation process, the high-efficiency water reducing agent is one of a polycarboxylic acid high-performance water reducing agent with the solid content of 40% and an HSB aliphatic high-efficiency water reducing agent with the solid content of 40%.

In a specific implementation process, the swelling agent is one of UEA swelling agent, AEA swelling agent and HEA swelling agent.

In the specific implementation process, the defoaming agent is an organic silicon acid defoaming agent.

In the specific implementation process, the composite fiber is a polypropylene fiber.

In the specific implementation process, the coal gangue is solid waste residue left in the coal mining and coal washing processes, and the coal gangue has volcanic ash activity.

In the specific implementation process, the rotating speed of the wet grinding equipment is 300-400 r/min.

In a specific implementation process, the surface passivating agent is one of calcium carboxylate and calcium sulfonate. The purpose of adding the passivating agent is as follows: the particle micronization can be realized by wet grinding, but the specific surface area of the particle after the particle is micronized is increased sharply, and the extremely large specific surface area means that the particle has extremely large surface energy which is too large to cause the particle to be easy to agglomerate, so the particle is the balance of refining and agglomeration at the end of the wet grinding, and the surface passivating agent is added to passivate the surface of the nanoparticle to prevent agglomeration, and then the particle is further refined. The nanoparticles, once passivated, are not active. However, when the nanoparticles are added into cement, the strong alkaline environment generated by cement hydration can be desorption of the passivator adsorbed on the cement, and the process is 'activation'.

Beneficial effects

The solid waste coal gangue produced by coal gangue coal mine industry adopted by the invention has the chemical components of CaO and Al₂O₃、SiO₂、Fe₂O₃MgO, and the like. The coal gangue wet-grinding agent has an extremely important utilization prospect in the building material industry, and data obtained through tests show that the early strength of the coal gangue after wet grinding is added into cement mortar. Because the main components of the support mortar are alumina and silicon oxide which are all components with hydration activity, the surface glass body of the coal gangue after being ground by the wet method is damaged, Si and Al plasma are quickly dissolved out in cement slurry to show higher activity, and a water reducing agent, an early strength agent, an expanding agent and the like are supplemented, the prepared support mortar has high early strength, no bleeding, convenient construction and low cost.

According to the invention, after the coal gangue is subjected to wet grinding, the auxiliary cementing material coal gangue surface can adsorb water molecules to form a water film, the water film can reduce the surface energy of coal gangue particles and accelerate the dissolution of network glass on the coal gangue particle surface. In terms of wet-process pulverized coal ash, in the process of wet-process pulverizing and placing coal gangue for treatment, a vitreous network on the surface of the coal gangue is gradually depolymerized and a Si-O bond and an Al-O bond are broken, a large amount of metal ions such as Al, Si and the like are dissolved out, so that the activity of the coal gangue is increased, and in addition, after the coal gangue is subjected to wet-process pulverizing treatment, a silicon-oxygen tetrahedron is converted from high polymerization degree to low polymerization degree, so that the number of active reaction groups of the coal gangue is.

The wet-milled coal gangue can reach the nanometer level, plays a role of crystal nucleus in the cement hydration process and serves as a nucleation point of cement hydration products (such as ettringite and hydrated calcium silicate gel). Meanwhile, the nanometer coal gangue can fill gaps formed between cement particles and an interface, so that the particle grading of the cementing material is more reasonable, the porosity of cement hardened slurry is reduced, the compactness is increased, and the compressive strength of a cement matrix is improved.

Detailed Description

The present invention is described in detail below with reference to specific examples. Coal gangue adopted in the examples is commercially available; the cement is ordinary portland cement; the water is tap water; the water reducing agent is one of a polycarboxylic acid high-performance water reducing agent with solid content of 40% and an aliphatic high-efficiency water reducing agent with solid content of 40% of HSB, and is sold in the market; the used expanding agent is one of UEA expanding agent, AEA expanding agent and HEA expanding agent; the composite fiber is polypropylene fiber; the defoaming agent is organic silicon acid defoaming agent. The passivating agent is one of calcium carboxylate and calcium sulfonate

The first embodiment is as follows:

the composite material is prepared from the following raw materials in parts by weight:

putting industrial solid waste coal gangue into a crusher for crushing, wherein the particle size of the treated coal gangue is about 5-20 mm, then carrying out dry grinding on the crushed coal gangue to obtain coal gangue powder with the particle size of 100-500 mu m, and then mixing the obtained coal gangue powder, water and zirconium oxide according to the mass ratio of m₁:m₂:m₃Adding 0.03 part of surface passivator into a wet grinding device to perform wet grinding for 40-60 min to obtain coal gangue slurry with the particle size of less than 0.3 mu m, wherein the ratio of the surface passivator to the coal gangue is 1:5: 8.

The preparation of the support mortar comprises the following components in parts by weight: 39 parts of ordinary portland cement, 6 parts of coal gangue coagulant, 20 parts of 30-40 mesh quartz sand, 30 parts of 40-50 mesh quartz sand, 0.2 part of polycarboxylic acid high-efficiency water reducing agent, 4.55 parts of UEA expanding agent, 0.15 part of organic silicic acid defoaming agent and 0.1 part of polypropylene fiber. And stirring, molding and forming the proportioned materials, wherein the tested index parameters are shown in table 1.

The second embodiment:

putting industrial solid waste coal gangue into a crusher for crushingCrushing, wherein the particle size of the treated coal gangue is about 5-20 mm, dry-grinding the crushed coal gangue to obtain coal gangue powder with the particle size of 100-500 mu m, and mixing the obtained coal gangue powder, water and zirconia according to the mass ratio m₁:m₂:m₃Adding 0.03 part of surface passivator into a wet grinding device to perform wet grinding for 40-60 min to obtain coal gangue slurry with the particle size of less than 0.3 mu m, wherein the ratio of the surface passivator to the coal gangue is 1:5: 8.

The preparation of the support mortar comprises the following components in parts by weight: 43 parts of ordinary portland cement, 2 parts of coal gangue coagulant, 15 parts of 30-40 mesh quartz sand, 35 parts of 40-50 mesh quartz sand, 0.25 part of polycarboxylic acid high-efficiency water reducing agent, 4.45 parts of UEA expanding agent, 0.17 part of organic silicic acid defoaming agent and 0.13 part of polypropylene fiber. The proportioned materials were stirred, molded and molded, and the tested strengths are shown in table 1.

The third embodiment is as follows:

putting industrial solid waste coal gangue into a crusher for crushing, wherein the particle size of the treated coal gangue is about 5-20 mm, then carrying out dry grinding on the crushed coal gangue to obtain coal gangue powder with the particle size of 100-500 mu m, and then mixing the obtained coal gangue powder, water and zirconium oxide according to the mass ratio of m₁:m₂:m₃Adding 0.03 part of surface passivator into a wet grinding device to perform wet grinding for 40-60 min to obtain coal gangue slurry with the particle size of less than 0.3 mu m, wherein the ratio of the surface passivator to the coal gangue is 1:5: 8.

The preparation of the support mortar comprises the following components in parts by weight: 35 parts of ordinary portland cement, 10 parts of coal gangue coagulant, 15 parts of 30-40 mesh quartz sand, 35 parts of 40-50 mesh quartz sand, 0.15 part of polycarboxylic acid high-efficiency water reducing agent, 4.50 parts of UEA expanding agent, 0.25 part of organic silicic acid defoaming agent and 0.1 part of polypropylene fiber. The proportioned materials were stirred, molded and molded, and the tested strengths are shown in table 1.

Comparative example:

putting industrial solid waste coal gangue into a crusher for crushing, wherein the particle size of the treated coal gangue is about 5-20 mm, then carrying out dry grinding on the crushed coal gangue to obtain coal gangue powder with the particle size of 20-40 mu m, and then mixing the obtained coal gangue powder, water and zirconia according to the mass ratio m₁:m₂:m₃1:5:8, tableAnd adding 0.03 part of surface passivator into wet grinding equipment to carry out wet grinding for 40-60 min to obtain coal gangue slurry with the particle size of less than 0.3 mu m.

The preparation of the support mortar comprises the following components in parts by weight: 45 parts of ordinary portland cement, 0 part of coal gangue coagulant, 25 parts of 30-40 mesh quartz sand, 25 parts of 40-50 mesh quartz sand, 0.25 part of polycarboxylic acid high-efficiency water reducing agent, 4.45 parts of UEA expanding agent, 0.18 part of organic silicic acid defoaming agent and 0.12 part of polypropylene fiber. The proportioned materials are stirred, molded and formed, and the tested index parameters are shown in the following table.

TABLE 1

As can be seen from Table 1: the early strength of the support mortar prepared by adding the coagulant can reach 22.9-24.8 MPa within 2h, the strength is doubled compared with that of a control group, the later strength can reach more than 70MPa and is not shrunk, and the fluidity is improved by 40-60% compared with that of the control group.

The embodiments of the present invention are merely exemplary, and are not intended to limit the scope of the invention. It should be noted that those skilled in the art can make improvements and modifications without departing from the scope and spirit of the present invention.