CN107540302B

CN107540302B - Cementing material for mine filling and filling slurry containing same

Info

Publication number: CN107540302B
Application number: CN201710691642.4A
Authority: CN
Inventors: 陈忠平; 陈锡麟; 李鹏; 潘敏尧; 何威; 冯波宇; 伍航宇; 黄小波; 黄威龙; 张善硕; 赵泽民
Original assignee: Guyan Technology Development Co ltd
Current assignee: Guyan Technology Development Co ltd
Priority date: 2017-08-14
Filing date: 2017-08-14
Publication date: 2020-05-15
Anticipated expiration: 2037-08-14
Also published as: CN107540302A

Abstract

The invention discloses a cementing material for mine filling and filling slurry containing the same. The cementing material for mine filling comprises the following raw materials in parts by mass: 40-65 parts of phosphogypsum, 18-25 parts of loess, 10-22 parts of slag, 5-15 parts of steel slag and 0.1-0.8 part of water reducing agent. The slurry for mine filling comprises the cementing material for mine filling, cement and water. The invention designs and develops a cementing material for mine filling, which takes phosphogypsum as a main raw material and loess as an auxiliary material, aiming at the requirement of a mine filling gelling agent. Compared with the existing cement, the filling slurry prepared by the cementing material of the invention has better strength than the existing cement, and simultaneously, the filling slurry of the invention completely meets the fluidity required by mine filling. The filling slurry of the invention uses loess to reduce the filling cost, not only can completely replace cement, but also is beneficial to consuming a large amount of accumulated phosphogypsum and protecting the environment.

Description

Cementing material for mine filling and filling slurry containing same

Technical Field

The invention relates to a cementing material for mine filling and filling slurry containing the cementing material.

Background

Phosphogypsum is an industrial byproduct of phosphoric acid wet-process production of phosphorus chemical enterprises, and about 5 tons of phosphogypsum are produced per 1 ton of phosphoric acid. With the rapid development of the phosphorus chemical industry in China, the annual byproduct phosphogypsum exceeds 4000 million tons, and the accumulated phosphogypsum exceeds about 2 hundred million tons. For various reasons, the resource utilization rate of the phosphogypsum in China is less than 15 percent at present, the rest part is used as solid waste to be accumulated or buried, a large amount of land is occupied, and the environment is seriously polluted, so that the resource utilization of the phosphogypsum is accelerated and delayed.

On the other hand, the mining industry forms a large amount of goafs while asking for resources, and the goafs collapse or collapse unstably, so that a large amount of land and vegetation are damaged, and even safety accidents are caused. Meanwhile, a large amount of tailing sand generated by mining has extremely fine particles and large component fluctuation, and is difficult to utilize, and the tailing sand which cannot be utilized is accumulated into a tailing mountain, so that not only is the resource greatly wasted, but also the environment is greatly polluted. The mining of the mineral deposit by the filling method is the most reliable technical support for protecting the earth surface from collapse and realizing the coordinated development of the mining industry and the environment. And the cheap mine waste tailing sand is applied to mine filling in a large quantity, so that raw materials of the mine filling material are provided, the problems that the mine industrial waste pollutes the environment and occupies cultivated land are solved, and the method has great significance. At present, most filling cementing agents used by mine filling mining methods are still silicate cement, and special gelling agents suitable for mine filling characteristics are rare.

The loess plateau region is a region where loess is most distributed on the earth and is influenced by the loess, and the loess is widely distributed in the middle and western regions of China, including the Qinghai, Shaanxi, Shanxi, inner Mongolia, Henan, Hebei and the like. Loess is mostly considered to be formed by weathered sediments, and is formed later, loose and porous in nature, poor in cohesive force, fine in particles and belongs to silt in sandy soil. The loess has the characteristics of low price and easy obtainment, and the filling material which meets the filling requirement of the mine goaf is developed by utilizing the advantages of the natural resources, taking the loess as an auxiliary material and using the phosphogypsum, thereby having important significance.

Disclosure of Invention

The invention aims to provide a cementing material for mine filling and filling slurry containing the cementing material.

The technical scheme adopted by the invention is as follows:

a cementing material for mine filling comprises the following raw materials in parts by mass: 40-65 parts of phosphogypsum, 18-25 parts of loess, 10-22 parts of slag, 5-15 parts of steel slag and 0.1-0.8 part of water reducing agent.

The particle size of loess is less than 85 μm.

The slag is blast furnace water-quenched slag.

The water reducing agent is at least one of lignosulfonate water reducing agents, naphthalene water reducing agents, melamine water reducing agents, sulfamate water reducing agents, fatty acid water reducing agents and polycarboxylic acid water reducing agents.

The slurry for mine filling comprises the cementing material for mine filling, cement and water.

In the slurry, the mass ratio of the cementing material to the cement is 1: (3-8).

In the slurry, the cement is 42.5 or 42.5R type cement.

The water content of the slurry is 30-40 wt%.

The invention has the beneficial effects that:

the invention designs and develops a cementing material for mine filling, which takes phosphogypsum as a main raw material and loess as an auxiliary material, aiming at the requirement of a mine filling gelling agent. Compared with the existing cement, the filling slurry prepared by the cementing material of the invention has better strength than the existing cement, and simultaneously, the filling slurry of the invention completely meets the fluidity required by mine filling. The filling slurry of the invention uses loess to reduce the filling cost, not only can completely replace cement, but also is beneficial to consuming a large amount of accumulated phosphogypsum and protecting the environment.

Detailed Description

Preferably, the cementing material for mine filling comprises the following raw materials in parts by mass: 48-60 parts of phosphogypsum, 19-21 parts of loess, 11.5-19.5 parts of slag, 6-12 parts of steel slag and 0.2-0.5 part of water reducing agent.

Preferably, the chemical composition of phosphogypsum is: SO (SO)₃35 to 40 weight percent of CaO, 28 to 32 weight percent of SiO₂The content is 7 wt% -10 wt%, P₂O₅1 to 1.5 weight percent of Al₂O₃0.8 wt% -1.3 wt% of Fe₂O₃The content is 0.5 wt% -1.0 wt%, and the rest is loss on ignition.

The loess is preferably loess from Shanxi region, and is sieved before use to obtain loess with particle size less than 85 μm.

Preferably, the loess has a main chemical composition of: SiO 2₂53 to 58 weight percent of Al₂O₃25 to 30 weight percent of Fe₂O₃2.5 to 3.5 weight percent of TiO₂The content is 1 wt% -2 wt%.

Preferably, the slag is blast furnace water-quenched slag.

Preferably, the chemical composition of the slag is: CaO content of 35-39 wt%, SiO₂28 to 31 weight percent of Al₂O₃13 to 16 weight percent of MgO, 8 to 10 weight percent of Fe₂O₃The content is 3 to 5 weight percent, and the rest is loss on ignition.

Preferably, the steel slag has the chemical composition as follows: CaO content of 38 wt% -41 wt%, Fe₂O₃16 to 18 weight percent of SiO₂13 to 15 weight percent of MgO, 7 to 9 weight percent of Al₂O₃6 to 8 weight percent of SO₃The content of (A) is 6 wt% -8 wt%, and the balance is loss on ignition.

Preferably, the water reducing agent is at least one of a lignosulfonate water reducing agent, a naphthalene water reducing agent, a melamine water reducing agent, a sulfamate water reducing agent, a fatty acid water reducing agent and a polycarboxylic acid water reducing agent.

Preferably, the mass ratio of the cementing material to the cement in the slurry is 1: (3-8); further preferably, the mass ratio of the cementing material to the cement is 1: 4.

preferably, the cement in the slurry is 42.5 or 42.5R-type cement; more preferably, the cement is 42.5 type cement.

Preferably, the water content of the slurry is 30 wt% to 40 wt%; further preferably, the water content of the slurry is 35 wt%.

The main component of phosphogypsum is dihydrate gypsum, which does not have gelling property per se. However, under the condition of proper alkalinity (steel slag), the gypsum and some industrial waste residues with latent hydraulicity can generate hydration reaction and generate stable hydration products. Loess has the characteristics of looseness, porosity, fine particles and large surface area, is beneficial to the adsorption and dispersion of various raw materials, and forms a more stable hydration product. Meanwhile, the loess has wide sources and low price, so that the production cost of the cementing material can be reduced. The ardealite without calcination treatment is used as main material and loess is used as supplementary material, and through adding blast furnace slag and small amount of alkali activator, one kind of hydraulic cementing material with low power consumption and high strength is prepared.

The present invention will be described in further detail with reference to specific examples.

Example 1:

the raw material composition of a cement for mine filling is shown in table 1.

Table 1 cementitious material of example 1

Raw materials	Mass portion of
		Phosphogypsum	48
Yellow soil	20
		Slag of mine	19.5
Steel slag	12
		Water reducing agent	0.5

Example 2:

the raw material composition of a cement for mine filling is shown in table 2.

Table 2 cementitious material of example 2

Example 3:

the raw material composition of a cement for mine filling is shown in table 3.

Table 3 cement of example 3

Raw materials	Mass portion of
		Phosphogypsum	54
Yellow soil	20
		Slag of mine	17.8
Steel slag	8
		Water reducing agent	0.2

Example 4

The raw material composition of the cementing material for mine filling is shown in Table 4.

Table 4 example 4 cementitious Material

Raw materials	Mass portion of
		Phosphogypsum	56
Yellow soil	20
		Slag of mine	11.5
Steel slag	12
		Water reducing agent	0.5

Example 5:

the raw material composition of a cement for mine filling is shown in table 5.

Table 5 cement of example 5

In examples 1 to 5, the chemical composition of the used phosphogypsum is as follows: SO (SO)₃38.9 percent of CaO, 30.4 percent of SiO₂Content of 8.7%, P₂O₅Content of 1.3%, Al₂O₃Content of 1.1% Fe₂O₃The content is 0.7 percent, and the rest is loss on ignition; the particle size of the loess is less than 85 μm, and the chemical composition is as follows: SiO 2₂55.6% of Al₂O₃28.2% Fe₂O₃3.02% of TiO₂1.28 percent of the total trace elements, 8.7 percent of the loss on ignition and the balance of trace elements; the slag is blast furnace water quenching slag, and the chemical composition of the slag is as follows: CaO content 38.2%, SiO₂30.5% of Al₂O₃15.3% of MgO, 9.7% of Fe₂O₃The content is 4.3 percent, and the rest is loss on ignition; the chemical composition of the steel slag is as follows: CaO content 40.3%, Fe₂O₃Content of 17.5% SiO₂14.8% of MgO 8.3% of Al₂O₃The content of SO is 7.5%₃The content of (A) is 7.1 percent, and the balance is ignition loss; the water reducing agent is a naphthalene water reducing agent.

The cementing material and the filling slurry of the invention are prepared by the following method:

1) weighing phosphogypsum, loess, slag and steel slag according to a ratio, and adding into a stirring barrel;

2) sealing the stirring barrel, and stirring for 5 minutes by using a stirrer;

3) adding a proportional water reducing agent after stirring;

4) according to the ash-sand ratio (mass ratio of cementing material to 42.5 type ordinary portland cement) of 1: adding water with the mass concentration of 4 to 65 percent, and continuously stirring for 5 minutes to ensure that the mixture is completely and uniformly stirred;

5) taking a proper amount of evenly stirred slurry, and carrying out a fluidity test by adopting a micro slump constant instrument method according to GB/T8077-;

6) pouring the fully and uniformly mixed slurry into a triple die with the thickness of 40mm x 160mm, scraping the surface by a scraper, and putting the triple die into a curing box;

7) after the test sample has a certain strength, the mold is removed, and the test sample is maintained in an environment with the temperature of 20 +/-2 ℃ and the relative humidity of 95% for a specified age, and strength measurement is carried out for 3 days, 7 days and 28 days.

And meanwhile, making a comparative example: the conventional gelatinizing agent for mines, common type 42.5 cement purchased in the market is used, and the weight ratio of the lime to the sand is 1: 4, a slurry concentration of 65% was prepared under the same conditions as in examples.

According to actual production experience, the technical indexes required by mine filling are as follows: the fluidity value is not less than 200mm, the 3-day strength is more than 0.5MPa, the 7-day strength is more than 2.5MPa, and the 28-day strength is not less than 6 MPa.

The compression resistance results of examples 1-5 and comparative example are shown in Table 6.

TABLE 6 compression resistance results for examples and comparative examples

As can be seen from Table 6, the fill slurries of the present invention have overall better strengths at 3 days, 7 days and 28 days than conventional cement cements.

The fluidity results of examples 1 to 5 and comparative example are shown in table 7.

TABLE 7 fluidity results of examples and comparative examples

	Fluidity (mm)
		Example 1	235
Example 2	238
		Example 3	242
Example 4	247
		Example 5	231
Comparative example	245

As can be seen from Table 7, the filling slurry of the present invention has a fluidity substantially close to that of the existing cement. In conclusion, the filling slurry can completely replace the existing cement and is used for filling mines.

Claims

1. A cementing material for mine filling is characterized in that: the composite material is prepared from the following raw materials in parts by mass: 40-65 parts of phosphogypsum, 18-25 parts of loess, 10-22 parts of slag, 5-15 parts of steel slag and 0.1-0.8 part of water reducing agent;

the phosphogypsum isThe chemical composition of (A) is as follows: SO (SO)₃35 to 40 weight percent of CaO, 28 to 32 weight percent of SiO₂The content is 7 wt% -10 wt%, P₂O₅1 to 1.5 weight percent of Al₂O₃0.8 wt% -1.3 wt% of Fe₂O₃The content is 0.5 wt% -1.0 wt%, and the rest is loss on ignition;

the particle size of the loess is less than 85 μm; the main chemical composition of the loess is as follows: SiO 2₂53 to 58 weight percent of Al₂O₃25 to 30 weight percent of Fe₂O₃2.5 to 3.5 weight percent of TiO₂The content is 1 wt% -2 wt%;

the slag is blast furnace water-quenched slag; the chemical composition of the slag is as follows: CaO content of 35-39 wt%, SiO₂28 to 31 weight percent of Al₂O₃13 to 16 weight percent of MgO, 8 to 10 weight percent of Fe₂O₃The content is 3 to 5 weight percent, and the rest is the loss on ignition;

the steel slag comprises the following chemical components: CaO content of 38 wt% -41 wt%, Fe₂O₃16 to 18 weight percent of SiO₂13 to 15 weight percent of MgO, 7 to 9 weight percent of Al₂O₃6 to 8 weight percent of SO₃The content of (A) is 6 wt% -8 wt%, and the balance is loss on ignition.

2. The cementing material for mine filling according to claim 1, wherein: the water reducing agent is at least one of lignosulfonate water reducing agents, naphthalene water reducing agents, melamine water reducing agents, sulfamate water reducing agents, fatty acid water reducing agents and polycarboxylic acid water reducing agents.

3. A slurry for mine filling, characterized in that: comprising the cementing material for mine filling of claim 1, cement and water.

4. The slurry for mine filling according to claim 3, wherein: the mass ratio of the cementing material to the cement is 1: (3-8).

5. The slurry for mine filling according to claim 4, wherein: the cement is 42.5 or 42.5R type cement.

6. The slurry for mine filling according to claim 3, wherein: the water content of the slurry is 30-40 wt%.