CN110510893A - A kind of anti-oxidation barrier material and its preparation method and application - Google Patents

Abstract

The invention discloses an anti-oxidation barrier material and its preparation method and application. The anti-oxidation barrier material comprises tailings, a silicon-aluminum balancer and an alkali activator, and the mass ratio is 2-6:2:1. The preparation method of the anti-oxidation barrier material is to first grind the tailings, then add a silicon-aluminum balancer to the ground tailings and mix evenly, then add an alkali activator and mix evenly to obtain a mud. The application is in the anti-oxidation treatment of the tailings pond, and the anti-oxidation barrier material evenly covers the surface of the tailings pond to form an anti-oxidation barrier layer with a thickness of 3-5 cm. The invention realizes the isolation of tailings from external moisture and air, prevents oxygen in water and air from contacting with sulfide components, and prevents the oxidation process of tailings from the root; the invention uses all solid waste raw materials, and the main material is in situ Material collection and engineering application only need to bear the cost of labor and some machinery, and the economic investment is extremely low.

Description

A kind of anti-oxidation barrier material and its preparation method and application

technical field

The invention belongs to the technical field of tailings treatment, and in particular relates to an anti-oxidation barrier material and its preparation method and application.

Background technique

Mine tailings have always been one of the most intractable problems and a source of pollution that has caused major environmental problems. According to statistics, there are more than 1,500 large and medium-sized tailing ponds in China, and if various small tailing ponds are added, the total number exceeds 10,000. Its hazards are prominently manifested in acid tailings drainage, vegetation destruction, land degradation, desertification, dust pollution, and water pollution. Acidic leachate is the continuous reaction of sulfur-containing tailings with oxygen in the air, and the formation of sulfuric acid under the action of rainwater, which makes the pH of the tailings leachate acidic (pH=2-4), and the sulfides in the tailings can occur over time Continuous oxidation, and then continuous production of acidic wastewater. It can dissolve other associated metals in the tailings, such as Hg, Pb, As, Cd, etc., causing pollution to the downstream environment. Taking pyrite as an example, the chemical mechanism of acid wastewater formation is as follows:

Most of the tailings contain various colored, black, rare and precious, rare earth and non-metallic minerals, etc., which are valuable secondary mineral resources and need to be further developed and recycled. The oxidation and acid production of tailings will not only lead to the dissolution of valuable metals, but also cause a heavy burden on the environment. At present, there is no universally recognized and ideal method for the treatment of tailings farms. There are mainly lye neutralization, ex-situ treatment, or use of tailings to develop building materials to reduce tailings inventory, but these methods can only achieve temporary results. Effect, can not fundamentally solve the tailings oxidation problem.

At present, to deal with the oxidation problem of tailings ponds, there are mainly passivation treatment, chemical neutralization method, physical isolation method and phytoremediation, etc., for example, a method for in-situ protection of powdered metal sulfide tailings (CN106623354B), a An ecological restoration method for layered coverage of gold mine tailings (CN109731903A). The common problems of these methods are high input costs and poor long-term effects, and cannot completely and long-term solve the problems of tailings. In response to the above problems, it is imperative to find a product that is easy to implement, low in cost and good in effect.

Contents of the invention

The first object of the present invention is to provide an anti-oxidation barrier material.

The second object of the present invention is to provide a method for preparing an oxidation-resistant barrier material.

The third object of the present invention is to provide an application of an anti-oxidation barrier material in anti-oxidation treatment of tailings ponds.

The first object of the present invention is achieved in this way, including tailings, silicon-aluminum balancer and alkali activator, the mass ratio is 2~6:2:1.

The second purpose of the present invention is achieved by first grinding the tailings, then adding a silicon-aluminum balancer to the ground tailings and mixing uniformly, then adding an alkali activator and mixing uniformly to obtain a slime, namely Can.

The third object of the present invention is achieved by uniformly covering the surface of the tailings pond with the anti-oxidation barrier material to form an anti-oxidation barrier layer with a thickness of 3-5 cm.

Compared with the prior art, the present invention has the following technical effects:

1. The anti-oxidation barrier material of the present invention is prepared through the proportioning of tailings, silicon-aluminum balancer and alkali activator, and the Si-O bond in the network structure of the silicon ^- aluminum material will be broken rapidly by using OH under high pH conditions, thereby The silicon-rich phase is quickly dissolved, and at the same time, some aluminum that replaces silicon in the silicon-rich phase will also dissolve and repolymerize, and finally quickly form a hardened barrier layer with high hardness and low water permeability coefficient, so as to realize the separation of tailings and External moisture and air are isolated to prevent oxygen in water and air from contacting with sulfide components, and to prevent the oxidation process of tailings from the root;

2. The anti-oxidation barrier material of the present invention all utilizes solid waste raw materials, and the main material is obtained from the original site. Engineering applications only need to bear labor and some mechanical costs, and the economic investment is extremely low;

3. The anti-oxidation barrier material of the present invention uses the red mud solution as the alkali stimulator, which not only effectively utilizes the alkalinity of the red mud, but also rationally utilizes solid waste resources, and reduces the pressure of the red mud itself on the environment. Particularity, the slow-release alkali that is difficult to dissolve in the crystal lattice can be used as a long-term acid-base buffer for tailings ponds;

4. When the anti-oxidation barrier material of the present invention is used in the anti-oxidation treatment of tailings ponds, it does not need high-temperature curing, and only needs normal temperature waterproof curing to form, which simplifies the process flow and reduces maintenance costs; the anti-oxidation barrier material in the tailings pond The anti-oxidation barrier layer formed on the surface ensures low water permeability and high hardness at the same time. It can not only provide long-term isolation protection for the tailings pond, but also cover soil cultivation on the barrier layer, and at the same time, it is beneficial to the ecological protection of the tailings pond. Restoration also has the function of preventing dust and reinforcing the old reservoir body, reducing the dust pollution caused by the tailings reservoir, and reducing the threat of reservoir collapse.

Detailed ways

The present invention will be further described below in conjunction with the examples, but the present invention is not limited in any way, and any transformation or substitution made based on the teaching of the present invention belongs to the protection scope of the present invention.

The invention includes tailings, silicon-aluminum balancer and alkali activator, and the mass ratio is 2-6:2:1.

Preferably, the anti-oxidation barrier material includes tailings, a silicon-aluminum balancer and an alkali activator, with a mass ratio of 3-5:2:1.

The reaction mechanism of the anti-oxidation barrier material is:

Chemical hydration reaction:

Physical electrostatic reaction:

Polycondensation reactions in which ion pairs condense with each other:

.

Preferably, the fineness modulus of the tailings is less than 3.0, and the fineness modulus is calculated by the following formula:

MX=[(A0.15+A0.3+A0.6+A1.18+A2.36)-5A4.75]/(100-A4.75),

Among them, MX is the fineness modulus, A0.15 is the cumulative sieve percentage of particles with a particle size of 0.15mm, A0.3 is the cumulative sieve percentage of particles with a particle size of 0.30mm, and A0.6 is the cumulative sieve percentage of particles with a particle size of 0.60mm. Remaining percentage, A1.18 is the cumulative sieving percentage of particles with a particle size of 1.18mm, A2.36 is the cumulative sieved percentage of particles with a particle size of 2.36mm, and A4.75 is the cumulative sieved percentage of particles with a particle size of 4.75mm.

Preferably, the silicon-aluminum balancer includes silica fume and fly ash, with a mass ratio of 1:2.5~3.5.

Preferably, the alkali activator is a red mud solution with a concentration not lower than 10 g/L.

The preparation method of the anti-oxidation barrier material firstly grinds the tailings, then adds a silicon-aluminum balancer to the ground tailings and mixes them uniformly, then adds an alkali activator and mixes them uniformly to obtain a sludge, which can be .

In the application of the anti-oxidation barrier material in the anti-oxidation treatment of the tailings pond, the anti-oxidation barrier material is evenly covered on the surface of the tailings pond to form an anti-oxidation barrier layer with a thickness of 3-5 cm.

Preferably, maintenance is also included, and the maintenance is to prevent rain under normal temperature conditions and to stand still for at least 5 days after covering.

The present invention will be further described below in conjunction with Embodiment 1 to Embodiment 42.

Example 1

Anti-oxidation barrier materials, including tailings, silicon-aluminum balancer and alkali activator, the mass ratio is 2:2:1.

Example 2

Anti-oxidation barrier materials, including tailings, silicon-aluminum balancer and alkali activator, the mass ratio is 6:2:1.

Example 3

Anti-oxidation barrier materials, including tailings, silicon-aluminum balancer and alkali activator, the mass ratio is 3:2:1.

Example 4

Anti-oxidation barrier materials, including tailings, silicon-aluminum balancer and alkali activator, the mass ratio is 5:2:1.

Example 5

Anti-oxidation barrier materials, including tailings, silicon-aluminum balancer and alkali activator, the mass ratio is 4:2:1.

Example 6

The anti-oxidation barrier material includes tailings, a silicon-aluminum balancer and an alkali activator, the mass ratio of which is 2:2:1, and the fineness modulus of the tailings is 2.99.

Example 7

The anti-oxidation barrier material includes mine tailings, a silicon-aluminum balancer and an alkali activator with a mass ratio of 6:2:1, and the fineness modulus of the tailings is 2.7.

Example 8

The anti-oxidation barrier material includes tailings, a silicon-aluminum balancer and an alkali activator, the mass ratio of which is 3:2:1, and the fineness modulus of the tailings is 2.5.

Example 9

The anti-oxidation barrier material includes tailings, a silicon-aluminum balancer and an alkali activator, the mass ratio of which is 5:2:1, and the fineness modulus of the tailings is 0.1.

Example 10

The anti-oxidation barrier material includes tailings, a silicon-aluminum balancer and an alkali activator, the mass ratio is 4:2:1, and the fineness modulus of the tailings is 1.5.

Example 11

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and alkali activator, the mass ratio is 2:2:1, the fineness modulus of the tailings is 2.99, the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:2.5.

Example 12

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and alkali activator, the mass ratio is 6:2:1, the fineness modulus of the tailings is 2.7, and the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1: 3.5.

Example 13

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and alkali activator, the mass ratio is 3:2:1, the fineness modulus of the tailings is 2.5, and the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:2.5.

Example 14

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and alkali activator, the mass ratio is 5:2:1, the fineness modulus of the tailings is 0.1, and the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:3.5.

Example 15

The anti-oxidation barrier material includes tailings, silicon-aluminum balancer and alkali activator, the mass ratio is 4:2:1, the fineness modulus of the tailings is 1.5, and the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:3.

Example 16

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and red mud solution, the mass ratio is 2:2:1, the fineness modulus of the tailings is 2.99, the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:2.5, and the concentration of red mud solution is 10g/L.

Example 17

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and red mud solution, the mass ratio is 6:2:1, the fineness modulus of the tailings is 2.7, the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1: 3.5, and the concentration of red mud solution is 12g/L.

Example 18

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and red mud solution, the mass ratio is 3:2:1, the fineness modulus of the tailings is 2.5, and the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:2.5, and the concentration of red mud solution is 15g/L.

Example 19

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and red mud solution, the mass ratio is 5:2:1, the fineness modulus of the tailings is 0.1, and the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:3.5, and the red mud solution concentration is 18g/L.

Example 20

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and red mud solution, the mass ratio is 4:2:1, the fineness modulus of the tailings is 1.5, and the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:3, and the concentration of red mud solution is 20g/L.

Example 21

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and red mud solution, the mass ratio is 2:2:1, the fineness modulus of the tailings is 2.5, the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:3.

Example 22

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and red mud solution, the mass ratio is 4:2:1, the fineness modulus of the tailings is 2.5, the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:3.

Example 23

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and red mud solution, the mass ratio is 6:2:1, the fineness modulus of the tailings is 2.5, and the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:3.

Example 24

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and red mud solution, the mass ratio is 2:2:1, the fineness modulus of the tailings is 3.0, the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:3.

Example 25

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and red mud solution, the mass ratio is 4:2:1, the fineness modulus of the tailings is 3.0, the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:3.

Example 26

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and red mud solution, the mass ratio is 6:2:1, the fineness modulus of the tailings is 3.0, and the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:3.

Example 27

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and red mud solution, the mass ratio is 2:2:1, the fineness modulus of the tailings is 2.7, the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:3.

Example 28

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and red mud solution, the mass ratio is 4:2:1, the fineness modulus of the tailings is 2.7, the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:3.

Example 29

Anti-oxidation barrier material, including tailings, silicon-aluminum balancer and red mud solution, the mass ratio is 6:2:1, the fineness modulus of the tailings is 2.7, the silicon-aluminum balancer includes silica fume, powder Coal ash, the mass ratio is 1:3.

Example 30

According to the anti-oxidation barrier material of Example 1, the preparation method of the anti-oxidation barrier material, first grind the tailings, then add a silicon-aluminum balancer to the ground tailings and mix uniformly, then add an alkali activator and mix uniformly , to get slime.

Example 31

According to the anti-oxidation barrier material of Example 7, the preparation method of the anti-oxidation barrier material, the tailings are first ground until the fineness modulus of the tailings is 2.7, and then the silicon-aluminum balancer is added to the tailings after the grinding process and Mix evenly, then add alkali activator and mix evenly to get mud.

Example 32

According to the anti-oxidation barrier material of Example 13, the preparation method of the anti-oxidation barrier material, first grind the tailings until the fineness modulus of the tailings is 2.5, then add a silicon-aluminum balancer to the tailings after the grinding treatment and Mix evenly, then add alkali activator and mix evenly to get a muddy substance;

The prepared slime anti-oxidation barrier material is evenly covered on the surface of the tailings pond to form an anti-oxidation barrier layer with a thickness of 3 cm. After covering, it is protected from rain under normal temperature conditions and allowed to stand for 5 days.

Example 33

According to the anti-oxidation barrier material in Example 20, the preparation method of the anti-oxidation barrier material, first grind the tailings until the fineness modulus of the tailings is 1.5, then add a silicon-aluminum balancer to the ground tailings and Mix evenly, then add the red mud solution and mix evenly to get a muddy substance;

The prepared slime anti-oxidation barrier material was evenly covered on the surface of the tailings pond to form an anti-oxidation barrier layer with a thickness of 3 cm. After covering, it was protected against rain under normal temperature conditions and stood for 6 days.

Example 34

According to the anti-oxidation barrier material of Example 21, the preparation method of the anti-oxidation barrier material, first grind the tailings until the fineness modulus of the tailings is 2.5, then add a silicon-aluminum balancer to the ground tailings and Mix evenly, then add the red mud solution and mix evenly to get a muddy substance;

The prepared slime anti-oxidation barrier material is evenly covered on the surface of the tailings pond to form an anti-oxidation barrier layer with a thickness of 3 cm. After covering, it is protected from rain under normal temperature conditions and allowed to stand for 7 days.

Example 35

According to the anti-oxidation barrier material of Example 22, the preparation method of the anti-oxidation barrier material, first grind the tailings until the fineness modulus of the tailings is 2.5, then add a silicon-aluminum balancer to the ground tailings and Mix evenly, then add the red mud solution and mix evenly to get a muddy substance;

The prepared slime anti-oxidation barrier material is evenly covered on the surface of the tailings pond to form an anti-oxidation barrier layer with a thickness of 5 cm. After covering, it is protected from rain under normal temperature conditions and allowed to stand for 7 days.

Example 36

According to the anti-oxidation barrier material of Example 23, the preparation method of the anti-oxidation barrier material, first grind the tailings until the fineness modulus of the tailings is 2.5, then add a silicon-aluminum balancer to the ground tailings and Mix evenly, then add the red mud solution and mix evenly to get a muddy substance;

The prepared slime anti-oxidation barrier material is evenly covered on the surface of the tailings pond to form an anti-oxidation barrier layer with a thickness of 4 cm. After covering, it is protected from rain under normal temperature conditions and allowed to stand for 7 days.

Example 37

According to the anti-oxidation barrier material of Example 24, the preparation method of the anti-oxidation barrier material, first grind the tailings until the fineness modulus of the tailings is 3.0, then add a silicon-aluminum balancer to the ground tailings and Mix evenly, then add the red mud solution and mix evenly to get a muddy substance;

The prepared slime anti-oxidation barrier material is evenly covered on the surface of the tailings pond to form an anti-oxidation barrier layer with a thickness of 3 cm. After covering, it is protected from rain under normal temperature conditions and allowed to stand for 7 days.

Example 38

According to the anti-oxidation barrier material of Example 25, the preparation method of the anti-oxidation barrier material, first grind the tailings until the fineness modulus of the tailings is 3.0, then add a silicon-aluminum balancer to the ground tailings and Mix evenly, then add the red mud solution and mix evenly to get a muddy substance;

The prepared slime anti-oxidation barrier material is evenly covered on the surface of the tailings pond to form an anti-oxidation barrier layer with a thickness of 5 cm. After covering, it is protected from rain under normal temperature conditions and allowed to stand for 7 days.

Example 39

According to the anti-oxidation barrier material of Example 26, the preparation method of the anti-oxidation barrier material, first grind the tailings until the fineness modulus of the tailings is 3.0, then add a silicon-aluminum balancer to the ground tailings and Mix evenly, then add the red mud solution and mix evenly to get a muddy substance;

The prepared slime anti-oxidation barrier material is evenly covered on the surface of the tailings pond to form an anti-oxidation barrier layer with a thickness of 3 cm. After covering, it is protected from rain under normal temperature conditions and allowed to stand for 7 days.

Example 40

According to the anti-oxidation barrier material of Example 27, the preparation method of the anti-oxidation barrier material, first grind the tailings until the fineness modulus of the tailings is 2.7, then add a silicon-aluminum balancer to the ground tailings and Mix evenly, then add the red mud solution and mix evenly to get a muddy substance;

The prepared slime anti-oxidation barrier material is evenly covered on the surface of the tailings pond to form an anti-oxidation barrier layer with a thickness of 5 cm. After covering, it is protected from rain under normal temperature conditions and allowed to stand for 7 days.

Example 41

According to the anti-oxidation barrier material in Example 28, the preparation method of the anti-oxidation barrier material, first grind the tailings until the fineness modulus of the tailings is 2.7, then add a silicon-aluminum balancer to the ground tailings and Mix evenly, then add the red mud solution and mix evenly to get a muddy substance;

The prepared slime anti-oxidation barrier material is evenly covered on the surface of the tailings pond to form an anti-oxidation barrier layer with a thickness of 4 cm. After covering, it is protected from rain under normal temperature conditions and allowed to stand for 7 days.

Example 42

According to the anti-oxidation barrier material of Example 29, the preparation method of the anti-oxidation barrier material, first grind the tailings until the fineness modulus of the tailings is 2.7, then add a silicon-aluminum balancer to the ground tailings and Mix evenly, then add the red mud solution and mix evenly to get a muddy substance;

The prepared slime anti-oxidation barrier material is evenly covered on the surface of the tailings pond to form an anti-oxidation barrier layer with a thickness of 4 cm. After covering, it is protected from rain under normal temperature conditions and allowed to stand for 7 days.

The tailings ponds in Examples 34 to 42 belong to historical tin tailings ponds, which are stacked in the open air all year round. The sulfur element in the tailings is easily oxidized by air, and reacts with moisture in the environment to form sulfuric acid to form acidic leachate; Examples 34 to 42 After the tailings were treated for 7 days, the water permeability coefficient, hardness and acid erosion resistance of the anti-oxidation barrier layer were tested according to conventional methods. The test results are shown in Table 1.

Table 1 Test results of anti-oxidation barrier layer

It can be seen from Table 1 that the present invention has better waterproof, acid resistance and hardness performance, and the water seepage test pieces are not penetrated, which can effectively block the infiltration of water; the hardness and acid erosion resistance are excellent, and can carry a sufficient amount of soil for cultivation and greening And long-term anti-acid and anti-oxidation protection.

Claims (8)

1. a kind of anti-oxidation barrier material, it is characterised in that including tailing, sial poising agent and alkali-activator, mass ratio is 2 ~ 6: 2:1。

2. anti-oxidation barrier material according to claim 1, it is characterised in that including tailing, sial poising agent and alkali-activated carbonatite Agent, mass ratio are 3 ~ 5:2:1.

3. anti-oxidation barrier material according to claim 1 or claim 2, it is characterised in that the fineness modulus of the tailing less than 3.0, The fineness modulus is calculated by following formula:

MX=[(A0.15+A0.3+A0.6+A1.18+A2.36) -5A4.75]/(100-A4.75),

Wherein MX is fineness modulus, and A0.15 is particle accumulated retained percentage on partial size 0.15mm, and A0.3 is on partial size 0.30mm Particle accumulated retained percentage, A0.6 are particle accumulated retained percentage on partial size 0.60mm, and A1.18 is partial size 1.18mm Shang Grain accumulated retained percentage, A2.36 are particle accumulated retained percentage on partial size 2.36mm, and A4.75 is partial size 4.75mm Shang Grain accumulated retained percentage.

4. anti-oxidation barrier material according to claim 1 or claim 2, it is characterised in that the sial poising agent includes silicon ash, powder Coal ash, mass ratio are 1:2.5 ~ 3.5.

5. anti-oxidation barrier material according to claim 1 or claim 2, it is characterised in that the alkali-activator is red mud solution, dense Degree is not less than 10g/L.

6. a kind of preparation method of the anti-oxidation barrier material any according to claim 1 ~ 5, it is characterised in that first by tailing Grinding, then sial poising agent is added into the tailing after milled processed and is uniformly mixed, adds alkali-activator and is uniformly mixed, Obtain purees.

7. a kind of application of anti-oxidation barrier material any according to claim 1 ~ 5 in the anti-oxidation processing of Tailings Dam, It is characterized in that the anti-oxidation barrier material uniform fold forming anti-oxidation barrier layer on Tailings Dam surface, with a thickness of 3 ~ 5cm。

8. applying according to claim 7, it is characterised in that further include maintenance, after the maintenance is covering, under normal temperature condition Rain-proof and stand at least 5 days.