CN113480211A

CN113480211A - Ternary coupling excited tailing powder and product thereof

Info

Publication number: CN113480211A
Application number: CN202110794427.3A
Authority: CN
Inventors: 金小刚; 窦顺珍; 苏磊
Original assignee: Beijing Ronglu Material Technology Co ltd
Current assignee: Beijing Ronglu Material Technology Co ltd
Priority date: 2021-07-14
Filing date: 2021-07-14
Publication date: 2021-10-08

Abstract

The invention belongs to a ternary coupling excited tailing powder, which is characterized in that: the preparation method comprises the following steps: s1, grinding the tailings containing the silicon and aluminum materials and 0.1-5 mol/L of chemical exciting agent together, and adding an aluminum correction material to mix to prepare a mixture, wherein the ratio of Si to Al of the mixture is less than or equal to 1: 5; s2, placing the mixture and silicon carbide balls in a ball mill with a microwave generator for ball milling, wherein the ball-to-material ratio of the silicon carbide balls to the mixture is 20: 1-20: 5; and S3, activating the mixture by turning on a microwave generator while performing ball milling, wherein the microwave heating temperature is 500-900 ℃, and obtaining the active tailing powder after activation. The invention has the beneficial effects that: according to the technical scheme, the dissolution rate of the silico-aluminum material in the tailings is improved through a chemical method, and the crystallinity of the silico-aluminum material in the tailings is reduced through a mechanical method, so that the silico-aluminum material is changed into an amorphous state with considerable activity under the action of chemical action and microwaves.

Description

Ternary coupling excited tailing powder and product thereof

Technical Field

The invention belongs to the technical field of materials, and particularly relates to ternary coupling excited tailing powder and a product thereof.

Background

With the development of industry, a large amount of metal materials are applied, and accordingly a large amount of tailings of metal ore dressing is generated, and the large amount of tailings cannot be applied in an open-air stacking state for a long time, so that the environment is polluted, and potential safety hazards exist. The copper-iron tailing sand is industrial waste discharged by mining industry and related smelting industry, the existing stacking amount in China exceeds billions of tons, the increment of thousands of tons per year is increased, the condition of applying the tailing sand and the steel slag in China is far lower than the international level at present, the application amount is only 12 percent at present, the copper-iron tailing sand is mainly used as an additive of a cement plant, the application in other aspects is rarely reported, the application amount of the tailing sand in foreign countries is up to more than 80 percent, the application range is extremely wide, the copper-iron tailing sand is not only applied to the building aspect, but also applied to other aspects, and therefore, the tailing sand and the steel slag are reasonably applied to become an urban mineral resource market which is extremely wide.

At present, the energy consumption of main treatment methods for treating the tailing sand is high, for example, the method for producing the microcrystalline glass and the microcrystalline ceramic and firing the cement need to consume a large amount of energy and generate a large amount of waste gas, although the problem of recycling of part of the tailing sand is solved, secondary pollution is inevitably generated, the final purposes of completely utilizing waste and protecting the environment are not achieved, and meanwhile, the use of a large amount of tailing sand is greatly limited due to the restriction of cost and uncontrollable quality of raw materials, and the factors directly cause the condition of low use amount of the tailing sand so far.

Disclosure of Invention

The invention aims to provide the ternary coupling excited tailing powder and the products thereof, which can greatly consume the tailings, improve the added value of the comprehensive utilization of solid wastes, and have very obvious economic and social benefits.

The technical purpose of the invention is realized by the following technical scheme: the preparation method comprises the following steps:

s1, grinding the tailings containing the silicon and aluminum materials and 0.1-5 mol/L of chemical exciting agent together, and adding an aluminum correction material to mix to prepare a mixture, wherein the ratio of Si to Al of the mixture is less than or equal to 1: 5;

s2, placing the mixture and silicon carbide balls in a ball mill with a microwave generator for ball milling, wherein the ball-to-material ratio of the silicon carbide balls to the mixture is 20: 1-20: 5;

and S3, activating the mixture by turning on a microwave generator while performing ball milling, wherein the microwave heating temperature is 500-900 ℃, and obtaining the active tailing powder after activation.

The invention is further provided with: the tailings containing the silicoalumina materials are copper tailings or iron tailings.

The invention is further provided with: the aluminum correction material is a substance with the content of aluminum oxide > 50%, and the aluminum oxide comprises one or more of aluminate, aluminum oxide, aluminum hydroxide and aluminate cement.

By adopting the technical scheme: the proportion of the silicon-aluminum material in the copper-iron tailings is not suitable for preparing high-performance geopolymer materials, the main reason is that the ratio of Si to Al is too large and exceeds the optimal proportion of 1:5, and the Si to Al ratio can reach a proper range by adding an aluminum correction material, so that geopolymer materials with structures of PS, PSS and the like can be formed. The added aluminum correction material is preferably industrial waste containing aluminum oxide, such as bauxite tailings, and most preferably bauxite tailings, on one hand, the bauxite tailings have high content of aluminum oxide (50%), mainly diaspore (29%), kaolinite (33%), illite (21%), and high content of kaolin structures, on the other hand, the tailings belong to tailings with large reserves, have fine particles, are easy to raise dust, flow and settle, and have high pressure for treatment and absorption. The aluminum correction material in the present invention only serves to adjust the Si to Al ratio in the overall active tailings fines, and is essentially different from the direct preparation of geopolymer materials using bauxite tailings as described in the prior patents.

The invention is further provided with: the aluminum oxide comprises aluminate clinker or bauxite tailings.

The invention is further provided with: the chemical activator is one or more of alkali metal compound, alkaline earth metal compound, hydroxide, carbonate and sulfite.

By adopting the technical scheme: the chemical activator used in the coupling excitation stage in the present invention is a compound having high alkalinity, and may be an alkali metal compound, or an alkaline earth metal compound, and compounds capable of breaking silicon-aluminum bonds such as hydroxide, carbonate, sulfite, and the like may be used in the present invention.

The invention is further provided with: the concentration range of the chemical excitant is 0.5-1.5 mol/L.

The invention is further provided with: the ball-material ratio of the silicon carbide balls to the mixture ranges from 10:1 to 10: 1.5.

The invention is further provided with: the microwave frequency is 900MHz or 2450 MHz.

Through adopting the technical scheme, the silicon carbide balls are rapidly heated through microwaves, and materials mixed with the chemical excitant are heated at the same time, so that the chemical excitation reaction speed is accelerated, the reaction efficiency is improved, a heat source is provided for mechanical grinding, the thermal grinding is realized, and the activation degree is further improved; meanwhile, the microwave field formed inside acts on the internal molecular spacers in the tailings, so that the spacers of the silicon-aluminum material are broken under the condition of high-frequency oscillation, the crystallinity of the silicon-aluminum material is reduced, and an active surface is generated at the same time.

The wavelength of the microwave is not particularly limited, but the common frequencies are 900MHz and 2450MHz, and the frequency of 900MHz is preferred, because the penetration ability of the microwave under the frequency condition is stronger, which is more beneficial to forming an effective microwave field and carrying out the activation work of the tailings powder; the microwave generators are preferably arranged in a spatially staggered manner, preferably at intervals in the range of 300-1200 mm. And most preferably 600-900mm, so as to reduce energy consumption and ensure activation quality.

The invention is further provided with: taking the tailings powder of any one of claims 1 to 8, and uniformly mixing the tailings powder with an alkali activator and water to obtain a geopolymer material, wherein the alkali activator comprises one or more of water glass, cement, alkali metal, alkaline earth metal oxide, hydroxide, carbonate and nitrite.

By adopting the technical scheme: the alkali activator in the invention is water glass, cement, alkali metal or alkaline earth metal oxide, hydroxide, carbonate, nitrite, such as lithium oxide, calcium hydroxide, sodium hydroxide, potassium oxide, sodium carbonate, potassium nitrite, sodium nitrite, etc.; preferably water glass, cement, alkali metal carbonate, most preferably low-modulus water glass (Si02: MO 1:0.5-1.2), and for the alkali-sulfate system, besides the alkaline substances, various chemical gypsum, natural gypsum and alkali metal sulfate can be used as the sulfate component in the alkali-sulfate system, preferably alkali metal sulfate and chemical gypsum, most preferably sodium sulfate, desulfurized gypsum and phosphogypsum; the main purpose is to lead the silicon-aluminum material to form a gelled body or an inorganic polymer with certain strength by showing stronger alkalinity in water or (and) exciting the gelling activity of the silicon-aluminum material together with sulfate radicals.

The invention is further provided with: the geopolymer material as set forth in claim 9, a filler, water and an auxiliary agent, wherein the filler comprises one or more of natural sand, machine-made sand, stone chips and tailings sand, and the auxiliary agent comprises one or more of a polymer auxiliary agent, a shrinkage reducing agent and an expanding agent.

By adopting the technical scheme: under the ternary coupling action of chemical-mechanical force-microwave, the copper-iron tailings are changed into active tailing powder with considerable activity from tailing particles. The active tailing powder and the alkali activator or the alkali-sulfate activator act together to obtain a novel geopolymer material, the geopolymer material is used as a base material, and the tailing sand is used as a filler to prepare various building materials such as plates, sections, building blocks and the like of all solid waste base.

The invention has the beneficial effects that:

1. the performance of the tailing powder is improved through an activation excitation mode, so that the tailing powder becomes a structural material which can be widely used. The activity of the tailing powder is excited through chemical-mechanical-microwave ternary coupling, and geopolymer materials are prepared through alkali excitation and alkali-sulfate composite excitation methods, in the technical scheme, the dissolution rate of the silicon-aluminum materials in the tailings is improved through a chemical method, and the crystallinity of the silicon-aluminum materials in the tailings is reduced through a mechanical method, so that the silicon-aluminum materials in the tailings are changed into amorphous states with considerable activity under the chemical action and the microwave action; through the action of microwaves on the molecular interface of the silicon-aluminum material in the tailings, on one hand, the activity of the tailings is activated through the thermal action, on the other hand, the crystallinity is reduced through the high-frequency oscillation action of the microwaves, the distribution state of the amorphous silicon-aluminum material is improved, and the activity of the tailings is optimized.

2. The function of the silicon-aluminum material in the tailings powder is fully exerted through an activation excitation mode, the tailings powder is not only used as a filler of a building material, and the additional value of the tailings powder is improved.

3. Through low-temperature and high-efficiency activation excitation, the geopolymer material with the performance comparable to that of cement is prepared, the carbon emission of the cementing material is reduced, and the geopolymer material is a green low-carbon environment-friendly material in a real sense.

4. The prepared geopolymer material can also continuously use tailing sand as aggregate to prepare building materials of a whole tailing system, such as plates, sections, building blocks and other materials of the whole tailing system, and can be widely applied to engineering construction processes of buildings, traffic, municipal administration, railways, communication and the like.

5. The popularization and application of the technology of the invention really realize the purpose of changing waste into valuables, changing waste garbage into harmful waste and changing the harmful waste into beneficial waste, and is a powerful tool for solving the development and industry promotion of resource-depleted cities.

Detailed Description

The technical solutions in the examples will be clearly and completely described below. It is to be understood that the described embodiments are merely a few embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without any inventive step, are within the scope of the present invention.

Example 1

Using 100 parts of copper tailings sand, wherein (SiO)₂ 53.4％，AL₂O₃22.46%) aluminum correction material is bauxite tailings (SiO)₂ 21.5％，AL₂O₃46.3 percent) of the activated tailing powder, the corrected aluminum-silicon molar ratio is 1:2, silicon carbide balls are adopted, the ball-material ratio is 10:1, the total power of microwaves is 60kw, the ball milling time is 60min, the temperature in a ball mill is controlled to be 700-.

Example 2

120 parts of copper tailings sand of which (SiO)₂ 35.8％，AL₂O₃32.2%) of the aluminum correction material is aluminate clinker (SiO)₂ 7.2.％AL₂O₃59.3 percent of the activated tailing powder, the corrected aluminum-silicon molar ratio is 1:1, silicon carbide balls are adopted, the ball-material ratio is 9:1, the total microwave power is 60kw, the ball milling time is 60min, the temperature in the ball mill is controlled to be 700-.

Example 3

180 parts of iron tailings sand are used, of which (SiO)₂ 58.4％，AL₂O₃18.46%) aluminum correction material is bauxite tailings (SiO)₂ 21.5％，AL₂O₃46.3 percent) of the activated tailing powder, the corrected aluminum-silicon molar ratio is 1:2.5, silicon carbide balls are adopted, the ball-material ratio is 11:1, the total power of microwaves is 60kw, the ball milling time is 60min, the temperature in a ball mill is controlled to be 60O-700 ℃, the activated tailing powder is cooled to obtain a finished product through a waste heat recovery device, and 100 parts of the activated tailing powder, 15 parts of potassium water glass with the modulus of 1.2 and 10 parts of phosphogypsum are selected to be mixed to prepare geopolymer neat paste.

The method for preparing the geopolymer neat paste in the embodiment 1-3 is adopted, the geopolymer neat paste is cured under different conditions to obtain the test samples, the length, the width and the height of the samples are respectively 160mm and 40mm/40mm, the curing conditions and the compressive strength of the test samples are shown in the following table 1, and the compressive strength test refers to GB/T17671-.

TABLE 1

Application example 1

100 parts of the activated tailing geopolymer material, 200 parts of iron tailing sand (80-200 meshes), 5 parts of polymer auxiliary agent, 2 parts of shrinkage reducing agent, 0.8 part of expanding agent and 32 parts of water in example 1 are used, the dry powder material is mixed firstly, then the mixture is mixed with the water and stirred into paste, the paste is poured into a mold for molding, and the paste is cured for 28 days under standard conditions.

Application example 2

100 parts of the activated tailing geopolymer material, 400 parts of iron tailing sand (80-200 meshes), 5 parts of polymer auxiliary agent, 3 parts of shrinkage reducing agent, 1.2 parts of expanding agent and 35 parts of water in example 2 are used, the dry powder material is mixed firstly, then the mixture is mixed with the water and stirred into paste, the paste is poured into a mold for molding, and the paste is maintained for 28 days under standard conditions.

Application example 3

100 parts of the activated tailing geopolymer material, 150 parts of iron tailing sand (140-200 meshes), 5 parts of polymer additive, 15 parts of processing additive and 24 parts of water are used, the dry powder material is mixed and stirred with the water into paste, the paste is extruded and molded from a vacuum extrusion molding machine, and then the paste is cured for 8 hours under the wet and hot condition of 80 ℃, and then the geopolymer extruded plate is obtained after natural drying.

Application example 4

100 parts of the activated tailing geopolymer material in example 3, 550 parts of iron tailing sand (80-200 meshes), 8 parts of polymer auxiliary agent, 3.5 parts of shrinkage reducing agent, 1.5 parts of expanding agent and 40 parts of water are used, dry powder materials are mixed firstly, then the mixture is mixed with water and stirred into paste, the paste is poured into a mold for molding, then the paste is cured for 12 hours under the damp and hot condition of 60 ℃, and geopolymer building blocks are obtained through natural drying.

Application example 5

100 parts of the activated tailing geopolymer material of the example 2, 300 parts of iron tailing sand (80-200 days), 5 parts of polymer auxiliary agent, 3.5 parts of water reducing shrinkage reducing agent, 3 parts of expanding agent and 22 parts of water are used, dry powder materials are mixed firstly, then the mixture is mixed with the water and stirred into paste fluid, the paste fluid is poured into a mold for molding, and the surface-shaped cultural brick is obtained after curing for 28 days under standard conditions.

Preparing geopolymer product samples according to the methods of the application examples 1-5, wherein the length, the width and the height of the samples are respectively 160mm and 40mm/40mm, and detecting the compressive strength, the anti-permeability grade and the water absorption of the products, wherein the compressive strength and the compressive strength are tested by reference to GB/T17671-2020; the impermeability grade test is referred to GB-50164-2011, and the detection results are shown in the following table 2.

TABLE 2

From the data of the test results in table 1, it can be found that the strength of the clean slurry prepared by using the activated tailing powder after curing for 28d at room temperature reaches the standard of 4.25 cement, which indicates that the geopolymer material with good compression resistance can be prepared by exciting the activity of the tailing powder through chemical-mechanical-microwave ternary coupling and by adopting the methods of alkali excitation and alkali-sulfate composite excitation.

From the data of the test results in table 2, it can be found that the section prepared by mixing the activated tailing powder, the iron tailing sand and the auxiliary agent in application examples 1-2 has high compressive strength, flexural strength and impermeability grade, and the geopolymer material prepared by using the activated tailing powder, the iron tailing sand and other auxiliary agents in application examples 3-5 can obtain building materials with good performance by preparing plates, building blocks and culture bricks.

Claims

1. The ternary coupling excited tailing powder is characterized in that: the preparation method comprises the following steps:

2. The ternary-coupled excited tailings powder of claim 1, wherein: the tailings containing the silicoalumina materials are copper tailings or iron tailings.

3. The ternary-coupled excited tailings powder of claim 1, wherein: the aluminum correction material is a substance with the content of aluminum oxide > 50%, and the aluminum oxide comprises one or more of aluminate, aluminum oxide, aluminum hydroxide and aluminate cement.

4. The ternary-coupled excited tailings powder of claim 3, wherein: the aluminum oxide comprises aluminate clinker or bauxite tailings.

5. The ternary-coupled excited tailings powder of claim 1, wherein: the chemical activator is one or more of alkali metal compound, alkaline earth metal compound, hydroxide, carbonate and sulfite.

6. The ternary-coupled excited tailings powder of claim 5, wherein: the concentration range of the chemical excitant is 0.5-1.5 mol/L.

7. The ternary-coupled excited tailings powder of claim 1, wherein: the ball-material ratio of the silicon carbide balls to the mixture ranges from 10:1 to 10: 1.5.

8. The ternary-coupled excited tailings powder of claim 1, wherein: the microwave frequency is 900MHz or 2450 MHz.

9. A geopolymer material characterized by: taking the tailings powder of any one of claims 1 to 8, and uniformly mixing the tailings powder with an alkali activator and water to obtain a geopolymer material, wherein the alkali activator comprises one or more of water glass, cement, alkali metal, alkaline earth metal oxide, hydroxide, carbonate and nitrite.

10. A building material characterized by: the geopolymer material as set forth in claim 9, a filler, water and an auxiliary agent, wherein the filler comprises one or more of natural sand, machine-made sand, stone chips and tailings sand, and the auxiliary agent comprises one or more of a polymer auxiliary agent, a shrinkage reducing agent and an expanding agent.