Environment-friendly concrete admixture capable of recycling industrial waste residues and preparation method of environment-friendly concrete admixture

Abstract

The invention relates to an environment-friendly concrete admixture capable of recycling industrial waste residues and a preparation method of the environment-friendly concrete admixture. According to the method, the household garbage incineration slag is modified firstly, so that the strength of the household garbage incineration slag can be remarkably improved, the porosity and the like of the household garbage incineration slag can be remarkably reduced, and leaching and the like of heavy metal ions of the household garbage incineration slag can be reduced; the environment-friendly concrete admixture which is excellent in performance and capable of recycling the industrial waste residues can be prepared. According to the environment-friendly concrete admixture, the synergistic and complementary effects of different types of smelting slag and raw materials are fully exerted, and the shrinkage resistance and the like of the composite admixture from the early stage to the later stage are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of concrete, and in particular to an environmentally friendly concrete admixture that recycles industrial waste residues and a preparation method thereof. Background Art

[0002] In the concrete industry, in addition to cement, admixtures have become an indispensable component of concrete. Commonly used admixtures are mainly based on high-quality slag powder and first-grade fly ash. However, due to the rapid development of infrastructure, the amount of concrete used is increasing, and the crack resistance requirements are high. High-quality fly ash, mineral powder and other admixtures can no longer meet the current demand. In order to reduce costs, expand the source of raw materials for admixtures and protect the environment, it is very urgent to recycle waste materials such as industrial waste and slag.

[0003] With the rapid development of urbanization in my country, the output of urban domestic waste is increasing day by day. How to deal with these long-accumulated domestic waste has become a major problem for the healthy development of cities. Incineration and comprehensive utilization of domestic waste is an effective means to achieve waste reduction, harmlessness and resource utilization, with good social and environmental benefits. However, with the increase in the amount of domestic waste incineration, a large amount of solid waste incineration slag will be generated. Previous studies have found that the engineering properties of domestic waste incineration ash are similar to those of natural aggregates. It is mainly composed of slag, ferrous and non-ferrous metals, ceramic fragments, glass and some other non-combustible inorganic substances and incompletely burned organic matter. The main components are Ca, Si, Na, K, Fe, Al and some heavy metals.

[0004] Although there are reports that domestic waste incineration slag can be used as building materials, the unmodified domestic waste incineration slag contains a large number of pore structures and about 5% of unburned organic matter, which seriously affects the engineering properties of domestic waste incineration slag as a building material. In addition, domestic waste incineration slag contains high concentrations of heavy metals, and the dissolution of heavy metals is also one of the reasons that limit the efficient use of domestic waste incineration slag. Therefore, how to convert domestic waste incineration slag into a recyclable industrial waste slag environmentally friendly concrete admixture has become an important research topic at present. Summary of the invention

[0005] The purpose of the present invention is to provide an environmentally friendly concrete admixture that recycles industrial waste slag and a preparation method thereof in view of the deficiencies in the prior art, so as to realize the transformation of waste into treasure, resource recycling, reduce production costs, expand the source of raw materials for admixtures, and protect the environment.

[0006] In order to achieve the above purpose, this application adopts the following technical solutions:

[0007] The environmentally friendly concrete admixture that recycles industrial waste slag is characterized in that the raw materials of the environmentally friendly concrete admixture that recycles industrial waste slag include the following raw materials: lithium slag, phosphorus slag, titanium slag and modified domestic waste incineration furnace slag;

[0008] Furthermore, the lithium slag includes but is not limited to the lithium slag produced in the process of preparing lithium carbonate by sulfuric acid method;

[0009] Furthermore, the titanium slag includes waste slag obtained by cooling the slag discharged during the smelting of vanadium-titanium magnetite in a blast furnace;

[0010] Furthermore, the phosphorus slag includes solid waste residue produced by preparing yellow phosphorus by electric furnace method;

[0011] Furthermore, the environmentally friendly concrete admixture that recycles industrial waste residues includes, by weight, 30-70 parts of modified domestic waste incineration slag, 10-20 parts of lithium slag, 15-30 parts of phosphorus slag, and 10-20 parts of titanium slag;

[0012] Furthermore, the environmentally friendly concrete admixture made by recycling industrial waste residues comprises 40-60 parts of modified domestic waste incineration slag, 10-20 parts of lithium slag, 15-30 parts of phosphorus slag, and 12-18 parts of titanium slag.

[0013] Furthermore, the environmentally friendly concrete admixture that recycles industrial waste residues includes 50 kg of modified domestic waste incineration slag, 10 kg of lithium slag, 25 kg of phosphorus slag, and 15 kg of titanium slag;

[0014] Furthermore, the environmentally friendly concrete admixture that recycles industrial waste residues also includes a composite abrasive; the raw materials of the composite abrasive include triethanolamine, sodium tripolyphosphate, polyvinyl pyrrolidone and water;

[0015] Furthermore, the weight ratio of triethanolamine, sodium tripolyphosphate, polyvinyl pyrrolidone and water is 12-16:6-10:3-7:60-70, preferably 14:8:5:65;

[0016] Furthermore, the environmentally friendly concrete admixture recycled from industrial waste residues comprises, by weight, 30-70 parts of modified domestic waste incineration slag, 10-20 parts of lithium slag, 15-30 parts of phosphorus slag, 10-20 parts of titanium slag and 0.8-1.2 parts of composite abrasive;

[0017] Furthermore, the method for preparing the modified domestic waste incineration slag comprises:

[0018] Step S1: drying the domestic waste incineration slag, then feeding the dried domestic waste incineration slag into a grinder for grinding, and then feeding the ground domestic waste incineration slag into a rotary drum screen for screening, and screening the screened product;

[0019] Step S2: taking the screened material, sodium sulfide, light-burned magnesium oxide, and magnesium chloride and sending them into a high-temperature calcining furnace for calcining, and after the screened material is completely melted, dispersing them into water for rapid cooling, and then drying the product obtained after rapid cooling again to obtain modified domestic waste incineration slag;

[0020] Furthermore, in step S1, the specific conditions for drying are: drying at 105-115° C. for 6-10 hours;

[0021] Furthermore, the pore size of the sieve is 0.5-1.5 mm;

[0022] Further, in step S2, the screened material is 80-120 parts, the sodium sulfide is 1-3 parts, the light-burned magnesium oxide is 3-7 parts, and the magnesium chloride is 3-7 parts by weight;

[0023] Further, the calcination temperature is 750-850°C;

[0024] Furthermore, the specific conditions for drying are: drying at 105-115° C. for 6-10 hours.

[0025] Furthermore, in step S2, in parts by weight, the screened material is 90-110 parts, the sodium sulfide is 1-3 parts, the light-burned magnesium oxide is 4-6 parts, and the magnesium chloride is 4-6 parts.

[0026] Furthermore, the method comprises the following steps: placing lithium slag, phosphorus slag, titanium ore slag and modified domestic waste incineration slag in a ball mill, adding a composite grinding agent and performing ball milling, and the specific surface area of ​​the product after ball milling is 550-600m 2 / kg, an environmentally friendly concrete admixture is obtained.

[0027] Beneficial effects:

[0028] The present invention first modifies the slag from the incineration of domestic waste, which can not only significantly improve the strength of the slag from the incineration of domestic waste, but also reduce the leaching of heavy metal ions from the slag from the incineration of domestic waste, etc., and then grinds the slag together with lithium slag, phosphorus slag, titanium slag, etc., to prepare an environmentally friendly concrete admixture that recycles industrial waste slag with excellent performance. The environmentally friendly concrete admixture gives full play to the synergistic and complementary effects of different types of smelting slag and raw materials, and realizes the anti-shrinkage ability of the composite admixture from early to late stages. DETAILED DESCRIPTION

[0029] The present invention is further described below in conjunction with the following embodiments. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application. In addition, it should be understood that the specific embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0030] Example 1

[0031] This embodiment provides an environmentally friendly concrete admixture that recycles industrial waste slag and a preparation method thereof, and the specific steps are as follows:

[0032] Step S1: drying the domestic waste incineration slag at 110° C. for 8 h, then feeding the dried domestic waste incineration slag into a grinder for grinding, and then feeding the ground domestic waste incineration slag into a rotary sieve for screening, wherein the aperture of the sieve is 1 mm, and screening to obtain undersize product screening material A;

[0033] Step S2: 100 kg of the screened material A, 2 kg of sodium sulfide, 5 kg of light-burned magnesium oxide, and 5 kg of magnesium chloride are sent into a high-temperature calcining furnace for calcination at a temperature of 800° C. After the screened material is completely melted, it is immediately dispersed and put into ice water for rapid cooling. The product obtained after rapid cooling is then dried again at 110° C. for 8 hours to obtain modified domestic waste incineration slag;

[0034] Step S3: triethanolamine, sodium tripolyphosphate, polyvinyl pyrrolidone (K30, produced by Tianjin Hainachuan Technology Development Co., Ltd.) and water are stirred and dissolved at room temperature in a weight ratio of 14:8:5:65 to obtain a composite grinding aid; then 50 kg of modified domestic waste incineration slag, 10 kg of lithium slag, 25 kg of phosphorus slag, 15 kg of titanium slag and 1 kg of the composite grinding aid are sent into a ball mill for ball milling, and the specific surface area is controlled at 550-600 m 2 / kg, you can get an environmentally friendly concrete admixture.

[0035] Example 2

[0036] This embodiment provides an environmentally friendly concrete admixture that recycles industrial waste residues and a preparation method thereof, and the specific steps are as follows:

[0037] Step S1: drying the domestic waste incineration slag at 110±5°C for 8h, then feeding the dried domestic waste incineration slag into a grinder for grinding, and then feeding the ground domestic waste incineration slag into a rotary screen for screening, wherein the aperture of the screen is 1mm, and screening to obtain undersize product screening material A;

[0038] Step S2: 100 kg of the screened material A, 2 kg of sodium sulfide, 5 kg of light-burned magnesium oxide, and 5 kg of magnesium chloride are sent into a high-temperature calcining furnace for calcination at a temperature of 800° C. After the screened material is completely melted, it is immediately dispersed and put into ice water for rapid cooling. The product obtained after rapid cooling is then dried again at 110±5° C. for 8 hours to obtain modified domestic waste incineration slag;

[0039] Step S3: triethanolamine, sodium tripolyphosphate, polyvinyl pyrrolidone (K30, produced by Tianjin Hainachuan Technology Development Co., Ltd.) and water are stirred and dissolved at room temperature in a weight ratio of 14:8:5:65 to obtain a composite grinding aid; then 40 kg of modified domestic waste incineration slag, 20 kg of lithium slag, 25 kg of phosphorus slag, 15 kg of titanium slag and 1 kg of the composite grinding aid are sent into a ball mill for ball milling, and the specific surface area is controlled at 550-600 m 2 / kg, you can get an environmentally friendly concrete admixture.

[0040] Example 3

[0041] This embodiment provides an environmentally friendly concrete admixture that recycles industrial waste residues and a preparation method thereof, and the specific steps are as follows:

[0042] Step S1: drying the domestic waste incineration slag at 110±5°C for 8h, then feeding the dried domestic waste incineration slag into a grinder for grinding, and then feeding the ground domestic waste incineration slag into a rotary screen for screening, wherein the aperture of the screen is 1mm, and screening to obtain undersize product screening material A;

[0043] Step S2: 100 kg of the screened material A, 2 kg of sodium sulfide, 5 kg of light-burned magnesium oxide, and 5 kg of magnesium chloride are sent into a high-temperature calcining furnace for calcination at a temperature of 800° C. After the screened material is completely melted, it is immediately dispersed and put into ice water for rapid cooling. The product obtained after rapid cooling is then dried again at 110±5° C. for 8 hours to obtain modified domestic waste incineration slag;

[0044] Step S3: triethanolamine, sodium tripolyphosphate, polyvinyl pyrrolidone (K30, produced by Tianjin Hainachuan Technology Development Co., Ltd.) and water are stirred and dissolved at room temperature in a weight ratio of 14:8:5:65 to obtain a composite grinding aid; then 60 kg of modified domestic waste incineration slag, 10 kg of lithium slag, 15 kg of phosphorus slag, 15 kg of titanium slag and 1 kg of the composite grinding aid are sent into a ball mill for ball milling, and the specific surface area is controlled at 550-600 m 2 / kg, you can get an environmentally friendly concrete admixture.

[0045] Comparative Example 1:

[0046] Compared with Example 1, the only difference is that "5 kg of light-burned magnesia" is not added in step S2.

[0047] Comparative Example 2:

[0048] Compared with Example 1, the only difference is that "5 kg of magnesium chloride" is not added in step S2.

[0049] Comparative Example 3:

[0050] Triethanolamine, sodium tripolyphosphate, polyvinyl pyrrolidone (K30, produced by Tianjin Hainachuan Technology Development Co., Ltd.) and water were stirred and dissolved at room temperature in a weight ratio of 14:8:5:65 to obtain a composite grinding aid; 10 kg of lithium slag, 15 kg of phosphorus slag, 15 kg of titanium slag and 1 kg of the composite grinding aid were sent into a ball mill for ball milling, and the specific surface area was controlled at 550-600 m 2 / kg, to obtain environmentally friendly concrete admixture.

[0051] Application Examples

[0052] According to Appendix A of Composite Admixtures for Concrete JG / T 486-2015, the 7d activity index, 28d activity index and fluidity ratio of the composite mineral admixture were tested at a mass ratio of cement to the environmentally friendly concrete admixtures in Examples 1-3 and Comparative Example 1 of 8:2. The results are shown in Table 1.

[0053] According to GB / T 17671-2021, the molding was carried out according to the mass ratio of cement to the environmentally friendly concrete admixtures in Examples 1-3 and Comparative Example 1 of 7:3. The mortar specimens were filled with a 40mm×40mm×160mm triple steel mold. The two end plates of the mold each had 3 6mm blind holes. Before molding, a round-headed copper rod probe with a length of 2.5cm and a diameter of 6mm was placed. After molding, the surface was covered with a layer of plastic wrap and placed in a standard curing room at a curing temperature of (20±3)℃ and a relative humidity of more than 90%. The mold was removed after curing for 1d; the initial value of the specimen length was determined with a screw micrometer (unit: mm accurate to 0·001mm); the specimen was moved into a constant temperature and humidity chamber (curing temperature (20±2)℃ and relative humidity 60%±5%) to test the length of the specimen at the beginning of curing and 28d, respectively, and its shrinkage rate was tested. The results are shown in Table 1.

[0054] Table 1 Test results

[0055] 7d activity index / % 28d activity index / % Fluidity ratio 28d shrinkage Example 1 88 97 105 97 Example 2 82 94 103 94 Example 3 79 93 101 92 Comparative Example 1 73 88 92 115 Comparative Example 2 70 84 90 120 Comparative Example 3 58 69 82 137

[0056] The mineral composite mineral admixture prepared according to the present invention can meet the requirements of 7d activity index ≥79%, 28d activity index ≥93%, and fluidity ratio ≥101%, which are all better than those of comparative examples 1-3. At the same time, its 28d shrinkage rate is also significantly reduced relative to that of the comparative example 1 (without mineral admixture), which can effectively reduce the shrinkage of the matrix material and is beneficial to improving the ability of cement-based materials to resist shrinkage cracking.

[0057] The above is a detailed introduction to the environmentally friendly concrete admixture for recycling industrial waste slag and its preparation method provided in the embodiments of the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for technical personnel in this field, according to the ideas of the present application, there will be changes in the specific implementation methods and application scopes. Any equivalent modifications or changes made by ordinary technicians in this field based on the contents disclosed by the present invention should be included in the protection scope recorded in the claims.

Claims

1. An environmentally friendly concrete admixture that recycles industrial waste residues, characterized in that: The raw materials include: lithium slag, phosphorus slag, titanium slag and modified domestic waste incineration slag.

2. The environmentally friendly concrete admixture made by recycling industrial waste residue according to claim 1, characterized in that: By weight, the raw materials of the environmentally friendly concrete admixture that recycles industrial waste slag include 30-70 parts of modified domestic waste incineration slag, 10-20 parts of lithium slag, 15-30 parts of phosphorus slag, and 10-20 parts of titanium slag.

3. The environmentally friendly concrete admixture made by recycling industrial waste residue according to any one of claims 1 to 2, characterized in that: Also included are composite abrasives; The raw materials of the composite abrasive include triethanolamine, sodium tripolyphosphate, polyvinyl pyrrolidone and water.

4. The environmentally friendly concrete admixture made by recycling industrial waste residue according to claim 3, characterized in that: The weight ratio of triethanolamine, sodium tripolyphosphate, polyvinyl pyrrolidone and water is 12-16:6-10:3-7:60-70, preferably 14:8:5:65; And / or, in parts by weight, the raw materials of the environmentally friendly concrete admixture that recycles industrial waste slag include 30-70 parts of modified domestic waste incineration slag, 10-20 parts of lithium slag, 15-30 parts of phosphorus slag, 10-20 parts of titanium slag and 0.8-1.2 parts of composite abrasive.

5. The environmentally friendly concrete admixture made by recycling industrial waste residue according to any one of claims 1 to 2, characterized in that: The method for preparing the modified domestic waste incineration slag comprises: Step S1: drying the domestic waste incineration slag, then feeding the dried domestic waste incineration slag into a grinder for grinding, and then feeding the ground domestic waste incineration slag into a rotary drum screen for screening, and screening the screened product; Step S2: taking the screened material, sodium sulfide, light-burned magnesium oxide and magnesium chloride and sending them into a high-temperature calcining furnace for calcining; after the screened material is completely melted, dispersing them into water for rapid cooling; then drying the product obtained after rapid cooling again to obtain modified domestic waste incineration slag.

6. The environmentally friendly concrete admixture made by recycling industrial waste residue according to claim 5, characterized in that: In step S1, the specific conditions for drying are: drying at 105-115° C. for 6-10 hours; And / or, the pore size of the sieve is 0.5-1.5 mm.

7. The environmentally friendly concrete admixture made by recycling industrial waste residue according to claim 5, characterized in that: In the step S2, the screened material is 80-120 parts, the sodium sulfide is 1-3 parts, the light-burned magnesium oxide is 3-7 parts, and the magnesium chloride is 3-7 parts by weight; And / or, the calcination temperature is 750-850°C; And / or, the specific conditions of drying are: drying at 105-115° C. for 6-10 hours.

8. The environmentally friendly concrete admixture made by recycling industrial waste residue according to claim 7, characterized in that: In the step S2, by weight, the screened material is 90-110 parts, the sodium sulfide is 1-3 parts, the light-burned magnesium oxide is 4-6 parts, and the magnesium chloride is 4-6 parts.

9. A method for preparing an environmentally friendly concrete admixture by recycling industrial waste residue according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: placing lithium slag, phosphorus slag, titanium ore slag and modified domestic waste incineration slag in a ball mill, adding a composite grinding agent and performing ball milling, and the specific surface area of ​​the product after ball milling is 550-600m 2 / kg, an environmentally friendly concrete admixture is obtained.

10. The preparation method according to claim 9, characterized in that: The weight ratio of the triethanolamine, sodium tripolyphosphate, polyvinyl pyrrolidone and water is 14:8:5:65.