Method for preparing aerated concrete block by mineralizing waste incineration flue gas and aerated concrete block

Abstract

The invention relates to the technical field of carbon sequestration and emission reduction, and discloses a method for preparing an aerated concrete block by mineralizing waste incineration flue gas and the aerated concrete block. The method comprises the following steps: mixing 30-40% of waste incineration slag, 10-15% of fly ash, 20-25% of steel slag, 5-10% of lime and 20-30% of cement according to the total mass fraction of 100% to prepare a mixture, adding water and a foaming agent into the mixture, and carrying out stirring, pouring and demolding treatment to prepare the aerated concrete block. And carrying out mineralization treatment on the aerated concrete block green body by utilizing waste incineration flue gas, so as to prepare the aerated concrete block. According to the method, the high-quality aerated concrete block sample can be obtained, co-processing and resource utilization of the waste incineration slag and the fly ash can be achieved, and the carbon emission reduction level of a waste incineration power plant can be improved. The aerated concrete block product can be applied to various building fields.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon sequestration and emission reduction, and in particular to a method for preparing aerated concrete blocks by mineralizing waste incineration flue gas and the aerated concrete blocks prepared by the method. Background Art

[0002] Currently, incineration technology has become the dominant method for treating municipal solid waste. With the large amounts of incineration slag and fly ash generated, effective treatment of these wastes has become a research hotspot. This invention utilizes flue gas from waste incineration power plants to perform a synergistic mineralization treatment on the waste incineration slag and fly ash, resulting in aerated concrete blocks with a wide range of applications. It also reduces carbon emissions from waste incineration flue gas, offering significant environmental and economic benefits. Summary of the Invention

[0003] One of the purposes of the present invention is to provide a method for preparing aerated concrete blocks by mineralizing waste incineration flue gas, which can realize the coordinated disposal and resource utilization of waste incineration slag and fly ash, and achieve the effect of reducing carbon emissions from waste incineration flue gas.

[0004] A second object of the present invention is to provide an aerated concrete block whose bulk density and compressive strength both meet the requirements of the superior product (B) in standard number GB11968-2006.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] On the one hand, a method for preparing aerated concrete blocks by mineralizing waste incineration flue gas is provided, characterized in that, based on a total mass fraction of 100%, 30%-40% of waste incineration slag, 10%-15% of fly ash, 20%-25% of steel slag, 5%-10% of lime, and 20%-30% of cement are mixed to prepare a mixture; water and a foaming agent are added to the mixture, and an aerated concrete block body is prepared by stirring, pouring, and demolding; and the aerated concrete block body is mineralized using a gas containing CO2 to prepare an aerated concrete block.

[0007] As a preferred embodiment of the method for preparing aerated concrete blocks by mineralizing waste incineration flue gas, the mass ratio of the water to the fly ash is 0.6-0.7.

[0008] As a preferred embodiment of the method for preparing aerated concrete blocks by mineralizing waste incineration flue gas, the foaming agent is selected from aluminum powder.

[0009] As a preferred solution of the method for preparing aerated concrete blocks by mineralizing waste incineration flue gas, the amount of the foaming agent added is 1‰-2‰ based on the total mass of the mixture.

[0010] As a preferred solution for the method of preparing aerated concrete blocks by mineralizing waste incineration flue gas, the mineralization treatment refers to placing the concrete block blanks after casting and demoulding in a high-pressure reactor and introducing waste incineration flue gas to carry out mineralization reaction.

[0011] As a preferred embodiment of the method for preparing aerated concrete blocks by mineralizing waste incineration flue gas, the temperature of the mineralization reaction is 55° C.-65° C., the pressure is 1.5 MPa-1.7 MPa, and the time is 10 h-15 h.

[0012] As a preferred embodiment of the method for preparing aerated concrete blocks by mineralizing waste incineration flue gas, the mass fraction of CO2 in the waste incineration flue gas is 13%.

[0013] As a preferred solution of the method for preparing aerated concrete blocks by mineralizing waste incineration flue gas, the casting and demoulding refer to casting and molding using a mold, and then standing for 20 hours to 36 hours before performing the demoulding treatment.

[0014] As a preferred embodiment of the method for preparing aerated concrete blocks by mineralizing waste incineration flue gas, the particle size of the waste incineration slag is less than 1 mm.

[0015] On the other hand, an aerated concrete block is provided, which is produced by the method for producing aerated concrete blocks by mineralizing waste incineration flue gas, and the aerated concrete block meets the requirements of superior product (B) in standard number GB11968-2006.

[0016] Beneficial effects of the present invention:

[0017] (1) The present invention uses waste incineration slag as the main raw material, mixes in a small amount of fly ash, and then adds a certain amount of steel slag, lime, cement, and a trace amount of aluminum powder as a foaming agent. Through mixing, casting, molding, demoulding, and utilizing the mineralization of waste incineration flue gas, high-quality aerated concrete block samples can be obtained. The present invention can achieve the coordinated disposal and resource utilization of waste incineration slag and fly ash; at the same time, the mineralization reaction process can capture, solidify, and utilize CO2 in the flue gas, which is beneficial to improving the carbon emission reduction level of waste incineration power plants and has very significant environmental benefits.

[0018] (2) The aerated concrete block product of the present invention meets the requirements of the superior product (B) in the standard number GB11968-2006, can be applied to various construction fields, and has very obvious economic benefits. DETAILED DESCRIPTION

[0019] The technical solution of the present invention is further illustrated below through specific implementation methods.

[0020] Unless otherwise specified, the various raw materials of the present invention can be purchased commercially or prepared according to conventional methods in the art.

[0021] Example 1

[0022] The preparation method of the aerated concrete block sample of this embodiment is as follows:

[0023] (1) Using garbage incinerator slag (40%) (particle size <1mm) and fly ash (15%) as the main raw materials, and then adding a certain amount of high calcium steel slag (20%), lime (5%), and cement (20%), the raw materials are evenly mixed and then a certain amount of water (water / ash ratio = 0.6) is added. After stirring thoroughly, a small amount of foaming agent aluminum powder (1.5‰) is added, and stirring is continued thoroughly. Then, the mold is used for casting and molding, and the mold is demoulded after standing for 24 hours to obtain an aerated concrete block body;

[0024] (2) Place the demolded aerated concrete block in a high-pressure reactor for mineralization. Mineralization reaction conditions: 60°C; mineralization pressure: 1.6 MPa; mineralization time: 12 hours; mineralization gas: waste incineration flue gas (CO2 content: approximately 13%). After the mineralization reaction is completed, remove the aerated concrete block sample and cool it.

[0025] Example 2

[0026] The preparation method of the aerated concrete block sample of this embodiment is as follows:

[0027] (1) Using garbage incinerator slag (30%) (particle size <1mm) and fly ash (10%) as the main raw materials, and then adding a certain amount of high calcium steel slag (25%), lime (5%), and cement (30%), the raw materials are evenly mixed and then a certain amount of water (water / ash ratio = 0.7) is added. After stirring thoroughly, a small amount of foaming agent aluminum powder (2‰) is added, and stirring is continued thoroughly. Then, the mold is used for casting and molding, and the mold is demoulded after standing for 20 hours to obtain an aerated concrete block body;

[0028] (2) Place the demolded aerated concrete block in a high-pressure reactor for mineralization. Mineralization reaction conditions: 60°C; mineralization pressure: 1.6 MPa; mineralization time: 12 hours; mineralization gas: waste incineration flue gas (CO2 content: approximately 13%). After the mineralization reaction is completed, remove the aerated concrete block sample and cool it.

[0029] Example 3

[0030] The preparation method of the aerated concrete block sample of this embodiment is as follows:

[0031] (1) Using garbage incinerator slag (35%) (particle size <1mm) and fly ash (10%) as the main raw materials, and then adding a certain amount of high calcium steel slag (25%), lime (5%), and cement (25%), the raw materials are evenly mixed and then a certain amount of water (water / ash ratio = 0.65) is added. After stirring thoroughly, a small amount of foaming agent aluminum powder (2‰) is added, and stirring is continued to be thorough. Then, the mold is used for casting and molding, and the mold is demoulded after standing for 24 hours to obtain an aerated concrete block body;

[0032] (2) Place the demolded aerated concrete block in a high-pressure reactor for mineralization. Mineralization reaction conditions: 60°C; mineralization pressure: 1.6 MPa; mineralization time: 12 hours; mineralization gas: waste incineration flue gas (CO2 content: approximately 13%). After the mineralization reaction is completed, remove the aerated concrete block sample and cool it.

[0033] Example 4

[0034] The preparation method of the aerated concrete block sample of this embodiment is as follows:

[0035] (1) Using garbage incinerator slag (30%) (particle size <1mm) and fly ash (15%) as the main raw materials, and then adding a certain amount of high calcium steel slag (20%), lime (10%), and cement (25%), the raw materials are evenly mixed and then a certain amount of water (water / ash ratio = 0.65) is added. After stirring thoroughly, a small amount of foaming agent aluminum powder (1‰) is added, and stirring is continued to be thorough. Then, the mold is used for casting and molding, and the mold is demoulded after standing for 20 hours to obtain an aerated concrete block body;

[0036] (2) Place the demolded aerated concrete block in a high-pressure reactor for mineralization. Mineralization reaction conditions: 60°C; mineralization pressure: 1.6 MPa; mineralization time: 12 hours; mineralization gas: waste incineration flue gas (CO2 content: approximately 13%). After the mineralization reaction is completed, remove the aerated concrete block sample and cool it.

[0037] Example 5

[0038] The preparation method of the aerated concrete block sample of this embodiment is as follows:

[0039] (1) Using garbage incinerator slag (35%) (particle size <1mm) and fly ash (15%) as the main raw materials, and then adding a certain amount of high calcium steel slag (20%), lime (10%), and cement (20%), the raw materials are evenly mixed and then a certain amount of water (water / ash ratio = 0.60) is added. After stirring thoroughly, a small amount of foaming agent aluminum powder (1‰) is added, and stirring is continued to be thorough. Then, the mold is used for casting and molding, and the mold is demoulded after standing for 18 hours to obtain an aerated concrete block body;

[0040] (2) Place the demolded aerated concrete block in a high-pressure reactor for mineralization. Mineralization reaction conditions: 60°C; mineralization pressure: 1.6 MPa; mineralization time: 12 hours; mineralization gas: waste incineration flue gas (CO2 content: approximately 13%). After the mineralization reaction is completed, remove the aerated concrete block sample and cool it.

[0041] Example 6

[0042] The preparation method of the aerated concrete block sample of this embodiment is as follows:

[0043] (1) Using garbage incinerator slag (35%) (particle size <1mm) and fly ash (10%) as the main raw materials, and then adding a certain amount of high calcium steel slag (20%), lime (5%), and cement (30%), the raw materials are evenly mixed and then a certain amount of water (water / ash ratio = 0.60) is added. After stirring thoroughly, a small amount of foaming agent aluminum powder (1.5‰) is added, and stirring is continued. Then, the mold is used for casting and molding, and the mold is demoulded after standing for 24 hours to obtain an aerated concrete block body;

[0044] (2) Place the demolded aerated concrete block in a high-pressure reactor for mineralization. Mineralization reaction conditions: 60°C; mineralization pressure: 1.6 MPa; mineralization time: 12 hours; mineralization gas: waste incineration flue gas (CO2 content: approximately 13%). After the mineralization reaction is completed, remove the aerated concrete block sample and cool it.

[0045] Comparative Example 1

[0046] The preparation method of the aerated concrete block sample of this comparative example is as follows:

[0047] (1) Using garbage incinerator slag (50%) (particle size <1mm) and fly ash (10%) as the main raw materials, and then adding a certain amount of high calcium steel slag (15%), lime (5%), and cement (20%), the raw materials are evenly mixed and then a certain amount of water (water / ash ratio = 0.65) is added. After stirring thoroughly, a small amount of foaming agent aluminum powder (1.5‰) is added, and stirring is continued to be thorough. Then, the mold is used for casting and molding, and the mold is demoulded after standing for 24 hours to obtain an aerated concrete block body;

[0048] (2) Place the demolded aerated concrete block in a high-pressure reactor for mineralization. Mineralization reaction conditions: 60°C; mineralization pressure: 1.6 MPa; mineralization time: 12 hours; mineralization gas: waste incineration flue gas (CO2 content: approximately 13%). After the mineralization reaction is completed, remove the aerated concrete block sample and cool it.

[0049] Comparative Example 2

[0050] The preparation method of the aerated concrete block sample of this comparative example is as follows:

[0051] (1) Using garbage incinerator slag (35%) (particle size <1mm) and fly ash (20%) as the main raw materials, and then adding a certain amount of high calcium steel slag (20%), lime (5%), and cement (20%), the raw materials are evenly mixed and then a certain amount of water (water / ash ratio = 0.65) is added. After stirring thoroughly, a small amount of foaming agent aluminum powder (1.5‰) is added, and stirring is continued thoroughly. Then, the mold is used for casting and molding, and the mold is demoulded after standing for 24 hours to obtain an aerated concrete block body;

[0052] (2) Place the demolded aerated concrete block in a high-pressure reactor for mineralization. Mineralization reaction conditions: 60°C; mineralization pressure: 1.6 MPa; mineralization time: 12 hours; mineralization gas: waste incineration flue gas (CO2 content: approximately 13%). After the mineralization reaction is completed, remove the aerated concrete block sample and cool it.

[0053] Comparative Example 3

[0054] The preparation method of the aerated concrete block sample of this comparative example is as follows:

[0055] (1) Using garbage incinerator slag (35%) (particle size <1mm) and fly ash (20%) as the main raw materials, and then adding a certain amount of high calcium steel slag (25%), lime (5%), and cement (15%), the raw materials are evenly mixed and then a certain amount of water (water / ash ratio = 0.65) is added. After stirring thoroughly, a small amount of foaming agent aluminum powder (1.5‰) is added, and stirring is continued thoroughly. Then, the mold is used for casting and molding, and the mold is demoulded after standing for 24 hours to obtain an aerated concrete block body;

[0056] (2) Place the demolded aerated concrete block in a high-pressure reactor for mineralization. Mineralization reaction conditions: 60°C; mineralization pressure: 1.6 MPa; mineralization time: 12 hours; mineralization gas: waste incineration flue gas (CO2 content: approximately 13%). After the mineralization reaction is completed, remove the aerated concrete block sample and cool it.

[0057] Comparative Example 4

[0058] The preparation method of the aerated concrete block sample of this comparative example is as follows:

[0059] (1) Preparation of aerated concrete block samples: waste incineration slag (30%) (particle size <1 mm) and fly ash (15%) are used as the main raw materials, and a certain amount of high-calcium steel slag (20%), lime (15%), and cement (20%) are added. After the raw materials are evenly mixed, a certain amount of water (water / ash ratio = 0.65) is added. After stirring thoroughly, a small amount of foaming agent aluminum powder (1.5‰) is added. Continue stirring thoroughly, and then use a mold to cast and shape. After standing for 24 hours, demouldation is performed to obtain aerated concrete block green body;

[0060] (2) Place the demolded aerated concrete block in a high-pressure reactor for mineralization. Mineralization reaction conditions: 60°C; mineralization pressure: 1.6 MPa; mineralization time: 12 hours; mineralization gas: waste incineration flue gas (CO2 content: approximately 13%). After the mineralization reaction is completed, remove the aerated concrete block sample and cool it.

[0061] Performance test of aerated concrete block samples

[0062] The bulk density, compressive strength and carbon fixation rate of the aerated concrete block samples prepared in Examples 1 to 6 and Comparative Examples 1 to 4 were tested respectively. The test methods are as follows:

[0063] Bulk density test: First, measure the length, width and height of the aerated concrete block sample respectively, with an accuracy of 1mm, and then calculate the volume of the specimen. Then, use a blast drying oven to dry the sample, and weigh the weight of the dried sample to calculate the corresponding bulk density (kg / m 3 );

[0064] Compressive strength test: A compression testing machine is used to test and analyze the compressive strength of aerated concrete block samples;

[0065] Carbon fixation rate test: A thermogravimetric analysis system is used to test the solidification rate of the solidified body after waste incineration.

[0066] Among them, the bulk density level of aerated concrete block samples refers to Table 1, the strength level refers to Table 2, and the test results are shown in Table 3.

[0067] Table 1. Dry density levels of masonry blocks (Autoclaved aerated concrete masonry block standard (GB11968-2006))

[0068]

[0069] Table 2. Strength levels of masonry blocks (Autoclaved aerated concrete masonry block standard (GB11968-2006))

[0070]

[0071] Table 3. Performance test results of aerated concrete block samples

[0072]

[0073] As can be seen from Table 3, based on the dry density (bulk density) level of the aerated concrete block samples, the compressive strength of the aerated concrete block samples of Comparative Examples 1-4 does not meet the strength requirements for the corresponding bulk density level. However, the aerated concrete block samples produced using the method of this embodiment maintain relatively excellent overall performance in bulk density, compressive strength, and carbon fixation rate, and meet the requirements of superior product (B) in the "Autoclaved Aerated Concrete Block Standard" (GB11968-2006).

[0074] The above examples are intended only to illustrate the detailed methods of the present invention. The present invention is not limited to the above detailed methods, nor does it mean that the present invention must rely on the above detailed methods to be implemented. Those skilled in the art will understand that any improvements to the present invention, equivalent replacements of raw materials for the products of the present invention, addition of auxiliary ingredients, and selection of specific methods, etc., all fall within the scope of protection and disclosure of the present invention.

Claims

1. A method for preparing aerated concrete blocks by mineralization of waste incineration flue gas, characterized in that: Based on the total mass fraction of 100%, 30%-40% of waste incineration slag, 10%-15% of fly ash, 20%-25% of steel slag, 5%-10% of lime and 20%-30% of cement are mixed to obtain a mixture; water and a foaming agent are added to the mixture, and an aerated concrete block body is obtained through stirring, pouring and demoulding; the aerated concrete block body is mineralized using a gas containing CO2 to obtain an aerated concrete block.

2. The method for preparing aerated concrete blocks by mineralization of waste incineration flue gas according to claim 1, characterized in that: The mass ratio of the water to the fly ash is 0.6-0.

7.

3. The method for preparing aerated concrete blocks by mineralization of waste incineration flue gas according to claim 1, characterized in that: The foaming agent is selected from aluminum powder.

4. The method for preparing aerated concrete blocks by mineralization of waste incineration flue gas according to claim 1, characterized in that: Based on the total mass of the mixture, the added amount of the foaming agent is 1‰-2‰.

5. The method for preparing aerated concrete blocks by mineralization of waste incineration flue gas according to claim 1, characterized in that: The mineralization treatment refers to placing the demoulded concrete block blanks in a high-pressure reactor and introducing the waste incineration flue gas to carry out a mineralization reaction.

6. The method for preparing aerated concrete blocks by mineralization of waste incineration flue gas according to claim 5, characterized in that: The temperature of the mineralization reaction is 55°C-65°C, the pressure is 1.5MPa-1.7MPa, and the time is 10h-15h.

7. The method for preparing aerated concrete blocks by mineralization of waste incineration flue gas according to claim 5, characterized in that: The mass fraction of CO2 in the waste incineration flue gas is 13%.

8. The method for preparing aerated concrete blocks by mineralization of waste incineration flue gas according to any one of claims 1 to 7, characterized in that: The casting and demoulding refer to casting and molding using a mold, and then standing for 20 hours to 36 hours before performing the demoulding treatment.

9. The method for preparing aerated concrete blocks by mineralization of waste incineration flue gas according to any one of claims 1 to 7, characterized in that: The particle size of the waste incineration slag is less than 1 mm.

10. An aerated concrete block, characterized in that: The aerated concrete blocks are prepared by the method for preparing aerated concrete blocks by mineralization of waste incineration flue gas as described in any one of claims 1 to 9, and the aerated concrete blocks meet the requirements of superior products (B) in standard number GB11968-2006.

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