A method for preparing carbon adsorption material by modifying industrial solid waste and accelerating carbonization

Abstract

The present invention discloses a method for preparing carbon adsorption materials by modifying industrial solid waste and accelerating carbonization, which belongs to the field of metallurgical technology and includes the following steps: preparing a carbonization precursor by using an admixture modification, a mixed pressing molding method, and preparing a carbon adsorption material by carbonization curing. The modification method adopted by the present invention can make full use of the waste heat from smelting, and obtain modified solid waste powder by adding a small amount of admixture modifier and controlling the cooling rate. The modified solid waste powder is mixed with water and pressed to obtain a carbonization precursor, and then the industrial waste CO2 gas is used to obtain a carbon adsorption material by a carbonization curing process. The material permanently seals CO2 and has extremely high compressive strength performance. It can be used for large-scale production of building materials such as sidewalk bricks, curbstones, and slope blocks, and has significant economic and ecological benefits.

Description

Technical Field

[0001] The invention belongs to the technical field of metallurgy, and in particular relates to a method for preparing a carbon adsorption material by modifying industrial solid waste and accelerating carbonization. Background Art

[0002] A large amount of solid waste is generated during the metallurgical production process. It has the disadvantages of poor activity and easy expansion when exposed to water. There is currently no effective way to treat it. The conventional practice of enterprises is to store it in piles or use a small amount as cement filler, but the mixing ratio in cement is low, which greatly limits the application of this industrial solid waste in cement. Some scholars say that Ca 2+ and Mg 2+ Under certain conditions, the mineral phase can react with CO2 to generate calcium carbonate particles. Studies have shown that the problems of the carbonization process mainly focus on how to improve the carbonization efficiency and the performance of the carbonized material. Scholars have conducted a lot of research on the above issues. At present, the carbonization methods can be divided into: dry carbonization, wet leaching carbonization and microbial carbonization. In addition, a large number of studies have reported the effects of various reaction parameters such as reaction time, liquid-solid ratio, temperature, additives, CO2 concentration, pressure, pH, etc. on the carbonization efficiency. At the same time, the microporous structure, stability, machinability and mechanical properties of the carbonized material are also discussed. However, there are still problems such as low carbonization efficiency of steel slag, high process implementation cost or low material added value, which have failed to achieve engineering application. Summary of the invention

[0003] Based on this, the present invention has developed a method for preparing carbon adsorption materials by modifying industrial solid waste and accelerating carbonization. By utilizing the waste heat from smelting, a small amount of additives is added to the hot industrial solid waste, and the modified solid waste powder is obtained by controlling the cooling rate. Combined with the method of pressing, molding, carbonization and curing, a carbon adsorption material with excellent performance is obtained.

[0004] The present invention adopts the following technical solutions:

[0005] A method for preparing a carbon adsorption material by modifying industrial solid waste and accelerating carbonization, comprising the following steps:

[0006] (1) The industrial solid waste is initially ground and mixed with an admixture and then subjected to modification treatment to obtain a modified sample;

[0007] (2) Grinding the modified sample to obtain modified solid waste powder;

[0008] (3) mixing the modified solid waste powder with water and pressing the mixture into a shape to obtain a carbonized precursor;

[0009] (4) Carbonizing and curing the carbonized precursor to obtain a carbon adsorption material.

[0010] Preferably, in step (1), the industrial solid waste is solid waste generated in a metallurgical production process. Based on the total mass of the industrial solid waste, the industrial solid waste components include CaO 40-50wt%, SiO2 22-26wt%, Fe2O3 8-10wt%, and MgO 10-13wt%. For example, based on the total mass of industrial solid waste, the industrial solid waste components include CaO 40 wt%, 42 wt%, 44 wt%, 46 wt%, 48 wt% or 50 wt%; SiO2 22 wt%, 22.5 wt%, 23 wt%, 23.5 wt%, 24 wt%, 24.5wt%, 25 wt%, 25.5 wt% or 26wt%; Fe2O3 8 wt%, 8.5 wt%, 9 wt%, 9.5 wt% or 10wt%; MgO 10wt%, 10.5 wt%, 11 wt%, 11.5 wt%, 12 wt%, 12.5 wt% or 13wt%.

[0011] Furthermore, in step (1), the water content of the industrial solid waste is below 5 wt%, preferably 4 wt%, and more preferably below 2 wt%.

[0012] Preferably, in step (1), the additive is one, two, three, four or five of BaO, Fe2O3, B2O3, Cr2O3 and ZnO.

[0013] Furthermore, in step (1), the amount of the admixture added is 0-10 wt% of the industrial solid waste, preferably 0-9 wt% of the industrial solid waste. For example, the amount of the admixture added is 0.05 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, or 9 wt% of the industrial solid waste.

[0014] Preferably, in step (1), the temperature of the modification treatment is 300-1200° C. For example, the temperature of the modification treatment is 300° C., 500° C., 700° C., 900° C., 1100° C., or 1200° C.

[0015] Furthermore, in step (1), the modification treatment is: directly heating to 900-1300°C at a rate of 3-20°C / min, isothermally heating for 30-180 minutes, and then cooling to room temperature at a rate of 3-20°C / min.

[0016] Preferably, in step (1), the isothermal time of the modification process is 60 to 120 minutes. For example, in step (1), the isothermal time of the modification process is 60 minutes, 70 minutes, 80 minutes, 90 minutes, 100 minutes, 110 minutes or 120 minutes.

[0017] Preferably, in step (1), the cooling rate of the modification treatment is 5 to 10°C / min. For example, in step (1), the cooling rate of the modification treatment is 5°C / min, 6°C / min, 7°C / min, 8°C / min, 9°C / min or 10°C / min.

[0018] Preferably, in step (2), the modified solid waste powder after grinding has a specific surface area of ​​800-4600 cm 2 For example, in step (2), the modified solid waste powder after grinding has a specific surface area of ​​800 cm 2 / g、1000 cm 2 / g, 1500 cm 2 / g, 2000 cm 2 / g, 2500 cm 2 / g、3000 cm 2 / g, 3500 cm 2 / g, 4000 cm 2 / g or 4600 cm 2 / g.

[0019] Preferably, in step (3), the solid-liquid mass ratio of the modified solid waste powder and water is 6:1 to 28:1. For example, in step (3), the solid-liquid mass ratio of the modified solid waste powder and water is 6:1, 8:1, 10:1, 12:1, 15:1, 20:1, 22:1, 24:1, 26:1 or 28:1.

[0020] Preferably, in step (3), the pressure of the press molding is 10-95 kN, and the time is 60-80 seconds. For example, in step (3), the pressure of the press molding is 10 kN, 20 kN, 30 kN, 40 kN, 50 kN, 60 kN, 70 kN, 80 kN or 95 kN, and the time is 60 seconds, 65 seconds, 70 seconds, 75 seconds or 80 seconds.

[0021] Preferably, in step (4), the carbonization curing conditions are: CO2 pressure of 100-600 kPa, temperature of 20-250°C, relative humidity of 60-100%, and carbonization time of 2-30 hours. For example, in step (4), the carbonization curing conditions are: CO2 pressure of 100 kPa, 200 kPa, 300 kPa, 400 kPa, 500 kPa or 600 kPa, temperature of 20°C, 40°C, 60°C, 80°C, 100°C, 150°C, 180°C, 200°C, 220°C or 250°C, relative humidity of 60%, 70%, 80%, 90%, 95% or 100%, and carbonization time of 2 hours, 5 hours, 10 hours, 15 hours, 20 hours, 25 hours or 30 hours.

[0022] The modification method adopted in the present invention can make full use of the waste heat from smelting. By adding a small amount of additives and controlling the cooling rate, modified solid waste powder is obtained. The modified solid waste powder is mixed with water and pressed into shape to obtain a carbonized precursor. The industrial waste CO2 gas is then used to obtain a carbon adsorption material through a carbonization curing process. The carbon adsorption material permanently seals CO2, which can greatly improve the carbon adsorption capacity of industrial solid waste, and prepare high-strength carbon adsorption building materials, which can be used in the large-scale production of building materials such as sidewalk bricks, curbstones and slope blocks, and has significant economic and ecological benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a process flow chart of the present invention for preparing carbon adsorption materials by modifying industrial solid waste and accelerating carbonization.

[0024] Figure 2 It is the compressive strength of the carbon adsorption materials prepared in Example 1, Example 2, Example 3, Example 4 and Example 5. DETAILED DESCRIPTION

[0025] The embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. The embodiments are implemented on the premise of the technical solution of the present invention, and detailed implementation methods and specific operation processes are given, but the protection scope of the present invention is not limited to the following embodiments.

[0026] like Figure 1 As shown, a method for preparing carbon adsorption materials by modifying industrial solid waste and accelerating carbonization comprises the following steps:

[0027] (1) After the industrial solid waste is initially ground and mixed with an admixture, it is subjected to a low-temperature (900-1300°C) modification treatment and cooled to obtain a modified sample;

[0028] (2) Grinding the modified sample to obtain modified solid waste powder;

[0029] (3) mixing the modified solid waste powder with water and pressing the mixture into a shape to obtain a carbonized precursor;

[0030] (4) The carbonized precursor is carbonized and cured using industrial waste CO2 to obtain a carbon adsorption material.

[0031] Example 1

[0032] The solid waste generated in the metallurgical production process is dried to obtain dried industrial solid waste. The dried industrial solid waste is ground to an average particle size of 75μm. Based on the total mass of the dried industrial solid waste, the main components of the dried industrial solid waste are CaO 44 wt%; SiO2 22.5 wt%; Fe2O3 10wt%; MgO 11.5 wt%, and the water content is 2wt%. The industrial solid waste is directly subjected to low-temperature modification treatment: the temperature is directly raised to 700℃ at a rate of 5℃ / min, and after isothermal for 1 hour, the temperature is lowered to room temperature at a rate of 5℃ / min in the furnace. After taking out the sample, it is ground by a ball mill to obtain a specific surface area of ​​3000±200 cm 2 / g of modified solid waste powder; the modified solid waste powder was mixed with water at a solid-liquid mass ratio of 20:1 and then placed in a 4×4×4 cm 3 A carbonized precursor is obtained by a pressing molding process in a mold, the pressing molding pressure is 75 kN, and the pressing molding time is 1 minute; the carbonized precursor is placed in a high-pressure carbonization reactor for carbonization treatment, and the carbonization treatment conditions are: the high-pressure carbonization reactor is a CO2 atmosphere, the CO2 pressure is 50 kPa, the temperature is 100°C, the relative humidity is 60%, and the carbonization time is 2 hours to obtain a carbon adsorption material.

[0033] Example 2

[0034] The preparation method is basically the same as that of Example 1, except that the industrial solid waste before low-temperature modification is uniformly mixed with a mixed admixture of B2O3 and BaO, wherein the mixing mass ratio of the B2O3 and BaO mixed admixture is 1:1, and the amount of the mixed admixture added is 5wt% of the mass of the industrial solid waste.

[0035] Example 3

[0036] The preparation method is basically the same as that of Example 2, except that the industrial solid waste before low-temperature modification is uniformly mixed with the admixture, and the amount of the admixture added is 8wt% of the mass of the industrial solid waste.

[0037] Example 4

[0038] The preparation method is basically the same as that of Example 2, except that the industrial solid waste before low-temperature modification is uniformly mixed with the admixture, and the amount of the admixture added is 10 wt % of the mass of the industrial solid waste.

[0039] Example 5

[0040] The preparation method is basically the same as that of Example 3, except that the low-temperature modification temperature is adjusted from 700°C to 800°C.

[0041] Test Case

[0042] The compressive strength of the carbon adsorption materials prepared in Examples 1, 2, 3, 4 and 5 was tested as follows: the compression machine was pressed at a rate of 2400 N / s ± 200 N / s until the material was broken. The compressive strength was measured in Newtons per square millimeter (MPa) and was calculated based on the maximum load at the time of failure and the area of ​​the compressed part. Figure 2 As shown. Figure 2 It can be seen that under the condition of low-temperature calcination at 700℃, when no mixed admixture is added, the compressive strength of the carbon adsorbent material is only 15.8 MPa. As the amount of mixed admixtures of B2O3 and BaO increases to 5 wt%, 8 wt% and 10 wt%, the compressive strength of the carbon adsorbent material first increases and then decreases, reaching a maximum strength of 124.5 MPa when the amount of mixed admixtures of B2O3 and BaO is 8 wt%. Taking the mixed admixture amount of B2O3 and BaO as 8 wt%, further increasing the calcination temperature to 800℃, the strength of the carbon adsorbent material is further increased to 155.6 MPa.

[0043] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing carbon adsorption materials by modifying industrial solid waste and accelerating carbonization, characterized in that: The following steps are involved: (1) After the industrial solid waste is initially ground, it is mixed with an admixture and then subjected to modification treatment to obtain a modified sample; (2) Grinding the modified sample to obtain modified solid waste powder; (3) mixing the modified solid waste powder with water and pressing the mixture into a shape to obtain a carbonized precursor; (4) carbonizing and curing the carbonized precursor to obtain a carbon adsorption material; In step (1), the admixture compounds are BaO and B2O3; the amount of the admixture added is 2-10wt% of the industrial solid waste; the temperature of the modification treatment is 200-1500°C, the heating rate of the modification treatment is 3-20°C / min; the isothermal time of the modification treatment is 10-300 minutes; the industrial solid waste is solid waste generated in the metallurgical production process, and based on the total mass of the industrial solid waste, the industrial solid waste components include CaO 40-60wt%, SiO2 20-30wt%, Fe2O3 5-15wt%, and MgO 5-15wt%; In step (4), the CO2 pressure of the carbonization curing is less than 600 kPa, the temperature is 10-300°C, the relative humidity is 50-100%, and the carbonization time is 1-30 hours.

2. The method according to claim 1, characterized in that: In step (1), the water content of the industrial solid waste is below 5 wt%.

3. The method according to claim 1, characterized in that: In step (1), the cooling rate of the modification treatment is 3-20°C / min.

4. The method according to claim 1, characterized in that: In step (2), the modified solid waste powder after grinding has a specific surface area of ​​500-5000 cm 2 / g.

5. The method according to claim 1, characterized in that: In step (3), the solid-liquid mass ratio of the modified solid waste powder mixed with water is 5:1 to 30:

1.

6. The method according to claim 1, characterized in that: In step (3), the pressing pressure is 10-100 kN and the time is 10-200 seconds.

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