A method for preparing desulfurized carbon by selecting refined carbon from gasified slag

Abstract

The present invention discloses a method for preparing desulfurized carbon by using gasification slag sorting fine carbon, comprising the following steps: (1) mixing gasification slag sorting fine carbon powder, lignite powder / long flame coal powder, and anthracite powder in a mass ratio of (65-80): (10-20): (10-15) to form a mixed powder; (2) adding a 20% potassium carbonate solution, high temperature coal tar and water to the mixed powder in sequence, wherein the mass ratio of the mixed powder, the 20% potassium carbonate solution, the high temperature coal tar and water is 1: (0.25-0.5): (0.1-0.3): 0.15, kneading evenly to form a coal paste; (3) subjecting the coal paste to molding, aging, carbonization and activation to obtain desulfurized carbon. The desulfurized carbon prepared by the method of the present invention has a dual-level pore structure of mesopores and micropores, and a large number of oxygen-containing functional groups are generated on the surface of the desulfurized carbon, so that it has the dual functions of adsorption and oxidation of sulfides.

Description

Technical Field

[0001] The present invention belongs to the field of comprehensive utilization of coal chemical solid waste. Specifically, the present application discloses a method for preparing desulfurized carbon by sorting refined carbon using gasification slag. Background Art

[0002] The utilization of coal mainly includes combustion for power generation and clean conversion of coal to chemical industry. my country's coal chemical industry is developing rapidly, among which coal gasification is the leading technology of modern coal chemical industry and the basis for the development of process industries such as coal-based chemicals, coal-based liquid fuels, IGCC power generation, cogeneration systems, hydrogen production and fuel cells.

[0003] The coal gasification process produces a large amount of solid waste - gasification slag. The gasification slag is divided into two categories: coarse slag and fine slag. The coarse slag is a low-melting-point eutectic in the coal ash that is quenched with water to form a broken glass body. It is discharged from the low-ash slag lock bucket of the gasifier and accounts for 60-80% of the total gasification slag. Its composition is similar to that of boiler ash and can be used as a mixed raw material for building materials, roads and bridges together with boiler ash. However, the gasification coarse slag produced by some furnace types or gasification processes has a high loss on ignition, which is greatly limited by its application. Fine slag is discharged with the flue gas in the form of fly ash. The flue gas is washed, purified and precipitated and then generates 20-40% of the total gasification slag. The loss on ignition is as high as 20-30%. It cannot be directly used as a building and road material. At present, it can only be landfilled or piled up, resulting in a waste of resources. The leakage of heavy metals will also cause soil and water pollution.

[0004] Coal gasification slag has a certain surface area and pore structure. It is a cheap and easily available special carbon source for preparing activated carbon and other adsorbent materials. How to make full use of the structural characteristics of gasification slag to prepare desulfurized carbon through pore structure and process parameter regulation and raw material blending, thereby broadening the source of raw materials for desulfurized carbon preparation and realizing the comprehensive utilization of solid waste resources has become a research focus in this field. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing desulfurized carbon by utilizing gasification slag sorting refined carbon. The desulfurized carbon prepared by the method of the present invention has a dual-level pore structure of mesopores and micropores, and at the same time, a large number of oxygen-containing functional groups are generated on the surface of the desulfurized carbon, so that it has the dual functions of adsorption and oxidation of sulfides, thereby achieving maximum improvement in the desulfurization performance and strength of the desulfurized carbon prepared by gasification slag sorting refined carbon.

[0006] According to an embodiment of the present invention, a method for preparing desulfurized carbon by separating clean carbon from gasified slag comprises the following steps:

[0007] (1) mixing the gasification slag sorting fine carbon powder, lignite powder / long flame coal powder, and anthracite powder in a mass ratio of (65-80): (10-20): (10-15) to form a mixed powder;

[0008] (2) adding a 20% potassium carbonate solution, high-temperature coal tar and water to the mixed powder in sequence, wherein the mass ratio of the mixed powder, the 20% potassium carbonate solution, the high-temperature coal tar and the water is: 1:(0.25-0.50):(0.1-0.3):0.15, and kneading them uniformly to form a coal paste;

[0009] (3) The coal paste is further subjected to molding, aging, carbonization and activation to obtain desulfurized carbon.

[0010] It can be understood that the lignite powder / long flame coal powder refers to a combination of one or both of lignite powder and long flame coal powder in any proportion.

[0011] In the preparation method of desulfurized carbon in the embodiment of the present invention, gasification slag sorted refined carbon, lignite / long flame coal, and anthracite are compounded. Anthracite is conducive to the formation of micropores during carbonization and activation, and lignite / long flame coal is conducive to improving the reaction activity of the system. At the same time, the low-priced and appropriate proportion of lignite / long flame coal can also increase the number of oxygen-containing functional groups in the system, which is conducive to improving the desulfurization effect of the desulfurized carbon product; gasification slag sorted refined carbon is conducive to improving the strength of the desulfurized carbon product. The mixture of gasification slag sorted refined carbon-lignite / long flame coal-anthracite (mainly sorted refined carbon) realizes the complementary advantages of the three.

[0012] In some embodiments, the mass ratio of the gasified slag sorting fine carbon powder, lignite powder / long flame coal powder, and anthracite powder is (70-80): (10-15): (10-15).

[0013] In some embodiments, the gasification slag sorting clean carbon powder is obtained by drying, crushing, grinding, and passing through a 200-mesh sieve to obtain the gasification slag sorting clean carbon powder; the lignite powder / long flame coal powder is obtained by drying, crushing, grinding, and passing through a 200-mesh sieve to obtain the lignite powder / long flame coal powder; the anthracite powder is obtained by drying, crushing, grinding, and passing through a 200-mesh sieve to obtain the anthracite powder.

[0014] In some embodiments, the gasification slag separation clean carbon is prepared by recovering carbon from the coal gasification slag produced by coal gasification, and the recovery method can adopt conventional processes, such as flotation, gravity separation, combustion, electrostatic separation, etc. Preferably, flotation is adopted.

[0015] In some embodiments, the ash content of the gasification slag sorted clean carbon is less than 10%, the ash content of the lignite / long flame coal is less than 10%, and the ash content of the anthracite is less than 10%. The embodiments of the present invention further improve the strength of the desulfurized carbon product and enhance the desulfurization performance of the desulfurized carbon product by controlling the ash content.

[0016] In some embodiments, the high temperature coal tar is a high temperature coal tar with an asphalt content of 68% to 70%. The high temperature coal tar with an asphalt content of 68% to 70% can be obtained by distilling conventional high temperature coal tar (55% to 60%) under normal pressure, or by heating and softening coal asphalt and then blending it with conventional high temperature coal tar.

[0017] The embodiment of the present invention preferably uses high-temperature coal tar with a high asphalt content (68-70%), which is easier to form a supporting skeleton and solidify during the carbonization and activation process, further improving the strength of the desulfurized carbon product.

[0018] In some embodiments, the high-temperature coal tar is first preheated to 80-90° C., and the water is preheated to 70-80° C. before being added to the mixed powder.

[0019] In some embodiments, the mass ratio of the mixed powder, 20% potassium carbonate solution, high-temperature coal tar and water is: 1:(0.3-0.4):(0.2-0.3):0.15.

[0020] In some embodiments, the kneading is performed in a mixer with heating at 80-90° C. (intensive mixing).

[0021] In some embodiments, the molding step is to extrude the coal paste in a hydraulic press to form the coal paste into a shape that is not limited to a smooth cylindrical, spherical, or granular shape.

[0022] In some embodiments, the aging step is to naturally air-dry the extruded coal paste for 2 to 3 days, with a water content of <10%, to form a carbonized precursor.

[0023] In some embodiments, the carbonization step is: nitrogen is passed through the system, the temperature is raised to 250°C at a heating rate of 8°C / min, then to 550°C at a heating rate of 3°C / min, and then to 650°C at a heating rate of 6°C / min, and the constant temperature time is 30 minutes.

[0024] In some embodiments, the activation step is: after carbonization, the temperature is raised to 850-900°C at a rate of 10°C / min, and when the temperature reaches 850-900°C, water vapor is introduced at 40 ml / h to start activation, and the activation time is 60-90 minutes.

[0025] The desulfurized carbon prepared by the method of the embodiment of the present invention has a mesoporosity of ≥41%, a microporosity of ≥55%, and a specific surface area of ​​≥600m 2 / g, sulfur content ≥37mg·g -1 , abrasion resistance ≥ 98%. It can be used for adsorption and removal of sulfur compounds in flue gas, or other waste gas desulfurization and purification fields.

[0026] The advantages and beneficial effects of the present invention are:

[0027] (1) In the preparation method of desulfurized carbon in the embodiment of the present invention, gasification slag sorted carbon, lignite / long flame coal, and anthracite are compounded. Anthracite is conducive to the formation of micropores during carbonization and activation, and lignite / long flame coal is conducive to improving the reaction activity of the system. At the same time, the appropriate proportion of lignite / long flame coal with low price can also increase the number of oxygen-containing functional groups in the system, which is conducive to improving the desulfurization effect of the desulfurized carbon product; gasification slag sorted carbon is conducive to improving the strength of the desulfurized carbon product. The mixture of gasification slag sorted carbon-lignite / long flame coal-anthracite (mainly sorted carbon) realizes the complementary advantages of the three.

[0028] (2) The embodiment of the present invention uses potassium carbonate as an activator, which is beneficial to the carbon activation pore formation and pore expansion reaction, and is beneficial to the increase of surface oxygen-containing functional groups, thereby improving the desulfurization performance of the product. It also does not corrode the carbonization equipment and activation equipment, decomposes in the high-temperature process, and hardly remains in the product. The desulfurized carbon product does not require a water washing process and no wastewater is generated, thereby improving the environmental performance of the entire process.

[0029] (3) The embodiment of the present invention preferably uses high-temperature coal tar with a high asphalt content (68-70%), which is easier to form a supporting skeleton and solidify during the carbonization and activation process, further improving the strength of the desulfurized carbon product.

[0030] (4) The carbonization process in the embodiment of the present invention adopts programmed temperature rise, which is conducive to the synergistic effect between different raw materials, especially in the temperature range of 250-550°C. The pyrolysis weight loss of different coals and tars in the raw materials is significant. At this time, the moderate heating rate can achieve the effect of moderate gas production, thereby inhibiting the formation of large pores without destroying the strength.

[0031] (5) The embodiments of the present invention realize the resource utilization of solid waste. The preparation of desulfurized carbon using gasification slag flotation refined carbon as raw material highlights the structural advantages of refined carbon, and explores a new path with broad market economic prospects for realizing the high-value resource utilization of coal gasification slag. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a SEM image of the desulfurized carbon prepared in Example 1 of the present invention.

[0033] Figure 2 It is the infrared spectrum of the desulfurized carbon prepared in Examples 1 and 2 of the present invention.

[0034] Figure 3 This is the adsorption isotherm diagram of the desulfurized carbon prepared in Example 1. DETAILED DESCRIPTION

[0035] Embodiments of the present invention are described in detail below. The embodiments described below are exemplary and intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0036] According to an embodiment of the present invention, a method for preparing desulfurized carbon by separating clean carbon from gasified slag comprises the following steps:

[0037] (1) mixing the gasification slag sorting fine carbon powder, lignite powder / long flame coal powder, and anthracite powder in a mass ratio of (65-80): (10-20): (10-15) to form a mixed powder;

[0038] (2) adding a 20% potassium carbonate solution, high-temperature coal tar and water to the mixed powder in sequence, wherein the mass ratio of the mixed powder, the 20% potassium carbonate solution, the high-temperature coal tar and the water is: 1:(0.25-0.50):(0.1-0.3):0.15, and kneading them uniformly to form a coal paste;

[0039] (3) The coal paste is further subjected to molding, aging, carbonization and activation to obtain desulfurized carbon.

[0040] It can be understood that lignite powder / long flame coal powder refers to a combination of one or both of lignite powder and long flame coal powder in any proportion.

[0041] Non-limiting examples include: the mass ratio of gasification slag sorting fine carbon powder, lignite powder / long flame coal powder, and anthracite powder can be: 80:10:10, 76:14:10, 75:15:10, 72:16:12, 70:20:10, 70:15:15, etc. The mass ratio of mixed powder, 20% potassium carbonate solution, high temperature coal tar and water can be: 1:0.3:0.3:0.15, 1:0.3:0.2:0.15, 1:0.35:0.3:0.15, 1:0.4:0.2:0.15, 1:0.45:0.3:0.15, 1:0.5:0.2:0.15, 1:0.5:0.3:0.15, etc.

[0042] In the preparation method of desulfurized carbon in the embodiment of the present invention, gasification slag sorted refined carbon, lignite / long flame coal, and anthracite are compounded. Anthracite is conducive to the formation of micropores during carbonization and activation, and lignite / long flame coal is conducive to improving the reaction activity of the system. At the same time, the low-priced and appropriate proportion of lignite / long flame coal can also increase the number of oxygen-containing functional groups in the system, which is conducive to improving the desulfurization effect of the desulfurized carbon product; gasification slag sorted refined carbon is conducive to improving the strength of the desulfurized carbon product. The mixture of gasification slag sorted refined carbon-lignite / long flame coal-anthracite (mainly sorted refined carbon) realizes the complementary advantages of the three.

[0043] In some embodiments, the gasification slag sorting clean carbon powder is obtained by drying, crushing, grinding, and passing through a 200-mesh sieve through the gasification slag sorting clean carbon; the lignite powder / long flame coal powder is obtained by drying, crushing, grinding, and passing through a 200-mesh sieve through the lignite / long flame coal; and the anthracite powder is obtained by drying, crushing, grinding, and passing through a 200-mesh sieve through the anthracite.

[0044] In some embodiments, the gasification slag separation clean carbon is prepared by recovering carbon from the coal gasification slag produced by coal gasification, and the recovery method can adopt conventional processes, such as flotation, gravity separation, combustion, electrostatic separation, etc. Preferably, flotation is adopted.

[0045] In some embodiments, the ash content of the gasified slag sorted clean carbon is less than 10%, the ash content of the lignite / long flame coal is less than 10%, and the ash content of the anthracite is less than 10%. The embodiments of the present invention further improve the strength of the desulfurized carbon product and enhance the desulfurization performance of the desulfurized carbon product by controlling the ash content.

[0046] In some embodiments, the high temperature coal tar is a high temperature coal tar with an asphalt content of 68-70%. The high temperature coal tar with an asphalt content of 68%-70% can be obtained by distilling conventional high temperature coal tar (55-60%) under normal pressure, or by heating and softening coal tar and then blending it with conventional high temperature coal tar. Non-limiting examples include: the asphalt content of the high temperature coal tar is 68%, 68.5%, 69%, 69.5%, 70%, etc.

[0047] The embodiment of the present invention preferably uses high-temperature coal tar with a high asphalt content (68-70%), which is easier to form a supporting skeleton and solidify during the carbonization and activation process, further improving the strength of the desulfurized carbon product.

[0048] In some embodiments, high temperature coal tar is preheated to 80-90° C., water is preheated to 70-80° C., and then added to the mixed powder.

[0049] In some embodiments, kneading is performed in a mixer with heating at 80-90° C. (intensive mixing).

[0050] In some embodiments, the molding step is to extrude the coal paste in a hydraulic press to form the coal paste into a shape that is not limited to a smooth cylindrical, spherical, granular, or the like.

[0051] In some embodiments, the aging step is to naturally air-dry the extruded coal paste for 2 to 3 days, with a water content of <10%, to form a carbonized precursor.

[0052] In some embodiments, the carbonization step is as follows: nitrogen is passed through the system, the temperature is increased to 250°C at a rate of 8°C / min, then to 550°C at a rate of 3°C / min, and then to 650°C at a rate of 6°C / min, and the temperature is kept constant for 30 minutes.

[0053] In some embodiments, the activation step is: after carbonization, the temperature is raised to 850-900°C at a rate of 10°C / min, and when the temperature reaches 850-900°C, water vapor is introduced at a rate of 40ml / h to start activation, and the activation time is 60-90min. Non-limiting examples include: the activation temperature can be 850°C, 860°C, 870°C, 885°C, 900°C, etc., and the activation time can be 60min, 70min, 75min, 80min, 85min, 90min, etc.

[0054] The desulfurized carbon prepared by the method of the embodiment of the present invention has a mesoporosity of ≥41%, a microporosity of ≥55%, and a specific surface area of ​​≥600m 2 / g, sulfur content ≥37mg·g -1 , abrasion resistance ≥ 98%. It can be used for adsorption and removal of sulfur compounds in flue gas, or other waste gas desulfurization and purification fields.

[0055] The technical solution of the present invention is further described below in conjunction with specific embodiments. The experimental methods without specific conditions in the embodiments are conventional methods and conventional conditions well known in the art.

[0056] The high temperature coal tar used in Examples 1 to 4 of the present invention has an asphalt content of 68% and a viscosity (E 80 ): 2.9, relative density (d4 20 ): 1.19, toluene insoluble matter: 4.0%, ash: 0.1%, moisture: 2%.

[0057] Example 1

[0058] A method for preparing desulfurized carbon by flotation of refined carbon from gasified slag, comprising the following steps:

[0059] (1) Flour milling and kneading

[0060] 8% ash content of gasified slag flotation fine carbon, 7.5% ash content of long flame coal, 5% ash content of anthracite are dried, crushed, ground, sieved, and passed through a 200-mesh sieve (particle size <0.074mm), and then the gasified slag flotation fine carbon powder, long flame coal powder, and anthracite powder are mixed and stirred at a mass ratio of 75:15:10 to form a mixed powder, and the mixed powder: 20% potassium carbonate solution: high temperature coal tar: water mass ratio is 1:0.3:0.3:0.15, and potassium carbonate solution, high temperature coal tar and water are added to the mixed powder in sequence, wherein the high temperature coal tar is preheated to 85°C, and the water is preheated to 80°C, and then vigorously kneaded in a kneader (heated to 80°C) to form a coal paste;

[0061] (2) Forming and aging

[0062] The coal paste is extruded into a smooth cylindrical shape in a hydraulic press and naturally dried for 3 days with a water content of 8.5% to form a carbonized precursor.

[0063] (3) Carbonization-activation

[0064] The system was passed through nitrogen and the temperature was raised to 250°C at a rate of 8°C / min, then to 550°C at a rate of 3°C / min, then to 650°C at a rate of 6°C / min, and the temperature was kept constant for 30 minutes. Then the system was raised to 900°C at a rate of 10°C / min. When the temperature was reached, water vapor was passed through at 40ml / h to start activation. The activation time was 90min. After the activation was completed, the water vapor was stopped and the nitrogen was continued to be passed through for cooling. The nitrogen was stopped until the temperature was below 150°C. The system was cooled naturally to obtain desulfurized carbon.

[0065] The SEM image of the desulfurized carbon prepared in Example 1 is as follows: Figure 1 As shown in the infrared spectrum Figure 2 As shown in the adsorption isotherm diagram, Figure 3 shown.

[0066] Example 2

[0067] A method for preparing desulfurized carbon by flotation of refined carbon from gasified slag, comprising the following steps:

[0068] (1) Flour milling and kneading

[0069] 8% ash content of gasified slag flotation fine carbon, 7.5% ash content of lignite, and 5% ash content of anthracite are dried, crushed, ground, sieved, and passed through a 200-mesh sieve (particle size <0.074 mm), and then the gasified slag flotation fine carbon powder, lignite powder, and anthracite powder are mixed and stirred at a mass ratio of 75:15:10 to form a mixed powder, and the potassium carbonate solution, high-temperature coal tar, and water are added to the mixed powder in sequence according to the mass ratio of the mixed powder: 20% potassium carbonate solution: high-temperature coal tar: water of 1:0.3:0.3:0.15, wherein the high-temperature coal tar is preheated to 85°C, and the water is preheated to 80°C, and then vigorously kneaded in a kneader (heated at 80°C) to form a coal paste;

[0070] (2) Forming and aging

[0071] The coal paste is extruded into a smooth cylindrical shape in a hydraulic press and naturally dried for 3 days with a water content of 8.5% to form a carbonized precursor.

[0072] (3) Carbonization-activation

[0073] The system was passed through nitrogen and the temperature was raised to 250°C at a rate of 8°C / min, then to 550°C at a rate of 3°C / min, then to 650°C at a rate of 6°C / min, and the temperature was kept constant for 30 minutes. Then the system was raised to 900°C at a rate of 10°C / min. When the temperature was reached, water vapor was passed through at 40ml / h to start activation. The activation time was 90min. After the activation was completed, the water vapor was stopped and the nitrogen was continued to be passed through for cooling. The nitrogen was stopped until the temperature was below 150°C. The system was cooled naturally to obtain desulfurized carbon.

[0074] The infrared spectrum of the desulfurized carbon prepared in Example 2 is as follows: Figure 2 shown.

[0075] Example 3

[0076] A method for preparing desulfurized carbon by flotation of refined carbon from gasified slag, comprising the following steps:

[0077] (1) Flour milling and kneading

[0078] 9% ash content of gasified slag flotation fine carbon, 5% ash content of long flame coal, and 5% ash content of anthracite are dried, crushed, ground, sieved, and passed through a 200-mesh sieve (particle size <0.074mm), and then the gasified slag flotation fine carbon powder, long flame coal powder, and anthracite powder are mixed and stirred at a mass ratio of 75:15:10 to form a mixed powder, and the mixed powder: 20% potassium carbonate solution: high temperature coal tar: water mass ratio is 1:0.3:0.1:0.15, and potassium carbonate solution, high temperature coal tar and water are added to the mixed powder in sequence, wherein the high temperature coal tar is preheated to 85°C, and the water is preheated to 80°C, and then strongly kneaded in a kneader (heated to 80°C) to form a coal paste;

[0079] (2) Forming and aging

[0080] The coal paste is extruded into a smooth cylindrical shape in a hydraulic press and naturally dried for 3 days with a water content of 8.5% to form a carbonized precursor.

[0081] (3) Carbonization-activation

[0082] The system was heated to 250°C at a rate of 8°C / min, then to 550°C at a rate of 3°C / min, then to 650°C at a rate of 6°C / min, and kept at this temperature for 30 minutes. The system was then heated to 860°C at a rate of 10°C / min. When the temperature was reached, water vapor was introduced at 40ml / h to start activation. The activation time was 90 minutes. After the activation, the water vapor was stopped and the nitrogen was continued to be passed for cooling. The nitrogen was stopped until the temperature was below 150°C. The system was then cooled naturally to obtain desulfurized carbon.

[0083] Example 4

[0084] A method for preparing desulfurized carbon by flotation of refined carbon from gasified slag, comprising the following steps:

[0085] 1) Flour milling and kneading

[0086] 8% ash content of gasified slag flotation fine carbon, 7.5% ash content of long flame coal, 5% ash content of anthracite are dried, crushed, ground, sieved, and passed through a 200-mesh sieve (particle size <0.074mm), and then the gasified slag flotation fine carbon powder, long flame coal powder, and anthracite powder are mixed and stirred at a mass ratio of 80:10:10 to form a mixed powder, and the mixed powder: 20% potassium carbonate solution: high temperature coal tar: water mass ratio is 1:0.5:0.3:0.15, and potassium carbonate solution, high temperature coal tar and water are added to the mixed powder in sequence, wherein the high temperature coal tar is preheated to 85°C, and the water is preheated to 80°C, and then vigorously kneaded in a kneader (heated to 80°C) to form a coal paste;

[0087] (2) Forming and aging

[0088] The coal paste is extruded into a smooth cylindrical shape in a hydraulic press and naturally dried for 3 days with a water content of 8.5% to form a carbonized precursor.

[0089] (3) Carbonization-activation

[0090] The system was heated to 250°C at a rate of 10°C / min, then to 550°C at a rate of 2°C / min, then to 650°C at a rate of 5°C / min, and kept at this temperature for 30 minutes. The system was then heated to 900°C at a rate of 10°C / min. When the temperature was reached, water vapor was introduced at 40ml / h to start activation. The activation time was 90 minutes. After the activation, the water vapor was stopped and the nitrogen was continued to be passed for cooling. The nitrogen was stopped until the temperature was below 150°C. The system was then cooled naturally to obtain desulfurized carbon.

[0091] Comparative Example 1:

[0092] The difference from Example 1 is:

[0093] The high temperature coal tar used has an asphalt content of 55%, a viscosity (E80): 2.5, a relative density (d420): 1.15, toluene insoluble matter: 3.5%, an ash content: 0.1%, and a moisture content: 2%.

[0094] The mass ratio of the mixed powder, 20% potassium carbonate solution, high-temperature coal tar and water is 1:0.30:0.05:0.15.

[0095] Comparative Example 2:

[0096] The difference from Example 1 is:

[0097] The ratio of gasification slag flotation fine carbon powder, long flame coal powder and anthracite powder is 80:15:5.

[0098] Comparative Example 3:

[0099] The difference from Example 1 is:

[0100] The ratio of gasification slag flotation fine carbon powder, long flame coal powder and anthracite powder is 85:5:10.

[0101] Comparative Example 4:

[0102] The difference from Example 1 is that no 20% potassium carbonate solution is added.

[0103] Comparative Example 5

[0104] The difference from Example 1 is:

[0105] In step (3), the system is supplied with nitrogen, and the temperature is raised to 650°C at a rate of 8°C / min, and the temperature is kept constant for 30 minutes. The temperature is then raised to 900°C at a rate of 10°C / min. When the temperature is reached, water vapor is introduced at 40 ml / h to start activation, and the activation time is 90 minutes. After the activation is completed, the water vapor is stopped, and the nitrogen is continued to be passed for cooling until the temperature is lower than 150°C, the nitrogen is stopped, and the temperature is naturally cooled to obtain desulfurized carbon.

[0106] It should be noted that the above comparative examples are not prior art and are only provided for comparison with the examples and are not intended to limit the present invention.

[0107] The test methods of the desulfurized carbon products of Examples 1 to 4 and Comparative Examples 1 to 5 of the present invention are shown in Table 1, and the test results are shown in Table 2. The desulfurized carbon in Table 2 is the SMK-101 desulfurized carbon product produced by Xia Shengmei Huarui Activated Carbon Manufacturing Co., Ltd.

[0108] Table 1 Desulfurization carbon product test method

[0109] Serial number project unit Standard No. 1 Iodine value mg / g GB / T 7702.7-2008 2 Abrasion resistance ％ GB / T 7702.3-2008 3 BET <![CDATA[m 2 / g]]> GB / T 19587-2004 4 Sulfur Capacity <![CDATA[ -1 ]]> GB / T 7702.14-2008

[0110] Table 2 Desulfurization carbon product test results

[0111]

[0112] Through Table 2, Figure 2 , Figure 3 It can be seen that:

[0113] (1) The method for preparing desulfurized carbon provided in the embodiment of the present invention has a dual-level pore structure with coexistence of mesopores and micropores, has the dual functions of adsorption and oxidation of sulfides, and improves the removal efficiency of sulfur-containing substances. Specifically, the desulfurized carbon product prepared by the method of the embodiment of the present invention has a mesoporosity of ≥41%, a microporosity of ≥55%, and a specific surface area of ​​≥600m 2 / g, sulfur content ≥37mg·g -1 , wear resistance ≥ 98%, with better comprehensive desulfurization performance.

[0114] (2) The infrared spectra of the finished desulfurized carbon obtained in Example 1 and Example 2 are as follows: Figure 2 As shown, from Figure 2 It can be seen that the main functional groups contained in the desulfurized carbon include -OH (3421cm -1 )、-CH2(2924cm -1 )、C=O(1572cm -1 ), proving the presence of carboxyl, anhydride or lactone groups on the surface of desulfurized carbon; at 1100cm-1150cm -1 A strong absorption peak appears at 1400 cm -1 The absorption peaks near can be attributed to the deformation vibration of OH. These functional groups have a positive effect on the removal reaction of sulfide.

[0115] (3) The adsorption isotherm of the desulfurized carbon prepared in Example 1 is as follows Figure 3 As shown, from Figure 3It can be seen that the adsorption-desorption isotherm of the finished desulfurized carbon rises rapidly at a lower relative pressure, and begins to flatten out at a relative pressure of about 0.1, and an H4-type hysteresis loop appears, proving that the desulfurized carbon contains both microporous and mesoporous structures. This isotherm belongs to the IV type isotherm, and the isothermal equilibrium adsorption capacity is 190 cm 3 / g, proving that the finished desulfurization carbon has many pores and excellent adsorption performance.

[0116] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0117] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for preparing desulfurized carbon by sorting refined carbon from gasified slag, characterized in that: The steps include: (1) Mix the gasification slag sorted fine carbon powder, lignite powder / long flame coal powder, and anthracite powder in a mass ratio of (65-80): (10-20): (10-15) to form a mixed powder; (2) adding a 20% potassium carbonate solution, high-temperature coal tar and water to the mixed powder in sequence, wherein the mass ratio of the mixed powder, the 20% potassium carbonate solution, the high-temperature coal tar and the water is: 1: (0.25-0.5): (0.1-0.3): 0.15, and kneading them evenly to form a coal paste; the high-temperature coal tar is a high-temperature coal tar with an asphalt content of 68%-70%; (3) the coal paste is further subjected to molding, aging, carbonization and activation to obtain desulfurized carbon; The carbonization step is as follows: nitrogen is passed through the system, the temperature is raised to 250°C at a rate of 8°C / min, then to 550°C at a rate of 3°C / min, then to 650°C at a rate of 6°C / min, and the temperature is kept constant for 30 minutes; The activation step is: after carbonization, the temperature is raised to 850-900°C at a rate of 10°C / min, and when the temperature reaches 850-900°C, water vapor is introduced at a rate of 40ml / h to start activation, and the activation time is 60-90min.

2. The method for preparing desulfurized carbon by selecting refined carbon from gasified slag according to claim 1, characterized in that: The mass ratio of the gasification slag sorting fine carbon powder, lignite powder / long flame coal powder and anthracite powder is (70-80): (10-15): (10-15).

3. The method for preparing desulfurized carbon by separating refined carbon from gasified slag according to claim 1, characterized in that: The mass ratio of the mixed powder, 20% potassium carbonate solution, high-temperature coal tar and water is: 1: (0.3-0.4): (0.2-0.3): 0.

15.

4. A method for preparing desulfurized carbon by separating refined carbon from gasified slag according to any one of claims 1 to 3, characterized in that: The gasification slag sorting clean carbon powder is obtained by drying, crushing, grinding and passing through a 200-mesh sieve to obtain the gasification slag sorting clean carbon powder; the lignite powder / long flame coal powder is obtained by drying, crushing, grinding and passing through a 200-mesh sieve to obtain the lignite powder / long flame coal powder; the anthracite powder is obtained by drying, crushing, grinding and passing through a 200-mesh sieve to obtain the anthracite powder.

5. The method for preparing desulfurized carbon by selecting refined carbon from gasified slag according to claim 4, characterized in that: The ash content of the gasification slag sorted clean carbon is less than 10%, the ash content of the lignite / long flame coal is less than 10%, and the ash content of the anthracite is less than 10%.

6. The method for preparing desulfurized carbon by selecting refined carbon from gasified slag according to claim 1, characterized in that: The high-temperature coal tar is preheated to 80-90° C., and the water is preheated to 70-80° C., and then added into the mixed powder.

7. The method for preparing desulfurized carbon by selecting refined carbon from gasified slag according to claim 1, characterized in that: The aging step is to naturally air-dry the extruded coal paste for 2 to 3 days, with a water content of <10%, to form a carbonized precursor.

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