Preparation method of CO2 adsorbent based on coal-based waste residues

Abstract

The invention discloses a preparation method of a CO2 adsorbent based on coal-based waste residues, which comprises the following steps: carrying out flotation on gasified ash residues to obtain refined carbon; mixing, crushing and screening the refined carbon and the calcium carbide alkaline residues to obtain a mixture; and uniformly mixing the mixture with residual oil to prepare a columnar profile material with the size of phi 2.5 mm * 10mm, and roasting at high temperature to obtain the CO2 adsorbent. Carrying out constant-temperature adsorption on the prepared gasified ash-residual oil-calcium carbide alkaline residue adsorbent, wherein the constant-temperature adsorption temperature is 700 DEG C; according to the method, a feasible method is provided for comprehensive utilization of gasification ash, catalytic cracking residual oil and calcium carbide alkali residues, economic benefits of coal gasification enterprises are increased, waste is turned into wealth, the obtained adsorbent reacts with CO2 through CaO, MgO and other active ingredients to adsorb and solidify CO2 on one hand, CO2 is adsorbed through activated carbon subjected to activation treatment on the other hand, and the CO2 is recycled. The absorption and solidification of CO2 are realized through the combined action.

Description

Technical Field

[0001] The present invention relates to the field of environmental protection technology, in particular to a CO 2 Method for preparing adsorbent. Background Art

[0002] The existing coal chemical industry in China has a daily coal input of 620,000 tons and a daily ash output of 93,000 tons, of which 65% is water-coal slurry gasification ash. With the rapid development of the coal gasification industry in recent years, the increasing emission of gasification ash needs to be solved urgently. At present, many domestic coal chemical enterprises have built landfills for their own use in accordance with the requirements of the "Pollution Control Standards for General Industrial Solid Waste Storage and Disposal Sites" to bury general solid wastes such as boiler ash and gasification slag. The advantages of this technology are relatively low investment, large processing capacity, and fast processing speed. The disadvantages are that it requires precious land resources. The permeate generated by the landfill is easy to pollute the water and soil, which puts great pressure on environmental protection work. At the same time, it also wastes a lot of coal resources, becoming a major problem restricting the sustainable development of the coal gasification industry base.

[0003] At present, flotation, spiral separation, heavy medium separation and other methods are used to recover residual carbon from gasification ash, but its products are mainly used as fuel for blast furnace injection, power plant coal blending, etc., and the economic benefits are not high. At the same time, since these energy and heavy chemical bases are usually large consumers of coal resources, energy consumption and CO 2 The emission intensity is high and the emission volume is large, so it is urgent to save energy and reduce consumption and CO 2 reduction and governance. Summary of the invention

[0004] To this end, the object of the present invention is to provide a CO 2 Preparation method of adsorbent, using gasification ash, residual oil and calcium carbide alkali residue as raw materials to prepare CO 2 Adsorbent, no additional activator is required during the production process, and the resulting CO 2 The adsorbent has good adsorption performance. On the one hand, the present invention can combine active ingredients such as CaO and MgO with CO 2 Reaction adsorption of CO 2 On the one hand, activated carbon absorbs CO 2 Through the above combined effects, CO 2 absorption and solidification.

[0005] In order to achieve the purpose of the above invention, the present invention provides the following technical solutions: A CO2-based coal-based waste 2 The preparation method of the adsorbent comprises the following steps: (1) Flotation of gasification ash obtained from the refinery to obtain refined carbon; (2) Mixing the refined carbon and calcium carbide alkali slag, and crushing and screening to obtain a mixture; (3) The mixture is mixed evenly with the residual oil to form a columnar material of Φ2.5mm×10mm, which is then roasted at high temperature to obtain CO 2 Adsorbent.

[0006] Preferably, the carbon content in the refined carbon is 81% to 83.55%.

[0007] Preferably, the Ca(OH) in the calcium carbide alkali slag 2 The mass fraction is 80% to 90%, 0 <Mg(OH) 2 <1%.

[0008] Preferably, the pulverization in step (2) is performed by using a ball mill, and the particle size of the mixture is ≦0.048 mm.

[0009] Preferably, the residual oil is produced in a catalytic cracking process and obtained after centrifugal separation pretreatment, with a content of colloid + asphaltene of 17.77% to 27.34% and a kinematic viscosity of 872.23 to 1091.00 mm 2 / s.

[0010] Preferably, the carbon content in the residual oil is 85.83% to 92.27%.

[0011] Preferably, the mass ratio of gasification ash:residual oil:calcium carbide alkali slag is (65-85):(5-10):(10-25).

[0012] Preferably, the high temperature calcination in step (3) is calcination at 700-850° C. in an air atmosphere for 60-180 min.

[0013] The CO based on coal-based waste 2 The adsorbent adsorbs CO 2 Application in.

[0014] Compared with the prior art, the present invention has the following advantages: (1) After gasification ash, residual oil and calcium carbide alkali slag are mixed and granulated, the calcium carbide alkali slag is decomposed under high temperature conditions to produce active components such as CaO and MgO; the gasification ash is activated by high temperature roasting to further improve its adsorption performance. The active components such as CaO and MgO and the activated gasification ash have a strong adsorption effect on CO 2 All have good adsorption and solidification effects; (2) High carbon content residual oil not only plays the role of bonding and forming carbon skeleton, but also improves the material basis of carbonization and activation; (3) Calcium carbide alkali slag plays the role of activator in the whole process and becomes a good CO after thermal decomposition. 2In addition, during the calcination and activation process, the calcium carbide alkali slag undergoes thermal cracking, and the gas produced by thermal cracking can increase the pore structure of the columnar activated carbon and improve the adsorption of CO by the activated carbon. 2 ability; (4) On the one hand, the present invention recycles the solid waste of coal chemical enterprises, thereby reducing environmental pollution; on the other hand, no additional activator needs to be added during the adsorbent production process, thereby reducing investment. DETAILED DESCRIPTION

[0015] Example 1 A CO2-based coal-based waste 2 The preparation method of the adsorbent comprises the following steps: (1) Obtain gasification ash from the refinery for flotation to obtain refined carbon; (2) Mix the refined carbon and calcium carbide alkali slag evenly, crush them with a ball mill, and screen out a mixture with a particle size of 0.030 mm; (3) The mixture was mixed evenly with the residual oil to form a columnar material of Φ2.5 mm×10 mm, which was calcined at 850°C in an air atmosphere for 180 min to obtain CO 2 Adsorbent; The carbon content of the refined carbon is 83.55%; The Ca(OH) in the calcium carbide alkali slag 2 The quality score is 90%; The residual oil is produced in the catalytic cracking process and obtained after centrifugal separation pretreatment. The carbon content of the residual oil is 92.27%, the content of colloid + asphaltene is 27.34%, and the kinematic viscosity is 1091.00mm 2 / s; The mass ratio of the gasification ash: residual oil: calcium carbide alkali residue is 70:5:25; The obtained adsorbent was effective for CO at 700℃. 2 The constant temperature adsorption capacity is 0.295gCO 2 / g adsorbent.

[0016] Example 2 A CO2-based coal-based waste 2 The preparation method of the adsorbent comprises the following steps: (1) Obtain gasification ash from the refinery for flotation to obtain refined carbon; (2) Mix the refined carbon and calcium carbide alkali slag evenly, crush them with a ball mill, and screen out a mixture with a particle size of 0.040 mm; (3) The mixture was mixed evenly with the residual oil to form a columnar material of Φ2.5 mm×10 mm, which was then calcined at 780°C in an air atmosphere for 60 min to obtain CO 2 Adsorbent; The carbon content in the refined carbon is 82%; The Ca(OH) in the calcium carbide alkali slag 2 The quality score is 82%; The residue oil is produced in the catalytic cracking process and obtained after centrifugal separation pretreatment. The carbon content of the residue oil is 89.93%, the content of colloid + asphaltene is 21.75%, and the kinematic viscosity is 1001.00mm 2 / s; The mass ratio of the gasification ash: residual oil: calcium carbide alkali slag is 80:6:14; The obtained adsorbent was effective for CO at 700℃. 2 The adsorption capacity at constant temperature is 0.278gCO 2 / g adsorbent.

[0017] Example 3 A CO2-based coal-based waste 2 The preparation method of the adsorbent comprises the following steps: (1) Obtain gasification ash from the refinery for flotation to obtain refined carbon; (2) Mix the refined carbon and calcium carbide alkali slag evenly, crush them with a ball mill, and screen out a mixture with a particle size of 0.045 mm; (3) The mixture was mixed evenly with the residual oil to form a columnar material of Φ2.5 mm×10 mm, which was then calcined at 800°C in an air atmosphere for 120 min to obtain CO 2 Adsorbent; The carbon content in the refined carbon is 82%; The Ca(OH) in the calcium carbide alkali slag 2 The quality score is 85%; The residue oil is produced in the catalytic cracking process and obtained after centrifugal separation pretreatment. The carbon content of the residue oil is 85.83%, the content of colloid + asphaltene is 17.80%, and the kinematic viscosity is 915.00mm 2 / s; The mass ratio of the gasification ash residue: residual oil: calcium carbide alkali residue is 80:10:10; The obtained adsorbent was effective for CO at 700℃. 2 The constant temperature adsorption capacity is 0.289gCO 2 / g adsorbent.

[0018] Example 4 A CO2-based coal-based waste 2 The preparation method of the adsorbent comprises the following steps: (1) Obtain gasification ash from the refinery for flotation to obtain refined carbon; (2) Mix the refined carbon and calcium carbide alkali slag evenly, crush them with a ball mill, and screen out a mixture with a particle size of 0.048 mm; (3) The mixture was mixed evenly with the residual oil to form a columnar material of Φ2.5 mm×10 mm, which was then calcined at 700°C in an air atmosphere for 60 min to obtain CO 2 Adsorbent; The carbon content in the refined carbon is 81%; The Ca(OH) in the calcium carbide alkali slag 2 The quality score is 80%; The residual oil is produced in the catalytic cracking process and obtained after centrifugal separation pretreatment. The carbon content of the residual oil is 85.83%, the content of colloid + asphaltene is 17.77%, and the kinematic viscosity is 872.23mm 2 / s; The mass ratio of the gasification ash: residual oil: calcium carbide alkali slag is 85:5:10; The obtained adsorbent was effective for CO at 700℃. 2 The adsorption capacity at constant temperature is 0.274gCO 2 / g adsorbent.

[0019] Example 5 A CO2-based coal-based waste 2 The preparation method of the adsorbent comprises the following steps: (1) Obtain gasification ash from the refinery for flotation to obtain refined carbon; (2) Mix the refined carbon and calcium carbide alkali slag evenly, crush them with a ball mill, and screen out a mixture with a particle size of 0.040 mm; (3) The mixture was mixed evenly with the residual oil to form a columnar material of Φ2.5 mm×10 mm, which was calcined at 750°C in an air atmosphere for 120 min to obtain CO 2 Adsorbent; The carbon content in the refined carbon is 82%; The Ca(OH) in the calcium carbide alkali slag 2 The quality score is 82%; The residue oil is produced in the catalytic cracking process and obtained after centrifugal separation pretreatment. The carbon content of the residue oil is 89.93%, the content of colloid + asphaltene is 21.75%, and the kinematic viscosity is 1001.00mm 2 / s; The mass ratio of the gasification ash: residual oil: calcium carbide alkali slag is 65:10:25; The obtained adsorbent was effective for CO at 700℃. 2 The adsorption capacity at constant temperature is 0.285gCO 2 / g adsorbent.

[0020] Obviously, the above embodiments are merely examples for clear explanation, and are not intended to limit the implementation methods. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from this are still within the scope of protection of the claims of this patent application.

Claims

1. A method for preparing a CO2 adsorbent based on coal-based waste residue, characterized in that: The following steps are involved: (1) flotation of gasification ash to obtain refined carbon; (2) mixing the refined carbon and the calcium carbide alkali slag, crushing and screening to obtain a mixture; (3) The mixture is mixed evenly with the residual oil to form a columnar material of Φ2.5mm×10mm, and then calcined at high temperature to obtain a CO2 adsorbent.

2. A method for preparing a CO2 adsorbent based on coal-based waste residue according to claim 1, characterized in that: The carbon content in the refined carbon is 81% to 83.55%.

3. A method for preparing a CO2 adsorbent based on coal-based waste residue according to claim 1, characterized in that: The mass fraction of Ca(OH)2 in the calcium carbide alkali slag is 80% to 90%, and 0<Mg(OH)2<1%.

4. A method for preparing a CO2 adsorbent based on coal-based waste residue according to claim 1, characterized in that: The pulverization in step (2) is performed by using a ball mill, and the particle size of the mixture is ≤ 0.048 mm.

5. A method for preparing a CO2 adsorbent based on coal-based waste residue according to claim 1, characterized in that: The residual oil is produced in the catalytic cracking process and obtained after centrifugal separation pretreatment. The content of colloid + asphaltene is 17.77% to 27.34%, and the kinematic viscosity is 872.23 to 1091.00 mm 2 / s.

6. A method for preparing a CO2 adsorbent based on coal-based waste residue according to claim 5, characterized in that: The carbon content of the residual oil is 85.83% to 92.27%.

7. A method for preparing a CO2 adsorbent based on coal-based waste residue according to claim 1, characterized in that: The mass ratio of the gasification ash residue: residual oil: calcium carbide alkali residue is (65-85): (5-10): (10-25).

8. A method for preparing a CO2 adsorbent based on coal-based waste residue according to claim 1, characterized in that: The high temperature calcination in step (3) is calcination at 700-850°C for 60-180 minutes.

9. Use of a CO2 adsorbent based on coal-based waste residue as described in claims 1-7 in adsorbing CO2.