CN110523366A - A molding method suitable for carbon capture sodium-based adsorbent - Google Patents

Abstract

The invention discloses a molding method suitable for carbon-capturing sodium-based adsorbents. The method comprises the steps of impregnating, drying, calcining and crushing the sodium-based adsorbents to obtain adsorbent particles, and then placing the granular adsorbent particles in It is fluidized and formed in a fluidized bed, and sieved to obtain the required particle size of the adsorbent; the fine powder collected in the fluidized bed is crushed again to a powder, mixed with water, dried, calcined, crushed, and then placed in the fluidized bed again. In the chemical bed, it can be recycled. Compared with the existing sodium-based adsorbent forming process, the forming method of the present invention is simple and convenient, and has high production efficiency.

Description

A molding method suitable for carbon capture sodium-based adsorbent

technical field

The invention relates to a molding method suitable for a carbon-capturing sodium-based adsorbent, which belongs to the field of carbon dioxide emission reduction.

Background technique

With the continuous development of industrialization, the excessive development and utilization of fossil energy has caused increasingly serious environmental problems. Environmental issues such as temperature rise caused by the greenhouse effect have attracted more and more attention. Among them, the increase of carbon dioxide (CO ₂ ) content in the air caused by the combustion of fossil fuels is an important factor of the greenhouse effect. Coal-fired power plants are the largest and most concentrated fixed single-point emission sources, and the development of carbon capture technologies suitable for coal-fired power plants is of great significance for mitigating the greenhouse effect.

Among the various _CO2 emission reduction technologies for power plants, alkali metal-based adsorbent decarbonization technology is considered to be extremely effective due to its advantages such as high recycling rate, low regeneration energy consumption, little corrosion to equipment, and no secondary pollution. One of the promising carbon capture technologies.

Under the funding of the U.S. Department of Energy (DOE), the Triangle Institute (RTI), Louisiana State University (LSU) and Cheche Dewey (C&D) used alkali metal or Alkaline earth metals are deposited on the support to capture _CO2 through decarburization and regeneration at 93-1093°C. In No. 6280603B1 (2001.08.28), an alkali metal carbonate cocatalyst and an adsorbent containing magnesium oxide were prepared by precipitation method, and CO ₂ was captured at 300-500°C. Korea Electric Power Corporation has applied for a patent in China: CN20041010564.0, which proposes to use spray drying method to prepare adsorbent particles. Domestic Southeast University has also carried out related research on this technology in recent years. In the CN200820037600.5 patent, a device for removing CO ₂ in flue gas by dry method with high-activity potassium-based absorbent is proposed, which can be organically integrated with coal-fired power generation systems. In combination, the coal-fired flue gas is used to provide the energy required by the system, effectively realizing the cascade utilization of energy. In the CN201810294379.X patent, it is suggested that the powdered sodium-based adsorbent is prepared by an equal-volume impregnation method, and then the adsorbent is modified by impregnating the other sodium-based/amine-based sub-active component solution to obtain a high-efficiency sodium-based solid adsorbent.

The above patents are aimed at improving the adsorption performance of the adsorbent or the adsorbent reaction system, but there are few reports on the molding technology of the sodium-based adsorbent. The Korea Electric Power Corporation proposed the method of spray drying, but due to this method, the active component load The amount is small and the particle size of the adsorbent is small, which has certain limitations on the fluidized bed. Therefore, for CO ₂ removal in power plants, a simple, convenient and efficient adsorbent molding technology is needed to ensure its industrial stable operation.

Contents of the invention

The present invention aims to provide a molding method suitable for carbon-capturing sodium-based adsorbents. The method can effectively reduce the wear phenomenon of the adsorbent during the carbon capture process, and is an optimized scheme for the stable industrial operation of the adsorbent.

The object of the present invention is to provide a molding method suitable for carbon capture sodium-based adsorbent, the method is specifically:

After pulverizing the activated alumina pellets, the activated alumina powder is slowly added to the sodium carbonate solution for immersion and stirring to obtain a semi-dry solid, which is dried and then calcined; the calcined adsorbent block solid is pulverized, and the adsorbent particles are fluidized After sieving, the fluidized adsorbent can be screened to obtain the required adsorbent;

After the fine powder eluting during the fluidization process continues to be pulverized, it is mixed with water and stirred, and then dried, calcined, crushed, fluidized and sieved to obtain the required adsorbent.

Further, the immersion stirring temperature was set to 40°C.

Further, the drying temperature is 110° C., and the drying time is 12 hours.

Further, the calcination temperature is 400°C, the heating rate is 3K/min, and the calcination time is 4h.

Further, the fluidization medium is air, the fluidization number is 2-3, and the fluidization time is 4-12 hours.

Compared with the prior art, the present invention has the following advantages:

1. The method of the present invention suitable for carbon capture sodium-based adsorbent is simple in process, convenient and fast; 2. The adsorbent particles prepared by the present invention have high sphericity, high strength, wear resistance, little corrosion to equipment, and adsorbent circulation High utilization rate.

Description of drawings

Figure 1 is (a) the SEM scanning electron micrograph of the crushed and formed adsorbent; (b) the SEM scanning electron micrograph of the fluidized and formed adsorbent.

Figure 2 is a comparison chart of the wear rate of adsorbents in different molding methods.

Fig. 3 is a process flow diagram of the present invention.

Detailed ways

Comparative example 1

1. Adsorbent Preparation

Take 660g of sodium carbonate and dissolve it in deionized water at 40°C to form a sodium carbonate solution. Take 1340g of activated alumina and grind it with a ball mill to obtain activated alumina powder, which is slowly added to the sodium carbonate solution, dipped and stirred under an electric mixer for 8 hours to obtain a semi-dry solid. The obtained semi-dry solid was dried in a drying oven at 110°C for 12h, and then calcined in a muffle furnace at 400°C for 4h at a heating rate of 3K/min. The obtained adsorbent block solid was crushed in a crusher, and the crushed The final adsorbent is sieved in a vibrating sieve machine to obtain the required adsorbent.

2. Wear rate test

Connect the test device required for the test, and check the device for air leakage. Weigh 200 g of the adsorbent with a particle size of 0.4-0.5 mm with an electronic balance and record it as M ₀ . Put the weighed adsorbent into the fluidized bed reactor, turn on the air compressor, and control the air flow rate to 2m ³ /h. After 4 hours, turn off the air compressor, take out the adsorbent, measure the mass of the adsorbent with an electronic balance and record M _i . Repeat the above steps, cycle test. The total fluidized wear time is 24h. And use the following formula (1) to calculate the wear rate of the adsorbent.

The attrition rate of the crushed adsorbent after 24 hours of wear on the fluidized bed is 0.79%/h.

Example 1

Take 660g of sodium carbonate and dissolve it in a certain amount of deionized water at 40°C to form a sodium carbonate solution. Take 1340g of activated alumina and grind it with a ball mill to obtain activated alumina powder, which is slowly added to the sodium carbonate solution, dipped and stirred under an electric mixer for 8 hours to obtain a semi-dry solid. The obtained semi-dry solid was dried in a drying oven at 110°C for 12h, then calcined in a muffle furnace at 400°C for 4h, the heating rate was 3K/min, and the obtained adsorbent block solid was crushed in a crusher to obtain The adsorbent particles are fluidized in the bubbling fluidized bed for 12 hours, and the fluidized adsorbent is sieved in a vibrating screen machine to obtain the required adsorbent. For the fine powder eluting in the bubbling fluidized bed, after being collected by the dust bag, it is placed in a ball mill and pulverized, and the obtained powder adsorbent is mixed with deionized water in an electric mixer, and then passed through the above adsorbent Through the preparation process, the required adsorbent can be obtained.

2. Wear rate test

Connect the test device required for the test, and check the device for air leakage. Weigh 200 g of the adsorbent with a particle size of 0.4-0.5 mm with an electronic balance and record it as M ₀ . Put the weighed adsorbent into the fluidized bed reactor, turn on the air compressor, and control the air flow rate to 2m ³ /h. After 4 hours, turn off the air compressor, take out the adsorbent, measure the mass of the adsorbent with an electronic balance and record M _i . Repeat the above steps, cycle test. The total fluidized wear time is 24h. And use the following formula (1) to calculate the wear rate of the adsorbent.

The wear rate of the crushed and shaped adsorbent after wearing in the fluidized bed for 24 hours is 0.35%/h

Example 2

Take 660g of potassium carbonate and dissolve it in deionized water at 40°C to form a potassium carbonate solution. Take 1340g of activated alumina and grind it with a ball mill to obtain activated alumina powder, which is slowly added to potassium carbonate solution, dipped and stirred under an electric mixer for 8 hours to obtain a semi-dry solid. The obtained semi-dry solid was dried in a drying oven at 110°C for 12h, then calcined in a muffle furnace at 400°C for 4h, the heating rate was 3K/min, and the obtained adsorbent block solid was crushed in a crusher to obtain The adsorbent particles are fluidized in the bubbling fluidized bed for 12 hours, and the fluidized adsorbent is sieved in a vibrating screen machine to obtain the required adsorbent. For the fine powder eluting in the bubbling fluidized bed, after being collected by the dust bag, it is placed in a ball mill and pulverized, and the obtained powder adsorbent is mixed with deionized water in an electric mixer, and then passed through the above adsorbent Through the preparation process, the required adsorbent can be obtained.

Claims (5)

1. a kind of forming method suitable for carbon capture sodium base adsorbent, which is characterized in that after activated alumina bead is crushed, Active alumina powder is slowly added to sodium carbonate liquor dipping stirring, leather hard solid is obtained and is dried, then calcine；It forges Adsorbent blocks of solid after burning is crushed, and absorbent particles are fluidized, and the adsorbent after fluidisation is sieved Obtain required adsorbent；

After the fine powder of elutriation continues crushing in fluid mapper process, then be mixed with water, drying, calcining, broken, stream Change and sieve, obtains required adsorbent.

2. the forming method of carbon capture sodium base adsorbent according to claim 1, which is characterized in that the dipping stirring Temperature is set as 40 DEG C.

3. the forming method of carbon capture sodium base adsorbent according to claim 1, which is characterized in that the drying temperature It is 110 DEG C, drying time 12h.

4. the forming method of carbon capture sodium base adsorbent according to claim 1, which is characterized in that the calcination temperature It is 400 DEG C, heating rate 3K/min, calcination time 4h.

5. the forming method of carbon capture sodium base adsorbent according to claim 1, which is characterized in that the fluidizing agent For air, fluidization number is 2~3, and the fluidisation time is 4~12h.