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CN-122006586-A - Selective catalytic denitration pyrolysis device for coupling carbon capture

CN122006586ACN 122006586 ACN122006586 ACN 122006586ACN-122006586-A

Abstract

The invention discloses a selective catalytic denitration pyrolysis device for coupling carbon capture, which comprises a shell, wherein a material distribution cavity, a pyrolysis cavity, a carbon capture cavity and an air collection cavity are sequentially arranged on the shell along the direction from top to bottom, a blanking pipe communicated with the material distribution cavity is arranged on the shell, the blanking pipe is used for enabling low-pressure air to carry ammonium carbamate powder into the material distribution cavity, the ammonium carbamate powder in the material distribution cavity is conveyed into the pyrolysis cavity to carry out pyrolysis and generate pyrolysis gas of carbon dioxide and ammonia, the carbon capture cavity is used for absorbing carbon dioxide in the pyrolysis gas exhausted from the pyrolysis cavity, the pyrolysis gas absorbed by the carbon capture cavity is conveyed into the air collection cavity, and the shell is provided with a pyrolysis gas outlet communicated with the air collection cavity. Compared with the ammonia preparation by urea, the ammonia preparation efficiency is improved by 4.2% -25.0%, the average ammonia preparation energy consumption is improved by 14.6%, the ammonia preparation energy consumption is reduced by 33.6% -43.2%, and meanwhile, the denitration efficiency of the generated mixed gas entering the flue gas selective catalytic denitration reactor can be improved by 3.0% -4.5%.

Inventors

  • LI YUZHE
  • ZHONG LI
  • ZHANG MAOLONG
  • ZHANG JIRUI
  • LIU LIANBO
  • LU DAYONG
  • SUN ZHONGHAO
  • QIN PENGFEI
  • WANG LIANGLIANG

Assignees

  • 北京华能长江环保科技研究院有限公司
  • 华能巢湖发电有限责任公司

Dates

Publication Date
20260512
Application Date
20260226

Claims (10)

  1. 1. A coupled carbon capture selective catalytic denitration pyrolysis device, comprising: The device comprises a shell (1), wherein a material distribution cavity (101), a pyrolysis cavity (102), a carbon capture cavity (103) and an air collection cavity (104) are sequentially arranged in the shell (1) along the direction from top to bottom, a blanking pipe (2) communicated with the material distribution cavity (101) is arranged on the shell (1), the blanking pipe (2) is used for carrying ammonium carbamate powder into the material distribution cavity (101) by low-pressure air, the ammonium carbamate powder in the material distribution cavity (101) is conveyed to the pyrolysis cavity (102) for pyrolysis and generating pyrolysis gas of carbon dioxide and ammonia, the carbon capture cavity (103) is used for adsorbing carbon dioxide in pyrolysis gas exhausted from the pyrolysis cavity (102), the pyrolysis gas adsorbed by the carbon capture cavity (103) is conveyed to the air collection cavity (104), and the shell (1) is provided with a pyrolysis gas outlet (105) communicated with the air collection cavity (104), and the gas outlet (105) is used for discharging the pyrolysis gas adsorbed by the pyrolysis gas.
  2. 2. The selective catalytic denitration pyrolysis device for coupling carbon capture according to claim 1, wherein the blanking pipe (2) comprises a same diameter section (201) and a variable diameter section (202), the same diameter section (201) is arranged outside the shell (1), the variable diameter section (202) is arranged in the distribution cavity (101), and the cross-sectional area of the variable diameter section (202) is gradually increased along the direction from top to bottom.
  3. 3. The selective catalytic denitration pyrolysis device coupled with carbon capture according to claim 1, further comprising a distribution plate (3), wherein the distribution plate (3) is arranged in the distribution cavity (101) and is located below the blanking pipe (2), the distribution plate (3) is provided with a plurality of distribution holes (301) which are arranged at intervals, and the aperture of the distribution holes (301) is 3mm-6mm.
  4. 4. The coupled carbon-trapping selective catalytic denitration pyrolysis device according to claim 1, further comprising a plurality of electric heating plates (4), the electric heating plates (4) being disposed in the pyrolysis chamber (102), the plurality of electric heating plates (4) being divided into a plurality of heating groups, the plurality of heating groups being arranged at intervals along a first direction, each heating group comprising a plurality of electric heating plates (4) arranged at intervals along a second direction, pyrolysis channels (5) extending in a vertical direction being defined between adjacent two of the electric heating plates (4), wherein the first direction, the second direction, and a height direction of the housing (1) are perpendicular to each other.
  5. 5. The coupled carbon-trapping selective catalytic denitration pyrolysis device of claim 4, wherein each of the heating groups is provided with insulation boards (6) on both sides of the first direction.
  6. 6. The selective catalytic denitration pyrolysis device coupled with carbon capture according to claim 1, wherein an insulating layer (7) is arranged on the inner peripheral wall of the shell (1).
  7. 7. The coupled carbon-trap selective catalytic denitration pyrolysis device according to claim 1, characterized in that the housing (1) has a feed pipe (8) and a discharge pipe (9), the feed pipe (8) being used for the entry of aqueous quicklime particles into the carbon-trap chamber, the discharge pipe (9) being used for the discharge of the carbon-trapped aqueous quicklime particles.
  8. 8. The selective catalytic denitration pyrolysis device coupled with carbon capture according to claim 7, further comprising a ventilation plate (10), wherein the ventilation plate (10) is arranged between the carbon capture chamber and the gas collection chamber, a plurality of ventilation holes (1001) through which heating and gas decomposition pass are formed in the ventilation plate (10), and one end of the discharge pipe (9) penetrates through the gas collection chamber (104) from the bottom of the shell (1) and extends into the carbon capture chamber (103).
  9. 9. The coupled carbon-trap selective catalytic denitration pyrolysis device according to claim 1, characterized in that low-pressure air carries ammonium carbamate powder into the blanking pipe (2) at a speed of 1.0m/s-3.0 m/s.
  10. 10. The coupled carbon-trap selective catalytic denitration pyrolysis device of claim 1, wherein a residence time of ammonium carbamate powder in the pyrolysis chamber (102) is 3.0s-5.0s, and a pyrolysis temperature in the pyrolysis chamber (102) is 120 ℃ to 160 ℃.

Description

Selective catalytic denitration pyrolysis device for coupling carbon capture Technical Field The invention relates to the technical field of flue gas denitration of coal-fired power plants, in particular to a selective catalytic denitration pyrolysis device for coupling carbon capture. Background In the SCR flue gas denitration process, the selection of a reducing agent is important. The most commonly used flue gas denitration reducing agent at present is urea. Urea ammonia production technology is relatively mature and high in safety, but needs to be performed under high-temperature conditions, which results in high energy consumption cost of the denitration system. In addition, carbon dioxide in mixed gas (comprising air, carbon dioxide, ammonia and the like) generated in the traditional urea thermal decomposition process directly enters a flue gas denitration system after untreated, and can be adsorbed on the surface of a catalyst in a competitive manner with reactants, especially in a high-concentration carbon dioxide environment, so that denitration efficiency can be reduced. In the related art, aiming at the limitations of the existing urea ammonia production technology, an intermediate product ammonium carbamate in urea production is provided as a main denitration agent component, and the method has the advantage of cost. However, ammonium carbamate is easy to agglomerate in the process of being applied to flue gas selective catalytic denitration, so that the problems of pipeline blockage, difficult decomposition and the like are caused. Disclosure of Invention The present invention aims to solve at least one of the technical problems in the related art to some extent. For this reason, the embodiment of the invention provides a selective catalytic denitration pyrolysis device coupled with carbon trapping. The selective catalytic denitration pyrolysis device for coupling carbon capture comprises a shell, wherein a distribution cavity, a pyrolysis cavity, a carbon capture cavity and an air collecting cavity are sequentially arranged on the shell along the direction from top to bottom, a blanking pipe communicated with the distribution cavity is arranged on the shell, the blanking pipe is used for enabling low-pressure air to carry ammonium carbamate powder into the distribution cavity, the ammonium carbamate powder in the distribution cavity is conveyed into the pyrolysis cavity to be pyrolyzed and generate pyrolysis gas of carbon dioxide and ammonia, the carbon capture cavity is used for adsorbing carbon dioxide in the pyrolysis gas discharged from the pyrolysis cavity, the pyrolysis gas adsorbed by the carbon capture cavity is conveyed into the air collecting cavity, and the shell is provided with a pyrolysis gas outlet communicated with the air collecting cavity, and the pyrolysis gas outlet is used for discharging the pyrolysis gas after adsorption. In some embodiments, the blanking pipe comprises a same diameter section and a variable diameter section, the same diameter section is arranged outside the shell, the variable diameter section is arranged in the distribution cavity, and the cross-sectional area of the variable diameter section is gradually increased along the direction from top to bottom. In some embodiments, the selective catalytic denitration pyrolysis device for coupling carbon capture further comprises a distributing plate, wherein the distributing plate is arranged in the distributing cavity and is positioned below the blanking pipe, the distributing plate is provided with a plurality of distributing holes which are arranged at intervals, and the aperture of each distributing hole is 3mm-6mm. In some embodiments, the selective catalytic denitration pyrolysis device coupled with carbon capture according to the embodiments of the present invention further includes a plurality of electric heating plates disposed in the pyrolysis chamber, the plurality of electric heating plates being divided into a plurality of heating groups, the plurality of heating groups being arranged at intervals along a first direction, each heating group including a plurality of electric heating plates arranged at intervals along a second direction, a pyrolysis channel extending in a vertical direction being defined between two adjacent electric heating plates, wherein the first direction, the second direction, and a height direction of the housing are perpendicular to each other. In some embodiments, each of the heating groups is provided with insulation boards on both sides of the first direction. In some embodiments, an insulating layer is provided on the inner peripheral wall of the housing. In some embodiments, the housing has a feed pipe for the aqueous quicklime particles to enter the carbon capture chamber and a discharge pipe for discharging the carbon-captured aqueous quicklime particles. In some embodiments, the selective catalytic denitration pyrolysis device for coupling carbon capture according t