CN-122006588-A - Selective catalytic denitration pyrolysis device for coupling carbon capture

CN122006588ACN 122006588 ACN122006588 ACN 122006588ACN-122006588-A

Abstract

The invention discloses a coupling carbon capture selective catalytic denitration pyrolysis device which comprises an outer cylinder body, a pyrolysis cylinder and a drying cylinder, wherein the outer cylinder body extends along the vertical direction, a first sealing plate is arranged at the top end opening of the outer cylinder body, a second sealing plate is arranged at the bottom end opening of the outer cylinder body, the pyrolysis cylinder is used for pyrolyzing ammonium carbamate powder and generating pyrolysis gas of carbon dioxide and ammonia, the drying cylinder stretches into the outer cylinder body from the second sealing plate and is communicated with the outer cylinder body in a limiting manner, a carbon capture cavity and a water washing cavity are arranged in the vertical direction, the carbon capture cavity is used for adsorbing carbon dioxide in the pyrolysis gas, a solid outlet is arranged at the second sealing plate and is used for discharging sediment in the water washing cavity, and a drying agent is arranged in the drying cylinder. Compared with the ammonia preparation by urea, the ammonia preparation efficiency is improved by 6.4% -28%, the average ammonia preparation efficiency is improved by 17.2%, the ammonia preparation energy consumption is reduced by 33.2% -42.6%, and meanwhile, the denitration efficiency of the generated mixed gas entering the flue gas selective catalytic denitration reactor can be improved by 3.5% -4.5%.

Inventors

LI YUZHE
ZHANG JIRUI
QIN PENGFEI
LI WEI
LIU LIANBO
LU DAYONG
LI NAN
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. A coupled carbon capture selective catalytic denitration pyrolysis device, comprising: The outer cylinder body (1), the outer cylinder body (1) extends along the vertical direction, a first sealing plate (2) is arranged at the top end opening of the outer cylinder body (1), and a second sealing plate (3) is arranged at the bottom end opening of the outer cylinder body (1); The pyrolysis cylinder (4), the pyrolysis cylinder (4) stretches into the outer cylinder body (1) from the first sealing plate (2) and a heating cavity (5) is defined between the pyrolysis cylinder and the outer cylinder body (1), an electric heating component (6) is arranged in the pyrolysis cavity, and the pyrolysis cylinder (4) is used for pyrolyzing ammonium carbamate powder and generating pyrolysis gas of carbon dioxide and ammonia; A drying cylinder (7), the drying cylinder (7) extends into the outer cylinder body (1) from the second sealing plate (3) and is communicated with the outer cylinder body (1) to define a carbon trapping cavity (8) and a water washing cavity (9) which are arranged in the up-down direction and are communicated, the carbon trapping cavity (8) is positioned above the water washing cavity (9), the outer cylinder body (1) is provided with a lime water inlet (101) and a lime water outlet (102), the lime water inlet (101) is communicated with the carbon trapping cavity (8), the lime water outlet (102) is communicated with the water washing cavity (9), the carbon trapping cavity (8) is used for adsorbing carbon dioxide in pyrolysis gas, the second sealing plate (3) is provided with a solid outlet (301) for discharging sediment in the water washing cavity (9), the peripheral wall of the drying cylinder (7) is provided with a 701 communicated with the water washing cavity (9), the top end of the drying cylinder (7) is provided with a lime water inlet (101) and the drying cylinder (7) is provided with a third sealing plate (10), the drying cylinder (7) is provided with a drying agent (701) and the drying cylinder (7) enters the pyrolysis cylinder (7) through the drying cylinder (7), and the pyrolysis gas after drying the drying agent (11) is discharged through the pyrolysis gas outlet (702).
2. The coupled carbon-trapping selective catalytic denitration pyrolysis device according to claim 1, wherein the electric heating assembly (6) comprises a plurality of heating rods (601) and a heat accumulator (602), the heat accumulator (602) fills the heating cavity (5), the plurality of heating rods (601) are arranged at intervals along the circumferential direction of the outer cylinder (1), and at least part of the heating rods (601) are inserted in the heat accumulator (602).
3. The selective catalytic denitration pyrolysis device coupled with carbon capture according to claim 1, characterized in that the carbon capture cavity (8) is filled with an inert particle layer (12).
4. The selective catalytic denitration pyrolysis device coupled with carbon capture according to claim 1, comprising a baffle plate (13) arranged in the washing cavity (9), wherein the baffle plate (13) comprises a first plate body (1301) and a second plate body (1302), one end of the first plate body (1301) is connected with the peripheral wall of the drying cylinder (7) and extends along the radial direction of the drying cylinder (7), the second plate body (1302) is connected with the second end of the first plate body (1301), the second plate body (1302) extends downwards along the axial direction of the drying cylinder (7), and a baffle channel (14) is defined between the baffle plate (13) and the drying cylinder (7).
5. The coupled carbon capture selective catalytic denitration pyrolysis device of claim 1, wherein the number of the slaked lime water inlet (101) and the slaked lime water outlet (102) are multiple and are arranged at intervals along the circumference of the outer cylinder (1).
6. The coupled carbon capture selective catalytic denitration pyrolysis device of claim 1 wherein low pressure air carries ammonium carbamate powder into the pyrolysis drum (4) at a rate of 1.0m/s to 3.0m/s for pyrolysis.
7. The coupled carbon-trap selective catalytic denitration pyrolysis device according to claim 1, characterized in that the residence time of ammonium carbamate powder in the pyrolysis drum (4) is 3.0s-5.0s.
8. The coupled carbon-trap selective catalytic denitration pyrolysis device of claim 7, wherein the pyrolysis temperature within the pyrolysis drum (4) is 200-240 ℃.
9. The coupled carbon capture selective catalytic denitration pyrolysis device of claim 1, wherein the desiccant (11) is quicklime particles of 5mm-8 mm.
10. The coupled carbon capture selective catalytic denitration pyrolysis device according to claim 1, wherein the ratio of the height and diameter of the outer cylinder (1) is (4.0-5.0): 1.0, and the width of the heating chamber (5) is 1/4-1/3 of the diameter of the outer cylinder (1).

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 an outer cylinder body, a pyrolysis cylinder and a drying cylinder, wherein the outer cylinder body extends along the vertical direction, a first sealing plate is arranged at the top end opening of the outer cylinder body, and a second sealing plate is arranged at the bottom end opening of the outer cylinder body; The pyrolysis cylinder stretches into the outer cylinder body from the first sealing plate, a heating cavity is defined between the pyrolysis cylinder and the outer cylinder body, an electric heating component is arranged in the pyrolysis cavity, and the pyrolysis cylinder is used for pyrolyzing ammonium carbamate powder and generating pyrolysis gas of carbon dioxide and ammonia; The drying cylinder stretches into the outer cylinder body from the second sealing plate and is communicated with the outer cylinder body to define a carbon trapping cavity and a water washing cavity which are arranged in the vertical direction, the carbon trapping cavity is located above the water washing cavity, the outer cylinder body is provided with a lime water inlet and a lime water outlet, the lime water inlet is communicated with the carbon trapping cavity, the lime water outlet is communicated with the water washing cavity, the carbon trapping cavity is used for adsorbing carbon dioxide in pyrolysis gas, the second sealing plate is provided with a solid outlet for discharging sediment in the water washing cavity, the peripheral wall of the drying cylinder is provided with a vent hole communicated with the water washing cavity, the top end opening of the drying cylinder is provided with a third sealing plate, the bottom end opening of the drying cylinder forms a pyrolysis gas outlet, a drying agent is arranged in the drying cylinder, pyrolysis gas in the water washing cavity enters the drying cylinder through the vent hole, and the pyrolysis gas after the drying agent is dried is discharged through the pyrolysis gas outlet. In some embodiments, the electric heating assembly includes a plurality of heating rods and a heat accumulator, the heat accumulator filling the heating cavity, the plurality of heating rods being arranged at intervals along the circumference of the outer cylinder, at least part of the heating rods being inserted in the heat accumulator. In some embodiments, the carbon capture cavity is filled with a layer of inert particles. In some embodiments, the selective catalytic denitration pyrolysis device for coupling carbon capture according to the embodiments of the present invention includes a baffle plate disposed in the water washing chamber, where the baffle plate includes a first plate body and a second plate body, one end of the first plate body is connected to an outer peripheral wall of the drying cylinder and extends in a radial direction of the drying cylinder, the second plate body is connected to a second end of the first plate body, the second plate body extends downward in an axial direction of the drying cylinder, and a baffle channel is defined between the baffle plate and the drying c