Cement kiln tail flue gas SCR (selective catalytic reduction) denitration and ash removal device with scraper

Abstract

The invention discloses a cement kiln tail flue gas SCR denitration deashing device with scrapers, the cement kiln tail flue gas SCR denitration deashing device comprises a gas inlet pipe, a driving mechanism, a blowing mechanism and a plurality of scrapers, the driving mechanism is provided with the blowing mechanism, the blowing mechanism comprises a blowing main pipe and a plurality of blowing assemblies, the blowing main pipe is communicated with the blowing assemblies, and the blowing assemblies are communicated with the blowing main pipe. The air inlet pipe is communicated with the blowing main pipe, each blowing assembly is provided with a scraping plate, each blowing assembly comprises a plurality of communicating mechanisms, two blowing branch pipes and a plurality of spray heads, each blowing branch pipe is provided with a communicating mechanism communicated with the blowing branch pipe, the lower end of each blowing branch pipe is provided with a row of spray heads, and the spray heads are communicated with the communicating mechanisms. Compared with the prior art, the ash removal device has the advantages that the ash removal effect can be improved, meanwhile, the phenomena of hardening and accumulation on the surface of a catalyst can be effectively avoided, and long-term stable operation of SCR denitration at the tail of the cement kiln is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of flue gas treatment, in particular to a cement kiln tail flue gas SCR denitrification and ash cleaning device with a scraper. Background Art

[0002] The flue gas at the tail of cement kiln generally adopts high temperature and high dust SCR denitrification process. The SCR denitrification reactor is set between the C1 outlet and the waste heat boiler inlet. The flue gas at the tail of cement kiln contains a large amount of raw material dust, and the concentration is generally 80-120g / m3. The dust has the characteristics of small particle size, low density and strong adhesion. It is very easy to adhere to the surface of SCR denitrification catalyst, thereby causing catalyst blockage, poisoning or even failure.

[0003] In order to prevent the catalyst from failing, a rake soot blower is generally used for cleaning. Since there is not enough steam at the end of the cement kiln, heated compressed air is generally used for blowing. In actual use, due to insufficient compressed air pressure, the effect of blowing the catalyst is not good, and dust is still easy to accumulate on the catalyst surface, and even serious hardening may occur. The main reasons are that some nozzles are blocked, the compressed air pressure is insufficient, the compressed air humidity is high, and so on. Summary of the invention

[0004] The purpose of the present invention is to solve the problems in the prior art and to propose a cement kiln tail flue gas SCR denitrification and cleaning device with a scraper, which can improve the cleaning effect and effectively avoid the phenomenon of caking and accumulation on the catalyst surface, thereby ensuring the long-term stable operation of the cement kiln tail SCR denitrification.

[0005] To achieve the above-mentioned purpose, the present invention proposes a cement kiln tail flue gas SCR denitrification and ash cleaning device with a scraper, comprising an air intake pipe, a driving mechanism, a blowing mechanism and a plurality of scrapers, the driving mechanism is provided with a blowing mechanism, the blowing mechanism comprises a blowing main pipe and a plurality of blowing components, the blowing main pipe is connected with the blowing component, the air intake pipe is connected with the blowing main pipe, the blowing components are provided with scrapers, the blowing components include a plurality of connecting mechanisms, two blowing branches and a plurality of nozzles, the blowing branches are provided with connecting mechanisms connected thereto, the lower ends of the blowing branches are provided with nozzles arranged in a row, and the nozzles on the two blowing branches are staggered.

[0006] Preferably, the injection main pipe includes a main pipe I and a main pipe II, the connecting mechanism on the front injection branch pipe is connected to the main pipe I through a connecting pipe, and the connecting mechanism on the rear injection branch pipe is connected to the main pipe II through a connecting pipe. An electric three-way valve is provided at the output end of the intake pipe, and the two output ends of the electric three-way valve are respectively connected to the main pipe I and the main pipe II through a hose.

[0007] Preferably, the spray assembly also includes a shell, a connecting mechanism is provided at the upper end of the shell, the spray branch pipe is located inside the shell, the lower end of the shell is provided with through holes corresponding to and cooperating with the nozzles, two closing mechanisms are provided in the shell for closing the front and rear rows of through holes respectively, and a scraper is provided at the rear end of the shell.

[0008] Preferably, the closing mechanism comprises a plurality of seat bodies, a plurality of sliding rods, a plurality of springs III, a plurality of connecting rods and an L-shaped closing plate, the seat bodies are each provided with sliding rods, an L-shaped closing plate is provided at the rear end of the sliding rods, springs III are sleeved on the sliding rods between the L-shaped closing plate and the seat bodies, and the L-shaped closing plate is hingedly connected to the corresponding blowing branch pipe through a connecting rod.

[0009] Preferably, the connecting mechanism includes a piston sleeve, a piston, a shaft tube, an upper support, a spring I, a sealing head, a limit head, a lower support and a spring II. The piston sleeve is provided with an upper support and a lower support. A sliding shaft is passed through the upper support. A sealing head for closing the upper end of the shaft tube is provided at the lower end of the sliding shaft. A limit head is provided at the upper end of the sliding shaft. A spring I is sleeved on the sliding shaft between the sealing head and the upper support. A shaft tube is passed through the lower support. A piston matching the piston sleeve is provided at the upper end of the shaft tube. A spring II is sleeved on the shaft tube between the piston and the lower support.

[0010] Preferably, the driving mechanism comprises two linear guide rails, two L-shaped guide tubes, two flexible shaft cores, a ball screw, two screw nuts and a driving motor. The guide tubes are each provided with a flexible shaft core that matches the guide tubes. Both ends of the flexible shaft core are respectively connected to the slide table and screw nut of the corresponding linear guide rails through connecting heads. Both sides of the L-shaped guide tubes are provided with avoidance grooves for the corresponding connecting heads to slide. The ball screw is provided with two threaded sections, and both threaded sections are provided with screw nuts that match the guide tubes. The driving motor drives the ball screw to rotate.

[0011] The beneficial effects of the present invention are as follows: 1. A large amount of ash on the surface of the catalyst can be scraped into the catalyst holes by a scraper, and then taken away with the blowing and flue gas, which can effectively improve the cleaning effect; 2. When the accumulated ash is not blown off by the spray, the scraper can scrape off the accumulated ash, thereby avoiding long-term accumulation of ash on the catalyst surface, which leads to accelerated failure of the catalyst, and at the same time can effectively avoid long-term accumulation of ash leading to compaction, thereby affecting the normal use of the denitrification system; 3. The traditional row of nozzles arranged on the spray branch pipe is divided into two rows and the nozzles are staggered, so that the two rows of nozzles can work alternately, effectively reducing the number of working nozzles, thereby greatly improving the spraying force of the nozzles and improving the cleaning effect.

[0012] The features and advantages of the present invention will be described in detail through embodiments in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of a cement kiln tail flue gas SCR denitrification and ash cleaning device with a scraper according to the present invention; Figure 2 It is a partial side view of the blowing mechanism.

[0014] In the figure: 1-intake pipe, 2-driving mechanism, 3-spraying mechanism, 4-scraper, 21-linear guide rail, 22-L-shaped guide tube, 23-soft shaft core, 24-ball screw, 25-screw nut, 26-driving motor, 27-avoidance groove, 28-connector, 31-spraying main pipe, 32-spraying assembly, 311-main pipe I, 312-main pipe II, 313-connecting pipe, 314-electric three-way valve, 315-hose, 320-closing mechanism, 321-shell, 322-connecting mechanism, 323-blowing branch pipe, 324-nozzle, 325-through hole, 3201-seat body, 3202-sliding rod, 3203-spring III, 3204-connecting rod, 3205-L-shaped closing plate, 3220-sliding shaft, 3221-piston sleeve, 3222-piston, 3223-shaft tube, 3224-upper support, 3225-spring I, 3226-sealing head, 3227-limiting head, 3228-lower support, 3229-spring II. DETAILED DESCRIPTION

[0015] See also Figure 1 , Figure 2 The present invention discloses a cement kiln tail flue gas SCR denitrification and ash cleaning device with a scraper, comprising an air intake pipe 1, a driving mechanism 2, a blowing mechanism 3 and a plurality of scrapers 4, wherein the driving mechanism 2 is provided with a blowing mechanism 3, wherein the blowing mechanism 3 comprises a blowing main pipe 31 and a plurality of blowing components 32, wherein the blowing main pipe 31 is connected to the blowing components 32, wherein the air intake pipe 1 is connected to the blowing main pipe 31, wherein the blowing components 32 are provided with a scraper 4, wherein the blowing components 32 comprise a plurality of connecting mechanisms 322, two blowing branches 323 and a plurality of nozzles 324, wherein the blowing branches 323 are provided with connecting mechanisms 322 connected thereto, wherein the lower ends of the blowing branches 323 are provided with nozzles 324 arranged in a row, and the nozzles 324 on the two blowing branches 323 are arranged alternately.

[0016] The injection main pipe 31 includes a main pipe I311 and a main pipe II312. The connecting mechanism 322 on the front injection branch pipe 323 is connected to the main pipe I311 through a connecting pipe 313, and the connecting mechanism 322 on the rear injection branch pipe 323 is connected to the main pipe II312 through a connecting pipe 313. An electric three-way valve 314 is provided at the output end of the intake pipe 1. The two output ends of the electric three-way valve 314 are respectively connected to the main pipe I311 and the main pipe II312 through a hose 315.

[0017] The spray assembly 32 also includes a shell 321, a connecting mechanism 322 is provided at the upper end of the shell 321, the spray branch pipe 323 is located in the shell 321, and a through hole 325 corresponding to and cooperating with the nozzle 324 is provided at the lower end of the shell 321. Two closing mechanisms 320 are provided in the shell 321 for closing the front and rear rows of through holes 325 respectively, and a scraper 4 is provided at the rear end of the shell 321.

[0018] The closing mechanism 320 includes a plurality of seat bodies 3201, a plurality of slide rods 3202, a plurality of springs III3203, a plurality of connecting rods 3204 and an L-shaped closing plate 3205. The seat bodies 3201 are each provided with slide rods 3202. An L-shaped closing plate 3205 is provided at the rear end of the slide rods 3202. Springs III3203 are sleeved on the slide rods 3202 between the L-shaped closing plate 3205 and the seat bodies 3201. The L-shaped closing plate 3205 is hingedly connected to the corresponding blowing branch pipe 323 through the connecting rod 3204.

[0019] The connecting mechanism 322 includes a piston sleeve 3221, a piston 3222, a shaft tube 3223, an upper support 3224, a spring I3225, a sealing head 3226, a limit head 3227, a lower support 3228 and a spring II3229. The piston sleeve 3221 is provided with an upper support 3224 and a lower support 3228. A sliding shaft 3220 is passed through the upper support 3224. The lower end of the sliding shaft 3220 is provided with a sealing seal on the upper end of the shaft tube 3223. Head 3226, a limit head 3227 is provided at the upper end of the sliding shaft 3220, a spring I3225 is sleeved on the sliding shaft 3220 between the sealing head 3226 and the upper support 3224, a shaft tube 3223 is passed through the lower support 3228, a piston 3222 matched with the piston sleeve 3221 is sleeved on the upper end of the shaft tube 3223, and a spring II3229 is sleeved on the shaft tube 3223 between the piston 3222 and the lower support 3228.

[0020] The driving mechanism 2 includes two linear guide rails 21, two L-shaped guide tubes 22, two soft shaft cores 23, a ball screw 24, two screw nuts 25 and a driving motor 26. The guide tubes 22 are each provided with a soft shaft core 23 that matches therewith. Both ends of the soft shaft core 23 are respectively connected to the slide table and the screw nut 25 of the corresponding linear guide rail 21 through a connecting head 28. Both sides of the L-shaped guide tube 22 are provided with avoidance grooves 27 for the corresponding connecting head 28 to slide. The ball screw 24 is provided with two threaded sections, and both threaded sections are provided with a screw nut 25 that matches therewith. The driving motor 26 drives the ball screw 24 to rotate.

[0021] Working process of the present invention: During the operation of the cement kiln tail flue gas SCR denitrification and cleaning device with a scraper of the present invention, the drive motor 26 is started to drive the ball screw 24 to rotate clockwise first and then counterclockwise. When rotating clockwise, the ball screw 24 drives the two screw nuts 25 to move in the opposite direction and drives the slide of the corresponding linear guide 21 to move through the cooperation of the soft shaft core 23 and the connector 28. The slide of the linear guide 21 drives the blowing mechanism 3 and the scraper 4 thereon to move backward for cleaning operation. Then, when rotating counterclockwise, the ball screw 24 drives the two screw nuts 25 to move toward each other and drives the slide of the corresponding linear guide 21 to move through the cooperation of the soft shaft core 23 and the connector 28. The slide of the linear guide 21 drives the blowing mechanism 3 and the scraper 4 thereon to move forward for cleaning operation, which can effectively reduce the space occupied and has good adaptability to on-site installation.

[0022] The compressed air passes through the intake pipe 1, the electric three-way valve 314, the main pipeline I311 and the corresponding connecting pipe 313, the connecting mechanism 322, the blowing branch pipe 323 and the nozzle 324 in sequence, and then is blown to the catalyst. After the blowing mechanism 3 has traveled back and forth once, the compressed air passes through the intake pipe 1, the electric three-way valve 314, the main pipeline II312 and the corresponding connecting pipe 313, the connecting mechanism 322, the blowing branch pipe 323 and the nozzle 324 in sequence through the adjustment of the electric three-way valve 314, and then is blown to the catalyst.

[0023] When compressed air passes through the connecting mechanism 322, the piston 3222 drives the shaft tube 3223 to move downward under the action of compressed air and compresses the spring II3229. The shaft tube 3223 drives the corresponding blowing branch pipe 323 to move downward. The blowing branch pipe 323 pushes the L-shaped closing plate 3205 through the corresponding connecting rod 3204 to release the blocking of the corresponding through hole 325. The blowing branch pipe 323 moves downward and drives the nozzle 324 thereon to move downward and extend out of the through hole 325. During the downward movement of the piston 3222, the sealing head 3226 descends together with it under the action of the spring I3225. When the limit head 3227 is blocked by the upper support 3224, the sealing head 3226 cannot continue to move downward. At this time, the downward moving shaft tube 3223 is disengaged from the sealing head 3226, and compressed air enters the shaft tube 3223.

[0024] When the soot blowing is completed, the air supply to the air inlet pipe 1 stops, and the piston 3222 moves upward under the action of the spring II3229. The piston 3222 drives the corresponding blowing branch pipe 323 to move upward through the shaft tube 3223, and the blowing branch pipe 323 drives the nozzle 324 thereon to retract into the shell 321. When the shaft tube 3223 moves upward and presses on the sealing head 3226, the shaft tube 3223 pushes the sealing head 3226 to move upward and compresses the spring I3225. While the blowing branch pipe 323 pulls the connecting rod 3204 upward, the L-shaped closing plate 3205 moves toward the top of the corresponding through hole 325 under the action of the spring III3203 to block the through hole 325. In this way, the nozzle 324 is in a closed space, thereby avoiding the sealing failure caused by the nozzle 324 always being in the flue gas.

[0025] The above embodiments are intended to illustrate the present invention, not to limit the present invention. Any solution that is a simple transformation of the present invention belongs to the protection scope of the present invention.

Claims

1. A cement kiln tail flue gas SCR denitrification and ash cleaning device with a scraper, characterized by: The invention comprises an air intake pipe (1), a driving mechanism (2), a blowing mechanism (3) and a plurality of scrapers (4); the driving mechanism (2) is provided with a blowing mechanism (3); the blowing mechanism (3) comprises a blowing main pipe (31) and a plurality of blowing assemblies (32); the blowing main pipe (31) and the blowing assemblies (32) are both connected; the air intake pipe (1) is connected with the blowing main pipe (31); the blowing assemblies (32) are each provided with a scraper (4); the blowing assemblies (32) comprise a plurality of connecting mechanisms (322), two blowing branch pipes (323) and a plurality of nozzles (324); the blowing branch pipes (323) are each provided with a connecting mechanism (322) connected thereto; the lower ends of the blowing branch pipes (323) are each provided with nozzles (324) arranged in a row; the nozzles (324) on the two blowing branch pipes (323) are arranged in a staggered manner.

2. The SCR denitrification and ash cleaning device for flue gas from cement kiln tail with a scraper as claimed in claim 1, characterized in that: The injection main pipe (31) comprises a main pipe I (311) and a main pipe II (312); a connecting mechanism (322) on the front injection branch pipe (323) is connected to the main pipe I (311) via the connecting pipe (313); a connecting mechanism (322) on the rear injection branch pipe (323) is connected to the main pipe II (312) via the connecting pipe (313); an electric three-way valve (314) is provided at the output end of the air intake pipe (1); and both output ends of the electric three-way valve (314) are respectively connected to the main pipe I (311) and the main pipe II (312) via a hose (315).

3. The SCR denitrification and ash cleaning device for flue gas from cement kiln tail with a scraper as claimed in claim 1, characterized in that: The spray assembly (32) further comprises a shell (321), the upper end of the shell (321) being provided with a connecting mechanism (322), the spray branch pipe (323) being located inside the shell (321), the lower end of the shell (321) being provided with through holes (325) corresponding one-to-one with and cooperating with the spray heads (324), two closing mechanisms (320) being provided inside the shell (321) for closing two rows of through holes (325) respectively, and a scraper (4) being provided at the rear end of the shell (321).

4. The SCR denitrification and ash cleaning device for flue gas from cement kiln tail with a scraper as claimed in claim 3, characterized in that: The closing mechanism (320) comprises a plurality of seat bodies (3201), a plurality of sliding rods (3202), a plurality of springs III (3203), a plurality of connecting rods (3204) and an L-shaped closing plate (3205). The seat bodies (3201) are each provided with a sliding rod (3202). The rear end of the sliding rod (3202) is provided with an L-shaped closing plate (3205). The sliding rod (3202) between the L-shaped closing plate (3205) and the seat body (3201) is each provided with a spring III (3203). The L-shaped closing plate (3205) is hingedly connected to a corresponding blowing branch pipe (323) via a connecting rod (3204).

5. The SCR denitrification and ash cleaning device for flue gas from cement kiln tail with a scraper as claimed in claim 1, characterized in that: The communication mechanism (322) comprises a piston sleeve (3221), a piston (3222), a shaft tube (3223), an upper support (3224), a spring I (3225), a sealing head (3226), a limiting head (3227), a lower support (3228) and a spring II (3229). An upper support (3224) and a lower support (3228) are provided in the piston sleeve (3221). A sliding shaft (3220) is passed through the upper support (3224). A sealing member that seals the upper end of the shaft tube (3223) is provided at the lower end of the sliding shaft (3220). A sealing head (3226), a limit head (3227) is provided at the upper end of the sliding shaft (3220), a spring I (3225) is sleeved on the sliding shaft (3220) between the sealing head (3226) and the upper support (3224), a shaft tube (3223) is passed through the lower support (3228), a piston (3222) matching with the piston sleeve (3221) is sleeved on the upper end of the shaft tube (3223), and a spring II (3229) is sleeved on the shaft tube (3223) between the piston (3222) and the lower support (3228).

6. A cement kiln tail flue gas SCR denitrification and ash cleaning device with a scraper according to any one of claims 1 to 5, characterized in that: The driving mechanism (2) comprises two linear guide rails (21), two L-shaped guide tubes (22), two flexible shaft cores (23), a ball screw (24), two screw nuts (25) and a driving motor (26). The guide tubes (22) are each provided with a flexible shaft core (23) matched therewith. Both ends of the flexible shaft core (23) are respectively connected to the slide table and the screw nut (25) of the corresponding linear guide rails (21) through a connector (28). Both sides of the L-shaped guide tube (22) are provided with avoidance grooves (27) for the corresponding connector (28) to slide. The ball screw (24) is provided with two threaded sections. Both threaded sections are provided with a screw nut (25) matched therewith. The driving motor (26) drives the ball screw (24) to rotate.

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