Energy-saving and anti-blocking catalyst purging device and method
By combining a low-pressure Roots blower and a gas-to-gas heat exchanger with a Venturi nozzle design, the problem of catalyst ash accumulation and blockage is solved, achieving efficient purging, reducing energy consumption, extending catalyst life, and improving denitrification efficiency.
Patent Information
- Application Number
- CN202610298967.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-03-12
- Publication Date
- 2026-06-19
AI Technical Summary
In existing technologies, catalysts are prone to ash accumulation and blockage, leading to a decrease in denitrification efficiency. Furthermore, high-pressure airflow washes away and wears the catalyst, increasing energy consumption and equipment investment. Nozzles are also prone to rust and slag blockage, resulting in poor sootblowing performance.
The system employs a low-pressure Roots blower and a gas-to-gas heat exchanger, with a Venturi nozzle designed to match the catalyst orifice. A filter tube is added to prevent impurities from entering. High-temperature medium is used for purging, and the main pipe and branch pipes are connected by flanges to achieve full-coverage purging.
Reduce equipment investment and operating energy consumption, extend catalyst life, prevent clogging, improve denitrification efficiency, and simplify cleaning operations.
Smart Images
Figure CN122230526A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the technical field of flue gas purification, and in particular to an energy-saving and anti-clogging catalyst purging device and method. Background Technology
[0002] Currently, more and more industries are using catalysts for flue gas denitrification, including power, cement, and steel industries. Due to the high dust content in flue gas, the denitrification catalyst layer is easily clogged with ash if no measures are taken, leading to catalyst deactivation and reduced denitrification efficiency. To prevent catalyst ash accumulation and blockage and improve denitrification efficiency, soot blowers are often installed in existing denitrification technologies. These blowers are installed on the top of the denitrification catalyst in the reactor and generally use superheated steam, compressed air, or nitrogen as the purging medium to remove ash from the catalyst surface, thereby preventing catalyst blockage. The performance of the soot blower plays a crucial role in the operation of the system.
[0003] In existing technologies, the air source for soot blowers is usually steam, compressed air, or nitrogen. However, for the steel industry, steam is often unavailable. When using compressed air or nitrogen, higher pressures (0.8-1.0 MPa) are required, necessitating significant investment in new air compressors and resulting in high operating costs. Furthermore, to ensure adequate catalyst coverage and reduce scouring and wear from the high-pressure, high-speed airflow, the nozzle orifice is typically 200-250 mm above the catalyst surface, with a distance of 60-65 mm between nozzles. However, in practice, the cleaning area often fails to cover the entire catalyst surface, leading to blockage of some catalyst pores. Additionally, the pipes used for cleaning are mostly carbon steel, which accumulates rust over time. The small nozzle diameter makes them prone to clogging, significantly reducing the soot blower's cleaning efficiency. This leads to widespread catalyst buildup, increased differential pressure in the catalyst layer, increased system energy consumption, decreased catalyst performance, and even catalyst failure. Summary of the Invention
[0004] The purpose of this invention is to solve the problems in the prior art by proposing an energy-saving and anti-clogging catalyst purging device and method that can solve the above problems.
[0005] To achieve the above objectives, this invention proposes an energy-saving and anti-clogging catalyst purging device, comprising a medium conveying fan, a medium conveying pipeline, a heater, a soot blower, a reactor, and a catalyst. The catalyst is installed in the reactor. The conveying pipeline is equipped with a heater. The input end of the medium conveying pipeline is connected to the medium conveying fan. The input end of the soot blower is connected to the output end of the medium conveying pipeline. The soot blower includes a main pipe and several branch pipes. Several branch pipes are connected to the main pipe. The branch pipes are arranged above the catalyst. Several Venturi nozzles are installed on the lower end face of the branch pipes.
[0006] Preferably, the distance L between adjacent Venturi nozzles matches the hole spacing of the lower catalyst, with L being between 7 mm and 12 mm, and the height H of the Venturi nozzle outlet from the upper surface of the catalyst being between 30 mm and 50 mm.
[0007] Preferably, the medium conveying blower is a low-pressure Roots blower with a pressure of 120kPa~150kPa.
[0008] Preferably, the main pipe is a circular pipe and the branch pipe is a square pipe.
[0009] Preferably, the bottom of the main pipe is connected to a first short pipe, the first short pipe is provided with a first flange, the top of the branch pipe is connected to a horseshoe-shaped joint that is smaller at the top and larger at the bottom, the horseshoe-shaped joint is connected to a second short pipe, the second short pipe is provided with a second flange, and the first flange and the second flange are fixedly installed.
[0010] Preferably, the venturi nozzle has a nozzle throat, and a feed channel and a discharge channel are respectively connected to both sides of the nozzle throat. The inner diameter of the feed channel and the discharge channel is larger than the inner diameter of the nozzle throat.
[0011] Preferably, the feed end of the venturi nozzle is equipped with a filter tube, the top opening of the filter tube away from the venturi nozzle is closed by a top plate, the filter tube is provided with a filter channel, the filter channel is connected to the feed channel, and the outer circumference of the filter tube is provided with a plurality of filter slots, the filter slots are connected to the filter channel, and the width of the filter slots is smaller than the diameter of the nozzle throat.
[0012] Preferably, the total open area of the filter slot is greater than the cross-sectional area of the nozzle throat.
[0013] Preferably, the nozzle throat diameter is 1.5mm to 2.0mm.
[0014] Preferably, the main pipe and branch pipe are installed horizontally, the venturi nozzle is installed vertically, the top of the venturi nozzle protrudes from the inner bottom surface of the branch pipe, and both ends of the branch pipe are provided with drain pipes, the ends of which are provided with removable caps.
[0015] Preferably, the heater is a gas-to-gas heat exchanger, which is installed inside the reactor, with the catalyst located above the gas-to-gas heat exchanger.
[0016] This invention also proposes an energy-saving and anti-clogging catalyst purging method, which is implemented by the aforementioned energy-saving and anti-clogging catalyst purging device, including the following steps: the soot blowing medium is sent into the medium conveying pipeline by the medium conveying fan, the soot blowing medium in the medium conveying pipeline flows through the heater, the temperature rises, the operating volume flow rate increases, the heated soot blowing medium enters the soot blower, the purging medium enters the branch pipe through the main pipe, then enters the Venturi nozzle through the filter slot, and finally sprays onto the ash accumulation surface. Large particles of impurities are intercepted by the filter slot and fall to the bottom of the branch pipe.
[0017] The beneficial effects of this invention are: This invention uses low-pressure air as the medium to replace high-pressure steam or compressed air, and selects a lower-energy-consumption Roots blower to replace a high-energy-consumption air compressor for medium transportation. This can reduce equipment investment and operating energy consumption, which is beneficial to system energy saving. At the same time, it also reduces the scouring and wear of the catalyst by the high-pressure airflow and extends the service life of the catalyst. This invention adds a gas-gas heater to the medium pipeline and places the heater at the lower end of the catalyst in the reactor. High-temperature flue gas is used as the purging medium to heat the medium to 200°C~300°C. As the temperature of the medium in the pipe increases, the volumetric flow rate increases. While ensuring the amount of gas used for nozzle purging, the inlet air volume of the medium conveying fan can be reduced, thus reducing the power consumption of the fan. At the same time, when the high-temperature purging medium comes into contact with the catalyst, the thermal stress can be reduced, thus ensuring the structural strength of the catalyst surface. The main pipe and branch pipes of the sootblower are connected by flanges, which facilitates subsequent equipment maintenance and replacement. The spacing between each Venturi nozzle in this invention is the same as or similar to the spacing between the catalyst orifices, which is beneficial for achieving precise hole-to-hole purging between the nozzle and the catalyst orifice. At the same time, it reduces the distance between the Venturi nozzle outlet and the upper surface of the catalyst. By setting the height H to 30mm to 50mm, the gas purging intensity of the low-pressure blower can also meet the catalyst cleaning requirements, effectively preventing catalyst blockage. It is especially suitable for purging SCR denitrification catalysts in cement kiln flue gas. The present invention has a filter tube installed at the top of the nozzle, which can effectively block impurities larger than the diameter of the nozzle throat from entering the nozzle and prevent the nozzle from clogging. Compared with the prior art, it can greatly improve the performance of the soot blower and is more conducive to the long-term stable operation of the system. Impurities intercepted on the filter tube can automatically fall to the bottom of the branch pipe and flow and converge towards both ends of the branch pipe under the influence of the airflow inside the branch pipe. After the equipment is stopped, the plug can be opened and the impurities can be removed through the drain pipe. The cleaning operation is simple.
[0018] The features and advantages of the present invention will be described in detail through embodiments and in conjunction with the accompanying drawings. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the soot blower structure of the present invention; Figure 3 This is a schematic diagram of the branch pipe connection of the present invention; Figure 4 This is a schematic diagram of the interior of the venturi nozzle of the present invention; Figure 5 This is a schematic diagram of the cross-section of the filter tube of the present invention.
[0020] In the diagram: 1. Media conveying fan; 2. Media conveying pipeline; 3. Soot blower; 4. Reactor; 5. Catalyst; 6. Heater; 31. Telescopic mechanism; 32. Main pipe; 33. Branch pipe; 34. Drain pipe; 35. Plug; 36. Venturi nozzle; 37. Horseshoe joint; 361. Nozzle throat; 362. Filter pipe; 363. Filter groove; 321. First short pipe; 322. First flange; 331. Second short pipe; 332. Second flange; 364. Feed channel; 365. Discharge channel; 366. Top plate; 367. Filter channel. Detailed Implementation
[0021] See Figures 1 to 5 An energy-saving and anti-clogging catalyst purging device and method includes a medium conveying fan 1, a medium conveying pipeline 2, a heater 6, a rake soot blower 3, a reactor 4, and a catalyst 5. The catalyst 5 is installed in the reactor 4. The heater 6 is provided on the conveying pipeline. The input end of the medium conveying pipeline 2 is connected to the medium conveying fan 1. The input end of the rake soot blower 3 is connected to the output end of the medium conveying pipeline 2. The rake soot blower 3 includes a main pipe 32 and several branch pipes 33. Several branch pipes 33 are arranged on the main pipe 32 and are arranged above the catalyst 5. Several Venturi nozzles 36 are vertically installed on the center line of the lower end face of the branch pipes 33.
[0022] The distance L between adjacent Venturi nozzles 36 is matched with the hole spacing of the lower catalyst 5, and L is between 7mm and 12mm. The height H of the Venturi nozzle 36 outlet from the upper surface of the catalyst 5 is 30mm to 50mm.
[0023] The aforementioned medium conveying blower is a low-pressure Roots blower with a pressure of 120kPa~150kPa.
[0024] The main pipe 32 is a circular pipe, and the branch pipe 33 is a square pipe.
[0025] The bottom of the main pipe 32 is connected to a first short pipe 321, and the first short pipe 321 is provided with a first flange 322. The top of the branch pipe 33 is connected to a horseshoe-shaped joint 37 that is smaller at the top and larger at the bottom. The horseshoe-shaped joint 37 is connected to a second short pipe 331, and the second short pipe 331 is provided with a second flange 332. The first flange 322 and the second flange 332 are fixedly installed.
[0026] The venturi nozzle 36 has a nozzle throat 361 inside. The nozzle throat 361 is connected to a feed channel 364 and a discharge channel 365 on both sides. The inner diameter of the feed channel 364 and the discharge channel 365 is larger than the inner diameter of the nozzle throat 361.
[0027] A filter tube 362 is installed at the feed end of the Venturi nozzle 36. The top opening of the filter tube 362 away from the Venturi nozzle 36 is closed by a top plate 366. A filter channel 367 is provided inside the filter tube 362, which is connected to the feed channel 364. A plurality of filter slots 363 are provided around the outer periphery of the filter tube 362. The filter slots 363 are connected to the filter channel 367. The width of the filter slots 363 is smaller than the diameter of the nozzle throat 361.
[0028] The small diameter setting of the nozzle throat 361 can enhance the airflow velocity at the nozzle and improve the purging effect.
[0029] The total opening area of the filter slot 363 is greater than the cross-sectional area of the nozzle throat 361.
[0030] The nozzle throat diameter is 1.5mm~2.0mm.
[0031] The filter slot 361 can effectively block particles larger than the nozzle throat 361 outside the filter slot 363, preventing large particles of impurities from entering the nozzle throat 361 and clogging the nozzle 36. At the same time, the gas flow area of the filter slot 363 is larger than the flow cross-section of the nozzle throat 361, ensuring the medium flow of the nozzle 36 and ensuring the purging effect of the nozzle 36.
[0032] The main pipe 32 and branch pipe 33 are both installed horizontally, the venturi nozzle 36 is installed vertically, and the top of the venturi nozzle 36 protrudes from the inner bottom surface of the branch pipe 33; the filter pipe is connected to the top of the venturi nozzle 36, and the two ends of the branch pipe 33 are provided with drain pipes 34, and the end of the drain pipe 34 is provided with a removable cap 35.
[0033] The heater 6 is a gas-to-gas heat exchanger, which is installed inside the reactor 4, and the catalyst 5 is located above the gas-to-gas heat exchanger.
[0034] The gas-to-gas heat exchanger is a tubular heater, consisting of multiple carbon steel tubes arranged in parallel, with an outer diameter of ø38~ø45. The purging medium flows inside the tubes, while the high-temperature flue gas flows outside the tubes.
[0035] This invention also proposes an energy-saving and anti-clogging catalyst purging method, which is implemented by the energy-saving and anti-clogging catalyst purging device, including the following steps: the blowing medium is sent into the medium conveying pipeline 2 by the medium conveying fan 1. After the blowing medium in the medium conveying pipeline 2 flows through the heater 6, the temperature rises and the operating volume flow rate increases. The heated blowing medium enters the rake blower 3. The purging medium enters the branch pipe 33 through the main pipe 32, and then enters the Venturi nozzle 36 through the filter slot 363. Finally, it is sprayed onto the ash accumulation surface. Large particles of impurities are intercepted by the filter slot 363 and fall to the bottom of the branch pipe 33.
[0036] The main pipe 32 and branch pipe 33 of the soot blower 3, under the action of the telescopic mechanism 31, blow back and forth to fully cover the surface of the catalyst 5, ensuring the effective reaction area of the catalyst 5 and improving the denitrification efficiency.
[0037] The air inlet of branch pipe 33 is located in the middle. The airflow inside the branch pipe will flow to both ends. The intercepted impurities will gradually gather at both ends of the branch pipe under the action of the airflow. After the equipment stops, the plug cap can be opened to remove the impurities from the drain pipe to complete the cleaning.
[0038] The above embodiments are illustrative of the present invention and are not intended to limit the present invention. Any simple modifications to the present invention are within the scope of protection of the present invention.
Claims
1. An energy-saving and anti-clogging catalyst purging device, characterized in that: The system includes a medium conveying fan (1), a medium conveying pipeline (2), a heater (6), a soot blower (3), a reactor (4), and a catalyst (5). The catalyst (5) is installed in the reactor (4). The conveying pipeline is equipped with a heater (6). The input end of the medium conveying pipeline (2) is connected to the medium conveying fan (1). The input end of the soot blower (3) is connected to the output end of the medium conveying pipeline (2). The soot blower (3) includes a main pipe (32) and several branch pipes (33). Several branch pipes (33) are connected to the main pipe (32). The branch pipes (33) are arranged above the catalyst (5). Several Venturi nozzles (36) are installed on the lower end face of the branch pipes (33).
2. The energy-saving and anti-clogging catalyst purging device as described in claim 1, characterized in that: The distance L between adjacent Venturi nozzles (36) matches the hole spacing of the lower catalyst (5), and the height H of the Venturi nozzle (36) outlet from the upper surface of the catalyst (5) is 30mm~50mm.
3. The energy-saving and anti-clogging catalyst purging device as described in claim 1, characterized in that: The main pipe (32) is a circular pipe, and the branch pipe (33) is a square pipe.
4. The energy-saving and anti-clogging catalyst purging device as described in claim 1, characterized in that: The bottom of the main pipe (32) is connected to a first short pipe (321), and a first flange (322) is provided on the first short pipe (321). The top of the branch pipe (33) is connected to a horseshoe-shaped connector (37) that is smaller at the top and larger at the bottom. The horseshoe-shaped connector (37) is connected to a second short pipe (331), and a second flange (332) is provided on the second short pipe (331). The first flange (322) and the second flange (332) are fixedly installed.
5. The energy-saving and anti-clogging catalyst purging device as described in claim 1, characterized in that: The Venturi nozzle (36) is provided with a nozzle throat (361). The nozzle throat (361) is connected to a feed channel (364) and a discharge channel (365) on both sides. The inner diameters of the feed channel (364) and the discharge channel (365) are both larger than the inner diameter of the nozzle throat (361).
6. The energy-saving and anti-clogging catalyst purging device as described in claim 5, characterized in that: The feed end of the Venturi nozzle (36) is equipped with a filter tube (362). The top opening of the filter tube (362) away from the Venturi nozzle (36) is closed by a top plate (366). The filter tube (362) is provided with a filter channel (367), which is connected to the feed channel (364). The outer circumference of the filter tube (362) is provided with a number of filter slots (363), which are connected to the filter channel (367). The width of the filter slots (363) is smaller than the diameter of the nozzle throat (361).
7. The energy-saving and anti-clogging catalyst purging device as described in claim 6, characterized in that: The total opening area of the filter slot (363) is greater than the cross-sectional area of the nozzle throat (361).
8. The energy-saving and anti-clogging catalyst purging device as described in claim 6, characterized in that: The main pipe (32) and branch pipe (33) are both installed horizontally, the Venturi nozzle (36) is installed vertically, the top of the Venturi nozzle (36) protrudes from the inner bottom surface of the branch pipe (33), and the two ends of the branch pipe (33) are provided with drain pipes (34), and the end of the drain pipe (34) is provided with a detachable cap (35).
9. The energy-saving and anti-clogging catalyst purging device as described in claim 1, characterized in that: The heater (6) is a gas-to-gas heat exchanger, which is installed inside the reactor (4), and the catalyst (5) is located above the gas-to-gas heat exchanger.
10. An energy-saving and anti-clogging catalyst purging method, characterized in that: The energy-saving and anti-clogging catalyst purging device as described in any one of claims 1 to 9 is implemented by the following steps: the purging medium is sent into the medium conveying pipeline (2) by the medium conveying fan (1), the purging medium in the medium conveying pipeline (2) flows through the heater (6) and the temperature rises, the working volume flow rate increases, the heated purging medium enters the purging blower (3), the purging medium enters the branch pipe (33) through the main pipe (32), and then enters the Venturi nozzle (36) through the filter slot (363), and finally sprays onto the ash accumulation surface. Large particles of impurities are intercepted by the filter slot (363) and fall to the bottom of the branch pipe (33).