A flare gas treatment system

Abstract

The present application provides a kind of flare gas processing system, including direct-fired exhaust gas treatment equipment, waste heat boiler, desulfurization tower and chimney in turn communication;Direct-fired exhaust gas treatment equipment before being passed into flare gas, bore temperature is 760-1000 ℃;Waste heat boiler is provided with SNCR ammonia water nozzle and SCR catalyst.High temperature flue gas after oxidation decomposition is transported to waste heat boiler, and high temperature or saturated steam is generated by waste heat recovery, while nitrogen oxides generated after flare gas combustion are treated by SNCR ammonia water nozzle and SCR catalyst using redox reaction;High temperature flue gas after denitrification is transported to desulfurization tower for desulfurization treatment, and flue gas after desulfurization is discharged by chimney.The present application carries out denitrification and desulfurization treatment to flare gas, reduces pollutants in emission gas, and solves environmental pollution caused by direct combustion of flare gas.

Description

Technical Field

[0001] This invention relates to the field of waste gas treatment technology, and specifically to a flare gas treatment system. Background Technology

[0002] During the production of chemical products, emissions are inevitable due to heating and pressurization, process adjustment, equipment switching, pressure relief by safety valves and pressure valves, as well as start-up, shutdown, and abnormal operating conditions. The emissions are flare gases, which mainly contain carbon atoms, hydrogen and hydrocarbons, as well as flammable, explosive, toxic and harmful substances such as sulfides and nitrogen-containing organic matter. Moreover, the emission time is intermittent and fluctuates.

[0003] Currently, flare gas is mainly treated by incineration using flares. However, the incineration system not only requires continuous combustion of the flare gas, resulting in fuel waste, but also suffers from incomplete combustion. When combustion is incomplete, pollutants such as sulfides and nitrogen oxides are emitted into the environment, causing negative impacts. Summary of the Invention

[0004] The purpose of this invention is to provide a flare gas treatment system, and the technical problem to be solved is the environmental pollution caused by the direct combustion of flare gas.

[0005] This invention is achieved through the following technical solution: A flare gas treatment system includes a direct-fired waste gas treatment device, a waste heat boiler, a desulfurization tower, and a chimney connected in sequence. Before the flare gas is introduced, the internal temperature of the above-mentioned direct-fired exhaust gas treatment equipment is 760-1000℃. The aforementioned waste heat boiler is equipped with SNCR ammonia water nozzles and SCR catalysts.

[0006] Furthermore, it also includes a pressure buffer device, which is connected to the air inlet of the direct-fired exhaust gas treatment equipment; the pressure buffer device is used to buffer the pressure of the flare gas input into the direct-fired exhaust gas treatment equipment.

[0007] Furthermore, the aforementioned pressure buffer equipment includes an inlet water seal tank, an outlet water seal tank, and a wet gas holder; The outlet of the aforementioned inlet water seal tank and the inlet of the wet gas holder are connected by a first pipe; the outlet of the aforementioned wet gas holder and the inlet of the outlet water seal tank are connected by a second pipe. The outlet of the aforementioned water seal tank and the inlet of the direct-fired waste gas treatment equipment are connected by a third pipeline.

[0008] Furthermore, the air inlet of the aforementioned inlet water seal tank is provided with a fourth pipe, which is inserted into the air inlet of the inlet water seal tank and extends towards the bottom of the inlet water seal tank; the air outlet of the aforementioned inlet water seal tank is located at the top of the inlet water seal tank. The aforementioned second pipe is inserted into the air inlet of the outlet water seal tank and extends towards the bottom of the outlet water seal tank; the air outlet of the aforementioned outlet water seal tank is located at the top of the outlet water seal tank.

[0009] Furthermore, the aforementioned direct-fired waste gas treatment equipment includes an oxidation decomposition furnace and a burner, with the burner located below the oxidation decomposition furnace, and a thermocouple assembly installed inside the oxidation decomposition furnace.

[0010] Furthermore, the aforementioned wet gas holder includes a bottom cabinet, a middle cabinet, a top cabinet, and a support frame. The middle cabinet is housed within the bottom cabinet, and the top cabinet is housed within the middle cabinet. The bottom cabinet contains liquid, and the inlet and outlet of the wet gas holder are located within the bottom cabinet. The aforementioned support is equipped with guide rails, and the aforementioned middle cabinet and top cabinet are equipped with guide wheels that are compatible with the guide rails; when the gas pressure of the aforementioned wet gas holder increases, it pushes the aforementioned top cabinet or middle cabinet to move upward along the guide rails.

[0011] Furthermore, the aforementioned second pipeline is equipped with a first induced draft fan.

[0012] Furthermore, the aforementioned waste heat boiler and desulfurization tower are connected via a fifth pipeline; the aforementioned fifth pipeline is equipped with a second induced draft fan.

[0013] Furthermore, a flue gas monitoring device is installed inside the aforementioned chimney.

[0014] Compared with the prior art, the present invention has the following advantages and beneficial effects: The flare gas is transported to the aforementioned direct-fired waste gas treatment equipment for oxidation and decomposition. The high-temperature flue gas after oxidation and decomposition is then transported to the aforementioned waste heat boiler for waste heat recovery to generate high-temperature or saturated steam. Simultaneously, nitrogen oxides generated after flare gas combustion are treated by oxidation-reduction reactions using SNCR ammonia water nozzles and SCR catalysts. The denitrified high-temperature flue gas is then transported to a desulfurization tower for desulfurization treatment, and the desulfurized flue gas is discharged through a chimney. This invention denitrifies and desulfurizes flare gas, reducing pollutants in the emitted gas and solving the environmental pollution caused by the direct combustion of flare gas. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings: Figure 1 This is a block diagram showing the overall connection of the flare gas treatment system. Figure 2A schematic diagram of the process equipment and instrument connections for conveying flare gas; Figure 3 A schematic diagram of the process equipment and instrument connections for combustion, waste heat recovery, desulfurization, denitrification, and emissions; Figure 4 This is a simplified diagram of a wet gas holder.

[0016] The attached diagram shows the markings and corresponding component names: 1. Inlet water seal tank; 111. First gas concentration detector; 1112. First pressure remote transmitter A; 113. First pressure remote transmitter B; 114. First temperature remote transmitter; 115. First shut-off valve; 116. Exhaust valve; 2. Wet gas holder; 211. Second pressure remote transmitter; 212. Second temperature remote transmitter; 213. First regulating valve; 214. Third pressure remote transmitter; 215. Third temperature remote transmitter; 216. Second regulating valve; 221. Bottom cabinet; 222. Middle cabinet; 223. Top cabinet; 224. Guide rail; 225. Guide wheel; 3. Outlet water seal tank; 4. First induced draft fan; 5. Direct-fired waste gas treatment equipment; 511. Fourth pressure... 512. Remote temperature meter; 513. Remote flow meter; 514. Second shut-off valve; 515. Third regulating valve; 516. First thermocouple; 517. Second thermocouple; 518. Third thermocouple; 519. Oxygen concentration analyzer; 6. Waste heat boiler; 611. Fifth pressure meter; 612. Fifth temperature meter; 613. SNCR ammonia spray nozzle; 614. SCR catalyst; 7. Second induced draft fan; 8. Desulfurization tower; 9. Chimney; 91. Flue gas monitoring device; 11. First pipeline; 12. Second pipeline; 13. Third pipeline; 14. Fourth pipeline; 15. Fifth pipeline; 16. Sixth pipeline; 17. Seventh pipeline. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0018] First embodiment: A flare gas treatment system, combined with Figure 1 The equipment includes a direct-fired waste gas treatment device 5, a waste heat boiler 6, a desulfurization tower 8, and a chimney 9 connected in sequence. The direct-fired waste gas treatment device 5 is not limited to combustion and destruction equipment such as direct-fired oxidation reactor (TO furnace), regenerative oxidation reactor, and catalytic oxidation reactor. The waste heat boiler 6 is not limited to heat exchanger equipment such as waste heat steam boiler, hot water heat exchanger, steam waste heat boiler 6, and thermal oil boiler. Before the flare gas is introduced, the temperature inside the furnace of the above-mentioned direct-fired waste gas treatment equipment 5 is 760-1100℃ to ensure that the flare gas is completely oxidized and decomposed. An SNCR ammonia water nozzle 613 is installed at the air inlet of the aforementioned waste heat boiler 6 for ammonia-based denitrification, and an SCR catalyst 614 is installed inside the waste heat boiler 6 for the oxidation and reduction of corresponding nitrogen oxides. Furthermore, an economizer and an air preheater can be installed at the air outlet of the waste heat boiler 6 to reduce the flue gas temperature and improve the thermal utilization rate of the flue gas. The saturated or superheated steam generated by the aforementioned waste heat boiler 6 can be used for production, sales, and other economic purposes.

[0019] The flare gas is transported to the aforementioned direct-fired waste gas treatment equipment 5 for oxidation and decomposition. The high-temperature flue gas after oxidation and decomposition is then transported to the aforementioned waste heat boiler 6 for waste heat recovery to generate high-temperature or saturated steam. Simultaneously, nitrogen oxides generated after flare gas combustion are treated by oxidation-reduction reaction through SNCR ammonia water nozzles 613 and SCR catalyst 614. The denitrified high-temperature flue gas is then transported to desulfurization tower 8 for desulfurization treatment, and the desulfurized flue gas is discharged through chimney 9. This invention performs denitrification and desulfurization treatment on flare gas, reducing pollutants in the emission gas and solving the environmental pollution caused by the direct combustion of flare gas.

[0020] Second embodiment: Based on the first embodiment, a pressure buffer device is also included, which is connected to the air inlet of the direct-fired exhaust gas treatment device 5; the pressure buffer device is used to buffer the pressure of the flare gas input into the direct-fired exhaust gas treatment device 5.

[0021] Specific implementation examples, combined with Figure 1 and Figure 2 The aforementioned air pressure buffer equipment includes an inlet water seal tank 1, an outlet water seal tank 3, and a wet gas holder 2; The outlet of the aforementioned inlet water seal tank 1 and the inlet of the wet gas holder 2 are connected through a first pipe 11; the outlet of the aforementioned wet gas holder 2 and the inlet of the aforementioned outlet water seal tank 3 are connected through a second pipe 12; the aforementioned second pipe 12 is equipped with a first induced draft fan 4.

[0022] The outlet of the aforementioned water seal tank 3 and the inlet of the direct-fired waste gas treatment equipment 5 are connected through a third pipe 13.

[0023] The aforementioned waste heat boiler 6 and desulfurization tower 8 are connected through the fifth pipe 15, the aforementioned direct-fired waste gas treatment and waste heat boiler 6 are connected through the sixth pipe 16, and the aforementioned desulfurization tower 8 and chimney 9 are connected through the seventh pipe 17; the aforementioned fifth pipe 15 is equipped with a second induced draft fan 7.

[0024] The aforementioned chimney 9 is equipped with a flue gas monitoring device 91. This device 91 can be an online gas monitoring system (model SKA / NE-8100A) or a split-type design including: a non-methane total hydrocarbon concentration detector (model VOCs-800P or ZR-7220); a nitrogen oxide concentration detector (model NGP5-NOX-A); a sulfide concentration detector (model HCK600-A-H2S); and a particulate matter concentration detector (model LY-DUST400). These devices are used to monitor the concentrations of non-methane total hydrocarbons, nitrogen oxides, sulfides, and particulate matter, respectively.

[0025] The flare gas enters the wet gas holder 2 through the aforementioned inlet water seal tank 1, then enters the outlet water seal tank 3 through the aforementioned wet gas holder 2, and is then sent to the direct-fired waste gas treatment equipment 5 by the first induced draft fan 4 for incineration. After incineration, a large amount of high-temperature flue gas of about 1100°C is generated. This high-temperature flue gas is sent to the waste heat boiler 6, where it is discharged after generating superheated or saturated steam. Since the flare gas contains elements such as nitrogen and sulfur, nitrogen oxides and sulfides will be produced after combustion. Therefore, an SNCR ammonia water nozzle 613 is installed at the inlet of the aforementioned waste heat boiler 6, and an SCR catalyst 614 is installed at the outlet of the aforementioned waste heat boiler 6 for ammonia denitrification treatment. A second induced draft fan 7 is added at the rear end of the aforementioned waste heat boiler 6 to send the flue gas at the outlet of the aforementioned waste heat boiler 6 to the desulfurization tower 8 for desulfurization treatment, and then it is discharged along the chimney 9 in compliance with standards. A flue gas monitoring device 91 is installed at the chimney 9 to monitor the concentration of non-methane total hydrocarbons, nitrogen oxides, sulfides and particulate matter to ensure compliance with current environmental protection standards.

[0026] The aforementioned first induced draft fan 4 ensures that the flare gas overcomes the resistance generated by the inlet water seal tank 1, wet gas holder 2, outlet water seal tank 3, and the pipes and fittings at the front end of the first induced draft fan 4. The aforementioned first induced draft fan 4 can be configured with two operating fans and one standby fan, or one operating fan and one standby fan. Each first induced draft fan 4 requires on / off valves before and after it; pneumatic on / off valves are preferred for higher safety. A centrifugal fan with appropriate total pressure and air volume is selected based on the system pressure to deliver the flare gas to the direct-fired waste gas treatment equipment 5.

[0027] The first induced draft fan 4 and the second induced draft fan 7 are centrifugal fans, with one serving as a backup. The inlet of the second induced draft fan 7 is connected to the outlet of the waste heat boiler 6, and the outlet of the second induced draft fan 7 is connected to the inlet of the desulfurization tower 8. The second induced draft fan 7 mainly acts as a relay, conveying the flue gas after heat exchange in the waste heat boiler 6 to the desulfurization tower 8, overcoming resistance.

[0028] Third embodiment: Based on the second embodiment, both the inlet water seal tank 1 and the outlet water seal tank 3 are provided with an air inlet, an air outlet, a water inlet, a drain outlet, and an overflow outlet; The air inlet and outlet of the aforementioned inlet water seal tank 1 and outlet water seal tank 3 are both located on the top of the tank; the aforementioned water inlet, drain outlet, and overflow outlet are located on the side wall of the tank body; the air inlet of the aforementioned inlet water seal tank 1 is provided with a fourth pipe 14, which is inserted into the air inlet of the inlet water seal tank 1. The aforementioned second pipe 12 is inserted into the air inlet of the outlet water seal tank 3.

[0029] The second pipe 12 and the fourth pipe 14 extend from the top of the tank to a depth of 500mm from the bottom. Depending on the flare gas pressure, 500mm or more of production water can be injected through the inlet. This production water can be tap water and is used to liquid seal the flare gas, preventing backfire and other phenomena. Simultaneously, to prevent excessive pressure inside the tank, a remote pressure gauge and vent are installed to ensure pressure balance within the tank. Furthermore, appropriate heat tracing and insulation can be applied to the tank according to the environment to prevent the water inside the tank from freezing during cold winter months.

[0030] In addition, combined Figure 2 and Figure 3 A branch pipe can be installed on the fourth pipe 14, and the branch pipe is equipped with an exhaust valve 116. The fourth pipe 14 is equipped with a first shut-off valve 115, a first gas concentration detector 111 (such as MIC-500S or MIC-600), a first pressure remote transmitter A1112, a first pressure remote transmitter B113 (such as model YTZ-150), and a first temperature remote transmitter 114 (such as model WTYY-1021-D). The first shut-off valve 115 and the exhaust valve 116 are interlocked. In case of an emergency at the front or rear of the flare gas, the first shut-off valve 115 can be closed and the exhaust valve 116 can be opened to release the flare gas in an emergency, ensuring system safety.

[0031] The first pipeline 11 is equipped with a second pressure remote gauge 211 (model YTZ-150), a second temperature remote gauge 212 (model WTYY-1021-D), and a first regulating valve 213. The second pipeline 12 is equipped with a third pressure remote gauge 214 (model YTZ-150), a third temperature remote gauge 215 (model WTYY-1021-D), and a second regulating valve 216. The third pipeline 13 is equipped with a fourth pressure remote gauge 511 (model YTZ-150), a fourth temperature remote gauge 512 (model WTYY-1021-D), a flow remote gauge 513 (model LWQ), a second shut-off valve 514, and a third regulating valve 515. The fifth pipeline 15 is equipped with a fifth pressure remote gauge 611 (model YTZ-150) and a fifth temperature remote gauge 612 (model WTYY-1021-D). The sixth pipeline 16 is equipped with an oxygen concentration analyzer 519 (model CI1300).

[0032] Fourth embodiment: Based on any of the above embodiments, the aforementioned wet gas holder 2 includes a bottom cabinet 221, a middle cabinet 222, a top cabinet 223, and a support frame, combined with... Figure 4 The aforementioned middle cabinet 222 is housed within the bottom cabinet 221, and the top cabinet 223 is housed within the middle cabinet 222; the aforementioned bottom cabinet 221 contains liquid, and the air inlet and outlet of the wet gas holder 2 are located in the bottom cabinet 221. The bracket is provided with a guide rail 224, and the middle cabinet 222 and the top cabinet 223 are provided with guide wheels 225 that are adapted to the guide rail 224. When the gas pressure of the wet gas holder 2 increases, it pushes the top cabinet 223 or the middle cabinet 222 to move upward along the guide rail 224.

[0033] This invention does not limit the number of intermediate cabinets 222, and wet gas holders 2 of different sizes can be designed according to different air volumes and scales. When the flow rate or pressure of the flare gas entering the wet gas holder 2 increases, the flare gas will preferentially push the upper cabinet and the guide rollers 225 on the upper cabinet to move upward along the guide rail 224, increasing the volume of the wet gas holder 2 and ensuring stable delivery of flare gas flow rate and pressure. If the flare gas flow rate and pressure continue to increase, the intermediate cabinet 222 and the guide rollers 225 on the intermediate cabinet 222 will support the upper cabinet to continue rising along the guide rail 224 until the guide rail 224 reaches its limit, which is the maximum load of the wet gas holder 2. If the flare gas flow rate or pressure decreases, the intermediate cabinet 222 and the upper cabinet will move in opposite directions. Through the movement of the upper cabinet and the intermediate cabinet 222, the internal volume of the wet gas holder 2 is increased, ensuring the pressure balance inside the wet gas holder 2, avoiding flare gas fluctuations and intermittent emissions, ensuring stable and smooth delivery of flare gas, and ensuring the load and smooth operation of the downstream processing equipment.

[0034] Meanwhile, the aforementioned bottom cabinet 221 is equipped with an air inlet, an air outlet, a water inlet, an overflow outlet, and a drain outlet. The water inlet is used to fill the bottom cabinet 221 with water, the overflow outlet is used to drain excess water from the bottom cabinet 221, and the drain outlet is used to drain water from the bottom cabinet 221 during maintenance or other situations. The aforementioned bottom cabinet 221 serves a sealing function to prevent flare gas leakage, accumulation in the surrounding environment to form an explosive atmosphere, or accidents such as poisoning or asphyxiation; and in the event of a fire, it serves to isolate the flame, ensuring the safety of system operation.

[0035] In addition, radar reflectors, light-transmitting holes, and vents can be installed on the top of the aforementioned high-level cabinets. Considering environmental factors, the aforementioned bottom cabinet 221 can be equipped with heat tracing and insulation.

[0036] Fifth embodiment: Based on any of the above embodiments, the direct-fired waste gas treatment equipment 5 includes an oxidation decomposition furnace and a burner, the burner being disposed below the oxidation decomposition furnace, and a thermocouple assembly being disposed inside the oxidation decomposition furnace.

[0037] The aforementioned oxidative decomposition furnace can be constructed from rolled and welded Q235 carbon steel, with concealed welded studs on the inner wall. Two layers of 50mm thick aluminum silicate insulation cotton are laid at staggered joints, and then cast using plastic or other castable materials (or high-temperature brick masonry). This ensures that when the internal temperature exceeds 1000℃, the external wall temperature of the oxidative decomposition furnace is less than or equal to the ambient temperature plus 20℃. Simultaneously, a first thermocouple 516, a second thermocouple 517, and a third thermocouple 518 are installed at the bottom, middle, and top of the furnace, respectively, to detect the furnace temperature and ensure sufficient oxidative decomposition of combustibles in the flare gas. A burner is installed at the bottom of the furnace; this burner can be skid-mounted, and the fuel includes, but is not limited to, natural gas and diesel. The burner ensures that the furnace interior maintains a high-temperature environment above 760℃ before the flare gas is introduced. Furthermore, the burner is equipped with a pilot flame to ensure successful random ignition and guarantee system safety.

[0038] An oxygen content analyzer is installed at the outlet of the aforementioned oxidative decomposition furnace to analyze whether the flare gas has reacted completely, ensuring that the oxygen content in the flue gas after combustion is between 6% and 8%, thus guaranteeing the full oxidative decomposition of the flare gas.

[0039] Sixth embodiment: Based on any of the above embodiments, the SNCR ammonia water nozzle 613 of the waste heat boiler 6 is equipped with an ammonia water skid. The ammonia water skid generally includes an ammonia water tank. The ammonia water can be transported by an ammonia water pipeline network or can be manually prepared and poured into the ammonia water tank. Then, an ammonia water pump sprays the ammonia water into the pipeline of the waste heat boiler 6 through the SNCR ammonia water nozzle 613 installed at the air inlet of the waste heat boiler 6. At a high temperature of 950℃~1050℃, the ammonia water reacts with the nitrogen oxides in the high-temperature flue gas after combustion and decomposition by the direct-fired waste gas treatment equipment 5 to generate nitrogen, carbon dioxide and water, thereby reducing the nitrogen oxides in the high-temperature flue gas.

[0040] The aforementioned SNCR ammonia spray nozzle 613 is generally affected by the flue gas velocity, temperature distribution, and NOx distribution within the waste heat boiler 6 flue, resulting in a typical treatment efficiency of 30%–50%. Therefore, an SCR catalyst 614 is used at the downstream end of the waste heat boiler 6 for further denitrification. Sufficient amounts of the SCR catalyst 614 (mainly composed of TiO2, V2O5, and WO3) are added to the upstream end of the economizer (at approximately 300°C). At 300°C, it undergoes a redox reaction with nitrogen oxides in the high-temperature flue gas to produce nitrogen and water.

[0041] The aforementioned waste heat boiler's 6SNCR and SCR two-stage redox reactions can treat the nitrogen oxides produced after flare gas combustion.

[0042] Seventh embodiment: Based on any of the above embodiments, the height of the chimney 9 is greater than or equal to 15m and 3m higher than the tallest surrounding building. Before emitting flue gas, emission indicators are tested.

[0043] The workflow of the flare gas treatment system is as follows: The flue gas monitoring device 91 is installed 100 meters away from the first shut-off valve 115. It ensures that after the gas concentration, pressure and temperature detected by the first gas concentration detector 111, the first pressure remote transmitter A1112, the first pressure remote transmitter B113 and the first temperature remote transmitter 114 exceed the set values, the time taken for the flare gas to flow through the 100-meter pipeline is greater than the closing time of the first shut-off valve 115, thereby ensuring system safety.

[0044] The aforementioned second pressure remote gauge 211 and second temperature remote gauge 212 detect the flare gas entering the wet gas holder 2, and simultaneously work with the first regulating valve 213 to control the flow of the flare gas. At the rear end of the wet gas holder 2, the pressure fluctuation of the flare gas is measured by the third pressure remote gauge 214 and the third temperature remote gauge 215, and the flare gas flow rate is adjusted by the second regulating valve 216.

[0045] The fourth pressure remote gauge 511, the fourth temperature remote gauge 512, and the flow remote gauge 513 monitor the flare gas entering the direct-fired waste gas treatment equipment 5. The second shut-off valve 514 and the third regulating valve 515 control the on / off state and flow rate of the flare gas. The fifth pressure remote gauge 611 and the fifth temperature remote gauge 612 detect the pressure and temperature at the outlet of the waste heat boiler 6. The pressure can be interlocked with the second induced draft fan 7, which is a variable frequency fan and can adjust its frequency according to the pressure of the fifth pressure remote gauge 611. The fifth temperature remote gauge 612 can monitor the outlet temperature of the waste heat boiler 6 to verify the waste heat utilization rate.

[0046] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A flare gas treatment system, characterized in that, It includes a direct-fired exhaust gas treatment device (5), a waste heat boiler (6), a desulfurization tower (8), and a chimney (9) connected in sequence; Before the flare gas is introduced, the temperature inside the direct-fired exhaust gas treatment equipment (5) is 760-1000℃. The waste heat boiler (6) is equipped with an SNCR ammonia water nozzle (613) and an SCR catalyst (614).

2. The flare gas treatment system according to claim 1, characterized in that, It also includes a pressure buffer device, which is connected to the air inlet of the direct-fired exhaust gas treatment device (5); the pressure buffer device is used to buffer the pressure of the flare gas input into the direct-fired exhaust gas treatment device (5).

3. The flare gas treatment system according to claim 2, characterized in that, The pressure buffer device includes an inlet water seal tank (1), an outlet water seal tank (3), and a wet gas holder (2); The outlet of the inlet water seal tank (1) and the inlet of the wet gas holder (2) are connected by a first pipe (11); the outlet of the wet gas holder (2) and the inlet of the outlet water seal tank (3) are connected by a second pipe (12). The outlet of the outlet water seal tank (3) and the inlet of the direct-fired waste gas treatment equipment (5) are connected by a third pipe (13).

4. The flare gas treatment system according to claim 3, characterized in that, The inlet of the inlet water seal tank (1) is provided with a fourth pipe (14), which is inserted into the inlet of the inlet water seal tank (1) and extends to the bottom of the inlet water seal tank (1); the outlet of the inlet water seal tank (1) is provided at the top of the inlet water seal tank (1); The second pipe (12) is inserted into the air inlet of the outlet water seal tank (3) and extends to the bottom of the outlet water seal tank (3); the air outlet of the outlet water seal tank (3) is located at the top of the outlet water seal tank (3).

5. The flare gas treatment system according to claim 1, characterized in that, The direct-fired waste gas treatment equipment (5) includes an oxidation decomposition furnace and a burner. The burner is located below the oxidation decomposition furnace, and a thermocouple assembly is installed inside the oxidation decomposition furnace.

6. The flare gas treatment system according to claim 3, characterized in that, The wet gas holder (2) includes a bottom cabinet (221), a middle cabinet (222), a top cabinet (223), and a support frame. The middle cabinet (222) is fitted inside the bottom cabinet (221), and the top cabinet (223) is fitted inside the middle cabinet (222). The bottom cabinet (221) contains liquid, and the air inlet and outlet of the wet gas holder (2) are located in the bottom cabinet (221). The support is provided with a guide rail (224), and the middle cabinet (222) and the top cabinet (223) are provided with guide wheels (225) adapted to the guide rail (224); when the gas pressure of the wet gas holder (2) increases, it pushes the top cabinet (223) or the middle cabinet (222) to move upward along the guide rail (224).

7. The flare gas treatment system according to claim 3, characterized in that, The second pipe (12) is equipped with a first induced draft fan (4).

8. The flare gas treatment system according to claim 1, characterized in that, The waste heat boiler (6) and the desulfurization tower (8) are connected by a fifth pipe (15); the fifth pipe (15) is equipped with a second induced draft fan (7).

9. The flare gas treatment system according to claim 1, characterized in that, A flue gas monitoring device (91) is installed inside the chimney (9).

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