Flameless oxidation flue gas recycling system for low-concentration gas and air exhaust gas in coal mine

Abstract

The present application belongs to the technical field of flue gas recycling, in particular to a coal mine low-concentration gas and air exhaust gas flameless oxidation flue gas recycling system, aiming at the problem of high gas dust content in the existing coal mine low-concentration gas and air exhaust gas utilization system, the following scheme is proposed, including a low-concentration gas conveying pipe. The coal mine low-concentration gas and air exhaust gas flameless oxidation flue gas recycling system disclosed by the present application replaces part of air with part of exhaust gas as primary and secondary mixed gas, thereby increasing the gas temperature entering the RTO flameless heat accumulation oxidation device, increasing the high-temperature flue gas amount in the waste heat boiler, increasing the high-temperature and high-pressure steam output in the waste heat boiler, reducing the exhaust gas temperature of the waste heat boiler, increasing the feed water preheater behind the economizer, increasing the inlet water temperature entering the economizer, reducing the final exhaust gas temperature, improving the waste heat utilization rate, and thereby improving the power generation capacity or heat supply capacity or cogeneration output, while increasing the carbon emission reduction amount.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of flue gas recycling, in particular to a coal mine low-concentration gas and air exhaust gas flameless oxidation flue gas recycling system. BACKGROUND

[0002] In the coal mine low-concentration gas and air exhaust gas flameless oxidation comprehensive utilization system, the coal mine low-concentration gas and air exhaust gas are mixed and diluted and then subjected to flameless oxidation in the RTO, thereby generating a large amount of heat. The high-temperature flue gas of the RTO passes through a waste heat boiler to generate high-temperature and high-pressure steam, and the high-temperature and high-pressure steam passes through a condensing steam turbine to generate electricity or passes through a steam-water heat exchanger to generate hot water for heating or bathing.

[0003] The coal mine gas contains a large amount of dust, and static electricity is generated during transportation, which may cause an explosion and result in a serious accident. In addition, the high content of gas dust may block the heat storage body of the RTO, thereby increasing the resistance and energy consumption and even causing production to be stopped. SUMMARY

[0004] The present application discloses a coal mine low-concentration gas and air exhaust gas flameless oxidation flue gas recycling system, which aims to solve the technical problem of high content of gas dust in the existing coal mine low-concentration gas and air exhaust gas utilization system.

[0005] The coal mine low-concentration gas and air exhaust gas flameless oxidation flue gas recycling system comprises:

[0006] A low-concentration gas conveying pipe is provided with a three-proofing device, and is connected with a first mixing device.

[0007] An air conveying pipe one is connected with the first mixing device, and the first mixing device is connected with a first mixed gas pipe.

[0008] An air conveying pipe two is connected with a second mixing device, the second mixing device is connected with a second mixed gas pipe, the second mixed gas pipe is connected with an RTO air blower, and the RTO air blower is connected with an RTO flameless heat storage oxidation device.

[0009] The flue gas return pipe is connected with the bottom flue gas pipe, and the flue gas return pipe is connected with the second flue gas exhaust pipe and the flue gas exhaust pipe, the second flue gas exhaust pipe is connected with the second air conveying pipe, the flue gas exhaust pipe is connected with the first air conveying pipe, and the low-concentration gas conveying pipe is provided with the particulate matter treatment device; the second-stage mixed gas pipe is provided with the second methane concentration detector and the second temperature detector, the top flue gas pipe is provided with the waste heat boiler, the waste heat boiler is connected with the high-pressure steam pipe, the high-pressure steam pipe is connected with the steam-water heat exchanger and the condensing steam turbine, the condensing steam turbine is connected with the generator, the waste heat flue gas pipe is provided with the economizer, the third temperature detector, the feedwater preheater and the fourth temperature detector, and the bottom flue gas pipe is provided with the oxygen analyzer and the fifth temperature detector, the first-stage mixed gas pipe is provided with the first methane concentration detector and the first temperature detector, and the first-stage mixed gas pipe is connected with the second-stage mixer, the RTO flameless heat accumulation oxidation device is provided with the top flue gas pipe and the bottom flue gas pipe, the top flue gas pipe is connected with the waste heat flue gas pipe, the waste heat flue gas pipe is connected with the bottom flue gas pipe, the bottom flue gas pipe is connected with the flue gas exhaust pipe, and the flue gas return pipe is provided with the return fan.

[0010] In a preferred scheme, the particulate matter treatment device comprises a treatment tube arranged on the low-concentration gas conveying pipe, the treatment tube is externally provided with a cutting groove, the inner wall of the cutting groove is fixedly connected with a mounting plate, the inner wall of the treatment tube is fixedly connected with three equidistantly distributed fixed frames, the inner walls of the three fixed frames are respectively fixedly connected with a coarse-hole filter screen, an electrostatic dust removal screen and a HEPA filter screen, and the treatment tube is internally provided with a particulate matter cleaning module, and the mounting plate is internally provided with a quick replacement module; the particulate matter cleaning module comprises two linear motors, the two linear motors are respectively located on the sides of the coarse-hole filter screen and the electrostatic dust removal screen away from the bottom flue gas pipe, the outer sides of the linear motors are all fixedly connected with the top inner wall of the treatment tube, the output ends of the linear motors are all fixedly connected with electric motors I, the output ends of the electric motors I are all connected with brushes through shaft couplings, the outer sides of the two brushes are respectively in contact with the outer sides of the coarse-hole filter screen and the electrostatic dust removal screen, and the outer sides of the linear motors are all provided with protection plates, the upper sides of the protection plates are all fixedly connected with the top inner wall of the treatment tube, the inner wall of the treatment tube is provided with a curved groove, the inner wall of the curved groove is movably connected with a rotating shaft, and the top end of the rotating shaft penetrates through the treatment tube and is located outside the treatment tube; the outer side of the rotating shaft is provided with a fixed ring, the bottom of the fixed ring is fixedly connected with the upper side of the treatment tube, the inner wall of the fixed ring is fixedly connected with a coil spring, one end of the coil spring away from the fixed ring is fixedly connected with the outer side of the rotating shaft, the rotating shaft is located between the electrostatic dust removal screen and the HEPA filter screen, and the outer side of the rotating shaft is fixedly connected with an isolation curtain, the inner wall of the treatment tube is fixedly connected with a limiting frame, a narrow groove is formed in the limiting frame, and the inner wall of the narrow groove is slidably connected with one end of the isolation curtain away from the rotating shaft; one side of the mounting plate close to the treatment tube is provided with a slot, the slot is fixedly connected with a boss, the boss is movably connected with a winding roller, the outer side of the winding roller is fixedly connected with a steel wire rope, one end of the steel wire rope away from the winding roller is fixedly connected with one end of the isolation curtain located in the narrow groove, and the outer side of the boss is fixedly connected with an electric motor II, and the output end of the electric motor II is connected with the upper side of the winding roller through a shaft coupling; two equidistantly distributed rectangular grooves are formed in the mounting plate, the two rectangular grooves are respectively located outside the coarse-hole filter screen and the electrostatic dust removal screen, a flow groove is formed in the mounting plate, the flow groove is communicated with the two rectangular grooves, a sealing plate is slidably connected in the flow groove, the outer side of the mounting plate is fixedly connected with a hydraulic rod, the output end of the hydraulic rod is fixedly connected with the outer side of the sealing plate, and two symmetrical storage grooves are formed in the inner wall of the flow groove, the inner wall of one side of the storage grooves away from the sealing plate is provided with a cutting groove, and the cutting groove is fixedly connected with a fine-hole filter plate.

[0011] In a preferred scheme, the quick replacement module comprises two symmetrical stabilizing frames, the inner walls of the two storage tanks are fixedly connected with the outsides of the stabilizing frames on the same side, the outsides of the stabilizing frames are fixedly connected with four symmetrical latches, the outsides of the four latches on the same side are inserted with the same mounting frame, the outsides of the mounting frames are fixedly connected with fiber filter bags, the fiber filter bags are located in the storage tanks, and the outsides of the fine-pore filter plates are provided with notches, and the notches are slidably connected with hard rods; the sides opposite to the mounting frames of the hard rods are fixedly connected, the ends away from the mounting frames of the hard rods are provided with notches, the notches are slidably connected with rotating rods, and the outsides of the rotating rods are slidably connected with sleeves; the outsides of the two sleeves are fixedly connected with the outside of the mounting plate, L-shaped grooves are formed in the sleeves, the L-shaped grooves are connected with locking pins, the sides opposite to the rotating rods of the locking pins are fixedly connected, the outsides of the rotating rods are surrounded with springs, one end of the springs is fixedly connected with the outside of the hard rod on the same side, and the other end is fixedly connected with the outside of the rotating rod on the same side.

[0012] As can be seen from the above, the coal mine low-concentration gas and wind exhaust gas flameless oxidation flue gas backflow utilization system provided by the application has the advantages that part of the exhaust gas backflow gas can replace part of the air as primary and secondary mixed gas, so that the gas temperature entering the RTO flameless heat accumulation oxidation device is increased, the high-temperature flue gas amount in the waste heat boiler is increased, the high-temperature and high-pressure steam output in the waste heat boiler is increased, the exhaust gas temperature of the waste heat boiler is reduced, the feed water preheater is added behind the economizer, the inlet water temperature entering the economizer is increased, the final exhaust gas temperature is reduced, the waste heat utilization rate is increased, and the power generation capacity or the heat supply capacity or the cogeneration output is increased, and the carbon emission reduction amount is increased. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 The device flow chart structure schematic diagram of the coal mine low-concentration gas and wind exhaust gas flameless oxidation flue gas backflow utilization system provided by the application is shown in the figure;

[0014] Figure 2 The overall structure schematic diagram of the processing pipe of the coal mine low-concentration gas and wind exhaust gas flameless oxidation flue gas backflow utilization system provided by the application is shown in the figure;

[0015] Figure 3 The cross-sectional structure schematic diagram of the processing pipe of the coal mine low-concentration gas and wind exhaust gas flameless oxidation flue gas backflow utilization system provided by the application is shown in the figure;

[0016] Figure 4 The particle cleaning module structure schematic diagram of the coal mine low-concentration gas and wind exhaust gas flameless oxidation flue gas backflow utilization system provided by the application is shown in the figure;

[0017] Figure 5 The limiting frame structure schematic diagram of the coal mine low-concentration gas and wind exhaust gas flameless oxidation flue gas backflow utilization system provided by the application is shown in the figure;

[0018] Figure 6 The installation plate structure diagram of the coal mine low-concentration gas and air exhaust gas flameless oxidation flue gas backflow utilization system;

[0019] Figure 7 The quick replacement module structure diagram of the coal mine low-concentration gas and air exhaust gas flameless oxidation flue gas backflow utilization system.

[0020] In the figure: 1, low-concentration gas conveying pipe; 2, three-proofing device; 3, air conveying pipe one; 4, flue gas backflow pipe; 5, primary mixing device; 6, methane concentration detector one; 7, temperature detector one; 8, primary mixed gas pipe; 9, air conveying pipe two; 10, flue gas backflow pipe two; 11, secondary mixing device; 12, secondary mixed gas pipe; 13, methane concentration detector two; 14, temperature detector two; 15, RTO fan; 16, RTO flameless regenerative oxidation device; 17, top flue gas pipe; 18, waste heat boiler; 19, high-pressure steam pipe; 20, water-steam heat exchanger; 21, condensing steam turbine; 22, generator; 23, waste heat flue gas pipe; 24, coal economizer; 25, temperature detector three; 26, feedwater preheater; 27, temperature detector four; 28, bottom flue gas pipe; 29, oxygen analyzer; 30, temperature detector five; 31, flue gas discharge pipe; 32, flue gas backflow pipe; 33, treatment pipe; 34, installation plate; 35, fixed frame; 36, coarse mesh filter screen; 37, electrostatic dust removal screen; 38, HEPA filter screen; 39, particulate matter cleaning module; 3901, linear motor; 3902, electric motor one; 3903, brush; 3904, protection plate; 3905, rotating shaft; 3906, coil spring; 3907, fixed ring; 3908, isolation curtain; 3909, limiting frame; 3910, rectangular groove; 3911, wire winding roller; 3912, steel wire rope; 3913, electric motor two; 3914, flow groove; 3915, closing plate; 3916, hydraulic rod; 3917, storage groove; 3918, fine mesh filter plate; 40, quick replacement module; 4001, stabilizing frame; 4002, bolt; 4003, installation frame; 4004, fiber filter bag; 4005, hard rod; 4006, rotating rod; 4007, sleeve; 4008, L-shaped groove; 4009, locking pin; 4010, spring; 41, backflow fan; 42, particulate matter treatment device. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all.

[0022] The coal mine low-concentration gas and air exhaust gas flameless oxidation flue gas backflow utilization system disclosed by the application is mainly applied to the scene with high gas dust content in the existing coal mine low-concentration gas and air exhaust gas utilization system.

[0023] With reference to Figure 1 The coal mine low-concentration gas and air exhaust gas flameless oxidation flue gas backflow utilization system comprises:

[0024] A low-concentration gas conveying pipe 1 is provided with a three-proofing device 2, and is connected with a first-stage mixing device 5.

[0025] An air conveying pipe 1 is connected with the first-stage mixing device 5, and the first-stage mixing device 5 is connected with a first-stage mixed gas pipe 8.

[0026] An air conveying pipe 2 is connected with a second-stage mixing device 11, the second-stage mixing device 11 is connected with a second-stage mixed gas pipe 12, the second-stage mixed gas pipe 12 is connected with an RTO fan 15, and the RTO fan 15 is connected with an RTO flameless heat accumulation oxidation device 16.

[0027] A flue gas backflow pipe 32 is connected with the bottom flue gas pipe 28, and is connected with a flue gas backflow pipe 2 and a flue gas backflow pipe 4, the flue gas backflow pipe 2 is connected with the air conveying pipe 2, the flue gas backflow pipe 4 is connected with the air conveying pipe 1, and a particulate matter treatment device 42 is arranged on the low-concentration gas conveying pipe 1.

[0028] The secondary mixed gas pipe 12 is provided with a methane concentration detector 13 and a temperature detector 14, the top flue gas pipe 17 is provided with a waste heat boiler 18, the waste heat boiler 18 is connected with a high-pressure steam pipe 19, the high-pressure steam pipe 19 is connected with a steam-water heat exchanger 20 and a condensing steam turbine 21, the condensing steam turbine 21 is connected with a generator 22, the waste heat flue gas pipe 23 is provided with an economizer 24, a temperature detector 25, a feedwater preheater 26 and a temperature detector 27, and the bottom flue gas pipe 28 is provided with an oxygen analyzer 29 and a temperature detector 30, the primary mixed gas pipe 8 is provided with a methane concentration detector 6 and a temperature detector 7, and the primary mixed gas pipe 8 is connected with the secondary mixing device 11, the RTO flameless heat storage oxidation device 16 is provided with the top flue gas pipe 17 and the bottom flue gas pipe 28, the top flue gas pipe 17 is connected with the waste heat flue gas pipe 23, the waste heat flue gas pipe 23 is connected with the bottom flue gas pipe 28, the bottom flue gas pipe 28 is connected with a flue gas discharge pipe 31, and the flue gas return pipe 32 is provided with a return fan 41. The oxygen analyzer is arranged here, which can measure the residual oxygen content of the flue gas, and the residual oxygen content must be greater than 6%; if the oxygen content is reduced, the gas cannot be fully burned, and the destruction of the gas cannot be guaranteed; in addition, the return can improve the inlet temperature of the RT, and the higher the inlet temperature of the heat storage body, the higher the heat recovery efficiency of the heat storage body, for example, when the inlet temperature is 20°, the utilization rate is 95%, and when the inlet temperature is higher than 60°, the utilization rate is increased to 98%.

[0029] The coal mine low-concentration gas and wind exhaust gas flameless oxidation flue gas return utilization system replaces part of air with part of flue gas return gas as primary and secondary mixed gas, thereby improving the gas temperature entering the RTO flameless heat storage oxidation device 16, improving the high-temperature flue gas amount in the waste heat boiler 18, improving the high-temperature high-pressure steam yield in the waste heat boiler 18, thereby improving the power generation capacity or heat supply capacity or cogeneration capacity, and improving the carbon emission reduction capacity; reducing the flue gas temperature of the waste heat boiler 18, adding the feedwater preheater 26 after the economizer 24, improving the inlet water temperature of the economizer 24, reducing the final flue gas temperature, and improving the waste heat utilization rate. The higher the flue gas return temperature, the higher the heat recovery efficiency of the heat storage body. The flue gas return can improve the utilization of the heat storage body, that is, the heat recovery utilization rate, and can also improve the heat recovery.

[0030] Reference Figures 2-6In a preferred embodiment, the particulate matter treatment device 42 comprises a treatment tube 33 arranged on the low-concentration gas conveying pipe 1, the outer wall of the treatment tube 33 is provided with a cutting groove, the inner wall of the cutting groove is connected with a mounting plate 34 through bolts, the inner wall of the treatment tube 33 is connected with three equidistantly distributed fixed frames 35 through bolts, the inner wall of each of the three fixed frames 35 is connected with a coarse hole filter screen 36, an electrostatic precipitation screen 37 and a HEPA filter screen 38 through bolts respectively, and the treatment tube 33 is provided with a particulate matter cleaning module 39, and the mounting plate 34 is provided with a quick replacement module 40; the particulate matter cleaning module 39 comprises two linear motors 3901, the two linear motors 3901 are respectively located on the side of the coarse hole filter screen 36 and the electrostatic precipitation screen 37 away from the bottom flue gas pipe 28, the outer wall of each of the linear motors 3901 is connected with the top inner wall of the treatment tube 33 through bolts, the output end of each of the linear motors 3901 is connected with a motor one 3902 through a bolt, the output end of the motor one 3902 is connected with a brush 3903 through a coupling, the outer part of each of the two brushes 3903 is in contact with the outer part of the coarse hole filter screen 36 and the electrostatic precipitation screen 37 respectively, and the outer wall of each of the linear motors 3901 is provided with a protection plate 3904, the upper side of the protection plate 3904 is connected with the top inner wall of the treatment tube 33 through bolts, the inner wall of the treatment tube 33 is provided with a curved groove, the inner wall of the curved groove is rotatably connected with a rotating shaft 3905 through a bearing, the top end of the rotating shaft 3905 penetrates through the treatment tube 33 and is located outside the treatment tube 33; the outer wall of the rotating shaft 3905 is provided with a fixing ring 3907, the bottom of the fixing ring 3907 is connected with the upper side of the treatment tube 33 through bolts, the inner wall of the fixing ring 3907 is connected with a coil spring 3906 through bolts, one end of the coil spring 3906 away from the fixing ring 3907 is connected with the outer wall of the rotating shaft 3905 through a bolt, the rotating shaft 3905 is located between the electrostatic precipitation screen 37 and the HEPA filter screen 38, and the outer wall of the rotating shaft 3905 is connected with a isolation curtain 3908 through a bolt, the inner wall of the treatment tube 33 is connected with a limiting frame 3909 through bolts, the limiting frame 3909 is provided with a narrow groove, and the inner wall of the narrow groove is slidably connected with one end of the isolation curtain 3908 away from the rotating shaft 3905; the side of the mounting plate 34 close to the treatment tube 33 is provided with a slot, the slot is connected with a boss through bolts, the boss is rotatably connected with a winding roller 3911 through a bearing, the outer wall of the winding roller 3911 is connected with a steel wire rope 3912 through a bolt, one end of the steel wire rope 3912 away from the winding roller 3911 is connected with one end of the isolation curtain 3908 in the narrow groove through a bolt, and the outer wall of the boss is connected with a motor two 3913 through a bolt, the output end of the motor two 3913 is connected with the upper side of the winding roller 3911 through a coupling.Two equidistantly distributed rectangular grooves 3910 are formed on the mounting plate 34, and the two rectangular grooves 3910 are located outside the coarse hole filter screen 36 and the electrostatic dust removal screen 37 respectively. A flow groove 3914 is formed on the mounting plate 34, and the flow groove 3914 is communicated with the two rectangular grooves 3910. A closing plate 3915 is slidably connected in the flow groove 3914. A hydraulic rod 3916 is connected to the outside of the mounting plate 34 by bolts. The output end of the hydraulic rod 3916 is connected to the outside of the closing plate 3915 by bolts. Two symmetrical storage grooves 3917 are formed in the inner wall of the flow groove 3914. A cutout is formed in the inner wall of the side of each storage groove 3917 away from the closing plate 3915. A fine hole filter plate 3918 is connected in the cutout by bolts.

[0031] In a specific application scenario, the particulate matter cleaning module 39 is suitable for the particulate matter cleaning link in the particulate matter cleaning process. That is, the particulate matter cleaning module 39 can effectively intercept the particulate matter flowing in the low-concentration gas conveying pipe 1 by using the coarse hole filter screen 36, the electrostatic dust removal screen 37 and the HEPA filter screen 38, so as to avoid the particulate matter from adhering and accumulating in the low-concentration gas conveying pipe 1, causing the pipe diameter of the low-concentration gas conveying pipe 1 to become smaller or even causing the low-concentration gas conveying pipe 1 to be blocked, thereby ensuring the smooth flow of gas in the low-concentration gas conveying pipe 1. The particulate matter accumulated on the coarse hole filter screen 36 and the electrostatic dust removal screen 37 can be cleaned by using the brush 3903. The particulate matter cleaned is sent to the storage groove 3917 through the air flow branch formed by the isolation curtain 3908 and the flow groove 3914, so as to ensure the continuous and effective filtering function of the coarse hole filter screen 36 and the electrostatic dust removal screen 37, improve the service life of the device, effectively reduce the dust content in the gas by removing the particulate matter in the gas, reduce the risk of dust explosion, improve the safety, and avoid the accumulation of dust in the regenerator of the RTO flameless regenerative oxidation device 16, reduce the resistance of flue gas flow, and reduce the energy consumption.

[0032] Reference Figure 7In a preferred implementation, the quick replacement module 40 comprises two symmetrical stabilizing frames 4001, the inner walls of the two storage grooves 3917 are each bolted to the outer part of the stabilizing frame 4001 on the same side, the outer part of the stabilizing frame 4001 is bolted to four symmetrical latches 4002, the outer part of the four latches 4002 on the same side is inserted with the same mounting frame 4003, the outer part of the mounting frame 4003 is bolted to the fiber filter bag 4004, the fiber filter bag 4004 is located in the storage groove 3917, and the outer part of the fine pore filter plate 3918 is provided with a notch, and the hard rod 4005 is slidably connected in the notch; the side opposite to the mounting frame 4003 of the hard rod 4005 on the same side is bolted, the end of the hard rod 4005 away from the mounting frame 4003 is provided with a hole, the rotating rod 4006 is slidably connected in the hole, and the outer part of the rotating rod 4006 is slidably connected with the sleeve 4007; the outer part of the two sleeves 4007 is bolted to the outer part of the mounting plate 34, the L-shaped slot 4008 is provided on the sleeve 4007, the locking pin 4009 is clamped in the L-shaped slot 4008, the side opposite to the rotating rod 4006 of the locking pin 4009 is bolted, and the outer part of the rotating rod 4006 is surrounded by the spring 4010, one end of the spring 4010 is bolted to the outer part of the hard rod 4005 on the same side, and the other end is bolted to the outer part of the rotating rod 4006 on the same side.

[0033] In a specific application scenario, the quick replacement module 40 is mainly suitable for the quick replacement link in the quick replacement process, that is, the mounting frame 4003 connected with the fiber filter bag 4004 can be stably fixed in the storage groove 3917 by the stabilizing frame 4001 and the latch 4002, so that the particulate matter cleaned can be completely collected by the fiber filter bag 4004, the installation and disassembly of the fiber filter bag 4004 can be quickly completed by the locking pin 4009 and the L-shaped slot 4008, the disassembly and replacement efficiency of the fiber filter bag 4004 is improved, the cleaning function of the device on the particulate matter is ensured to be unaffected, and the fluency is improved.

[0034] Working principle: low concentration gas in coal mine flows in low concentration gas conveying pipe 1, after conveying through mine three-proofing device 2, it is uniformly mixed with air in air conveying pipe one 3 and part of exhaust gas backflow in exhaust gas backflow pipe 4 in primary mixing device 5, after primary mixing, gas is uniformly mixed with air in air conveying pipe two 9 and part of exhaust gas backflow in exhaust gas backflow pipe two 10 in secondary mixing device 11, after conveying through RTO fan 15, it is flameless oxidized in RTO flameless heat accumulating oxidation device 16, through exhaust gas backflow mixing, after gas enters RTO flameless heat accumulating oxidation device 16, its temperature is increased from original ambient temperature to about 80 degrees Celsius, the amount of flue gas in top exhaust pipe 17 at the top of RTO flameless heat accumulating oxidation device 16 is greatly increased, high temperature and high pressure steam generated by waste heat boiler 18 flows in high pressure steam pipe 19, so that condensing steam turbine 21 generates electricity by generator 22, or goes to steam-water heat exchanger 20 to generate hot water for heating or bathing, etc., the flue gas from waste heat boiler 18 flows from waste heat exhaust pipe 23, after passing through economizer 24 and feed water preheater 26, it is combined with bottom flue gas in bottom flue gas pipe 28 and goes to chimney; when flue gas flows, coarse hole filter screen 36 filters large particle solid particles, electrostatic dust removal screen 37 filters medium particle solid particles, HEPA filter screen 38 filters small particle solid particles, hydraulic rod 3916 is started, hydraulic rod 3916 pushes closing plate 3915 out of flowing groove 3914, motor two 3913 is started, so that winding roller 3911 winds up steel wire rope 3912, and sliding curtain 3908 is unfolded in limiting frame 3909, so that processing pipe 33 is closed, flue gas flows into storage tank 3917 through flowing groove 3914, motor one 3902 and linear motor 3901 are started, so that linear motor 3901 drives rotating brush 3903 to clean particles adhered to coarse hole filter screen 36 and electrostatic dust removal screen 37, the cleaned particles enter fiber filter bag 4004 in storage tank 3917 through rectangular groove 3910 along with airflow, after cleaning is completed, closing plate 3915 is closed, rotating rod 4006 is rotated, so that locking pin 4009 is disengaged from clamping of L-shaped groove 4008, under the action of spring 4010, mounting frame 4003 is separated from stabilizing frame 4001, fine hole filter plate 3918 is removed, fiber filter bag 4004 full of particles is taken out, and new fiber filter bag 4004 is reinstalled according to the above steps.

[0035] The gas quantity is 20m 3 / min, and the important parameter comparison before and after the hot flue gas backflow (the heating time is 3600h in winter, and the power generation time is 4400h in other seasons)

[0036] Parameter comparison table before and after the hot flue gas backflow

[0037]

[0038]

[0039] By replacing part of the air with hot flue gas backflow as primary and secondary mixed air for heat recovery, the steam quantity, power generation quantity, heat supply quantity and carbon emission reduction quantity are significantly improved, thereby significantly improving the income.

[0040] The above merely describes the preferred embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art, according to the technical solution and inventive concept of the present application, makes equivalent replacement or change within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A coal mine low-concentration gas and air exhaust gas flameless oxidation flue gas backflow utilization system, characterized in that, The utility model relates to a low concentration gas conveying pipe (1) which is provided with a three-proofing device (2) and is connected with a first-level mixing device (5), an air conveying pipe (3) which is connected with the first-level mixing device (5) and the first-level mixing device (5) which is connected with a first-level mixed gas pipe (8), an air conveying pipe (9) which is connected with a second-level mixing device (11) and the second-level mixing device (11) which is connected with a second-level mixed gas pipe (12), the second-level mixed gas pipe (12) is connected with an RTO fan (15), the RTO fan (15) is connected with an RTO flameless heat accumulation oxidation device (16), a flue gas return pipe (32) which is connected with a bottom flue gas pipe (28), the flue gas return pipe (32) is connected with a flue gas return pipe (4) and a flue gas return pipe (10), the flue gas return pipe (10) is connected with the air conveying pipe (9), and the flue gas return pipe (4) is connected with the air conveying pipe (3), and the low concentration gas conveying pipe (1) is provided with a particulate matter treatment device (42). The particulate matter treatment device (42) comprises a treatment pipe (33) arranged on the low concentration gas conveying pipe (1), a cutting groove is formed in the outer portion of the treatment pipe (33), the cutting groove is fixedly connected with a mounting plate (34), the inner wall of the treatment pipe (33) is fixedly connected with three equidistantly distributed fixed frames (35), the inner walls of the three fixed frames (35) are fixedly connected with a coarse mesh filter (36), an electrostatic dust removal net (37) and a HEPA filter (38) respectively, and the treatment pipe (33) is provided with a particulate matter cleaning module (39), and the mounting plate (34) is provided with a quick replacement module (40). The particulate matter cleaning module (39) comprises two linear motors (3901), the two linear motors (3901) are located on the sides of the coarse mesh filter (36) and the electrostatic dust removal net (37) away from the bottom flue gas pipe (28) respectively, the outer portions of the linear motors (3901) are fixedly connected with the top inner wall of the treatment pipe (33), the output ends of the linear motors (3901) are fixedly connected with electric motors (3902), the output ends of the electric motors (3902) are connected with brushes (3903) through shaft couplings, the outer portions of the two brushes (3903) are in contact with the outer portions of the coarse mesh filter (36) and the electrostatic dust removal net (37) respectively, the outer portions of the linear motors (3901) are provided with protection plates (3904), the upper sides of the protection plates (3904) are fixedly connected with the top inner wall of the treatment pipe (33), the inner wall of the treatment pipe (33) is provided with a curved groove, the curved groove is movably connected with a rotating shaft (3905), and the top end of the rotating shaft (3905) penetrates through the treatment pipe (33) and is located outside the treatment pipe (33). ​ ​ ​ ​ ​ 2. The coal mine low-concentration gas and air exhausted gas flameless oxidation flue gas backflow utilization system according to claim 1, characterized in that, The secondary mixed gas pipe (12) is provided with a methane concentration detector two (13) and a temperature detector two (14), the top smoke exhaust pipe (17) is provided with a waste heat boiler (18), the waste heat boiler (18) is connected with a high-pressure steam pipe (19), the high-pressure steam pipe (19) is connected with a steam-water heat exchanger (20) and a condensing steam turbine (21), the condensing steam turbine (21) is connected with a generator (22), the waste heat smoke exhaust pipe (23) is provided with an economizer (24), a temperature detector three (25), a feedwater preheater (26) and a temperature detector four (27), and the bottom smoke pipe (28) is provided with an oxygen analyzer (29) and a temperature detector five (30), the primary mixed gas pipe (8) is provided with a methane concentration detector one (6) and a temperature detector one (7), and the primary mixed gas pipe (8) is connected with a secondary mixing device (11), the RTO flameless heat accumulation oxidation device (16) is provided with a top smoke exhaust pipe (17) and a bottom smoke pipe (28), the top smoke exhaust pipe (17) is connected with a waste heat smoke exhaust pipe (23), the waste heat smoke exhaust pipe (23) is connected with the bottom smoke pipe (28), the bottom smoke pipe (28) is connected with a flue gas discharge pipe (31), and the flue gas return pipe (32) is provided with a return fan (41).

3. The coal mine low-concentration gas and air exhausted gas flameless oxidation flue gas backflow utilization system according to claim 1, characterized in that, The outer portion of the rotating shaft (3905) is provided with a fixing ring (3907), the bottom of the fixing ring (3907) is fixedly connected with the upper side of the treatment pipe (33), the inner wall of the fixing ring (3907) is fixedly connected with a coil spring (3906), one end of the coil spring (3906) away from the fixing ring (3907) is fixedly connected with the outer portion of the rotating shaft (3905), the rotating shaft (3905) is located between the electrostatic dust removal net (37) and the HEPA filter screen (38), and the outer portion of the rotating shaft (3905) is fixedly connected with a isolation curtain (3908), the inner wall of the treatment pipe (33) is fixedly connected with a limiting frame (3909), a narrow slot is formed in the limiting frame (3909), and the inner wall of the narrow slot is slidably connected with one end of the isolation curtain (3908) away from the rotating shaft (3905).

4. The coal mine low-concentration gas and air exhausted gas flameless oxidation flue gas backflow utilization system according to claim 3, characterized in that, The mounting plate (34) is provided with a notch on one side close to the treatment pipe (33), a boss is fixedly connected in the notch, a wire winding roller (3911) is movably connected on the boss, a steel wire rope (3912) is fixedly connected with the outer portion of the wire winding roller (3911), one end of the steel wire rope (3912) away from the wire winding roller (3911) is fixedly connected with one end of the isolation curtain (3908) in the narrow slot, and the outer portion of the boss is fixedly connected with a motor two (3913), and the output end of the motor two (3913) is connected with the upper side of the wire winding roller (3911) through a shaft coupling.

5. The coal mine low-concentration gas and air exhausted gas flameless oxidation flue gas backflow utilization system according to claim 4, characterized in that, Two equidistant rectangular grooves (3910) are arranged on the mounting plate (34), and the two rectangular grooves (3910) are located outside the coarse hole filter screen (36) and the electrostatic dust removal screen (37) respectively. A flow groove (3914) is arranged on the mounting plate (34), the flow groove (3914) is communicated with the two rectangular grooves (3910), a closing plate (3915) is slidably connected in the flow groove (3914), a hydraulic rod (3916) is fixedly connected to the outside of the mounting plate (34), the output end of the hydraulic rod (3916) is fixedly connected to the outside of the closing plate (3915), and two symmetrical storage grooves (3917) are arranged on the inner wall of the flow groove (3914). The inner wall of the side, away from the closing plate (3915), of each storage groove (3917) is provided with a notch, and a fine hole filter plate (3918) is fixedly connected in the notch.

6. The coal mine low-concentration gas and air exhausted gas flameless oxidation flue gas backflow utilization system according to claim 1, characterized in that, The quick replacement module (40) comprises two symmetrical stable frames (4001), the inner walls of the two storage grooves (3917) are fixedly connected to the outside of the stable frame (4001) on the same side, four symmetrical latches (4002) are fixedly connected to the outside of the stable frame (4001), the same side four latches (4002) are inserted with the same mounting frame (4003), the mounting frame (4003) is fixedly connected with a fiber filter bag (4004) on the outside, the fiber filter bag (4004) is located in the storage groove (3917), and the outside of the fine hole filter plate (3918) is provided with a notch, and a hard rod (4005) is slidably connected in the notch.

7. The coal mine low-concentration gas and air exhausted gas flameless oxidation flue gas backflow utilization system according to claim 6, characterized in that, The hard rod (4005) is fixedly connected to the side opposite to the mounting frame (4003) on the same side, and the end of the hard rod (4005) away from the mounting frame (4003) is provided with a hole, and a rotating rod (4006) is slidably connected in the hole.

8. The coal mine low-concentration gas and air exhausted gas flameless oxidation flue gas backflow utilization system according to claim 7, characterized in that, The outside of the two sleeves (4007) is fixedly connected to the outside of the mounting plate (34), and an L-shaped groove (4008) is arranged on the sleeve (4007), a locking pin (4009) is clamped in the L-shaped groove (4008), the locking pin (4009) is fixedly connected to the side opposite to the rotating rod (4006), and a spring (4010) is arranged around the outside of the rotating rod (4006), one end of the spring (4010) is fixedly connected to the outside of the hard rod (4005) on the same side, and the other end is fixedly connected to the outside of the rotating rod (4006).

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