Dry quenching flue gas CO removal device

Abstract

The utility model belongs to the technical field of environmental protection equipment, and particularly relates to a dry quenching flue gas CO removal device, which is characterized by comprising a catalytic reactor, a flue gas preheater, an oil pump, a filter, a flue gas inlet header pipe and a flue gas outlet header pipe, an upper box body, a middle box body and a lower box body are arranged in the box body from top to bottom, a plurality of catalytic heat exchange tubes are vertically arranged in the middle box body, and a flue gas channel is formed between every two adjacent catalytic heat exchange tubes; a flue gas preheater is arranged on the flue gas inlet pipe, and an oil pump and a filter are connected to the heat-conducting oil inlet pipe; and a CO catalyst is sintered on the outer wall of the catalytic heat exchange tube. The device has the advantages that a feasible device design scheme is provided for a dry quenching flue gas pollution reduction and carbon reduction process route, the device can be matched with a flue gas desulfurization and dust removal system for use, the structure is compact, the occupied area is small, a heat source and a fan do not need to be additionally arranged, and the device can adapt to various production occasions.

Description

Technical Field

[0001] The utility model belongs to the technical field of environmental protection equipment, and in particular relates to a device for removing CO from dry quenching flue gas. Background Art

[0002] Coke dry quenching technology is a technology that uses inert gas to extinguish red coke in a closed system while recovering flue gas dust and waste heat. The coke dry quenching device continuously produces CO, H2 and SO2 during operation. The continuous accumulation of pollutants in the circulating nitrogen will endanger the safe operation of the equipment. The existing coke oven dry quenching flue gas treatment technology in the coking industry mainly focuses on removing sulfur dioxide and dust from the flue gas. The circulating flue gas of the dry quenching furnace usually contains 4% to 6% CO, which is currently discharged directly into the atmosphere without treatment. Efficient treatment of the high concentration of CO in the circulating exhaust gas of the dry quenching coke has both energy-saving and environmental protection significance. CO catalytic oxidation technology uses transition metals as catalysts to react with O2 to generate CO2. This technical route is suitable for the dry quenching exhaust gas temperature and can be well combined with upstream and downstream flue gas treatment methods. The efficient catalytic oxidation reactor helps to improve the reaction efficiency and better achieve the goal of CO treatment of the dry quenching exhaust gas.

[0003] The Chinese utility model patent with application number 202311221909.5 discloses a method, system and graded catalytic reactor for treating flue gas commonly used in dry coke quenching. The treatment method includes: pretreatment and catalytic oxidation of CO and H2. The graded catalytic reactor includes: an oxygen activation layer, which is used to activate oxygen molecules and water molecules, and the flue gas first passes through the oxygen activation layer; a catalyst layer, the flue gas activated by the oxygen activation layer enters the catalyst layer, which is used for catalytic oxidation of CO and H2; a temperature regulating layer, the temperature regulating layer is used to recover the heat in the catalytic oxidation reaction and adjust the temperature in the reactor. A part of the high-temperature clean flue gas is used to improve the catalytic reaction efficiency of CO and H2, and the other part is used for waste heat recovery to save energy. The graded catalytic reactor reduces the catalytic reaction temperature of CO and H2, effectively avoiding the problem of catalyst sintering damage caused by excessively high catalytic reaction temperature. The scheme adopts a configuration of catalytic temperature from low to high to achieve the utilization of catalytic reaction heat. The disadvantage is that the limitation of the catalytic temperature of multi-stage continuous reaction limits its application and cannot be adapted to a variety of production occasions. Utility Model Content

[0004] The purpose of the utility model is to provide a device for removing CO from dry coke quenching flue gas, which overcomes the shortcomings of the prior art, adopts a parallel reaction chamber structure to improve the catalytic efficiency, and a bypass heat transfer oil purification structure to enhance the regeneration capacity of the device, can be used in conjunction with a flue gas desulfurization and dust removal system, does not require additional heat sources and fans, and can be adapted to a variety of production occasions.

[0005] To achieve the above purpose, the utility model is implemented through the following technical solutions:

[0006] A device for removing CO from flue gas from dry coke quenching, characterized in that it comprises a catalytic reactor, a flue gas preheater, an oil pump, a filter, a flue gas inlet main pipe and a flue gas outlet main pipe, the catalytic reactor is composed of at least two independent reaction units connected in parallel, the reaction unit is a vertical box structure, an upper box, a middle box and a lower box are arranged in the box from top to bottom, the upper box and the middle box are separated by an upper flower plate, the middle box and the lower box are separated by a lower flower plate, the upper box is respectively connected to the flue gas outlet pipe and the heat transfer oil inlet pipe, The oil pipe is provided with a smoke exhaust valve on the smoke exhaust pipe, and an oil inlet valve on the heat transfer oil inlet pipe. The lower box is respectively connected to the smoke inlet pipe and the heat transfer oil return pipe, and the smoke inlet pipe is provided with a smoke inlet valve; a plurality of catalytic heat exchange tubes are vertically arranged in the middle box, and a smoke channel is provided between adjacent catalytic heat exchange tubes; a smoke preheater is provided on the smoke inlet pipe, an oil pump and a filter are connected to the heat transfer oil inlet pipe, and the oil inlet of the oil pump is connected to the heat transfer oil return pipe; CO catalyst is sintered on the outer wall of the catalytic heat exchange tube.

[0007] Furthermore, a heat recovery device is provided on the heat transfer oil return pipe, and the front and rear of the heat recovery device are connected through a short pipe. A short-circuit valve is provided on the short pipe, and the short-circuit valve is interlocked with the temperature signal T7 on the front end pipeline of the short pipe.

[0008] Furthermore, the middle box body is provided with spoilers, which are distributed in a staggered manner in high and low positions.

[0009] Furthermore, the heat transfer oil inlet pipe is connected to the top of each catalytic heat exchange tube through an oil inlet branch pipe; the heat transfer oil return pipe is connected to the bottom of each catalytic heat exchange tube through an oil return branch pipe.

[0010] Furthermore, the hot end of the flue gas preheater is a heat transfer oil return bypass pipe, a bypass valve is installed on the heat transfer oil return bypass pipe, the cold end is a flue gas inlet main pipe, and the flue gas preheater is a tubular heat exchange structure or a plate heat exchange structure.

[0011] Furthermore, the flue gas inlet main pipe is provided with pressure P1, flow rate Q1, temperature T1, and CO concentration monitoring point W1; the flue gas exhaust main pipe is provided with pressure P2, temperature T4, and CO concentration monitoring point W2; the thermal oil inlet pipe is provided with flow rate Q2 and temperature monitoring point T5; the thermal oil return bypass pipe is provided with flow rate Q3 and temperature T6 monitoring points; the flue gas preheater outlet pipeline is provided with a temperature T2 monitoring point; and the outer wall of the catalytic reactor is provided with a temperature T3 monitoring point.

[0012] Furthermore, an air introduction pipe is provided on the flue gas inlet main pipe, and an air introduction valve is provided on the air introduction pipe. The air introduction valve is interlocked with a CO concentration monitoring point W1 on the flue gas inlet main pipe for control.

[0013] Furthermore, an explosion relief diaphragm is provided on the outer wall of the middle box body, and an inspection port is opened.

[0014] Furthermore, the overall outer surface of the catalytic reactor and its connecting pipes are externally insulated; the flue gas preheater is externally insulated.

[0015] Compared with the prior art, the beneficial effects of the utility model are:

[0016] 1) The utility model provides a feasible device design scheme for the process route of CDQ flue gas pollution reduction and carbon reduction, which can be used in conjunction with the flue gas desulfurization and dust removal system. It has a compact structure and occupies a small area, does not require additional heat sources and fans, and can be adapted to a variety of production occasions.

[0017] 2) The catalytic heat exchange tube allows flue gas catalysis and waste heat recovery to proceed simultaneously. Compared with the traditional multi-stage catalytic reactor that reacts first and then cools, reacts again and then cools, the reaction temperature in this device is more uniform, the catalytic efficiency is higher, and the integration is better.

[0018] 3) The two reaction chambers are relatively independent and can be maintained online. Each instrument measurement point and control valve are program interlocked to ensure the reaction rate and safety of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of an embodiment of the utility model.

[0020] In the figure: 1-catalytic reactor, 2-flue gas preheater, 3-heat recovery device, 4-oil pump, 5-filter, 6-smoke inlet valve, 7-smoke inlet valve, 8-smoke exhaust valve, 9-smoke exhaust valve, 10-bypass valve, 11-oil inlet valve, 12-air introduction valve, 13-smoke inlet main pipe, 14-smoke exhaust main pipe, 15-short-circuit valve, 16-thermal oil inlet pipe, 17-smoke inlet pipe, 18-thermal oil return pipe, 19-short pipe, 20-thermal oil return bypass pipe, 21-air introduction pipe, 101-catalytic heat exchange pipe, 102-spoiler, 103-upper flower plate, 104-lower flower plate, 105-oil inlet branch pipe, 106-oil return branch pipe, 107-explosion relief diaphragm, 108-inspection hole. DETAILED DESCRIPTION

[0021] The technical solution of the present utility model will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present utility model, rather than all of the embodiments.

[0022] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the specific embodiments required to be used in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the specific embodiments described below are some implementation methods of the utility model. For ordinary technicians in this field, other specific embodiments can be obtained based on these specific embodiments without paying creative work.

[0023] The components of the embodiments of the present invention generally described and shown in the specific embodiments herein can be arranged and designed in countless different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the specific embodiments is not intended to limit the scope of the utility model claimed, but only represents the selected embodiments of the utility model.

[0024] See Figure 1 , is a schematic diagram of the structure of an embodiment of a dry coke quenching flue gas CO removal device of the utility model, comprising a catalytic reactor 1, a flue gas preheater 2, an oil pump 4, a filter 5, a flue gas inlet main pipe 13 and a flue gas exhaust main pipe 14, the catalytic reactor 1 is composed of two independent reaction units connected in parallel, the reaction unit is a vertical box structure, an upper box, a middle box and a lower box are arranged in the box from top to bottom, the upper box and the middle box are separated by an upper flower plate 103, the middle box and the lower box are separated by a lower flower plate 104, the upper box is connected to a flue gas exhaust pipe 15 and a heat transfer oil inlet pipe 16 respectively, the flue gas exhaust pipe 15 is provided with exhaust valves 8 and 9, the heat transfer oil inlet pipe An oil inlet valve 11 is provided on 16, and the lower box is respectively connected to a flue gas inlet pipe 17 and a heat transfer oil return pipe 18, and a flue gas inlet valve 6 and 7 are provided on the flue gas inlet pipe 17; a plurality of catalytic heat exchange tubes 101 are vertically arranged in the middle box, and a flue gas channel is provided between adjacent catalytic heat exchange tubes 101; a flue gas preheater 2 is provided on the flue gas inlet pipe 17, an oil pump 4 and a filter 5 are connected to the heat transfer oil inlet pipe 16, and the oil inlet of the oil pump 4 is connected to the heat transfer oil return pipe 18; the heat transfer oil inlet pipe 16 is connected to the top of each catalytic heat exchange tube 101 through an oil inlet branch pipe 105; the heat transfer oil return pipe 18 is connected to the bottom of each catalytic heat exchange tube 101 through an oil return branch pipe 106. The hot end of the flue gas preheater 2 is a heat transfer oil return bypass pipe 20, a bypass valve 10 on the heat transfer oil return bypass pipe 20, and the cold end is a flue gas inlet main pipe 13. The flue gas preheater 2 is a tubular heat exchange structure or a plate heat exchange structure.

[0025] The catalytic heat exchange tube 101 is a cylindrical structure. The outer wall of the catalytic heat exchange tube 101 is sintered with CO catalyst. The upper and lower parts of the catalytic heat exchange tube 101 are respectively provided with flanges, which are vertically fixed between the upper plate 103 and the lower plate 104. The flue gas completes the catalytic oxidation reaction on the outer tube wall of the catalytic heat exchange tube 101. The heat transfer oil flows from top to bottom in the catalytic heat exchange tube 101, and exchanges heat with the flue gas in the reverse direction. The lower box body is reserved for the discharge of dust. An air introduction pipe 21 is provided on the flue gas inlet main pipe 13, and an air introduction valve 12 is provided on the air introduction pipe 21. The air introduction valve 12 is interlocked with the CO concentration monitoring point W1 on the flue gas inlet main pipe 13. When the CO concentration is greater than 6%, the air introduction valve 12 is opened, and closed in other cases.

[0026] The utility model device is arranged after the flue gas desulfurization and dust removal device, and each reaction unit is integrated in parallel, with the exhaust air induced draft fan as the power source, and the flue gas flows from bottom to top along the device and then is discharged. When a reaction unit needs to be repaired, the corresponding smoke inlet valve of the reaction unit is closed, and the remaining reaction units can work normally, realizing online maintenance.

[0027] A heat recovery device 3 is provided on the heat transfer oil return pipe 18, and the front and rear of the heat recovery device 3 are connected through a short pipe 19. A short-circuit valve 15 is provided on the short pipe 19, and the short-circuit valve 15 is interlocked with the temperature signal T7 on the front end of the short pipe. In order to improve the catalytic efficiency, a spoiler 102 is provided in the middle box body, and the spoiler 102 is staggered in high and low positions in the middle box body to increase the contact time between the flue gas and the CO catalyst.

[0028] In order to improve the level of automatic control, pressure P1, flow rate Q1, temperature T1 and CO concentration monitoring point W1 are provided on the flue gas inlet main pipe 13; pressure P2, temperature T4 and CO concentration monitoring point W2 are provided on the flue gas exhaust main pipe 14; flow rate Q2 and temperature monitoring point T5 are provided on the thermal oil inlet pipe 16; flow rate measuring point Q4 is provided on the thermal oil return bypass pipe 20; flow rate Q3 and temperature T6 monitoring points are provided on the thermal oil return pipe 18; a temperature T2 monitoring point is provided on the outlet pipeline of the flue gas preheater 2; and a temperature T3 monitoring point is provided on the outer wall of the catalytic reactor 1.

[0029] In the embodiment of the utility model, the temperature control mechanism of the flue gas preheater 2 is as follows: when the flue gas inlet temperature is less than 180°C, the bypass valve 10 is opened to make the flue gas temperature at the inlet of the catalytic reactor 1 reach 180°C; the flow rate Q1 of the flue gas entering the main pipe 13, the CO concentration W1 and the opening of the flue gas inlet valves 6 and 7 are interlockedly controlled to control the catalytic rate; the opening of the oil inlet valve 11 is adjusted based on the temperature difference between the flue gas entering the main pipe 13 and the flue gas exhausting the main pipe 14 to maintain the temperature fluctuation value in the reaction unit not greater than ±2°C.

[0030] In order to make the catalytic reactor 1 safer and easier to maintain, an explosion relief diaphragm 107 is provided on the outer wall of the middle box, and an inspection port is provided. In order to make the catalytic reaction more stable, the entire outer surface of the catalytic reactor 1 and its connecting pipes are externally insulated; the flue gas preheater 2 is externally insulated.

[0031] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A device for removing CO from dry quenching flue gas, characterized in that: The invention comprises a catalytic reactor, a flue gas preheater, an oil pump, a filter, a flue gas inlet main pipe and a flue gas outlet main pipe. The catalytic reactor is composed of at least two independent reaction units connected in parallel. The reaction unit is a vertical box structure. An upper box, a middle box and a lower box are arranged in the box from top to bottom. The upper box and the middle box are separated by an upper flower plate, and the middle box and the lower box are separated by a lower flower plate. The upper box is respectively connected to the flue gas outlet pipe and the heat transfer oil inlet pipe. There is a smoke exhaust valve, and the heat transfer oil inlet pipe is provided with an oil inlet valve. The lower box is connected to the smoke inlet pipe and the heat transfer oil return pipe respectively, and the smoke inlet pipe is provided with a smoke inlet valve; a plurality of catalytic heat exchange tubes are vertically arranged in the middle box, and a smoke channel is provided between adjacent catalytic heat exchange tubes; a smoke preheater is provided on the smoke inlet pipe, and the heat transfer oil inlet pipe is connected to an oil pump and a filter, and the oil inlet of the oil pump is connected to the heat transfer oil return pipe; CO catalyst is sintered on the outer wall of the catalytic heat exchange tube.

2. A device for removing CO from dry quenching flue gas according to claim 1, characterized in that: The heat transfer oil return pipe is provided with a heat recovery device, the front and rear of the heat recovery device are connected through a short pipe, a short-circuit valve is provided on the short pipe, and the short-circuit valve is interlocked with the temperature signal T7 on the front end pipeline of the short pipe.

3. The device for removing CO from dry quenching flue gas according to claim 1, characterized in that: The middle box body is provided with spoilers, which are distributed in a staggered manner in high and low positions.

4. The device for removing CO from dry coke quenching flue gas according to claim 1, characterized in that: The heat transfer oil inlet pipe is connected to the top of each catalytic heat exchange tube through the oil inlet branch pipe; the heat transfer oil return pipe is connected to the bottom of each catalytic heat exchange tube through the oil return branch pipe.

5. The device for removing CO from dry coke quenching flue gas according to claim 1, characterized in that: The hot end of the flue gas preheater is a heat transfer oil return bypass pipe, a bypass valve on the heat transfer oil return bypass pipe, and the cold end is a flue gas inlet main pipe. The flue gas preheater is a tubular heat exchange structure or a plate heat exchange structure.

6. The device for removing CO from dry quenching flue gas according to claim 1, characterized in that: The flue gas inlet main pipe is provided with pressure P1, flow rate Q1, temperature T1, and CO concentration monitoring point W1; the flue gas exhaust main pipe is provided with pressure P2, temperature T4, and CO concentration monitoring point W2; the heat transfer oil inlet pipe is provided with flow rate Q2 and temperature monitoring point T5; the heat transfer oil return bypass pipe is provided with flow rate Q3 and temperature T6 monitoring points; the flue gas preheater outlet pipeline is provided with a temperature T2 monitoring point; and the outer wall of the catalytic reactor is provided with a temperature T3 monitoring point.

7. The device for removing CO from dry quenching flue gas according to claim 1, characterized in that: An air introduction pipe is provided on the flue gas inlet main pipe, and an air introduction valve is provided on the air introduction pipe. The air introduction valve is interlocked with a CO concentration monitoring point W1 on the flue gas inlet main pipe for control.

8. The device for removing CO from dry coke quenching flue gas according to claim 1, characterized in that: An explosion relief diaphragm is arranged on the outer wall of the middle box body, and an inspection opening is opened.

9. The device for removing CO from dry quenching flue gas according to claim 1, characterized in that: The overall outer surface of the catalytic reactor and its connecting pipes are externally insulated; the flue gas preheater is externally insulated.

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