Tail gas treatment system for active coke production process

Abstract

In order to ensure the operation safety of the tail gas treatment system, the tail gas treatment system for the active coke production process provides three protection measures: firstly, a first bypass and a water-sealed tank are arranged, so that when the risk that the pressure of tail gas is increased due to blockage of a filter screen occurs, the first bypass and the water-sealed tank are communicated with each other; tail gas can be guided to the water-sealed tank and safely discharged out of the system; secondly, an interlocking protection system is established, and the system automatically controls actions of a high-temperature fan, a tail gas quick switching valve, an oxygenating quick switching valve and a nitrogen sealing valve according to the pressure in the combustion furnace and automatically adjusts according to a set process; and finally, a flame arrester is arranged on a tail gas pipeline, and a safety valve and an explosion venting sheet are additionally arranged on the combustion furnace and the buffer cooling tank, so that the safety of the whole system is enhanced.

Description

TECHNICAL FIELD

[0001] The utility model belongs to active carbon production technical field, concretely relates to a tail gas treatment system for active coke production process. BACKGROUND

[0002] In the production process of active coke, the tail gas produced in carbonization and activation process mainly contains CO, H2, CH=, alkane, olefin and coal tar and other volatile substances, these substances have the characteristics of flammable and explosive. At present, the methods for treating carbonization tail gas mainly include electric collection method and incineration method. Although the electric collection method can effectively treat tail gas, its investment cost is high, energy consumption is large, and a large amount of water vapor is needed, so it is not widely used in practical application. On the contrary, the incineration method converts organic matter into harmless substances such as carbon dioxide and water through combustion, which is simple to operate and has become the mainstream treatment method.

[0003] The incineration method generally re-directs the tail gas to the combustion chamber or combustion equipment for combustion treatment. The common combustion methods include electric heating furnace combustion method and incineration torch combustion method. Although the open direct combustion of incineration torch is simple to operate, it will produce a large amount of odor. The electric heating furnace is a closed combustion, but due to the flammable and explosive characteristics of the gas, there are still some safety problems such as explosion and other accidents, in emergency situations, rapid and effective emergency measures are needed to prevent accidents from expanding, and the electric heating furnace combustion method has more stringent requirements for safety. CONTENT OF THE UTILITY MODEL

[0004] In view of the problem that the existing tail gas treatment device has safety risk, the utility model provides a tail gas treatment system for active coke production process, which can cope with the risk of pressure rise, set the first bypass and water seal tank for pressure relief, ensure the safe discharge of tail gas, and at the same time is equipped with an interlocking control system, according to the pressure in the combustion furnace, the action of tail gas quick cut valve, oxygen supplement quick cut valve and nitrogen gas seal valve can intelligently control tail gas quick cut valve, oxygen supplement quick cut valve and nitrogen gas seal valve according to the pressure in the combustion furnace, to prevent safety risk in the tail gas treatment process. In order to further improve the safety, a flame arrester, a safety valve and a pressure relief sheet are also installed to strengthen the safety protection of pipeline and equipment.

[0005] In order to achieve the above purpose, the utility model adopts the following technical scheme:

[0006] The tail gas treatment system for the active coke production process comprises a cooling and decoking device, a tail gas pipeline, a water seal tank and a combustion furnace, the cooling and decoking device comprises a buffer cooling tank and a filter screen, the tail gas outlet of the active coke production device is communicated with the inlet of the buffer cooling tank, the outlet of the buffer cooling tank is communicated with the combustion furnace through the tail gas pipeline, the buffer cooling tank is used for cooling the tail gas discharged by the active coke production device, and the filter screen is arranged in the buffer cooling tank and used for removing the tar in the tail gas; the inlet of the water seal tank is communicated with the tail gas outlet of the active coke production device through a first bypass, an air inlet pipeline extending below the liquid level in the water seal tank is connected at the inlet of the water seal tank, and a vent is arranged at the top of the water seal tank.

[0007] In some embodiments, the tail gas treatment system further comprises a nitrogen purging device for purging the tail gas treatment system, the nitrogen purging device comprises a nitrogen gas source, a nitrogen pipeline and a nitrogen gas seal valve, the nitrogen gas source is communicated with the tail gas pipeline through the nitrogen pipeline, and the nitrogen gas seal valve is arranged on the nitrogen pipeline; and the nitrogen gas source is also communicated with the inlet of the active coke production device.

[0008] In some embodiments, the tail gas treatment system further comprises an air source, an oxygen supplement pipeline and an oxygen supplement quick switch valve, the air source is communicated with the tail gas pipeline through the oxygen supplement pipeline, and the oxygen supplement quick switch valve is arranged on the oxygen supplement pipeline.

[0009] In some embodiments, the tail gas treatment system further comprises a second bypass and a tail gas quick switch valve, the inlet of the second bypass is communicated with the tail gas pipeline, the outlet of the second bypass is communicated with the inlet of the water seal tank, and the tail gas quick switch valve is arranged on the tail gas pipeline between the inlet of the second bypass and the combustion furnace.

[0010] In some embodiments, the outlet of the combustion furnace is connected with a high-temperature fan, a pressure sensor for monitoring the pressure change in the furnace in real time is arranged in the combustion furnace, and the high-temperature fan, the pressure sensor and the tail gas quick switch valve are interlocked.

[0011] In some embodiments, the tail gas treatment system further comprises a blast releasing device comprising a plurality of safety valves and blast releasing sheets, and the safety valves and the blast releasing sheets are arranged on the combustion furnace and the buffer cooling tank.

[0012] In some embodiments, the tail gas treatment system further comprises a flame arrester, and the flame arrester is arranged on the tail gas pipeline close to the inlet of the combustion furnace.

[0013] In some embodiments, the water seal tank further comprises: a water inlet pipe, a water outlet pipe, and a water inlet valve and a water outlet valve arranged on the water inlet pipe and the water outlet pipe respectively.

[0014] In some embodiments, the filter screen is a double-layer metal filter screen.

[0015] In some embodiments, the activated coke production device is a carbonization and activation integrated furnace; and / or,

[0016] The bottom of the combustion furnace is provided with an ash discharge port.

[0017] Compared with the prior art, the utility model has the following beneficial effects:

[0018] 1. The tail gas treatment system provided by the utility model is equipped with a first bypass and a water seal tank to realize pressure relief function. Once the pressure rises due to, for example, filter screen blockage, the tail gas will be guided to the water seal tank through the first bypass and discharged safely from the system;

[0019] 2. The tail gas treatment system provided by the utility model is further equipped with a nitrogen purging device. Nitrogen is purged before carbonization and after activation in the carbonization and activation integrated furnace to ensure that there is no residual combustible gas in the system, thereby improving the safety of the system;

[0020] 3. The tail gas treatment system is further equipped with an interlocking control system. The system can automatically coordinate the actions of the high-temperature fan, the tail gas quick switching valve, the oxygen supplement quick switching valve and the nitrogen sealing valve according to the pressure in the combustion furnace. Once it is detected that the pressure in the combustion furnace exceeds the safe range, the system will automatically close the tail gas quick switching valve and the oxygen supplement quick switching valve, interrupt the oxygen supply, and guide the tail gas to enter the water seal tank through the second bypass, thereby discharging the system. At the same time, the nitrogen sealing valve is started to purify the pipeline and the combustion furnace with nitrogen, so as to ensure that the residual combustible gas is removed from the system;

[0021] 4. The tail gas treatment system is further equipped with a flame arrester, a safety valve and a pressure relief sheet to enhance the safety protection of the pipeline and the equipment, further ensure the stable operation of the system, and prevent accidents;

[0022] 5. The tail gas treatment system provided by the utility model has excellent safety performance and convenient maintenance characteristics. The activated coke production device integrates carbonization and activation functions in the integrated furnace. The closed hearth design effectively reduces heat loss and avoids environmental pollution, thereby realizing the dual benefits of energy saving and environmental protection. BRIEF DESCRIPTION OF DRAWINGS

[0023] The utility model will be further described below in combination with the drawings and examples.

[0024] Figure 1 The structure schematic view of the tail gas treatment system provided by the utility model.

[0025] The meanings of the reference symbols in the drawings are as follows:

[0026] 1 - active coke production device; 2 - buffer cooling tank; 201 - filter screen; 3 - tail gas pipeline; 4 - water seal tank; 401 - emptying port; 402 - water inlet valve; 403 - water outlet valve; 5 - first bypass; 6 - second bypass; 7 - tail gas quick switching valve; 8 - flame arrester; 9 - combustion furnace; 901 - ash discharge port; 10 - high-temperature fan; 11 - nitrogen pipeline; 111 - nitrogen gas sealing valve; 12 - oxygen supplement pipeline; 121 - oxygen supplement quick switching valve;

[0027] 13 - safety valve; 14 - explosion venting sheet. DETAILED DESCRIPTION

[0028] The utility model will be explained in further detail below in combination with the drawings and the description of specific embodiments, but the description below including the embodiments is only used to make the ordinary technicians in the technical field to which the utility model belongs more clearly understand the principle and essence of the utility model, and does not mean to limit the utility model in any form.

[0029] As Figure 1 shown, the embodiment provides a tail gas treatment system for active coke production process, including cooling and decoking device, tail gas pipeline 3, water seal tank 4 and combustion furnace 9, wherein, cooling and decoking device includes buffer cooling tank 2 and filter screen 201, filter screen 201 is arranged in buffer cooling tank 2, the inlet of buffer cooling tank 2 is communicated with the tail gas outlet of active coke production device 1, the outlet of buffer cooling tank 2 is communicated with combustion furnace 9 through tail gas pipeline 3, the tail gas produced in active coke production device 1 enters buffer cooling tank 2 and is cooled, and the tar carried by the tail gas is filtered and removed through filter screen 201, and then enters combustion furnace 9 and is burned, and the combustion furnace 9 provided by the utility model adopts electric heating combustion method.

[0030] Further, buffer cooling tank 2 is further provided with temperature measuring point T, which detects the temperature in buffer cooling tank 2 in real time, to ensure that the temperature is less than 350 DEG C, which is lower than the tar condensation temperature.

[0031] Preferably, the filter screen 201 is a double-layer metal filter screen 201, which is designed to first coarsely filter and then finely filter, so as to effectively and completely remove the tar in the tail gas.

[0032] The water seal tank 4 contains a certain height of water, the inlet of the water seal tank 4 is communicated with the tail gas outlet of the active coke production device 1 through the first bypass 5, a gas inlet pipeline extending below the liquid level in the water seal tank 4 is connected at the inlet of the water seal tank 4, and the top of the water seal tank 4 is provided with a vent 401; when the pressure of the tail gas discharged from the active coke production device 1 is higher than the water seal pressure, such as when the filter screen 201 is blocked by tar, the tail gas enters the water seal tank 4 from the first bypass 5 and is discharged through the vent 401 at the top.

[0033] Further, the water seal tank 4 further comprises a water inlet pipe and a water outlet pipe, and a water inlet valve 402 and a water outlet valve 403 are respectively arranged on the water inlet pipe and the water outlet pipe, and the water inlet valve 402 and the water outlet valve 403 control the water inlet and water outlet processes of the water seal tank 4.

[0034] Preferably, the active coke production device 1 is a carbonization and activation integrated furnace, various coal powders are mixed, kneaded and extruded into a molding material, the molding material is sent into the carbonization and activation integrated furnace, carbonization and activation are integratedly performed under different process temperature conditions, and the tail gas generated in the heating process directly enters the buffer cooling tank 2 for cooling and decoking.

[0035] More preferably, the combustion furnace 9 is provided with a reaction pipe, the tail gas is combusted in the reaction pipe, and the bottom of the combustion furnace 9 is provided with an ash discharge port 901 for periodically discharging the dust and impurities accumulated in the furnace.

[0036] In some embodiments, the tail gas treatment system further comprises an air source, an oxygen supplement pipeline 12 and an oxygen supplement quick switch valve 121, the oxygen supplement quick switch valve 121 is arranged on the oxygen supplement pipeline 12, the air source is communicated with the tail gas pipeline 3 through the oxygen supplement pipeline 12, the air source inputs air (oxygen) into the tail gas pipeline 3, the air (oxygen) is mixed with the tail gas after cooling and decoking, and then the mixture enters the combustion furnace 9 for combustion.

[0037] In some embodiments, the tail gas treatment system further comprises a second bypass 6 and a tail gas quick switch valve 7, the inlet of the second bypass 6 is communicated with the tail gas pipeline 3, and the outlet of the second bypass 6 is communicated with the inlet of the water seal tank 4.

[0038] The tail gas quick cut valve 7 is located on the tail gas pipeline 3 between the inlet of the second bypass 6 and the combustion furnace 9. The combustion furnace 9 is equipped with a pressure sensor for monitoring the pressure change in the furnace in real time. To improve the accuracy and efficiency of monitoring, it is more desirable to directly detect the pressure in the internal reaction tube. Such an arrangement can more directly and accurately capture the pressure change in the reaction process, thereby providing reliable data support for the safe operation of the system. The pressure sensor is interlocked with the tail gas quick cut valve 7. When the pressure in the combustion furnace 9 is greater than the set pressure, the tail gas quick cut valve 7 is automatically cut off, and the tail gas in the tail gas pipeline 3 is guided to the water seal tank 4 through the second bypass 6 and finally discharged from the system, thereby preventing the pressure from further rising due to the continuous passage of tail gas and ensuring the safe operation of the system.

[0039] Further, the tail gas treatment system further comprises a nitrogen purging device for purging the tail gas treatment system, specifically comprising a nitrogen gas source, a nitrogen pipeline 11 and a nitrogen gas seal valve 111.

[0040] On the one hand, the nitrogen gas source also communicates with the inlet of the activated coke production device 1. Before the carbonization process and after the activation process, the activated coke production device 1 and the devices and pipelines downstream thereof are purged with nitrogen to ensure that the system is free of residual combustible gas and improve the safety of the system.

[0041] On the other hand, the nitrogen gas source communicates with the tail gas pipeline 3 through the nitrogen pipeline 11, and the nitrogen gas seal valve 111 is arranged on the nitrogen pipeline 11. The nitrogen gas seal valve 111 is also interlocked with the pressure sensor on the combustion furnace 9. When the tail gas quick cut valve 7 is cut off, the nitrogen gas seal valve 111 is automatically opened to supply nitrogen to the tail gas pipeline 3 and the combustion furnace 9, discharge the combustible gas remaining in the tail gas pipeline 3 and the combustion furnace 9 from the system, and avoid danger in the combustion furnace 9.

[0042] Further, the outlet of the combustion furnace 9 is connected to the high-temperature fan 10, and the burned tail gas is cooled in the top cavity of the combustion furnace 9 and then discharged from the system through the high-temperature fan 10.

[0043] A set of precise interlocking control systems are established between the high-temperature fan 10, the pressure sensor, the tail gas quick cut valve 7, the oxygen supplement quick cut valve 121 and the nitrogen gas seal valve 111. The following is a detailed description of the interlocking process:

[0044] The inlet pressure of the reaction tube (monitored by the pressure measuring point P of the pressure detector) is interlocked with the frequency converter of the high-temperature fan 10 to maintain the negative pressure state in the reaction tube (usually kept below -200 Pa) by adjusting the operating frequency of the high-temperature fan 10. The interlocking control can be realized by an existing controller, such as a PLC controller or other programmable controller. At the same time, the inlet pressure is also interlocked with the tail gas quick cut valve 7, the oxygen supplement quick cut valve 121 and the nitrogen gas sealing valve 111. Once the operating pressure exceeds the preset interlocking pressure value (usually set to -50 Pa), the system will automatically perform the following operations:

[0045] The tail gas quick cut valve 7 and the oxygen supplement quick cut valve 121 are cut off to ensure that the tail gas is guided to the water seal tank 4 through the second bypass 6 and discharged from the system, and the supply of oxygen is stopped.

[0046] At the same time, the nitrogen gas sealing valve 111 is opened to discharge the combustible gas remaining in the system, thereby avoiding dangerous situations in the combustion furnace 9. This series of automatic interlocking measures ensures the safety and stability of the system.

[0047] In some embodiments, the tail gas treatment system further comprises a flame arrester 8 arranged on the tail gas pipeline 3 near the inlet of the combustion furnace 9, which can prevent the spread of the combustion reaction flame in the combustion furnace 9.

[0048] Preferably, along the flow direction of the tail gas, the configuration order of the components and pipelines on the tail gas pipeline 3 is as follows: first the inlet of the second bypass 6, then in turn the tail gas quick cut valve 7, the inlet of the nitrogen pipeline 11, the inlet of the oxygen supplement pipeline 12, the flame arrester 8 and the inlet of the combustion furnace 9. This arrangement can effectively ensure the smoothness and safety of the tail gas treatment process.

[0049] In some embodiments, the tail gas treatment system further comprises a pressure relief device, including a plurality of safety valves 13 and pressure relief sheets 14, which are arranged on the combustion furnace 9 and the buffer cooling tank 2. The safety valve 13 can automatically open to release excess pressure when the device reaches the preset pressure value, and close when the pressure decreases to a safe level. It is suitable for systems that continuously monitor and control pressure, which can prevent damage to the device caused by overpressure. The pressure relief sheet 14 can release pressure when the pressure in the combustion furnace 9 or the buffer cooling tank 2 suddenly increases. It should be noted that the number of safety valves 13 and pressure relief sheets 14 installed in the combustion furnace 9 and the buffer cooling tank 2 is not fixed and can be increased according to actual safety needs to further enhance the safety protection capability of the system.

[0050] In summary, the operation process of the tail gas treatment system is as follows:

[0051] The outlet pipeline of the active coke production device 1 preliminarily cools the tail gas, and after preliminary cooling, the tail gas enters the buffer cooling tank 2 for cooling, and the double-layer filter screen 201 in the tank first coarsely filters and then finely filters to completely remove the tar, and after mixing with oxygen introduced from an air source, the tail gas is introduced into the combustion furnace 9 through the tail gas pipeline 3 for combustion.

[0052] To prevent the safety risk of the tail gas treatment system in operation, the utility model designs three sets of protective measures, first, through the first bypass 5 to release pressure, when the pressure in the pipeline rises, such as the filter screen 201 is blocked to cause the tail gas pressure to increase, the tail gas is introduced into the water seal tank 4 through the first bypass 5 and finally discharged from the system, second, the interlocking control system is implemented, which relates to the interlocking control of the high-temperature fan 10, the pressure sensor, the tail gas quick switching valve 7, the oxygen supplement quick switching valve 121 and the nitrogen gas sealing valve 111, and the specific control process is as described above, third, the flame arrester 8 is installed on the tail gas pipeline, and the safety valve 13 and the explosion venting sheet 14 are installed on the combustion furnace 9 and the buffer cooling tank 2, so as to further ensure the safety of the system.

[0053] The ideal embodiment of the utility model is inspired, and through the above description, relevant staff can certainly make various changes and modifications without deviating from the technical idea of the utility model.

[0054] The technical scope of the utility model is not limited to the content in the specification, and must be determined according to the scope of claims.

Claims

1. A tail gas treatment system for an active coke production process, characterized by, The tail gas treatment system comprises: a cooling and decoking device, a tail gas pipeline, a water seal tank and a combustion furnace, the cooling and decoking device comprises a buffer cooling tank and a filter screen, the tail gas outlet of the active coke production device is communicated with the inlet of the buffer cooling tank, the outlet of the buffer cooling tank is communicated with the combustion furnace through the tail gas pipeline, the buffer cooling tank is used for cooling the tail gas discharged by the active coke production device, and the filter screen is arranged in the buffer cooling tank and used for removing tar in the tail gas; the inlet of the water seal tank is communicated with the tail gas outlet of the active coke production device through a first bypass, an air inlet pipeline extending below the liquid level in the water seal tank is connected at the inlet of the water seal tank, and a vent is arranged at the top of the water seal tank.

2. The tail gas treatment system according to claim 1, further comprising: a nitrogen purging device for purging the tail gas treatment system, the nitrogen purging device comprises a nitrogen gas source, a nitrogen pipeline and a nitrogen gas seal valve, the nitrogen gas source is communicated with the tail gas pipeline through the nitrogen pipeline, and the nitrogen gas seal valve is arranged on the nitrogen pipeline; the nitrogen gas source is also communicated with the inlet of the active coke production device.

3. The tail gas treatment system according to claim 1, further comprising: an air source, an oxygen supplement pipeline and an oxygen supplement quick switch valve, the air source is communicated with the tail gas pipeline through the oxygen supplement pipeline, and the oxygen supplement quick switch valve is arranged on the oxygen supplement pipeline.

4. The tail gas treatment system according to any one of claims 1-3, further comprising: a second bypass and a tail gas quick switch valve, the inlet of the second bypass is communicated with the tail gas pipeline, and the outlet of the second bypass is communicated with the inlet of the water seal tank; the tail gas quick switch valve is arranged on the tail gas pipeline between the inlet of the second bypass and the combustion furnace.

5. The tail gas treatment system according to claim 4, wherein: the outlet of the combustion furnace is connected with a high-temperature fan, a pressure sensor for monitoring the pressure change in the combustion furnace in real time is arranged in the combustion furnace, the high-temperature fan, the pressure sensor and the tail gas quick switch valve are interlocked.

6. The tail gas treatment system according to claim 1, further comprising: an explosion relief device comprising a plurality of safety valves and explosion relief sheets, the safety valves and the explosion relief sheets are arranged on the combustion furnace and the buffer cooling tank.

7. The tail gas treatment system according to claim 1, further comprising: a flame arrester, the flame arrester is arranged on the tail gas pipeline close to the inlet of the combustion furnace.

8. The tail gas treatment system according to claim 1, wherein: the water seal tank further comprises an inlet water pipe, an outlet water pipe, and an inlet water valve and an outlet water valve arranged on the inlet water pipe and the outlet water pipe respectively.

9. The tail gas treatment system according to claim 1, wherein: the filter screen is a double-layer metal filter screen.

10. The tail gas treatment system according to claim 1, wherein: the active coke production device is a carbonization and activation integrated furnace; and / or a dust discharge port is arranged at the bottom of the combustion furnace. ​ ​ ​

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