Dry quenching hot standby system and hot standby method thereof

Abstract

This invention discloses a dry quenching coke hot standby system and its hot standby method, relating to the field of dry quenching coke technology. It includes: a first dry quenching processing unit in operation and a second dry quenching processing unit in standby mode. A first vent pipe of several first dry quenching processing units is connected to a first manifold. The first manifold is connected to the bottom of the dry quenching oven cooling chamber of the second dry quenching processing unit. The top of the cooling chamber of the second dry quenching processing unit is connected to a second induced draft fan. The system utilizes the vent gas generated by the normally operating first dry quenching processing unit as a heat source to provide warm air drying gas to the standby second dry quenching processing unit. This vent gas can also be used as cooling gas for the standby second dry quenching processing unit. This not only allows the standby second dry quenching processing unit to complete warm air drying without other heat sources, saving energy, but also maintains the second dry quenching processing unit in a long-term hot standby state by adding an appropriate amount of red-hot coke.

Description

Technical Field

[0001] This invention relates to the field of dry quenching technology, and in particular to a dry quenching hot standby system and its hot standby method. Background Technology

[0002] Dry quenching, as an important measure for energy conservation and emission reduction in the coking industry, is receiving increasing attention from governments and enterprises. Conventional dry quenching includes a dry quenching oven and a gas circulation structure, utilizing circulating gas to continuously cool the red-hot coke entering the oven. For example, the dry quenching process device disclosed in the invention patent application number "202210437950.5," entitled "A Dry Quenching Process Device for Producing Gasified Coke," is relevant. To ensure the normal operation of the coke oven, a backup dry quenching unit is required. After the backup dry quenching unit is built, how to promptly switch between the operational and backup units becomes a crucial issue. Taking a site with three dry quenching units as an example, if all three dry quenching units are operating simultaneously as hot standby units, each dry quenching system can only reach 67% of its design load, leaving the boiler system under low load, which is detrimental to boiler operation. If the dry quenching units are operated in a 2-on-1 standby configuration (two units in operation and one in cold standby), the two operating units will be at full load, which is also detrimental to the dry quenching system. Moreover, if one operating dry quenching unit malfunctions and the standby unit is required to be put into operation, the heating rate must be controlled at approximately 100 degrees Celsius per day during the furnace drying process, as the inner wall of the dry quenching furnace is constructed of refractory material. Otherwise, the refractory material may crack, affecting the service life of the dry quenching furnace. Furthermore, the refractory material needs to be heated to over 600 degrees Celsius to reach normal operating conditions. Therefore, when the standby dry quenching unit, which is at the same temperature as the external environment, is switched to operation, it takes at least 5 days, severely impacting coke oven production.

[0003] Therefore, there is an urgent need for a dry quenching coke hot standby system that can quickly switch from hot standby to operational status, reduce the impact on coke oven production, improve dry quenching efficiency, and save energy. Summary of the Invention

[0004] The purpose of this invention is to provide a dry quenching hot standby system and method to solve the problems existing in the prior art. It utilizes the vent gas generated by the normally operating first dry quenching unit as a heat source to provide warm air drying gas for the standby second dry quenching unit, eliminating the need for other heat sources to supply heat to the second dry quenching unit, thus saving energy. Furthermore, the vent gas can also be used as cooling gas for the standby second dry quenching unit, keeping the standby second dry quenching unit in a hot standby state, reducing the time required to switch from standby to operational status, and improving dry quenching efficiency.

[0005] To achieve the above objectives, the present invention provides the following solution: The present invention provides a dry quenching coke hot standby system, including a plurality of normally operating first dry quenching coke processing units and at least one standby second dry quenching coke processing unit. The first venting pipes of the plurality of first dry quenching coke processing units are all connected to the bottom of the dry quenching coke oven cooling chamber of the second dry quenching coke processing unit. The top of the cooling chamber of the second dry quenching coke processing unit is connected to a second induced draft fan for drawing out the venting gas from the dry quenching coke oven during the hot standby stage.

[0006] Preferably, both the first dry quenching coke processing unit and the second dry quenching coke processing unit include a dry quenching coke oven and a gas circulation structure. The gas circulation structure includes a primary dust collector, a heat exchange boiler, a secondary dust collector, a circulating fan, and a heat pipe heat exchanger connected in sequence. The air inlet of the primary dust collector is connected to the top of the cooling chamber of the dry quenching coke oven, the air outlet of the heat pipe heat exchanger is connected to the bottom of the cooling chamber of the dry quenching coke oven, and the heat pipe heat exchanger is connected to the first venting pipeline.

[0007] Preferably, the first vent pipes of several first dry quenching coke processing units are connected to the first manifold, and the first manifold is connected to the bottom of the dry quenching coke oven cooling chamber through the first vent pipe of the second dry quenching coke processing unit and the heat pipe heat exchanger.

[0008] Preferably, the second induced draft fan is connected to the secondary dust collector of the second dry quenching coke treatment unit.

[0009] Preferably, the heat pipe heat exchanger is further provided with a second venting pipe, and the first venting pipe and the second venting pipe are connected in parallel.

[0010] Preferably, both the first venting pipeline and the outlet of the second induced draft fan are equipped with on / off valves.

[0011] Preferably, the secondary dust collector of the first dry quenching coke treatment unit is connected to a first induced draft fan.

[0012] Preferably, the outlets of the first induced draft fan and the second induced draft fan are both connected to a gas treatment device for desulfurization, denitrification, decarbonization and dehydration of the gas through a second manifold.

[0013] Preferably, the outlet of the gas processing device is connected to a nitrogen tank.

[0014] The present invention also provides a hot standby method for a dry quenching coke hot standby system, comprising the following steps:

[0015] S1: During the warm air drying stage, the first vent pipe of the first dry quenching coke treatment unit is opened, and the vent gas enters the first manifold and flows from the first manifold through the heat pipe heat exchanger into the dry quenching coke oven of the second dry quenching coke treatment unit. It is attracted by the second induced draft fan, and the vent gas passes through the cooling chamber, the primary dust collector, the heat exchange boiler and the secondary dust collector before being discharged. After the discharged vent gas is treated by the gas treatment device, the remaining nitrogen is collected by the nitrogen tank.

[0016] S2: In the red coke oven heating stage, the gas flow path in step S1 remains unchanged, and red coke is intermittently fed into the dry quenching oven of the second dry quenching treatment system to achieve gradual heating of the dry quenching oven.

[0017] The present invention achieves the following technical effects compared to the prior art:

[0018] 1. In this invention, the vent gas generated by the normally operating first dry quenching unit is used as a heat source to provide warm air drying gas for the warm air drying stage of the standby second dry quenching unit. No other heat source is needed to supply heat to the second dry quenching unit, saving energy. Furthermore, the vent gas can also be used as cooling gas for the standby second dry quenching unit, not only keeping the standby unit in a hot standby state, reducing the time required to switch from standby to operational status, but also allowing the standby second dry quenching unit to share some of the workload of the first dry quenching unit, reducing the load on the first dry quenching unit.

[0019] 2. In this invention, a gas processing device and a nitrogen tank are used to realize the recovery and reuse of nitrogen, thereby saving energy. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a system diagram of the dry quenching coke heat standby system of the present invention;

[0022] The components include: 1. First dry quenching unit; 2. Second dry quenching unit; 3. First manifold; 4. Second induced draft fan; 5. Dry quenching oven; 6. Primary dust collector; 7. Heat exchange boiler; 8. Secondary dust collector; 9. Circulating fan; 10. Heat pipe heat exchanger; 11. First venting pipeline; 12. Second venting pipeline; 13. Oven top venting channel; 14. Emergency venting channel; 15. First induced draft fan; 16. Second manifold; 17. Gas treatment device; 18. Nitrogen tank. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] The purpose of this invention is to provide a dry quenching hot standby system and method to solve the problems existing in the prior art. It utilizes the vent gas generated by the normally operating first dry quenching unit as a heat source to provide warm drying air to the standby second dry quenching unit, eliminating the need for other heat sources and saving energy. Furthermore, the vent gas can also be used as cooling air for the standby second dry quenching unit, keeping it in a hot standby state and reducing the time required to switch from standby to operational status.

[0025] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] Please refer to the following: Figure 1 As shown, a dry quenching coke hot standby system is provided, including several normally operating first dry quenching processing units 1 and at least one standby second dry quenching processing unit 2. The first vent pipes 11 of the several first dry quenching processing units 1 are all connected to the bottom of the cooling chamber of the dry quenching oven 5 of the second dry quenching processing unit 2. The top of the cooling chamber of the second dry quenching processing unit 2 is connected to a second induced draft fan 4 for drawing out the vent gas from the dry quenching oven 5 during the hot standby stage, transferring the vent gas from the first dry quenching processing units 1 in the operating state to the second dry quenching processing unit 2 in the standby state. The second induced draft fan 4 draws out the vent gas after passing through the dry quenching oven 5. The exhaust gas generated by the normally operating first dry quenching unit 1 is used as a heat source to provide warm air drying gas for the warm air drying stage of the standby second dry quenching unit 2. No other heat source is needed to supply heat to the second dry quenching unit 2, saving energy. In addition, the exhaust gas can also be used as the cooling gas for the standby second dry quenching unit 2, so that the standby second dry quenching unit 2 is in a hot standby state, which reduces the time required to switch from standby to operation and improves the dry quenching efficiency. Furthermore, the second dry quenching unit 2 in the hot standby state can share some of the work of the first dry quenching unit 1, reducing the load on the first dry quenching unit 1.

[0027] Both the first dry quenching unit 1 and the second dry quenching unit 2 include a dry quenching oven 5 and a gas circulation structure. The gas circulation structure includes a primary dust collector 6, a heat exchange boiler 7, a secondary dust collector 8, a circulating fan 9, and a heat pipe heat exchanger 10 connected in sequence. The heat exchange boiler 7 and the heat pipe heat exchanger 10 are used to cool the vented gas. The top of the cooling chamber of the dry quenching oven is provided with several annularly distributed inclined channels, the two ends of which are connected to the cooling chamber and the annular flue, respectively. The air inlet of the primary dust collector 6 is connected to the annular flue of the dry quenching oven 5. The flue is connected, and the outlet of the heat pipe heat exchanger 10 is connected to the bottom of the cooling chamber of the dry quenching coke oven 5. The heat pipe heat exchanger 10 is connected to the first venting pipe 11, which is the pressure regulating pipe of the pre-storage chamber. The venting gas flowing out of the first venting pipe 11 is the cooled gas, maintained at about 120°C. This gas can raise the temperature of the dry quenching coke oven 5 of the second dry quenching coke treatment unit 2 to above 110°C. The heat exchange boiler 7, heat pipe heat exchanger 10 and circulating fan 9 are not started in the standby state.

[0028] The first vent pipes 11 of several first dry quenching coke processing units 1 are connected to the first manifold 3. The first manifold 3 is connected to the bottom of the cooling chamber of the dry quenching coke oven 5 through the first vent pipes 11 of the second dry quenching coke processing unit 2 and the heat pipe heat exchanger 10, which reduces the addition of unnecessary pipes and eliminates the need to open additional through holes on the dry quenching coke oven 5.

[0029] The second induced draft fan 4 is connected to the secondary dust collector 8 of the second dry quenching coke treatment unit 2. This not only reduces the step of drilling holes in the dry quenching coke oven 5 to install pipes to connect the second induced draft fan 4, but also allows the drawn gas to pass through the primary dust collector 6 and the secondary dust collector 8, reducing environmental pollution. In order to ensure that the vent gas moves along the path of heat pipe heat exchanger 10, dry quenching coke oven 5, primary dust collector 6, heat exchange boiler 7 and secondary dust collector 8 under this condition, a one-way valve is installed between the circulating fan 9 and the heat pipe heat exchanger 10. In order to ensure that outside air does not enter the gas circulation structure when the second induced draft fan 4 is turned off, the second induced draft fan 4 is selected as a Roots blower that plays a sealing role when not in operation, or a one-way valve is installed in the connecting pipe between the second induced draft fan 4 and the secondary dust collector 8.

[0030] The heat pipe heat exchanger 10 is also provided with a second venting pipe 12. The first venting pipe 11 and the second venting pipe 12 are connected in parallel. The second venting pipe 12 is connected to an external exhaust treatment device or other thermal energy application equipment. However, when a large amount of venting gas is generated, a portion can be released through the second venting pipe 12, and the other portion can be used as a heat source for the second dry quenching treatment unit 2 as a backup.

[0031] Both the first venting pipeline 11 and the second venting pipeline 12 are equipped with on / off valves, preferably electrically controlled valves, to control the emission of vented gas.

[0032] The top of the dry quenching oven 5 of the first dry quenching unit 1 and the second dry quenching unit 2 is also provided with a furnace top venting pipe 13 for venting gas. An emergency venting pipe 14 is provided on the primary dust collector 6. Both the furnace top venting pipe 13 and the emergency venting pipe 14 are equipped with electrically controlled valves.

[0033] Since both the first dry quenching unit 1 and the second dry quenching unit 2 will undergo status switching during subsequent actual use, i.e., from standby to operation and from operation to standby, the secondary dust collector 8 of the first dry quenching unit 1 is connected to the first induced draft fan 15. The function of the first induced draft fan 15 is the same as that of the second induced draft fan 4. When the dry quenching unit where the first induced draft fan 15 is located is switched from operation to standby, it can be used.

[0034] The outlets of the first induced draft fan 15 and the second induced draft fan 4 are both connected to the gas treatment device 17, which is used to desulfurize, denitrify, decarbonize and dehydrate the gas, through the second manifold 16. The gas treatment device 17 has multiple compartments for desulfurization, denitrification, decarbonization and dehydration of the gas, respectively. In addition, the second vent pipe 12 of both the first dry quenching unit 1 and the second dry quenching unit 2 can be connected to the gas treatment device 17.

[0035] The outlet of the gas processing device 17 is connected to the nitrogen tank 18 to realize the recovery and reuse of nitrogen and save energy.

[0036] The present invention also provides a hot standby method for a dry quenching coke hot standby system, comprising the following steps:

[0037] S1: In the warm air drying stage of the standby second dry quenching coke treatment unit 2, the first vent pipe 11 of the first dry quenching coke treatment unit 1 is opened, the vent gas enters the first collector pipe 3, and flows from the first collector pipe 3 through the heat pipe heat exchanger 10 into the dry quenching oven 5 of the second dry quenching coke treatment unit 2. It is attracted by the second induced draft fan 4, and the vent gas passes through the cooling chamber, inclined duct, annular flue, primary dust collector 6, heat exchange boiler 7 and secondary dust collector 8 before being discharged. After the discharged vent gas is treated by the gas treatment device 17, the remaining nitrogen is collected by the nitrogen tank 18.

[0038] S2: In the red coke oven baking stage of the standby second dry quenching coke treatment unit 2, the venting gas flow path in step S1 remains unchanged, and red coke is intermittently added to the dry quenching coke oven 5 of the second dry quenching coke treatment system. In the initial stage, red coke can be added in small amounts and multiple times. Subsequently, the addition interval is gradually reduced to achieve gradual heating of the dry quenching coke oven 5. Finally, by adjusting the amount of red coke and the addition interval (the amount of red coke added and the addition interval need to be determined according to the flow rate and temperature of the venting gas), the temperature of the dry quenching coke oven 5 is stabilized, and the hot standby is completed.

[0039] After completing the hot standby using the above method, when it is necessary to switch from hot standby to operational status, shut down the second induced draft fan 4 and the first vent pipe 11, turn on the circulating fan 9, heat exchange boiler 7 and heat pipe heat exchanger 10 of the second dry quenching coke treatment unit 2, and inject nitrogen into the second dry quenching coke treatment unit 2. The injection method is as follows: inject through the air inlet valve on the top of the dry quenching coke oven 5 (the air inlet valve is not only used for nitrogen injection, but also for introducing outside air into the dry quenching coke oven 5 during normal use, in conjunction with the temperature of the red coke to treat the volatilized CO and H2, etc.). After the nitrogen injection is completed, red coke can be intermittently added again until the temperature of the dry quenching coke oven 5 rises to the normal operating conditions, and then the operation switch is completed and it can enter the normal operating state.

[0040] Any adaptive changes made according to actual needs are within the scope of protection of this invention.

[0041] It should be noted that, for those skilled in the art, it is obvious that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0042] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A dry quenching coke heat backup system, characterized in that, It includes several normally operating first dry quenching coke processing units and at least one standby second dry quenching coke processing unit. The first venting pipes of the several first dry quenching coke processing units are all connected to the bottom of the dry quenching coke oven cooling chamber of the second dry quenching coke processing unit. The top of the cooling chamber of the second dry quenching coke processing unit is connected to a second induced draft fan for drawing out the venting gas in the dry quenching coke oven during the hot standby stage. The first vent pipes of several first dry quenching coke treatment units are connected to the first manifold. The first manifold is connected to the bottom of the dry quenching coke oven cooling chamber through the first vent pipe of the second dry quenching coke treatment unit and the heat pipe heat exchanger. The second induced draft fan is connected to the secondary dust collector of the second dry quenching coke treatment unit. In the first dry quenching coke processing unit and the second dry quenching coke processing unit, the top of the cooling chamber of the dry quenching coke oven is provided with several annularly distributed inclined channels. The two ends of the inclined channels are respectively connected to the cooling chamber and the annular flue. The air inlet of the primary dust collector is connected to the annular flue of the dry quenching coke oven. Both the first dry quenching coke processing unit and the second dry quenching coke processing unit include a dry quenching coke oven and a gas circulation structure. The gas circulation structure includes a primary dust collector, a heat exchange boiler, a secondary dust collector, a circulating fan, and a heat pipe heat exchanger connected in sequence. The air inlet of the primary dust collector is connected to the top of the cooling chamber of the dry quenching coke oven, and the air outlet of the heat pipe heat exchanger is connected to the bottom of the cooling chamber of the dry quenching coke oven. The heat pipe heat exchanger is connected to the first venting pipeline, and the venting gas flowing out of the first venting pipeline is the cooled gas.

2. The dry quenching coke hot standby system according to claim 1, characterized in that, The heat pipe heat exchanger is also provided with a second venting pipe, and the first venting pipe and the second venting pipe are connected in parallel.

3. The dry quenching coke hot standby system according to claim 2, characterized in that, Both the first venting pipeline and the second venting pipeline are equipped with on / off valves.

4. The dry quenching coke hot standby system according to any one of claims 1-3, characterized in that, The secondary dust collector of the first dry quenching coke treatment unit is connected to the first induced draft fan.

5. The dry quenching coke hot standby system according to claim 4, characterized in that, The outlets of both the first and second induced draft fans are connected to a gas treatment device for desulfurization, denitrification, decarbonization, and dehydration of the gas via a second manifold.

6. The dry quenching coke hot standby system according to claim 5, characterized in that, The outlet of the gas processing device is connected to a nitrogen tank.

7. A hot standby method using the dry quenching coke hot standby system according to any one of claims 1-6, characterized in that, Includes the following steps: S1: During the warm air drying stage, the first vent pipe of the first dry quenching coke treatment unit is opened, and the vent gas enters the first manifold and flows from the first manifold through the heat pipe heat exchanger into the dry quenching coke oven of the second dry quenching coke treatment unit. It is attracted by the second induced draft fan, and the vent gas passes through the cooling chamber, the primary dust collector, the heat exchange boiler and the secondary dust collector before being discharged. After the discharged vent gas is treated by the gas treatment device, the remaining nitrogen is collected by the nitrogen tank. S2: In the red coke oven heating stage, the gas flow path in step S1 remains unchanged, and red coke is intermittently fed into the dry quenching oven of the second dry quenching treatment system to achieve gradual heating of the dry quenching oven.

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