Dry quenching system and process

Abstract

The dry quenching system comprises a dry quenching furnace and a vertical external heating type pyrolyzing furnace, an annular flue of the dry quenching furnace is communicated with a combustion chamber of the pyrolyzing furnace, a flue gas outlet of the combustion chamber is sequentially connected with a primary dust remover, a primary air heat exchanger, a secondary dust remover, a secondary air heat exchanger and a circulating fan, and an outlet of the circulating fan is divided into two paths, the diffusion gas path is divided into two paths, one path is connected with a decarburization device, the other path is connected with a positive pressure gas protection cavity outside the pyrolyzing furnace, a carbon dioxide outlet of the decarburization device is connected with the bottom of a carbonization chamber through a carbon dioxide fan, and the top of the carbonization chamber is connected with a purification system through a gas collecting pipe; an air outlet of the primary air heat exchanger is connected with the combustion chamber, and an air outlet of the secondary air heat exchanger is connected with the low-rank coal hot air dehydration device. According to the invention, the dry quenching furnace is coupled with the vertical externally-heated pyrolyzing furnace, so that the heat of the red coke is comprehensively and efficiently utilized, the production operation is simplified, and water, energy and investment are saved.

Description

Technical Field

[0001] The present invention relates to the technical field of coke dry quenching, and in particular to a coke dry quenching system and process. Background Art

[0002] Coke dry quenching, referred to as CDQ, is the use of inert gas (nitrogen) and high-temperature coke (red coke) in the CDQ oven for heat exchange. The coke is cooled to a qualified temperature (less than 180°C) and discharged. The inert gas (nitrogen) is heated to a high temperature and sent to the waste heat boiler for heat exchange with demineralized water. The inert gas is cooled to 160°C and discharged from the boiler to the circulating fan. The inert gas is blown into the CDQ oven for countercurrent contact and heat exchange with the red coke. The demineralized water is heated to high-temperature and high-pressure steam, and the steam is sent to the steam turbine to generate power. In this cycle, the heat of the red coke is transferred to the steam to generate power, and the coke temperature drops from 1050°C to 180°C. The above process has been used since the development of CDQ technology for nearly half a century. The current technical development direction of CDQ is still based on the above process principle, and work is carried out in aspects such as large-scale processing capacity, without in-depth research on this process.

[0003] However, the above technical process has the following problems: 1. The heat of red coke is used to generate electricity through steam, and the energy utilization efficiency is not high; 2. Frequent accidents of waste heat boilers affect the normal production of dry quenching coke ovens; 3. Waste heat boilers and steam turbine generators are production equipment that are subject to mandatory national inspections and require qualified personnel to operate them, which makes it difficult to train talents for traditional coking enterprises; 4. Affected by the boiler material, etc., the circulating gas temperature at the boiler inlet generally cannot exceed 1050°C; 5. The boiler needs to be supplemented with desalted water and circulating cooling water, which consumes a lot of water and faces great problems in water-scarce areas; 6. The combustible components in the circulating gas burn at the outlet of the chute and in the annular flue, causing thermal stress on the annular flue, affecting the stability of the annular flue structure and its service life; 7. The high-temperature coke particles contained in the circulating gas out of the chute are removed in a primary dust collector, discharged after cooling, and used as fuel, which is a poor way of energy utilization.

[0004] In view of this, we propose a new dry quenching system and process, which eliminates the drawbacks of using waste heat boilers and steam turbines for dry quenching production, fully and efficiently utilizes the heat of red coke, simplifies production operations, saves water and energy, and saves investment. Summary of the invention

[0005] The purpose of the present invention is to provide a coke dry quenching system and process to solve the problems existing in the above-mentioned prior art, couple the coke dry quenching furnace with the vertical external heating pyrolysis furnace, eliminate the disadvantages of using waste heat boilers and steam turbines for coke dry quenching production, fully and efficiently utilize the heat of red coke, simplify production operations, save water and energy, and save investment.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a dry quenching system, comprising a dry quenching furnace and a vertical externally heated pyrolysis furnace, wherein the annular flue of the dry quenching furnace is connected to the combustion chamber of the pyrolysis furnace, the flue gas outlet of the combustion chamber of the pyrolysis furnace is sequentially connected to a primary dust collector, a primary air heat exchanger, a secondary dust collector, a secondary air heat exchanger and a circulating fan, the outlet of the circulating fan is divided into two paths, one of which is connected to a venting air path, and the other is connected to the upper and lower air chambers of the dry quenching furnace, the venting air path is divided into two paths, one of which is connected to a decarbonization device, and the other is connected to a positive pressure air outlet outside the pyrolysis furnace. The carbon dioxide outlet of the decarbonization device is connected to a carbon dioxide blower, the air outlet of the carbon dioxide blower is connected to the bottom of the carbonization chamber in the pyrolysis furnace, the top of the carbonization chamber is connected to the purification system through an air collecting pipe, the air inlet of the primary air heat exchanger is connected to the first air blower, the air outlet of the primary air heat exchanger is connected to the combustion chamber of the pyrolysis furnace, the air inlet of the secondary air heat exchanger is connected to the second air blower, and the air outlet of the secondary air heat exchanger is connected to a low-rank coal hot air dehydration device.

[0008] In one embodiment, the primary dust collector is a cyclone dust collector or an inertial dust collector.

[0009] In one embodiment, the secondary dust collector is a bag dust collector or a cyclone dust collector.

[0010] In one embodiment, an air channel is provided in the combustion chamber of the pyrolysis furnace, the upper end of the air channel extends to the top of the combustion chamber of the pyrolysis furnace and is connected to the air outlet of the primary air heat exchanger, and the lower end of the air channel extends to the bottom of the combustion chamber of the pyrolysis furnace and is connected to the combustion chamber of the pyrolysis furnace.

[0011] In one embodiment, the air outlet of the low-rank coal hot air dehydration device is connected to an air condenser.

[0012] In one embodiment, the combustion chamber of the pyrolysis furnace is provided with a desulfurization-decarbonization agent inlet and an ash discharge port.

[0013] The present invention also provides a coke dry quenching process, based on the coke dry quenching system described above, comprising:

[0014] The dry coke quenching circulating gas enters the combustion chamber of the pyrolysis furnace from the annular flue of the dry coke quenching furnace, and in the combustion chamber of the pyrolysis furnace, the combustible gas and coke powder in the dry coke quenching circulating gas are burned to provide heat to the pyrolysis furnace, and then the dry coke quenching circulating gas is discharged from the combustion chamber of the pyrolysis furnace and passes through the primary dust collector, the primary air heat exchanger, the secondary dust collector, the secondary air heat exchanger and the circulating fan in sequence;

[0015] The CDQ circulating gas is divided into two paths after passing through the circulating fan, one path enters the exhaust gas path, and the other path enters the upper and lower air chambers of the CDQ furnace to continue to participate in the cooling process of the red coke in the CDQ furnace, and then circulates through the annular flue of the CDQ furnace into the combustion chamber of the pyrolysis furnace;

[0016] The dry quenched coke emission gas entering the emission gas path is divided into two paths, one path enters the positive pressure gas protection chamber outside the pyrolysis furnace to form positive pressure gas protection for the pyrolysis furnace, and the other path is used for carbon dioxide separation. The separated carbon dioxide is introduced into the bottom of the carbonization chamber in the pyrolysis furnace, and firstly exchanges heat with the semi-coke discharged from the pyrolysis furnace, the carbon dioxide is preheated, and the semi-coke is cooled. Then the preheated carbon dioxide enters the high temperature zone at the lower part of the carbonization chamber, and reacts with the semi-coke to gasify. The generated carbon monoxide rises together with the carbon dioxide and enters the dry distillation zone, preheating zone and drying zone of the carbonization chamber in sequence, and finally is discharged from the carbonization chamber together with the dry distillation gas, and then enters the purification system through the gas collecting pipe for purification treatment;

[0017] The first air blower blows air into the primary air heat exchanger, exchanges heat with the CDQ circulating gas, and then passes air into the combustion chamber of the pyrolysis furnace;

[0018] The second air blower blows air into the secondary air heat exchanger, and after heat exchange with the dry quenching circulating gas, the low-rank coal is heated and dehydrated. The dehydrated low-rank coal is sent to the carbonization chamber of the pyrolysis furnace for pyrolysis and carbonization. The air after heat exchange is condensed and dehydrated and then released, and the condensed water is collected.

[0019] In one embodiment, the primary air heat exchanger preheats the air to 230°C-300°C;

[0020] The secondary air heat exchanger preheats the air to 230°C-280°C, and the CDQ circulating gas is cooled to below 60°C.

[0021] In one embodiment, the low-rank coal is heated and dehydrated to reduce the moisture content of the low-rank coal to below 10%.

[0022] In one embodiment, water vapor is added to the separated carbon dioxide, and then the mixed gas is introduced into the bottom of the carbonization chamber in the pyrolysis furnace, and first heat is exchanged with the semi-coke discharged from the pyrolysis furnace, the carbon dioxide and water vapor are preheated, and the semi-coke is cooled. Thereafter, the preheated carbon dioxide and water vapor enter the high-temperature zone in the lower part of the carbonization chamber, and undergo a gasification reaction with the semi-coke. The generated hydrogen and carbon monoxide rise together with the carbon dioxide and water vapor and enter the distillation zone, preheating zone and drying zone of the carbonization chamber in sequence, and finally are discharged from the carbonization chamber together with the distillation gas, and then enter the purification system through the gas collecting pipe for purification treatment.

[0023] Compared with the prior art, the present invention has achieved the following technical effects:

[0024] The dry quenching system and process provided by the present invention couples the dry quenching furnace with a vertical externally heated pyrolysis furnace, transfers the heat of high-temperature coke (red coke) to the heat required for pyrolysis of low-rank coal through the dry quenching circulating gas, eliminates the disadvantages of using waste heat boilers and steam turbines for dry quenching production, fully and efficiently utilizes the heat of red coke, simplifies production operations, saves water and energy, and saves investment. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 The figure is a flow chart of the dry coke quenching process in an embodiment of the present invention.

[0027] In the figure: 1- dry quenching furnace, 2- pyrolysis furnace, 3- annular flue, 4- primary dust collector, 5- primary air heat exchanger, 6- secondary dust collector, 7- secondary air heat exchanger, 8- circulating fan, 9- decarbonization device, 10- positive pressure gas protection chamber, 11- carbon dioxide fan, 12- first air blower, 13- second air blower, 14- low-grade coal hot air dehydration device, 15- air condenser. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] The purpose of the present invention is to provide a coke dry quenching system and process to solve the problems existing in the prior art, couple the coke dry quenching furnace with a vertical externally heated pyrolysis furnace, fully and efficiently utilize the heat of red coke, simplify production operations, save water and energy, and save investment.

[0030] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] Embodiment 1

[0032] like Figure 1As shown, this embodiment provides a dry quenching system, including a dry quenching furnace 1 and a vertical external heating pyrolysis furnace 2, the vertical external heating pyrolysis furnace 2 is provided with an independent carbonization chamber and a combustion chamber, the annular flue 3 of the dry quenching furnace 1 is connected to the combustion chamber of the pyrolysis furnace 2, the flue gas outlet of the combustion chamber of the pyrolysis furnace 2 is connected to a primary dust collector 4, a primary air heat exchanger 5, a secondary dust collector 6, a secondary air heat exchanger 7 and a circulating fan 8 in sequence, the outlet of the circulating fan 8 is divided into two paths, one is connected to the emission gas path, and the other is connected to the upper and lower air chambers of the dry quenching furnace 1, the emission gas path is divided into two paths, one is connected to the decarbonization device 9, and the other is connected to the positive pressure gas protection chamber 10 outside the pyrolysis furnace 2, The carbon dioxide outlet of the decarbonization device 9 is connected to the carbon dioxide fan 11, the outlet of the carbon dioxide fan 11 is connected to the bottom of the carbonization chamber in the pyrolysis furnace 2, the top of the carbonization chamber is connected to the purification system through the air collecting pipe, the air inlet of the primary air heat exchanger 5 is connected to the first air blower 12, the air outlet of the primary air heat exchanger 5 is connected to the combustion chamber of the pyrolysis furnace 2, the air inlet of the secondary air heat exchanger 7 is connected to the second air blower 13, and the air outlet of the secondary air heat exchanger 7 is connected to the low-rank coal hot air dehydration device 14, which is used to heat and dehydrate the low-rank coal. The dehydrated low-rank coal is sent to the carbonization chamber of the pyrolysis furnace 2 for pyrolysis and carbonization.

[0033] In this embodiment, the decarbonization device 9 uses the alcohol amine method to separate carbon dioxide. The primary dust collector 4 is a cyclone dust collector or an inertial dust collector. The secondary dust collector 6 is a bag dust collector or a cyclone dust collector.

[0034] In this embodiment, an air passage is provided in the combustion chamber of the pyrolysis furnace 2, the upper end of the air passage extends to the top of the combustion chamber of the pyrolysis furnace 2 and is connected to the air outlet of the primary air heat exchanger 5, and the lower end of the air passage extends to the bottom of the combustion chamber of the pyrolysis furnace 2 and is connected to the combustion chamber of the pyrolysis furnace 2. The air after heat exchange in the primary air heat exchanger 5 enters the air passage in the combustion chamber, is gradually heated during the downward flow in the air passage in the combustion chamber, and is finally ejected from the bottom of the combustion chamber to mix with the combustible gas and coke powder in the dry quenching cycle gas to burn, heat the furnace wall of the carbonization chamber, and indirectly transfer heat to the carbonization chamber.

[0035] In this embodiment, the air outlet of the low-rank coal hot air dehydration device 14 is connected to the air condenser 15. After the air after heat exchange by the secondary air heat exchanger 7 heats and dehydrates the low-rank coal in the low-rank coal hot air dehydration device 14, it is condensed and dehydrated by the air condenser 15, the condensed water is collected, and the dehydrated air is released.

[0036] In this embodiment, the combustion chamber of the pyrolysis furnace 2 is provided with a desulfurization-decarbonization agent inlet and an ash discharge port, so as to add desulfurization agent and decarbonization agent for desulfurization and decarbonization treatment and facilitate the discharge of ash.

[0037] Embodiment 2

[0038] like Figure 1 As shown, this embodiment provides a dry coke quenching process, based on the dry coke quenching system described in Embodiment 1, comprising:

[0039] The CDQ circulating gas enters the combustion chamber of the pyrolysis furnace 2 from the annular flue of the CDQ furnace 1. In the combustion chamber of the pyrolysis furnace 2, the combustible gas and coke powder in the CDQ circulating gas are burned to provide heat to the pyrolysis furnace 2. The air introduction amount is controlled according to the maximum combustion to burn out the combustible gas and coke powder as much as possible. Then the CDQ circulating gas is discharged from the combustion chamber of the pyrolysis furnace 2 and passes through the primary dust collector 4, the primary air heat exchanger 5, the secondary dust collector 6, the secondary air heat exchanger 7 and the circulating fan 8 in sequence.

[0040] The CDQ circulating gas is divided into two paths after passing through the circulating fan 8, one path enters the exhaust gas path, and the other path enters the upper and lower air chambers of the CDQ furnace 1 to continue to participate in the cooling process of the red coke in the CDQ furnace 1, and then circulates through the annular flue 3 of the CDQ furnace 1 into the combustion chamber of the pyrolysis furnace 2;

[0041] The CDQ exhaust gas entering the exhaust gas path is divided into two paths. One path enters the positive pressure gas protection chamber 10 outside the pyrolysis furnace 2 to form positive pressure gas protection for the pyrolysis furnace 2 to prevent air from infiltrating the circulating gas due to cracks in the refractory materials, and the other path uses the alcohol amine method to separate carbon dioxide to obtain carbon dioxide and nitrogen.

[0042] The separated carbon dioxide is introduced into the bottom of the carbonization chamber in the pyrolysis furnace 2, and firstly exchanges heat with the blue char discharged from the pyrolysis furnace 2, the carbon dioxide is preheated, and the blue char is cooled, and then the preheated carbon dioxide enters the high temperature zone in the lower part of the carbonization chamber, and reacts with the semi-coke to gasify, and the generated carbon monoxide rises together with the carbon dioxide and enters the dry distillation zone, preheating zone and drying zone of the carbonization chamber in sequence, and finally is discharged from the carbonization chamber together with the dry distillation gas, and then enters the purification system through the gas collecting pipe for purification treatment;

[0043] Alternatively, part of water vapor is added to the separated carbon dioxide, and then the mixed gas of carbon dioxide and water vapor is introduced into the bottom of the carbonization chamber in the pyrolysis furnace 2, and firstly heat-exchanged with the semi-coke discharged from the pyrolysis furnace 2, the carbon dioxide and water vapor are preheated, and the semi-coke is cooled, and then the preheated carbon dioxide and water vapor enter the high-temperature zone in the lower part of the carbonization chamber, and react with the semi-coke to gasify, and the generated hydrogen and carbon monoxide rise together with the carbon dioxide and water vapor and enter the dry distillation zone, preheating zone and drying zone of the carbonization chamber in turn, and finally are discharged from the carbonization chamber together with the dry distillation gas, and then enter the purification system through the gas collecting pipe for purification treatment;

[0044] The first air blower 12 blows air into the primary air heat exchanger 5, exchanges heat with the CDQ circulating gas, and then passes air into the combustion chamber of the pyrolysis furnace 2; the waste heat of the CDQ circulating gas is further used to preheat the air passing into the combustion chamber;

[0045] The second air blower 13 blows air into the secondary air heat exchanger 7, and after heat exchange with the dry quenching circulating gas, the low-rank coal is heated and dehydrated, and the waste heat of the dry quenching circulating gas is further utilized. The dehydrated low-rank coal is sent to the carbonization chamber of the pyrolysis furnace 2 for pyrolysis and carbonization. The air after heat exchange is condensed and dehydrated and then released, and the condensed water is collected.

[0046] In this process, the combustible gas is introduced into the combustion chamber of the pyrolysis furnace 2 and burned at a temperature greater than 1050°C, generally around 1300°C; the combustible gas burns in the combustion chamber of the pyrolysis furnace 2, avoiding the disadvantages of burning at the chute outlet and in the annular flue, which causes thermal stress on the annular flue and affects the structural stability and service life of the annular flue.

[0047] In this embodiment, the primary air heat exchanger 5 preheats the air to 230°C-300°C;

[0048] The secondary air heat exchanger 7 preheats the air to 230°C-280°C, and the CDQ cycle gas is cooled to below 60°C;

[0049] Generally speaking, the moisture content of low-rank coal is high, about 20-30%, or even higher. This process uses hot air to heat and dehydrate low-rank coal, reducing the moisture content of low-rank coal to below 10%, which is beneficial to reduce the heat required for pyrolysis and reduce the wastewater content in the pyrolysis gas.

[0050] The low-rank coal pyrolysis gas purification technology is basically the same as the conventional coke oven gas purification technology. Therefore, in the present invention, for the dry quenching of conventional coke ovens, the pyrolysis gas of the pyrolysis furnace 2 is directly incorporated into the coke oven raw gas pipeline and treated with the coke oven gas purification technology. The pyrolysis gas is sprayed with ammonia water for cooling, gas-liquid separation, condensation and blasting, desulfurization and other purification units to complete the pyrolysis gas purification. The light tar separated from the pyrolysis gas is distilled to obtain gasoline and diesel. Phenol-containing wastewater is treated to obtain phenol products.

[0051] In the case of dry quenching of coke with heat recovery coke oven, since the heat recovery coke oven does not have a raw gas purification unit, the raw gas of the coke oven is directly introduced into the coke oven combustion chamber to burn and generate high-temperature flue gas, and the heat of the high-temperature flue gas is recovered by the waste heat boiler to generate electricity. Therefore, in this case, a separate purification system needs to be set up for the purification treatment of the pyrolysis gas of the pyrolysis furnace 2. In this purification system, the treatment can be carried out according to the above-mentioned coke oven gas purification technology.

[0052] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A coke dry quenching system, characterized in that: It comprises a dry quenching furnace and a vertical externally heated pyrolysis furnace, wherein the annular flue of the dry quenching furnace is connected to the combustion chamber of the pyrolysis furnace, and the flue gas outlet of the combustion chamber of the pyrolysis furnace is connected to a primary dust collector, a primary air heat exchanger, a secondary dust collector, a secondary air heat exchanger and a circulating fan in sequence, and the outlet of the circulating fan is divided into two paths, one of which is connected to a dissipating air path, and the other is connected to the upper and lower air chambers of the dry quenching furnace, and the dissipating air path is divided into two paths, one of which is connected to a decarbonization device, and the other is connected to a positive pressure gas protection chamber outside the pyrolysis furnace, and the The carbon dioxide outlet of the decarbonization device is connected to a carbon dioxide fan, the air outlet of the carbon dioxide fan is connected to the bottom of the carbonization chamber in the pyrolysis furnace, the top of the carbonization chamber is connected to the purification system through an air collecting pipe, the air inlet of the primary air heat exchanger is connected to a first air blower, the air outlet of the primary air heat exchanger is connected to the combustion chamber of the pyrolysis furnace, the air inlet of the secondary air heat exchanger is connected to a second air blower, and the air outlet of the secondary air heat exchanger is connected to a low-grade coal hot air dehydration device.

2. The dry coke quenching system according to claim 1, characterized in that: The primary dust collector is a cyclone dust collector or an inertial dust collector.

3. The dry coke quenching system according to claim 1, characterized in that: The secondary dust collector is a bag type dust collector or a cyclone dust collector.

4. The dry coke quenching system according to claim 1, characterized in that: An air channel is provided in the combustion chamber of the pyrolysis furnace, the upper end of the air channel extends to the top of the combustion chamber of the pyrolysis furnace and is connected to the air outlet of the primary air heat exchanger, and the lower end of the air channel extends to the bottom of the combustion chamber of the pyrolysis furnace and is connected to the combustion chamber of the pyrolysis furnace.

5. The dry coke quenching system according to claim 1, characterized in that: The air outlet of the low-rank coal hot air dehydration device is connected to an air condenser.

6. The dry coke quenching system according to claim 1, characterized in that: The combustion chamber of the pyrolysis furnace is provided with a desulfurization-decarbonization agent inlet and an ash discharge port.

7. A coke dry quenching process, characterized in that: The dry coke quenching system according to any one of claims 1 to 6 comprises: The dry coke quenching circulating gas enters the combustion chamber of the pyrolysis furnace from the annular flue of the dry coke quenching furnace, and in the combustion chamber of the pyrolysis furnace, the combustible gas and coke powder in the dry coke quenching circulating gas are burned to provide heat to the pyrolysis furnace, and then the dry coke quenching circulating gas is discharged from the combustion chamber of the pyrolysis furnace and passes through the primary dust collector, the primary air heat exchanger, the secondary dust collector, the secondary air heat exchanger and the circulating fan in sequence; The CDQ circulating gas is divided into two paths after passing through the circulating fan, one path enters the exhaust gas path, and the other path enters the upper and lower air chambers of the CDQ furnace to continue to participate in the cooling process of the red coke in the CDQ furnace, and then circulates through the annular flue of the CDQ furnace into the combustion chamber of the pyrolysis furnace; The dry quenched coke emission gas entering the emission gas path is divided into two paths, one path enters the positive pressure gas protection chamber outside the pyrolysis furnace to form positive pressure gas protection for the pyrolysis furnace, and the other path is used for carbon dioxide separation. The separated carbon dioxide is introduced into the bottom of the carbonization chamber in the pyrolysis furnace, and firstly exchanges heat with the semi-coke discharged from the pyrolysis furnace, the carbon dioxide is preheated, and the semi-coke is cooled. Then the preheated carbon dioxide enters the high temperature zone at the lower part of the carbonization chamber, and reacts with the semi-coke to gasify. The generated carbon monoxide rises together with the carbon dioxide and enters the dry distillation zone, preheating zone and drying zone of the carbonization chamber in sequence, and finally is discharged from the carbonization chamber together with the dry distillation gas, and then enters the purification system through the gas collecting pipe for purification treatment; The first air blower blows air into the primary air heat exchanger, exchanges heat with the CDQ circulating gas, and then passes air into the combustion chamber of the pyrolysis furnace; The second air blower blows air into the secondary air heat exchanger, and after heat exchange with the dry quenching circulating gas, the low-rank coal is heated and dehydrated. The dehydrated low-rank coal is sent to the carbonization chamber of the pyrolysis furnace for pyrolysis and carbonization. The air after heat exchange is condensed and dehydrated and then released, and the condensed water is collected.

8. The dry coke quenching process according to claim 7, characterized in that: The primary air heat exchanger preheats the air to 230°C-300°C; The secondary air heat exchanger preheats the air to 230°C-280°C, and the CDQ circulating gas is cooled to below 60°C.

9. The dry coke quenching process according to claim 7, characterized in that: The low-rank coal is heated and dehydrated to reduce its moisture content to below 10%.

10. The dry coke quenching process according to claim 7, characterized in that: Water vapor is added to the separated carbon dioxide, and then the mixed gas is introduced into the bottom of the carbonization chamber in the pyrolysis furnace, and firstly heat-exchanged with the semi-coke discharged from the pyrolysis furnace, the carbon dioxide and water vapor are preheated, and the semi-coke is cooled, and then the preheated carbon dioxide and water vapor enter the high-temperature zone in the lower part of the carbonization chamber, and react with the semi-coke to gasify, and the generated hydrogen and carbon monoxide rise together with the carbon dioxide and water vapor and enter the dry distillation zone, preheating zone and drying zone of the carbonization chamber in turn, and finally are discharged from the carbonization chamber together with the dry distillation gas, and then enter the purification system through the gas collecting pipe for purification treatment.

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