CN211822292U - Coke oven raw gas and waste gas waste heat recycling system - Google Patents

Abstract

A coke oven raw gas and waste gas waste heat recovery and reutilization system comprises a coke oven, a high-temperature waste heat boiler, a waste gas purification device, a steam turbine, an oil-gas separator, a low-temperature waste heat boiler, a gas cooler, an oil-water separator and a low-temperature waste heat recovery device, the scheme is simultaneously provided with the high-temperature waste heat boiler, the low-temperature waste heat boiler and the low-temperature waste heat recovery device, the effective recovery and reutilization of the high-temperature sensible heat of the raw gas, the low-temperature waste heat of the heavy tar and the low-temperature waste heat of the raw gas at 60-100 ℃ are realized, the heavy tar and the light tar which are greatly existed in the raw gas can be recovered, the raw gas is created for enterprises, the economic and social benefits are good, the raw gas is conveyed into a first flue gas pipeline to exchange heat with the coke oven waste gas in a second flue gas pipeline, the partial recovery and reutilization of the high-temperature, no additional heater is needed, thereby greatly reducing the investment and treatment cost of the coke oven waste gas and being beneficial to the energy conservation and consumption reduction of coking enterprises.

Description

Coke oven raw gas and waste gas waste heat recycling system

Technical Field

The utility model relates to a coke oven waste heat recovery technical field especially relates to a coke oven raw coke oven gas and waste gas waste heat recovery system of recycling.

Background

One coke oven contains dozens of coking chambers (such as 56), the coking chambers generate a large amount of raw gas at 600-800 ℃ during the operation period and have high heat energy, the process flow commonly adopted by the coke ovens at home and abroad at present is to collect the raw gas generated in the dry distillation process of the coking chambers into the top space of the coking chambers, the raw gas enters a gas collecting pipe through an ascending pipe and a bridge pipe, the raw gas is directly sprayed and cooled to about 85 ℃ by ammonia water in the bridge pipe, the cooled raw gas contains a large amount of components such as tar and the like, the temperature is still high, and the raw gas can be converted into coke oven gas through various treatments, so that the cost of preparing natural gas (SNG, CNG and LNG) from the coke oven gas is too high, and the natural gas product lacks obvious competitiveness. The process wastes a large amount of heat energy sensible heat in the raw gas and also wastes components such as light tar, heavy tar and the like with higher economic value in the raw gas.

The coke oven generates a large amount of raw coke oven gas and a large amount of coke oven waste gas, the temperature of the waste gas is about 220-.

Disclosure of Invention

In view of the above, it is necessary to provide a system for recycling waste heat of raw gas and waste gas of a coke oven.

A coke oven crude gas and waste gas waste heat recycling system comprises a coke oven, a high-temperature waste heat boiler, a waste gas purifying device, a steam turbine, an oil-gas separator, a low-temperature waste heat boiler, a gas cooler, an oil-water separator and a low-temperature waste heat recovering device, wherein the outlet end of the coke oven crude gas is connected with a first inlet of the high-temperature waste heat boiler, the outlet end of the coke oven waste gas is connected with one end of the waste gas purifying device, the other end of the waste gas purifying device is connected with a third inlet of a refrigerant evaporator, a first outlet of the high-temperature waste heat boiler is connected with a first inlet of the oil-gas separator, one end of the steam turbine is connected with a second outlet of the high-temperature waste heat boiler, the other end of the steam turbine is connected with a second inlet of a heat exchanger, a first outlet of the oil-gas separator, the first outlet of the low-temperature waste heat boiler is connected with the second inlet of the oil-gas separator, the second outlet of the low-temperature waste heat boiler is connected with the second inlet of the high-temperature waste heat boiler, the third outlet of the low-temperature waste heat boiler is connected with the heavy tar storage tank, the first outlet of the gas cooler is connected with the first inlet of the oil-water separator, the first outlet of the oil-water separator is connected with the third inlet of the oil-gas separator, the second outlet of the oil-water separator is connected with the light tar storage tank, the second outlet of the oil-water separator is connected with the ammonia water pool, one end of the low-temperature waste heat recovery device is connected with the second outlet of the gas cooler, the other end of the low-temperature waste heat recovery device is connected with the second inlet of the low-temperature waste heat boiler, the waste gas purification device comprises a denitration tower, a desulfurization tower and a glass, one end of the desulfurization tower is connected with the other end of the denitrification tower, one end of the glass fiber bag type dust remover is connected with the other end of the desulfurization tower, the other end of the glass fiber bag type dust remover is connected with a third inlet of the refrigerant evaporator, the low-temperature waste heat recovery device comprises a refrigerant evaporator, a vapor-liquid separator, a compressor, a heat exchanger and a hot water storage device, a first inlet of the refrigerant evaporator is connected with a second outlet of the gas cooler, a first outlet of the refrigerant evaporator is connected with the coke oven gas cabinet, a third outlet of the refrigerant evaporator is connected with an external chimney, one end of the vapor-liquid separator is connected with the second outlet of the refrigerant evaporator, one end of the compressor is connected with the other end of the vapor-liquid separator, a first inlet of the heat exchanger is connected with the other end of the compressor, a first outlet of the heat exchanger is connected with the second inlet of the refrigerant evaporator, and a first outlet of the hot water storage is connected with a second inlet of the low-temperature waste heat boiler.

Preferably, a condenser is further arranged between the steam turbine and the heat exchanger.

Preferably, a deaerator is further arranged between the first outlet of the hot water storage and the second inlet of the low-temperature waste heat boiler, and the hot water storage is further provided with a second outlet.

Preferably, a first regulating valve is further arranged on a flue connecting the coke oven crude gas outlet end and the first inlet of the high-temperature waste heat boiler, and a second regulating valve is further arranged on a pipeline connecting the first inlet of the refrigerant evaporator and the second outlet of the gas cooler.

Preferably, a first temperature sensor is further arranged on a pipeline connecting the first inlet of the refrigerant evaporator and the second outlet of the gas cooler, and a second temperature sensor is further arranged on a pipeline connecting the first outlet of the refrigerant evaporator and the coke oven gas cabinet.

Preferably, a first flue gas pipeline is further arranged on a flue of the coke oven crude gas outlet end and a first inlet of the high-temperature waste heat boiler, a first gas inlet is arranged at one end of the first flue gas pipeline, a first gas outlet is arranged at the other end of the first flue gas pipeline, a second flue gas pipeline is further arranged on a flue of one end of the denitration tower connected with the coke oven waste gas outlet end, two ends of the second flue gas pipeline are sealed, the second flue gas pipeline is arranged in the first flue gas pipeline, the axis of the second flue gas pipeline is coincident with the axis of the first flue gas pipeline, a second gas inlet is arranged at one side of the end part of the second flue gas pipeline, a second gas outlet is arranged at the other side of the end part of the second flue gas pipeline, a plurality of transverse fixing plates and vertical fixing plates are arranged between the first flue gas pipeline and the second flue gas pipeline, and one, the horizontal fixing plate other end sets up on second flue gas pipeline outer wall, vertical fixing plate one end sets up on first flue gas pipeline inner wall, the vertical fixing plate other end sets up on second flue gas pipeline outer wall, horizontal fixing plate, vertical fixing plate set up along first flue gas pipeline axis direction is crisscross.

Preferably, the transverse fixing plate comprises an upper left fixing plate and a right fixing plate, and the left fixing plate and the right fixing plate are arranged in a staggered mode along the axis direction of the first flue gas pipeline; the vertical fixing plate comprises an upper fixing plate and a lower fixing plate, and the upper fixing plate and the lower fixing plate are arranged in a staggered mode along the axis direction of the first flue gas pipeline.

Preferably, the inside a plurality of heat absorption units that still are provided with of second flue gas pipeline, heat absorption unit one end sets up on second flue gas pipeline inner wall and contacts with the upper fixed plate, bottom plate, left fixed plate, right fixed plate other end, the heat absorption unit other end extends to inside the second flue gas pipeline, the heat absorption unit includes connecting plate, fin, connecting plate one end and upper fixed plate, bottom plate, left fixed plate, right fixed plate other end contact in second flue gas pipeline inner wall, be provided with a plurality of fins on connecting plate upper surface, the lower surface.

Preferably, the fin is a plate fin type fin or a tube fin type fin or a spiral type fin.

Preferably, the outer wall of the first flue gas pipeline is further provided with a heat insulation layer.

This scheme sets up high temperature exhaust-heat boiler simultaneously, low temperature exhaust-heat boiler, low temperature waste heat recovery device, the high temperature sensible heat of raw coke oven gas has been realized, the abundant recovery and the reuse of low temperature waste heat, effectively reduce raw coke oven gas heat energy wasting of resources, the superheated steam who still will retrieve simultaneously promotes the steam turbine electricity generation, effectively practice thrift the electric power cost of enterprise, further reduce coke manufacturing cost, promote coke product competitiveness, still realize the accurate control of coke oven gas temperature, help reducing the manufacturing cost of follow-up coke oven gas system natural gas by a wide margin, promote the competitiveness of natural gas product.

This scheme is through setting up low temperature exhaust-heat boiler, can also make heavy tar low temperature waste heat by the recovery after by the separation, and wherein most heavy tar is carried to heavy tar storage tank in as the by-product, through setting up oil water separator, can also make light tar and aqueous ammonia phase separation, wherein most light tar is carried to light tar storage tank in as the by-product. According to the scheme, the high-temperature sensible heat recovery, the low-temperature waste heat recovery of the heavy tar, the low-temperature waste heat recovery of the crude gas at the temperature of 60-100 ℃ and the superheated steam power generation are realized, meanwhile, the heavy tar and the light tar which are abundant in the crude gas can be recovered, and the recovered heavy tar and the recovered light tar become byproducts of coking enterprises, so that benefits are created and increased for the enterprises, and the economic benefit is good.

According to the scheme, a first flue gas pipeline is arranged on a flue of a raw coke oven gas outlet end and a first inlet of a high-temperature waste heat boiler, a second flue gas pipeline is arranged on a flue of one end of a denitration tower connected with a waste coke oven gas outlet end, the raw coke oven gas is conveyed into the first flue gas pipeline to exchange heat with the waste coke oven gas in the second flue gas pipeline, on one hand, high-temperature sensible heat of the raw coke oven gas is reduced, and on the other hand, the temperature of the waste coke oven gas in the second flue gas pipeline reaches the high-efficiency denitration requirement of the waste coke oven gas after absorbing part of the high-temperature sensible heat. The first flue gas pipeline and the second flue gas pipeline are arranged at the same time, so that the partial recovery and reutilization of high-temperature sensible heat in the raw coke oven gas are realized, a heater is not needed to be additionally arranged in the denitration process of the coke oven waste gas, the process links of treating the coke oven waste gas are reduced, the investment and treatment cost of the coke oven waste gas are greatly reduced, the energy conservation and consumption reduction of a coking enterprise are facilitated, and the operation cost of the coking enterprise is reduced.

Drawings

FIG. 1 is a schematic diagram of a system for recycling waste heat of raw gas and waste gas of a coke oven.

Fig. 2 is a longitudinal section of the first flue gas duct and the second flue gas duct.

Fig. 3 is a transverse cross-sectional view of the first flue gas duct and the second flue gas duct.

In the figure: the system comprises a coke oven 10, a first regulating valve 11, a first flue gas pipeline 12, a first gas inlet 121, a first gas outlet 122, a transverse fixing plate 123, a left fixing plate 1231, a right fixing plate 1232, a vertical fixing plate 124, an upper fixing plate 1241, a lower fixing plate 1242, a heat insulation layer 125, a second flue gas pipeline 13, a second gas inlet 131, a second gas outlet 132, a heat absorption unit 133, a connecting plate 1331, a fin 1332, a high-temperature waste heat boiler 20, a steam turbine 30, a condenser 31, an oil-gas separator 40, a low-temperature waste heat boiler 50, a gas cooler 60, a second regulating valve 61, a first temperature sensor 62, an oil-water separator 70, a refrigerant evaporator 81, a second temperature sensor 811, a gas-liquid separator 82, a compressor 83, a heat exchanger 84, a hot water storage 85, a deaerator 851, a denitration tower 91, a desulfurization tower 92 and a.

Detailed Description

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

Referring to fig. 1 to 3, the utility model provides a coke oven crude gas and waste gas waste heat recovery system, including coke oven 10, high temperature exhaust-heat boiler 20, steam turbine 30, oil and gas separator 40, low temperature exhaust-heat boiler 50, gas cooler 60, oil-water separator 70, low temperature waste heat recovery device, coke oven 10 crude gas outlet end is connected with the first entry of high temperature exhaust-heat boiler 20 to carry a large amount of crude gas of 600 ~ 800 ℃ in coke oven 10 to high temperature exhaust-heat boiler 20, so that the water in high temperature exhaust-heat boiler 20 is heated and vaporized to produce superheated steam of 4 ~ 25MPa, and drop the temperature of crude gas to 300 ~ 450 ℃, coke oven 10 waste gas outlet end is connected with one end of waste gas purification device, the other end of waste gas purification device is connected with the third entry of refrigerant evaporator 81, the first exit of high temperature exhaust-heat boiler 20 is connected with the first entry of oil and gas separator 40, conveying raw gas at 300-450 ℃ into an oil-gas separator 40, wherein one end of a steam turbine 30 is connected with a second outlet of a high-temperature waste heat boiler 20 to convey superheated steam into the steam turbine 30, the superheated steam pushes the steam turbine 30 to generate electricity, the process steam is changed into exhaust steam at 30-70 ℃ after the electricity is generated by the steam turbine 30, the other end of the steam turbine 30 is connected with a second inlet of a heat exchanger 84 to convey the exhaust steam into the heat exchanger 84 to exchange heat between the exhaust steam and a high-temperature high-pressure gaseous refrigerant medium conveyed by a compressor 83, tar is sprayed into the oil-gas separator 40 to separate heavy tar from the raw gas, the temperature of the heavy tar is 130-240 ℃, the heavy tar still has high heat energy, the temperature of the raw gas is reduced from 300-450 ℃ to 180-260 ℃, a first outlet of the oil-gas separator 40 is connected with a first inlet of a gas cooler 60 to convey the raw gas from which the heavy tar is removed into a gas cooler 60, the second inlet and outlet of the oil-gas separator 40 is connected with the first inlet of the low-temperature waste heat boiler 50 so as to convey heavy tar into the low-temperature waste heat boiler 50, the heavy tar is separated after the low-temperature waste heat boiler 50 exchanges heat with water, the water in the low-temperature waste heat boiler 50 is heated and vaporized to generate superheated steam of 0.1-3 MPa, the first outlet of the low-temperature waste heat boiler 50 is connected with the second inlet of the oil-gas separator 40 so as to convey a small part of the heavy tar into the oil-gas separator 40 for spraying crude gas, the second outlet of the low-temperature waste heat boiler 50 is connected with the second inlet of the high-temperature waste heat boiler 20 so as to convey the superheated steam of 0.1-3 MPa into the high-temperature waste heat boiler 20, the third outlet of the low-temperature waste heat boiler 50 is connected with a heavy tar storage tank so as to convey most of heavy tar byproducts into the heavy tar storage tank, and, reducing the temperature of the raw coke oven gas from 180-260 ℃ to 60-100 ℃ to separate light tar from the raw coke oven gas, wherein a first outlet of the gas cooler 60 is connected with a first inlet of an oil-water separator 70 to convey a light tar and ammonia water mixture into the oil-water separator 70, the oil-water separator 70 separates the light tar and ammonia water mixture, a first outlet of the oil-water separator 70 is connected with a third inlet of the oil-water separator 40 to convey a small part of light tar into the oil-gas separator 40 for spraying the raw coke oven gas, a second outlet of the first outlet of the oil-water separator 70 is connected with a light tar storage tank to convey a large part of light tar byproducts into the light tar storage tank, a second outlet of the oil-water separator 70 is connected with an ammonia water tank to convey the separated ammonia water into the ammonia water tank for recycling use by the gas cooler 60, the ammonia water use cost is reduced, one end of the low-temperature waste heat recovery device is connected with a second outlet of the gas cooler 60, the other end of the low-temperature waste heat recovery device is connected with a second inlet of the low-temperature waste heat boiler 50, the waste gas purification device comprises a denitration tower 91, a desulfurization tower 92 and a glass fiber bag type dust remover 93, one end of the denitration tower 91 is connected with a waste gas outlet end of the coke oven 10, NOx in the coke oven waste gas is removed by the denitration tower 91, one end of the desulfurization tower 92 is connected with the other end of the denitration tower 91, SOx in the coke oven waste gas is removed by the desulfurization tower 92, one end of the glass fiber bag type dust remover 93 is connected with the other end of the desulfurization tower 92, the glass fiber bag type dust remover 93 is used for removing dust particles in the coke oven waste gas, at the time, the temperature of the coke oven waste gas is at 200 ℃, the low-, the coke oven waste gas with low-temperature waste heat is conveyed into a refrigerant evaporator 81, a refrigerant medium in the refrigerant evaporator 81 exchanges heat with the coke oven waste gas to reduce the temperature of the coke oven waste gas from 100-200 ℃ to 20-60 ℃ to form the waste gas, the low-temperature waste heat recovery device comprises a refrigerant evaporator 81, a vapor-liquid separator 82, a compressor 83, a heat exchanger 84 and a hot water storage 85, a first inlet of the refrigerant evaporator 81 is connected with a second outlet of a gas cooler 60 to convey the raw coke gas at 60-100 ℃ into the refrigerant evaporator 81, the refrigerant medium in the refrigerant evaporator 81 exchanges heat with the raw coke gas to reduce the temperature of the raw coke oven gas from 60-100 ℃ to 20-40 ℃ to form the coke oven gas, a first outlet of the refrigerant evaporator 81 is connected with a coke oven gas cabinet to convey the coke oven gas into the gas cabinet, the third outlet of the refrigerant evaporator 81 is connected with an external chimney to convey the waste gas to the external chimney to achieve the standard discharge of the coke oven waste gas, one end of the vapor-liquid separator 82 is connected with the second outlet of the refrigerant evaporator 81 to separate vapor from liquid of the vaporized refrigerant, one end of the compressor 83 is connected with the other end of the vapor-liquid separator 82 to convey the gaseous refrigerant to the compressor 83, the compressor 83 compresses the gaseous refrigerant into the high-temperature high-pressure gaseous refrigerant, the first inlet of the heat exchanger 84 is connected with the other end of the compressor 83 to exchange heat between the high-temperature high-pressure gaseous refrigerant and the exhaust steam in the heat exchanger 84, the exhaust steam absorbs heat to form hot water at 80-100 ℃, the first outlet of the heat exchanger 84 is connected with the second inlet of the refrigerant evaporator 81 to convey the refrigerant with reduced temperature after heat exchange to the evaporator 81, for recycling, the first inlet of the hot water storage 85 is connected with the second outlet of the heat exchanger 84 to deliver the hot water into the hot water storage 85, and the first outlet of the hot water storage 85 is connected with the second inlet of the low temperature waste heat boiler 50 to deliver the hot water into the low temperature waste heat boiler 50.

The scheme is provided with a high-temperature waste heat boiler 20, a low-temperature waste heat boiler 50 and a low-temperature waste heat recovery device, wherein the high-temperature waste heat boiler 20 fully recovers high-temperature sensible heat in raw gas at 600-800 ℃, so that water in the high-temperature waste heat boiler 20 is heated and vaporized to generate superheated steam at 4-25 MPa, the superheated steam is conveyed to a steam turbine 30 to generate electricity, the temperature of the raw gas is reduced to 300-450 ℃, the low-temperature waste heat boiler 50 fully recovers oil-gas separator 40 to separate low-temperature waste heat of heavy tar at 130-240 ℃, the heavy tar is separated from the water after heat exchange in the low-temperature waste heat boiler 50, the water in the low-temperature waste heat boiler 50 is heated and vaporized to generate superheated steam at 0.1-3 MPa, the low-temperature waste heat recovery device fully recovers low-temperature waste heat of the raw gas at 60-100 ℃, the raw gas is converted into coke oven gas at 20-40 ℃, and simultaneously the waste steam/cooling water exchanges heat with high-, the waste steam/cooling water can be changed into hot water at 80-100 ℃ after absorbing heat. Through setting up high temperature exhaust-heat boiler 20, low temperature exhaust-heat boiler 50, low temperature exhaust-heat recovery device simultaneously, realized the abundant recovery and the reuse of raw coke oven gas high temperature sensible heat, low temperature waste heat, effectively reduced raw coke oven gas heat energy wasting of resources, still promote the electricity generation of steam turbine 30 with the superheated steam who retrieves simultaneously, effectively practice thrift the electric power cost of enterprise.

In the scheme, water used in the heat exchanger 84, the hot water storage 85, the low-temperature waste heat boiler 50, the high-temperature waste heat boiler 20 and the steam turbine 30 is arranged in a circulating mode, the high-temperature waste heat boiler 20 generates superheated steam, the superheated steam pushes the steam turbine 30 to generate electricity and then becomes exhaust steam/cooling water, the exhaust steam/cooling water is conveyed into the heat exchanger 84 to exchange heat with high-temperature high-pressure gaseous cold medium to form hot water, the hot water is conveyed into the low-temperature waste heat boiler 50 to generate superheated steam of 0.1-3 MPa, then the superheated steam is conveyed into the high-temperature waste heat boiler 20 to generate superheated steam of 4-25 MPa, in the process of waterway circulation use, water resources are fully used, the water cost is effectively reduced, meanwhile, the hot water in the hot water storage 85 is conveyed into the low-temperature waste heat boiler 50 firstly, the low-temperature waste heat boiler 50 heats the hot water to, the low-temperature waste heat boiler 50 has a higher utilization rate of the heavy tar waste heat, the generated superheated steam pressure is higher, then the superheated steam with 0.1-3 MPa is conveyed to the high-temperature waste heat boiler 20 to exchange heat with the raw gas with the temperature of 600 plus 800 ℃, the superheated steam with higher pressure can be generated, the superheated steam with 4-25 MPa can be generated by the high-temperature waste heat boiler 20 under the condition of lower working load, and the utilization rate of the high-temperature waste heat boiler 20 to the high-temperature sensible heat of the raw gas with the temperature of 600 plus 800 ℃ is greatly improved.

According to the scheme, the low-temperature waste heat boiler 50 is arranged, so that the low-temperature waste heat of the heavy tar is recovered and then separated, a small part of the heavy tar is conveyed to the oil-gas separator 40 and is used for spraying the raw gas, a large part of the heavy tar is conveyed to the heavy tar storage tank as a byproduct, the oil-water separator 70 is arranged so that the light tar is separated from the ammonia water, a small part of the light tar is conveyed to the oil-gas separator 40 and is used for spraying the raw gas, and a large part of the light tar is conveyed to the light tar storage tank as a byproduct. According to the scheme, the high-temperature sensible heat recovery, the low-temperature waste heat recovery of heavy tar, the low-temperature waste heat recovery of the crude gas at the temperature of 60-100 ℃ and the superheated steam power generation of the crude gas are realized, meanwhile, a large amount of heavy tar and light tar existing in the crude gas can be recovered, the recovered heavy tar and light tar become byproducts of a coking enterprise, benefits can be created and increased for the enterprise, good economic benefits are achieved, the workload of treating the heavy tar and the light tar in a subsequent natural gas purification section for producing coke oven gas can be greatly reduced, and the treatment cost of a subsequent section is effectively reduced.

In the scheme, a first flue gas pipeline 12 is arranged on a flue of a raw gas outlet end of a coke oven 10 and a first inlet of a high-temperature waste heat boiler 20, a second flue gas pipeline 13 is arranged on a flue connected with a waste gas outlet end of the coke oven at one end of a denitration tower 91, the second flue gas pipeline 13 is arranged in the first flue gas pipeline 12, the raw gas in the first flue gas pipeline 12 has a large amount and high-temperature sensible heat, the coke oven waste gas in the second flue gas pipeline 13 has a large amount and low waste heat, the raw gas is conveyed into the first flue gas pipeline 12 to exchange heat with the coke oven waste gas in the second flue gas pipeline 13, on one hand, the high-temperature sensible heat of the raw gas is reduced, for example, the temperature of the raw gas is reduced by about 100 ℃ so as to reduce the maintenance cost of the high-temperature resistant flue gas pipeline of the raw gas, on the other hand, the coke oven waste gas in the second flue gas pipeline 13 absorbs part of the high-, further leading the coke oven waste gas to reach the high-efficiency denitration requirement. The first flue gas pipeline 12 and the second flue gas pipeline 13 are arranged at the same time, so that part of high-temperature sensible heat in the raw coke oven gas is recovered, the recovered heat is transferred to the coke oven waste gas in the second flue gas pipeline 13, the temperature of the coke oven waste gas is increased to 300-400 ℃, the recovery and the reutilization of the heat of the raw coke oven gas are realized, a heater is not needed to be additionally arranged in the denitration process of the coke oven waste gas, the subsequent treatment process links of the coke oven waste gas are reduced, the investment and the treatment cost of the coke oven waste gas are greatly reduced, the energy conservation and the consumption reduction of a coking enterprise are facilitated, and the operation cost of the.

Specifically, a first inlet of the refrigerant evaporator 81 is connected with a second outlet of the gas cooler 60 to convey raw gas at 60-100 ℃ into the refrigerant evaporator 81, a third inlet of the refrigerant evaporator 81 is connected with the other end of the glass fiber bag type dust collector 93 to convey coke oven waste gas at 100-200 ℃ into the refrigerant evaporator 81, two independent gas conveying chambers are respectively arranged in the refrigerant evaporator 81, two sides of a refrigerant evaporation pipe are respectively arranged in the two independent gas conveying chambers to enable the raw gas and the coke oven waste gas to independently exchange heat with a cooling medium in the refrigerant evaporator 81, the refrigerant evaporator 81 can simultaneously absorb low-temperature waste heat of the raw gas and the coke oven waste gas, the recovered low-temperature waste heat is converted into hot water through a subsequent heat exchanger 84, and the hot water is conveyed to a production line for recycling use, the method can effectively avoid a large amount of low-temperature waste heat in the raw gas and the coke oven waste gas from escaping into the atmosphere, recover and recycle the large amount of low-temperature waste heat in the raw gas and the coke oven waste gas, greatly increase the heat utilization rate of the raw gas and the coke oven waste gas, convert the raw gas and the coke oven waste gas into hot water for the subsequent working section to be recycled, and has good economic benefit.

Further, a condenser 31 is arranged between the steam turbine 30 and the heat exchanger 84 to reduce the temperature of the exhaust steam and condense the exhaust steam into cooling water at 15-30 ℃.

Specifically, the temperature of the cooling water is lower than that of the exhaust steam, and when the cooling water exchanges heat with the high-temperature high-pressure gaseous refrigerant medium in the heat exchanger 84, more heat in the high-temperature high-pressure gaseous refrigerant medium can be absorbed under the same condition, so that the temperature of the refrigerant medium returned to the refrigerant evaporator 81 for recycling is lower, the heat absorption capacity of the refrigerant medium on the raw coke oven gas can be further increased, and further the temperature of the raw coke oven gas is obviously reduced after the raw coke oven gas passes through the refrigerant evaporator 81, namely the temperature of the coke oven gas is controlled to be 20-40 ℃.

The coke oven gas is used as a raw material gas for preparing natural gas, and is processed by various processes subsequently, but the temperature of the coke oven gas at an inlet is required to be lower, but in the actual production process, conventional processes such as water spraying and the like are mostly adopted, so that the temperature of the coke oven gas at the inlet is always higher than 50 ℃, the production cost of the subsequent process is increased, and the production requirement is difficult to meet.

According to the scheme, the condenser 31 is arranged to convert exhaust steam into cooling water, then the cooling water is conveyed to the heat exchanger 84 to exchange heat with the high-temperature high-pressure gaseous cooling medium, so that the temperature of the coke oven gas is kept at 20-40 ℃, the working load of the refrigerant evaporator 81 can be greatly reduced, the operation cost of the low-temperature waste heat recovery device is effectively reduced, meanwhile, the temperature of the cooling water can be reduced to be lower, such as 5-10 ℃, by improving the working load of the condenser 31, then the cooling water with the temperature is conveyed to the heat exchanger 84 to exchange heat with the high-temperature high-pressure gaseous cooling medium, the temperature of the coke oven gas can be further reduced, such as 10-20 ℃, the application range of the temperature at the coke oven gas inlet can be favorably improved, and the subsequent treatment cost of preparing natural gas from.

Further, a deaerator 851 is further arranged between the first outlet of the hot water storage 85 and the second inlet of the low-temperature waste heat boiler 50 to remove free oxygen in hot water, so that the free oxygen entering the circulating water path of the steam turbine 30 is not overproof, the hot water storage 85 is further provided with a second outlet to convey hot water to other hot water use places of a plant area, such as a methanation section, a heating pipeline and the like, and the cost of the other hot water use places of the plant area is reduced.

Further, a first regulating valve 11 is further arranged on a flue connecting the raw gas outlet end of the coke oven 10 and the first inlet of the high-temperature waste heat boiler 20, and a second regulating valve 61 is further arranged on a pipeline connecting the first inlet of the refrigerant evaporator 81 and the second outlet of the gas cooler 60.

Specifically, the first temperature sensor 62 monitors the temperature of the raw coke oven gas at the first inlet of the refrigerant evaporator 81, and compares the temperature of the raw coke oven gas with a preset temperature: when the temperature of the raw gas is not less than the preset temperature, the first regulating valve 11 is not regulated; when the temperature of the raw gas is lower than the preset temperature, it is indicated that the flow rate of the raw gas output from the raw gas outlet end of the coke oven 10 is too low, or the work load of the high-temperature waste heat boiler 20 is too high, the flow rate of the raw gas output from the coke oven 10 is increased by adjusting the first adjusting valve 11, so that the total inflow amount of the raw gas conveyed to the high-temperature waste heat boiler 20 is increased, more raw gas is conveyed to the high-temperature waste heat boiler 20 to release heat under the condition that the work loads of the high-temperature waste heat boiler 20, the oil-gas separator 40 and the gas cooler 60 are not adjusted, and the temperature of the raw gas at the first inlet of the refrigerant evaporator 81 is increased to the preset temperature; or the working load of the high-temperature waste heat boiler 20 is reduced, the heat exchange degree of the high-temperature waste heat boiler 20 to the raw coke oven gas is reduced, and the temperature of the raw coke oven gas at the first inlet of the refrigerant evaporator 81 is increased to the preset temperature under the condition that the flow speed of the raw coke oven gas output by the coke oven 10 is not adjusted.

Specifically, the second temperature sensor 811 monitors the temperature of the coke oven gas, and compares the temperature of the coke oven gas with a preset temperature: when the temperature of the coke oven gas is lower than the preset temperature, the second regulating valve 61 is not regulated; when the temperature of the coke oven gas is not less than the preset temperature, it is indicated that the flow rate of the crude gas in the refrigerant evaporator 81 is too high, or the working load of the refrigerant evaporator 81 is too low, the flow rate of the crude gas conveyed into the refrigerant evaporator 81 is reduced by adjusting the second adjusting valve 61, the total inflow amount of the crude gas conveyed into the refrigerant evaporator 81 is reduced, and under the condition that the working load of the refrigerant evaporator 81 is not adjusted, the refrigerant medium in the refrigerant evaporator 81 and the limited crude gas exchange heat sufficiently to enable the temperature of the coke oven gas to be reduced to the preset temperature; or the working load of the refrigerant evaporator 81 is increased, the heat exchange degree of the refrigerant evaporator 81 to the raw coke oven gas is increased, and the temperature of the coke oven gas is reduced to the preset temperature under the condition that the flow rate of the raw coke oven gas is not adjusted.

The temperature of the raw coke oven gas at the first inlet of the refrigerant evaporator 81 is accurately controlled by arranging the first regulating valve 11 and the first temperature sensor 62; the second regulating valve 61 and the second temperature sensor 811 are arranged, so that the temperature of the coke oven gas is accurately controlled; the method can control the temperature of the coke oven gas within a proper range while ensuring that the waste heat of the raw coke oven gas is fully recycled, is favorable for greatly reducing the production cost of preparing the natural gas from the subsequent coke oven gas, and improves the competitiveness of natural gas products.

Further, a first temperature sensor 62 is further disposed on a pipeline connecting a first inlet of the refrigerant evaporator 81 and a second outlet of the gas cooler 60 to detect a temperature of the raw coke oven gas at the first inlet of the refrigerant evaporator 81, and a second temperature sensor 811 is further disposed on a pipeline connecting the first outlet of the refrigerant evaporator 81 and the coke oven gas cabinet to detect a temperature of the coke oven gas.

Further, a first flue gas pipeline 12 is further arranged on a flue of the raw gas outlet end of the coke oven 10 and the first inlet of the high-temperature waste heat boiler 20, the first flue gas pipeline 12 is a rigid corrosion-resistant hollow cylinder, one end of the first flue gas pipeline 12 is provided with a first gas inlet 121 to be connected with a flue gas pipeline on the upper half section between the raw gas outlet end of the coke oven 10 and the first inlet of the high-temperature waste heat boiler 20, the other end of the first flue gas pipeline 12 is provided with a first gas outlet 122 to be connected with a flue gas pipeline on the lower half section between the raw gas outlet end of the coke oven 10 and the first inlet of the high-temperature waste heat boiler 20, a second flue gas pipeline 13 is further arranged on a flue of one end of the denitration tower 91 connected with the waste gas outlet end of the coke oven, the second flue gas pipeline 13 is a rigid corrosion-resistant heat-conducting hollow cylinder, two ends of which are sealed, the axis of the second flue gas pipeline 13 coincides with the axis of the first flue gas pipeline 12, one side of the end of the second flue gas pipeline 13 is provided with a second gas inlet 131 for conveying coke oven waste gas in the waste gas outlet end of the coke oven 10 to the second flue gas pipeline 13, the other side of the end of the second flue gas pipeline 13 is provided with a second gas outlet 132 for conveying the heated coke oven waste gas in the second flue gas pipeline 13 to the denitration tower 91, a plurality of transverse fixing plates 123 and vertical fixing plates 124 are arranged between the first flue gas pipeline 12 and the second flue gas pipeline 13, one end of each transverse fixing plate 123 is arranged on the inner wall of the first flue gas pipeline 12, the other end of each transverse fixing plate 123 is arranged on the outer wall of the second flue gas pipeline 13, one end of each vertical fixing plate 124 is arranged on the inner wall of the first flue gas pipeline 12, and the other end of each vertical fixing plate, the horizontal fixing plates 123 and the vertical fixing plates 124 are staggered along the axial direction of the first flue gas duct 12.

Further, the transverse fixing plate 123 includes a left fixing plate 1231 and a right fixing plate 1232, and the left fixing plate 1231 and the right fixing plate 1232 are staggered along the axial direction of the first flue gas duct 12; the vertical fixing plate 124 includes an upper fixing plate 1241 and a lower fixing plate 1242, and the upper fixing plate 1241 and the lower fixing plate 1242 are staggered along the axial direction of the first flue gas duct 12.

Specifically, the upper fixing plate 1241, the lower fixing plate 1242, the left fixing plate 1231 and the right fixing plate 1232 have the same structure and are staggered along the axial direction of the first flue gas duct 12, and the arrangement direction of the upper fixing plate 1241, the lower fixing plate 1242, the left fixing plate 1231 and the right fixing plate 1232 is perpendicular to the conveying direction of the raw coke oven gas, so that the flow velocity of the raw coke oven gas in the first flue gas duct 12 is slowed down, a local turbulent flow is formed, the flowing distance of the raw coke oven gas in the first flue gas duct 12 is prolonged, the contact time of the raw coke oven gas and the second flue gas duct 13 is further prolonged, the heat exchange between the raw coke oven gas in the first flue gas duct 12 and the coke oven exhaust gas in the second; meanwhile, the contact time of the raw coke oven gas with the transverse fixing plate 123 and the vertical fixing plate 124 can be increased, so that the transverse fixing plate 123 and the vertical fixing plate 124 absorb more heat in the raw coke oven gas, and more heat is transferred to the connecting plate 1331 inside the second flue gas pipeline 13.

Preferably, the upper fixing plate 1241 is a copper plate, has excellent thermal conductivity, and can effectively absorb high-temperature sensible heat in the raw coke oven gas in the first flue gas duct 12, so as to transfer more heat to the coke oven exhaust gas in the second flue gas duct 13, improve the thermal conductivity of the raw coke oven gas in the first flue gas duct 12 and the coke oven exhaust gas in the second flue gas duct 13, and effectively improve the temperature of the coke oven exhaust gas.

Further, a plurality of heat absorbing units 133 are further disposed inside the second flue gas duct 13, one end of each heat absorbing unit 133 is disposed on the inner wall of the second flue gas duct 13 and is in contact with the other ends of the upper fixing plate 1241, the lower fixing plate 1242, the left fixing plate 1231, and the right fixing plate 1232, the other end of each heat absorbing unit 133 extends into the second flue gas duct 13, each heat absorbing unit 133 includes a connecting plate 1331 and a fin 1332, the shape of the connecting plate 1331 is matched with the shape and the size of the upper fixing plate 1241, the shape of the lower fixing plate 1242, the shape of the left fixing plate 1231, and the size of the right fixing plate 1232 are preferably the same, the connecting plate 1331 is a copper plate, one end of the connecting plate 1331 is in contact with and fixed to the inner wall of the second flue gas duct 13, so as to directly transfer the heat absorbed by the upper fixing plate 1241, the lower fixing plate 1242, the left fixing plate 1231, and the right fixing plate 123, so that the coke oven exhaust gas in the second flue gas duct 13 can fully exchange heat with the upper fixing plate 1241, the lower fixing plate 1242, the left fixing plate 1231 and the right fixing plate 1232, and the upper surface and the lower surface of the connecting plate 1331 are uniformly provided with a plurality of fins 1332, so as to improve the heat exchange efficiency of the coke oven exhaust gas.

Specifically, when the raw coke oven gas in the first flue gas duct 12 exchanges heat with the coke oven exhaust gas in the second flue gas duct 13, the raw coke oven gas is influenced by the material and mechanics of the second flue gas duct 13, the heat conductivity is limited, the temperature of the coke oven exhaust gas can be increased, but the temperature rise efficiency is limited, and the temperature of the coke oven exhaust gas after heat exchange is difficult to reach the requirement of 300-, effectively raising the temperature of the coke oven exhaust gas in the second flue gas duct 13.

Further, the fin 1332 is a plate fin type fin or a tube fin or a spiral fin to improve the heat absorption capacity and the heat exchange efficiency of the connection plate 1331.

Further, an insulating layer 125 is further disposed on the outer wall of the first flue gas pipeline 12 to prevent the high-temperature heat in the first flue gas pipeline 12 from escaping to the external environment, and improve the utilization rate of the high-temperature sensible heat of the raw coke oven gas.

The embodiment of the utility model provides a module or unit in the device can merge, divide and delete according to actual need.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

Claims (10)

1. The utility model provides a coke oven raw coke oven gas and waste gas waste heat recovery system of recycling which characterized in that: the system comprises a coke oven, a high-temperature waste heat boiler, a waste gas purification device, a steam turbine, an oil-gas separator, a low-temperature waste heat boiler, a gas cooler, an oil-water separator and a low-temperature waste heat recovery device, wherein a raw coke oven gas outlet end of the coke oven is connected with a first inlet of the high-temperature waste heat boiler, a waste gas outlet end of the coke oven is connected with one end of the waste gas purification device, the other end of the waste gas purification device is connected with a third inlet of a refrigerant evaporator, a first outlet of the high-temperature waste heat boiler is connected with a first inlet of the oil-gas separator, one end of the steam turbine is connected with a second outlet of the high-temperature waste heat boiler, the other end of the steam turbine is connected with a second inlet of a heat exchanger, the first outlet of the oil-gas separator is connected with the first inlet of the gas, the second outlet of the low-temperature waste heat boiler is connected with the second inlet of the high-temperature waste heat boiler, the third outlet of the low-temperature waste heat boiler is connected with a heavy tar storage tank, the first outlet of the gas cooler is connected with the first inlet of the oil-water separator, the first outlet of the oil-water separator is connected with the third inlet of the oil-gas separator, the second outlet of the oil-water separator is connected with a light tar storage tank, the second outlet of the oil-water separator is connected with an ammonia water pool, one end of the low-temperature waste heat recovery device is connected with the second outlet of the gas cooler, the other end of the low-temperature waste heat recovery device is connected with the second inlet of the low-temperature waste heat boiler, the waste gas purification device comprises a denitration tower, a desulfurization tower and a glass fiber bag type dust collector, one end of the denitration tower is connected with the waste gas outlet end of the coke oven, one end of the desulfurization tower is, the other end of the glass fiber bag type dust collector is connected with a third inlet of the refrigerant evaporator, the low-temperature waste heat recovery device comprises a refrigerant evaporator, a vapor-liquid separator, a compressor, a heat exchanger and a hot water storage device, the first inlet of the refrigerant evaporator is connected with the second outlet of the gas cooler, the first outlet of the refrigerant evaporator is connected with the coke oven gas cabinet, a third outlet of the refrigerant evaporator is connected with an external chimney, one end of the vapor-liquid separator is connected with a second outlet of the refrigerant evaporator, one end of the compressor is connected with the other end of the gas-liquid separator, the first inlet of the heat exchanger is connected with the other end of the compressor, the first outlet of the heat exchanger is connected with the second inlet of the refrigerant evaporator, the first inlet of the hot water storage is connected with the second outlet of the heat exchanger, and the first outlet of the hot water storage is connected with the second inlet of the low-temperature waste heat boiler.

2. The coke oven crude gas and waste gas waste heat recovery and reuse system of claim 1, characterized in that: and a condenser is also arranged between the steam turbine and the heat exchanger.

3. The coke oven crude gas and waste gas waste heat recovery and reuse system of claim 1, characterized in that: still be provided with the oxygen-eliminating device between hot-water storage ware first export and the low temperature exhaust-heat boiler second entry, hot-water storage ware still is provided with the second export.

4. The coke oven crude gas and waste gas waste heat recovery and reuse system of claim 1, characterized in that: a first adjusting valve is further arranged on a flue connecting the coke oven crude gas outlet end with the first inlet of the high-temperature waste heat boiler, and a second adjusting valve is further arranged on a pipeline connecting the first inlet of the refrigerant evaporator with the second outlet of the gas cooler.

5. The coke oven crude gas and waste gas waste heat recovery and reuse system of claim 1, characterized in that: and a first temperature sensor is also arranged on a pipeline connecting the first inlet of the refrigerant evaporator and the second outlet of the gas cooler, and a second temperature sensor is also arranged on a pipeline connecting the first outlet of the refrigerant evaporator and the coke oven gas cabinet.

6. The coke oven crude gas and waste gas waste heat recovery and reuse system of claim 1, characterized in that: a first flue gas pipeline is further arranged on a flue of the coke oven crude gas outlet end and a first inlet of the high-temperature waste heat boiler, a first gas inlet is arranged at one end of the first flue gas pipeline, a first gas outlet is arranged at the other end of the first flue gas pipeline, a second flue gas pipeline is further arranged on a flue of one end of the denitration tower connected with the coke oven waste gas outlet end, two ends of the second flue gas pipeline are sealed, the second flue gas pipeline is arranged in the first flue gas pipeline, the axis of the second flue gas pipeline is coincident with the axis of the first flue gas pipeline, a second gas inlet is arranged at one side of the end part of the second flue gas pipeline, a second gas outlet is arranged at the other side of the end part of the second flue gas pipeline, a plurality of transverse fixing plates and vertical fixing plates are arranged between the first flue gas pipeline and the second flue gas pipeline, one, the horizontal fixing plate other end sets up on second flue gas pipeline outer wall, vertical fixing plate one end sets up on first flue gas pipeline inner wall, the vertical fixing plate other end sets up on second flue gas pipeline outer wall, horizontal fixing plate, vertical fixing plate set up along first flue gas pipeline axis direction is crisscross.

7. The coke oven crude gas and waste gas waste heat recycling system of claim 6, wherein: the transverse fixing plate comprises an upper left fixing plate and a right fixing plate, and the left fixing plate and the right fixing plate are arranged in a staggered mode along the axis direction of the first flue gas pipeline; the vertical fixing plate comprises an upper fixing plate and a lower fixing plate, and the upper fixing plate and the lower fixing plate are arranged in a staggered mode along the axis direction of the first flue gas pipeline.

8. The coke oven crude gas and waste gas waste heat recycling system of claim 6, wherein: the inside a plurality of heat absorption units that still are provided with of second flue gas pipeline, heat absorption unit one end sets up on second flue gas pipeline inner wall and contacts with upper fixed plate, bottom plate, left fixed plate, the right fixed plate other end, the heat absorption unit other end extends to inside the second flue gas pipeline, the heat absorption unit includes connecting plate, fin, connecting plate one end and upper fixed plate, bottom plate, left fixed plate, the right fixed plate other end contact in second flue gas pipeline inner wall, be provided with a plurality of fins on connecting plate upper surface, the lower surface.

9. The coke oven crude gas and waste gas waste heat recovery and reuse system of claim 8, characterized in that: the fin is a plate fin type fin or a tube fin type fin or a spiral fin.

10. The coke oven crude gas and waste gas waste heat recycling system of claim 6, wherein: and the outer wall of the first flue gas pipeline is also provided with a heat insulation layer.

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