Dry quenching boiler secondary steam waste heat recycling device

Abstract

The embodiment of the invention provides a dry quenching boiler secondary steam waste heat recycling device. The dry quenching boiler secondary steam waste heat recycling device comprises a generator, a condenser, an evaporator, an absorber, a lithium bromide solution circulating pipeline and a continuous blowdown expander. Secondary steam low-grade waste heat discharged by a continuous blowdown expander of a dry quenching boiler is recycled, the recycled waste heat is converted into cold energy, and the cold energy is provided for process rooms needing cold supply, such as a boiler instrument room and a comprehensive electrical room for cooling; in winter, industrial water flowing through an absorber and a condenser is used for heating a coke dry quenching boiler and other station buildings while cooling is carried out on process rooms needing to be cooled, such as a boiler instrument room and a comprehensive electrical room, so that annual efficient energy allocation is realized. According to the embodiment of the scheme, the energy comprehensive utilization efficiency of the whole dry quenching production process is remarkably improved, the operation cost is reduced, considerable economic benefits are created, and the method has important popularization value and application prospects.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of dry quenching, in particular to a dry quenching boiler secondary steam waste heat recovery and utilization device. BACKGROUND

[0002] With the improvement of the national control requirements for flue gas emission, dry quenching (Coke Dry Quenching, CDQ, for short) has replaced wet quenching of coke (Wet quenching of coke) and become the mainstream quenching technology in the present coking market, and the dry quenching boiler waste heat utilization system matched with the dry quenching has become the focus of attention.

[0003] In the dry quenching system, the circulating gas treated by the primary dust collector enters the body through the boiler inlet, and flows through the secondary superheater, the primary superheater, the light tube evaporator, the finned tube evaporator and the economizer in turn, and exchanges heat with the boiler water vapor system, so as to realize the production of steam by using the waste heat of the circulating gas. The steam drum receives the boiler feed water from the economizer, and collects the steam-water mixture from the evaporator, the superheater and the water-cooled wall; after separation by the steam-water separation device, saturated steam is transported to the primary superheater. A continuous blowdown pipeline is arranged at the neutral plane of the steam drum and is connected with the continuous blowdown expander. The continuous blowdown expander collects the continuous blowdown water of the boiler and temporarily stores it, and discharges it into the periodic blowdown expander through the drain valve.

[0004] Among them, the secondary steam generated in the continuous blowdown expander has high quality of 0.6 MPa and 160℃, and direct discharge will cause energy waste, therefore, how to reasonably utilize this part of steam energy has become a key problem to be solved at present. SUMMARY

[0005] The purpose of the embodiment of the present application is to provide a dry quenching boiler secondary steam waste heat recovery and utilization device to improve the energy comprehensive utilization efficiency of the dry quenching process. The specific technical scheme is as follows:

[0006] A dry quenching boiler secondary steam waste heat recovery and utilization device, comprising:

[0007] A generator comprising first and second generator heat exchange pipelines that exchange heat with each other;

[0008] A condenser comprising first and second condenser heat exchange pipelines that exchange heat with each other;

[0009] An evaporator comprising first and second evaporator heat exchange pipelines that exchange heat with each other;

[0010] An absorber comprising first and second absorber heat exchange pipelines that exchange heat with each other;

[0011] The first generating heat exchange pipeline, the first absorbing heat exchange pipeline are connected in series in the lithium bromide solution circulation pipeline, wherein the first generating heat exchange pipeline has a steam outlet for discharging water vapor, and the first absorbing heat exchange pipeline has a liquid return port;

[0012] The continuous blowdown expander is connected with the inlet of the second generating heat exchange pipeline through a secondary steam outlet, so that the lithium bromide solution in the first generating heat exchange pipeline exchanges heat with the second generating heat exchange pipeline to generate water vapor;

[0013] The steam outlet of the first generating heat exchange pipeline and the steam inlet of the first condensing heat exchange pipeline are connected through a first water vapor pipeline; the inlet of the second condensing heat exchange pipeline is connected with a first industrial water pipeline, so that the industrial water in the second condensing heat exchange pipeline cools the water vapor in the first condensing heat exchange pipeline to form liquid coolant water, and the outlet of the second condensing heat exchange pipeline is connected with at least one of a water collecting well and a heating device;

[0014] A throttling valve or an expander is connected between the outlet of the first condensing heat exchange pipeline and the inlet of the first evaporating heat exchange pipeline, so as to reduce the pressure of the liquid coolant water, and the second evaporating heat exchange pipeline is connected in series in an indoor refrigeration circulation pipeline;

[0015] The outlet of the first evaporating heat exchange pipeline and the liquid return port of the first absorbing heat exchange pipeline are connected through a second water vapor pipeline; and the inlet of the second absorbing heat exchange pipeline is connected with a second industrial water pipeline.

[0016] In some embodiments, the lithium bromide solution circulation pipeline comprises a first circulation pipeline, a second circulation pipeline and a solution pump;

[0017] The first generating heat exchange pipeline, the first circulation pipeline, the first absorbing heat exchange pipeline and the second circulation pipeline are connected in series, and the solution pump is arranged in the first circulation pipeline or the second circulation pipeline.

[0018] In some embodiments, further comprising:

[0019] A solution heat exchanger comprises a first solution heat exchange pipeline and a second solution heat exchange pipeline which exchange heat with each other;

[0020] The first solution heat exchange pipeline is connected in series in the first circulation pipeline, and the second solution heat exchange pipeline is connected in series in the second circulation pipeline.

[0021] In some embodiments, the outlet of the second absorbing heat exchange pipeline is connected to the first industrial water pipeline.

[0022] In some embodiments, the outlet of the second condensing heat exchange pipeline is connected to the water collecting well through a first switching pipeline, and the first switching pipeline is provided with a first valve.

[0023] The outlet of the second condensing heat exchange pipeline is connected to the heating device through a second switching pipeline, and the second switching pipeline is provided with a second valve.

[0024] In some embodiments, further comprising:

[0025] a water pumping pipeline,

[0026] The water pumping pipeline connects the water collecting well and a furnace top water seal tank of the dry quenching boiler.

[0027] In some embodiments, the heating device is a heating device of a station building.

[0028] In some embodiments, the indoor refrigeration circulation pipeline is an indoor refrigeration circulation pipeline of a boiler instrument room and a process room of an electrical room.

[0029] In some embodiments, the indoor refrigeration circulation pipeline comprises a circulating cold pipeline, a circulating pump and heat exchange circulating liquid arranged in the circulating cold pipeline, the second evaporating heat exchange pipeline is connected in series to the circulating cold pipeline, the circulating pump is arranged in the circulating cold pipeline to drive the heat exchange circulating liquid to circulate in the series-connected circulating cold pipeline and the second evaporating heat exchange pipeline, and at least part of the circulating cold pipeline is arranged in the boiler instrument room and the process room of the electrical room.

[0030] In some embodiments, the outlet of the second generating heat exchange pipeline is connected to a desalted water tank or an oxygen remover.

[0031] The embodiments of the present application have the following beneficial effects:

[0032] The dry quenching boiler secondary steam waste heat recycling device provided by the embodiment of the present application comprises a generator, a condenser, an evaporator, an absorber, a lithium bromide solution circulation pipeline and a continuous blowdown expander. The generator comprises first and second generation heat exchange pipelines that are in heat exchange with each other; the condenser comprises first and second condensation heat exchange pipelines that are in heat exchange with each other; the evaporator comprises first and second evaporation heat exchange pipelines that are in heat exchange with each other; the absorber comprises first and second absorption heat exchange pipelines that are in heat exchange with each other; the first generation heat exchange pipeline and the first absorption heat exchange pipeline are connected in series to the lithium bromide solution circulation pipeline, wherein the first generation heat exchange pipeline is provided with a steam outlet for discharging water vapor, and the first absorption heat exchange pipeline is provided with a liquid return port; the inlet of the second generation heat exchange pipeline is connected to the secondary steam exhaust port of the continuous blowdown expander, the water vapor generated by the lithium bromide solution in the first generation heat exchange pipeline and the second generation heat exchange pipeline is transported to the first condensation heat exchange pipeline through a first water vapor pipeline; the inlet of the second condensation heat exchange pipeline is connected to a first industrial water pipeline, and the outlet of the second condensation heat exchange pipeline is connected to at least one of a water collecting well and a heating device; a throttling valve or an expander is connected between the outlet of the first condensation heat exchange pipeline and the inlet of the first evaporation heat exchange pipeline, so as to reduce the pressure of the liquid refrigerant water; the second evaporation heat exchange pipeline is connected in series to an indoor refrigeration cycle pipeline; the liquid refrigerant water in the first evaporation heat exchange pipeline and the first evaporation heat exchange pipeline are heat exchanged, and then transported to the first absorption heat exchange pipeline through a second water vapor pipeline, and mixed with the concentrated lithium bromide solution in the first absorption heat exchange pipeline; the inlet of the second absorption heat exchange pipeline is connected to a second industrial water pipeline, for heat exchange with the lithium bromide solution in the first absorption heat exchange pipeline to cool the lithium bromide solution.

[0033] The technical scheme provided by the embodiment of the present application utilizes the low-grade waste heat of the secondary steam discharged by the continuous blowdown expander of the dry quenching boiler under the premise of safe and stable operation of the dry quenching system, converts the recovered waste heat into cold energy, and provides cold energy for process rooms such as the boiler instrument room and the comprehensive electrical room that need to be cooled to achieve cooling; in winter, while providing cooling for process rooms such as the boiler instrument room and the comprehensive electrical room that need to be cooled, the industrial water flowing through the absorber and the condenser is used to heat the dry quenching boiler and other station buildings. Thus, effective energy conversion and cascade utilization are achieved, and the system realizes efficient energy allocation throughout the year. The embodiment of the present application not only significantly improves the energy comprehensive utilization efficiency of the entire dry quenching production process, reduces the operation cost, but also creates considerable economic benefits, and has important popularization value and application prospect.

[0034] Of course, implementing any product or method of the present application does not necessarily require achieving all the advantages described above at the same time. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only constitute some embodiments of the present application, and other embodiments can also be obtained by those skilled in the art based on these drawings.

[0036] Figure 1 A pipeline arrangement schematic diagram of a dry quenching coke oven boiler secondary steam waste heat recovery and utilization device provided for an embodiment of the present application.

[0037] The reference signs are as follows:

[0038] Generator 11, condenser 12, evaporator 13, absorber 14, lithium bromide solution circulation pipeline 15, first circulation pipeline 151, second circulation pipeline 152, solution pump 153, continuous blowdown expander 16, first water vapor pipeline 171, throttling valve 172, second water vapor pipeline 173, first industrial water pipeline 181, second industrial water pipeline 182, water collecting well 191, heating device 192, first switching pipeline 193, first valve 194, second switching pipeline 195, second valve 196, water pumping pipeline 197, furnace top water seal tank 198, indoor refrigeration circulation pipeline 20, circulating cold pipe 201, circulating pump 202, solution heat exchanger 21, process room 100. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments only constitute some embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art based on the present application belong to the scope of protection of the present application.

[0040] In the dry quenching coke oven boiler waste heat utilization system, if the secondary steam generated by the continuous blowdown expander 16 is directly discharged, it will result in waste of high-quality heat energy. Among them, the heat energy of the secondary steam is not effectively recovered and utilized, thereby reducing the overall heat recovery efficiency of the system.

[0041] In order to improve the overall heat recovery efficiency of the system, the present application provides a dry quenching coke oven boiler secondary steam waste heat recovery and utilization device, Figure 1 A pipeline arrangement schematic diagram of a dry quenching coke oven boiler secondary steam waste heat recovery and utilization device provided for an embodiment of the present application, Figure 1 As shown, the dry quenching coke oven boiler secondary steam waste heat recovery and utilization device comprises: a generator 11, a condenser 12, an evaporator 13, an absorber 14, a lithium bromide solution circulation pipeline 15, and a continuous blowdown expander 16.

[0042] The generator 11 comprises first and second heat exchange pipes for heat exchange with each other; the condenser 12 comprises first and second heat exchange pipes for heat exchange with each other; the evaporator 13 comprises first and second heat exchange pipes for heat exchange with each other; the absorber 14 comprises first and second heat exchange pipes for heat exchange with each other; the first heat exchange pipe and the first heat exchange pipe are connected in series in the lithium bromide solution circulation pipe 15, wherein the first heat exchange pipe has a steam outlet for discharging water vapor, and the first heat exchange pipe has a return liquid port; the continuous blowdown expander 16 is connected to the inlet of the second heat exchange pipe through the secondary steam outlet, so that the lithium bromide solution in the first heat exchange pipe and the second heat exchange pipe are heat exchanged to generate water vapor; the steam outlet of the first heat exchange pipe and the steam inlet of the first condensation heat exchange pipe are connected through the first water vapor pipe 171; the inlet of the second condensation heat exchange pipe is connected to the first industrial water pipe 181, so that the industrial water in the second condensation heat exchange pipe cools the water vapor in the first condensation heat exchange pipe to form liquid coolant water, and the outlet of the second condensation heat exchange pipe is connected to at least one of the water collecting well 191 and the heating device 192; the outlet of the first condensation heat exchange pipe and the inlet of the first evaporation heat exchange pipe are connected through a throttling valve 172 to reduce the pressure of the liquid coolant water, and the second evaporation heat exchange pipe is connected in series to the indoor refrigeration circulation pipe 20; the outlet of the first evaporation heat exchange pipe and the return liquid port of the first absorption heat exchange pipe are connected through the second water vapor pipe 173; the inlet of the second absorption heat exchange pipe is connected to the second industrial water pipe 182.

[0043] The working principle of the dry quenching boiler secondary steam waste heat recovery and utilization device is as follows:

[0044] The lithium bromide solution circulates in the lithium bromide solution circulation pipe 15 and can flow to the first heat exchange pipe, the low-level heat source (such as 0.6 MPa, 160℃ secondary steam) discharged from the secondary steam outlet of the continuous blowdown expander 16 enters the second heat exchange pipe, and the lithium bromide solution and the low-level heat source are heat exchanged in the generator 11 (heat exchanged through the first heat exchange pipe and the second heat exchange pipe). Because the boiling point of lithium bromide is as high as 1265℃ at normal pressure, which is much higher than the boiling point of water (100℃), the lithium bromide solution absorbs heat in the generator 11, and water is analyzed to become high-pressure water vapor (for example, 100℃ to 130℃, 0.09MPa absolute atmospheric pressure), which is discharged from the steam outlet of the first heat exchange pipe, and the remaining concentrated lithium bromide solution continues to circulate in the lithium bromide solution circulation pipe 15 and is transported to the first absorption heat exchange pipe.

[0045] The industrial cold water of the first industrial water pipe 181 is sent into the second condensing heat exchange pipe, so that the water vapor of the first condensing heat exchange pipe and the industrial cold water of the first industrial water pipe 181 exchange heat in the condenser 12. The water vapor of the first condensing heat exchange pipe is condensed and liquefied, and releases heat to the industrial cold water of the first industrial water pipe 181 to form high-pressure liquid refrigerant water. The outlet of the second condensing heat exchange pipe is connected to at least one of the water collecting well 191 and the heating equipment 192, and the industrial cold water of the first industrial water pipe 181 is sent to the water collecting well 191 for water supplement or the heating equipment 192 for heating after being warmed, so as to be reused subsequently.

[0046] The liquid refrigerant water is sent to the first evaporating heat exchange pipe of the evaporator 13 after being depressurized and vaporized by the throttle valve 172. The liquid refrigerant water is depressurized and vaporized to form low-pressure steam (for example, 30-60°C, 0.0009 MPa absolute atmospheric pressure), which can absorb a large amount of heat (the boiling point of water becomes very low in a low-pressure environment, and a large amount of heat can be absorbed during evaporation, so that a refrigeration effect can be produced), so as to cool the second evaporating heat exchange pipe connected in series with the indoor refrigeration cycle pipe 20, and the heat exchange circulating liquid in the indoor refrigeration cycle pipe 20 can be cooled to about 7°, so as to provide cold energy for indoor cooling, and the refrigeration purpose of the room is achieved.

[0047] The low-pressure water vapor is sent to the first absorbing heat exchange pipe of the absorber 14 through the second water vapor pipe 173, and is mixed with the above-mentioned concentrated lithium bromide solution. The industrial cold water of the second industrial water pipe 182 is sent into the second absorbing heat exchange pipe, so that the industrial cold water of the second absorbing heat exchange pipe and the mixed lithium bromide solution exchange heat, and the mixed lithium bromide solution is cooled, so as to facilitate the low-temperature lithium bromide solution to absorb more heat in the generator 11.

[0048] The lithium bromide solution circulating pipe 15 is a pipe system for circulating the lithium bromide solution, and a solution pump 153 can be used to realize the circulation of the lithium bromide solution in the first generating heat exchange pipe, the lithium bromide solution circulating pipe 15 and the first absorbing heat exchange pipe connected in series.

[0049] The high-pressure water vapor separated out after the lithium bromide solution absorbs heat in the generator 11 is returned to the first absorbing heat exchange pipe after exchanging heat in the first condensing heat exchange pipe and the first evaporating heat exchange pipe in sequence, and is mixed with the remaining lithium bromide solution (lithium bromide is a strong hygroscopic agent, and the water vapor partial pressure of its aqueous solution is very low, which can strongly absorb the surrounding water vapor. The higher the concentration of the lithium bromide solution, the stronger the water vapor absorption capacity), so as to form a complete closed loop circulation of the lithium bromide solution in the dry quenching boiler secondary steam waste heat recovery and utilization device.

[0050] The absorption cycle of the dry quenching boiler secondary steam waste heat recovery device is as follows: in the absorber 14, the lithium bromide absorbs the low-pressure refrigerant steam from the evaporator 13 to become a refrigerant-absorbent binary solution (dilute lithium bromide solution) with a higher concentration of refrigerant, which is sent to the generator 11 through the solution pump 153 after being pressurized. In the generator 11, an external high-temperature heat source (secondary steam output by the continuous blowdown expander 16) provides heat to the binary solution, causing a large amount of refrigerant in the binary solution to vaporize into high-pressure high-temperature gaseous refrigerant. The high-pressure high-temperature gaseous refrigerant goes to the condenser 12, and the remaining binary solution with a lower concentration of refrigerant (concentrated lithium bromide solution) returns to the absorber 14, forming a complete closed loop cycle of lithium bromide solution in the dry quenching boiler secondary steam waste heat recovery device.

[0051] The dry quenching boiler secondary steam waste heat recovery device of the present embodiment uses the secondary steam generated by the continuous blowdown expander 16 of the dry quenching boiler as a heat source to evaporate the water in the dilute lithium bromide solution in the generator 11 to become a concentrated solution, and the high-pressure water vapor evaporated in the condenser 12 is used to heat industrial water, so that the high-temperature industrial water can be used by the heating equipment 192 in winter (for example, the heating equipment 192 is the heating equipment of the dry quenching boiler station house and other station houses), or used to supplement the water in the water collection well 191 in the non-heating season, which can be used for water sealing of the dry quenching boiler's furnace top water sealing tank 198, etc. In the evaporator 13, the liquid refrigerant water is rapidly evaporated at very low pressure, absorbs the heat of the heat exchange circulating liquid flowing through the evaporator pipe, and thus produces low-temperature heat exchange circulating liquid (such as cold water) for the indoor refrigeration cycle pipeline 20, so as to provide cold energy for the process room 100 of the boiler instrument room and the electrical room. In the absorber 14, the low-temperature water vapor from the evaporator 13 is strongly absorbed by the concentrated lithium bromide solution sent from the generator 11 to become a dilute solution, and the heat released during the absorption process is taken away by the industrial cold water.

[0052] In some embodiments of the present application, the outlet of the second absorption heat exchange pipeline is connected to the first industrial water pipe 181. According to the scheme of the present application, the inlet of the second absorption heat exchange pipeline is connected to the second industrial water pipe 182, and by connecting the outlet of the second absorption heat exchange pipeline to the first industrial water pipe 181, the industrial cold water in the second industrial water pipe 182 is heated after completing the cooling of the lithium bromide solution, and the heated industrial cold water flows to the first industrial water pipe 181 as the cooling water source of the condenser 12. The industrial cold water is heated twice, once in the absorber 14 and once in the condenser 12, so that a higher quality heat source can be provided for the heating equipment 192.

[0053] The technical scheme provided by the embodiments of the present application utilizes the low-grade waste heat of the secondary steam discharged by the continuous blowdown expander 16 of the dry quenching boiler under the premise of safe and stable operation of the dry quenching system, converts the recovered waste heat into cold energy, and realizes cooling of the process room 100 requiring cooling, such as the boiler instrument room and the comprehensive electrical room, by the cold energy; in winter, the dry quenching boiler and other station buildings are heated by the industrial water flowing through the absorber 14 and the condenser 12 while the process room 100 requiring cooling, such as the boiler instrument room and the comprehensive electrical room, is cooled. Thus, effective energy conversion and cascade utilization are realized, and the system realizes efficient energy allocation throughout the year. The embodiments of the present application not only significantly improve the energy comprehensive utilization efficiency of the entire dry quenching production process, reduce the operation cost, but also create considerable economic benefits, and have important popularization value and application prospect.

[0054] Specifically, the indoor refrigeration cycle pipeline 20 comprises: a circulating cold pipe 201, a circulating pump 202, and heat exchange circulating liquid arranged in the circulating cold pipe 201. The second evaporation heat exchange pipeline is connected in series with the circulating cold pipe 201, and the circulating pump 202 is arranged in the circulating cold pipe 201 to drive the heat exchange circulating liquid to circulate in the series-connected circulating cold pipe 201 and second evaporation heat exchange pipeline. At least part of the circulating cold pipe 201 is arranged in the process room 100 of the boiler instrument room and the electrical room.

[0055] During the circulation of the heat exchange circulating liquid in the series-connected circulating cold pipe 201, the heat exchange circulating liquid can form 7℃ or so after being cooled by the low-pressure steam formed by the pressure reduction vaporization of the liquid refrigerant water in the evaporator 13 and circulating to the section of the circulating cold pipe 201 in the process room 100, thereby cooling the process room 100.

[0056] In a specific implementation, the low-pressure steam of the first evaporation heat exchange pipeline can be sprayed on the second evaporation heat exchange pipeline through a spraying device, and heat exchanged with the heat exchange circulating liquid circulating in the second evaporation heat exchange pipeline.

[0057] In some embodiments of the present application, the outlet of the second evaporation heat exchange pipeline can be connected to a demineralized water tank. The demineralized water tank is a container for recovering the condensate water generated after the steam turbine generator generates electricity, and the condensate water discharged by the second evaporation heat exchange pipeline can be recovered to the demineralized water tank, so as to recycle the condensate water cooled by the secondary steam.

[0058] Alternatively, the outlet of the second evaporation heat exchange pipeline can be connected to a deaerator. The condensate water discharged by the second evaporation heat exchange pipeline can be recovered to the deaerator, so as to recycle the condensate water cooled by the secondary steam.

[0059] The condensed water generated after the secondary steam is cooled is returned to a desalted water tank or an oxygen remover of the dry quenching system, so that the condensed water is recycled.

[0060] Specifically, the lithium bromide solution circulation pipeline 15 can include a first circulation pipeline 151, a second circulation pipeline 152, and a solution pump 153; the first circulation pipeline 151, the first absorption heat exchange pipeline, and the second circulation pipeline 152 are sequentially connected in series, and the solution pump 153 is arranged in the first circulation pipeline 151 or the second circulation pipeline 152.

[0061] The scheme of the present application divides the lithium bromide solution circulation pipeline 15 into the first circulation pipeline 151 and the second circulation pipeline 152, and arranges the solution pump 153 in the first circulation pipeline 151 or the second circulation pipeline 152, so that the lithium bromide solution flows to the absorber 14 for heat exchange after being heated in the generator 11, and the diluted solution flows back to the generator 11 through the second circulation pipeline 152 after being diluted in the absorber 14, forming a closed cycle.

[0062] In actual application, in some embodiments of the present application, the lithium bromide solution circulation pipeline 15 is used to realize the circulation of the solution, however, in the implementation process, the heat carried by the high-temperature concentrated solution flowing from the generator 11 to the absorber 14 is not effectively utilized, and the low-temperature dilute solution flowing back from the absorber 14 to the generator 11 needs to be additionally heated, resulting in serious heat loss of the system, reduced energy utilization rate, and restricted overall operation efficiency.

[0063] Some embodiments of the present application also include a solution heat exchanger 21, which includes a first solution heat exchange pipeline and a second solution heat exchange pipeline that exchange heat with each other; the first solution heat exchange pipeline is connected in series with the first circulation pipeline 151, and the second solution heat exchange pipeline is connected in series with the second circulation pipeline 152.

[0064] The scheme of the present application connects the first solution heat exchange pipeline in series with the first circulation pipeline 151, so that the high-temperature concentrated solution flowing out of the generator 11 is pre-cooled by flowing through the first solution heat exchange pipeline and reversely exchanging heat with the low-temperature dilute solution in the second solution heat exchange pipeline during the process of flowing to the absorber 14; at the same time, the second solution heat exchange pipeline is connected in series with the second circulation pipeline 152, so that the low-temperature dilute solution returning from the absorber 14 is pre-heated by flowing through the second solution heat exchange pipeline and exchanging heat with the high-temperature concentrated solution during the process of flowing to the generator 11. By pre-heating the dilute solution and pre-cooling the concentrated solution, the heat load of the generator 11 and the cooling water consumption of the absorber 14 are reduced, and the overall operation efficiency of the system is improved.

[0065] The industrial water is heated to 60-95℃ in the process of sequentially cooling the absorber 14 and the condenser 12. In winter, the hot water can be used as a heat medium to heat the quenching boiler and other adjacent station buildings. In summer, the industrial water is mixed with the quenching condensate water in the pipeline and sent to the water collecting well 191, and then is sent to the water seal tank 198 on the top of the furnace through the water collecting well 191, and is used for the liquid seal of the water seal tank 198 on the top of the furnace. In a specific implementation, the outlet of the second condensing heat exchange pipeline is connected to the water collecting well 191 through the first switching pipeline 193, and the first switching pipeline 193 is provided with a first valve 194; the outlet of the second condensing heat exchange pipeline is connected to the heating equipment 192 through the second switching pipeline 195, and the second switching pipeline 195 is provided with a second valve 196, and the water pumping pipeline 197 connects the water collecting well 191 and the water seal tank 198 on the top of the quenching boiler.

[0066] The first valve 194 and the second valve 196 are regulating devices for controlling the on-off of fluid, which can be realized by using an electric ball valve or a pneumatic butterfly valve.

[0067] In application, the flow direction of the condensate water is flexibly adjusted according to the actual working condition (such as seasonal change and fluctuation of heating demand), so as to improve the stability of the waste heat recovery efficiency. For example, in the non-heating season, the second valve 196 is closed, the first valve 194 is opened, the industrial water is introduced into the water collecting well 191, and then the water in the water collecting well 191 is introduced into the quenching professional water tank of the quenching boiler through the water pumping pipeline 197, and is used for the liquid seal of the water seal tank 198 on the top of the furnace. In the heating season, the first valve 194 is closed, the second valve 196 is opened, and the heated industrial water is introduced into the heating equipment 192 of the station building, so as to heat the station building.

[0068] In application, the water in the water collecting well 191 is not limited to be used for the liquid seal of the water seal tank 198 on the top of the furnace, but also can be used for other devices for cascade utilization, such as cleaning operation on the top platform of the quenching furnace.

[0069] In the embodiment of the present application, the evaporator 13, the condenser 12, the throttling valve 172, the generator 11, the absorber 14, the solution pump 153, the solution heat exchanger 21 and the industrial water pipeline (the first industrial water pipeline 181 and the second industrial water pipeline 182) utilize the low-grade heat energy in the continuous blowdown expander 16 of the quenching boiler for waste heat utilization, so as to improve the energy comprehensive utilization efficiency of the quenching process and reduce the operation cost.

[0070] In a specific implementation, an expander can also be used to replace the throttling valve 172, which can significantly improve the available expansion work of the quenching boiler secondary steam waste heat recovery device.

[0071] The above merely describes the preferred embodiments of the present application, but is not used to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A dry quenching boiler secondary steam waste heat recovery device, characterized in that, Comprise: a generator (11) comprising a first generator heat exchange pipeline and a second generator heat exchange pipeline which are in heat exchange with each other; a condenser (12) comprising a first condenser heat exchange pipeline and a second condenser heat exchange pipeline which are in heat exchange with each other; an evaporator (13) comprising a first evaporator heat exchange pipeline and a second evaporator heat exchange pipeline which are in heat exchange with each other; an absorber (14) comprising a first absorber heat exchange pipeline and a second absorber heat exchange pipeline which are in heat exchange with each other; a lithium bromide solution circulation pipeline (15), the first generator heat exchange pipeline and the first absorber heat exchange pipeline are connected in series in the lithium bromide solution circulation pipeline (15), wherein the first generator heat exchange pipeline has a steam outlet for discharging water vapor, and the first absorber heat exchange pipeline has a return liquid port; a continuous blowdown expander (16), a secondary steam exhaust port of which is connected to an inlet of the second generator heat exchange pipeline, so that the lithium bromide solution of the first generator heat exchange pipeline and the second generator heat exchange pipeline exchange heat to generate water vapor; a first water vapor pipeline (171) is connected between the steam outlet of the first generator heat exchange pipeline and the steam inlet of the first condenser heat exchange pipeline; an inlet of the second condenser heat exchange pipeline is connected to a first industrial water pipeline (181), so that the industrial water of the second condenser heat exchange pipeline cools the water vapor of the first condenser heat exchange pipeline to form liquid coolant water, and an outlet of the second condenser heat exchange pipeline is connected to at least one of a water collecting well (191) and a heating device (192); a throttling valve or an expander is connected between the outlet of the first condenser heat exchange pipeline and the inlet of the first evaporator heat exchange pipeline, so as to reduce the pressure of the liquid coolant water, and the second evaporator heat exchange pipeline is connected in series in a room air conditioning circulation pipeline (20); a second water vapor pipeline (173) is connected between the outlet of the first evaporator heat exchange pipeline and the return liquid port of the first absorber heat exchange pipeline; and an inlet of the second absorber heat exchange pipeline is connected to a second industrial water pipeline (182).

2. The dry quenching boiler secondary steam waste heat recovery and utilization device according to claim 1, wherein the lithium bromide solution circulation pipeline (15) comprises a first circulation pipeline (151), a second circulation pipeline (152), and a solution pump (153); the first generator heat exchange pipeline, the first circulation pipeline (151), the first absorber heat exchange pipeline, and the second circulation pipeline (152) are connected in series, and the solution pump (153) is arranged in the first circulation pipeline (151) or the second circulation pipeline (152). Further comprise: a solution heat exchanger (21) comprising a first solution heat exchange pipeline and a second solution heat exchange pipeline which are in heat exchange with each other; 3. The dry quenching boiler secondary steam waste heat recovery device according to claim 2, characterized in that, the first solution heat exchange pipeline is connected in series in the first circulation pipeline (151), and the second solution heat exchange pipeline is connected in series in the second circulation pipeline (152).

4. The dry quenching boiler secondary steam waste heat recovery and utilization device according to claim 1, wherein an outlet of the second absorber heat exchange pipeline is connected to the first industrial water pipeline (181).

5. The dry quenching boiler secondary steam waste heat recovery and utilization device according to claim 1, wherein ​ ​ ​ The outlet of the second condensing heat exchange pipeline is connected to the water collecting well (191) through a first switching pipeline (193) provided with a first valve (194); The outlet of the second condensing heat exchange pipeline is connected to the heating device (192) through a second switching pipeline (195) provided with a second valve (196).

6. The dry quenching boiler secondary steam waste heat recovery device according to claim 5, characterized in that, Further comprising: a water pumping pipeline (197), The water pumping pipeline (197) connects the water collecting well (191) and the dry quenching boiler's furnace top water seal tank (198).

7. The dry quenching boiler secondary steam waste heat recovery device according to claim 5, wherein The heating device (192) is a heating device (192) of a station building.

8. The dry quenching boiler secondary steam waste heat recovery device according to claim 1, wherein The indoor refrigeration circulation pipeline (20) is an indoor refrigeration circulation pipeline (20) of a boiler instrument room and a process room of an electrical room.

9. The dry quenching boiler secondary steam waste heat recovery device according to claim 8, wherein The indoor refrigeration circulation pipeline comprises a circulating cold pipeline, a circulating pump and heat exchange circulating liquid arranged in the circulating cold pipeline, the second evaporating heat exchange pipeline is connected in series to the circulating cold pipeline, the circulating pump is arranged in the circulating cold pipeline to drive the heat exchange circulating liquid to circulate in the series-connected circulating cold pipeline and the second evaporating heat exchange pipeline, and at least part of the circulating cold pipeline is arranged in the boiler instrument room and the process room of the electrical room.

10. The dry quenching boiler secondary steam waste heat recovery device according to claim 1, wherein The outlet of the second generating heat exchange pipeline is connected to a demineralized water tank or an oxygen remover.

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