CN117469839B - Overhead gas waste heat full recovery system and full recovery method - Google Patents
Overhead gas waste heat full recovery system and full recovery method Download PDFInfo
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- 239000007789 gas Substances 0.000 title claims abstract description 116
- 238000011084 recovery Methods 0.000 title claims abstract description 54
- 238000000034 method Methods 0.000 title claims abstract description 46
- 239000002918 waste heat Substances 0.000 title claims abstract description 43
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 110
- 239000007788 liquid Substances 0.000 claims abstract description 54
- 239000000498 cooling water Substances 0.000 claims abstract description 42
- 239000003507 refrigerant Substances 0.000 claims abstract description 36
- 238000010438 heat treatment Methods 0.000 claims abstract description 16
- 239000000463 material Substances 0.000 claims abstract description 15
- 238000000926 separation method Methods 0.000 claims description 31
- 239000012071 phase Substances 0.000 claims description 22
- 239000007791 liquid phase Substances 0.000 claims description 18
- 238000010992 reflux Methods 0.000 claims description 12
- 238000001704 evaporation Methods 0.000 claims description 9
- 230000008020 evaporation Effects 0.000 claims description 9
- 238000002309 gasification Methods 0.000 claims description 9
- 238000000605 extraction Methods 0.000 abstract description 3
- 239000000126 substance Substances 0.000 abstract description 3
- 238000001816 cooling Methods 0.000 description 31
- 230000008569 process Effects 0.000 description 18
- 238000005265 energy consumption Methods 0.000 description 7
- 238000005516 engineering process Methods 0.000 description 5
- 230000008901 benefit Effects 0.000 description 4
- 238000005260 corrosion Methods 0.000 description 3
- 230000007797 corrosion Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000011143 downstream manufacturing Methods 0.000 description 1
- 238000005194 fractionation Methods 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B27/00—Machines, plants or systems, using particular sources of energy
- F25B27/02—Machines, plants or systems, using particular sources of energy using waste heat, e.g. from internal-combustion engines
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B41/00—Fluid-circulation arrangements
- F25B41/30—Expansion means; Dispositions thereof
- F25B41/31—Expansion valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B41/00—Fluid-circulation arrangements
- F25B41/40—Fluid line arrangements
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B49/00—Arrangement or mounting of control or safety devices
- F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B7/00—Compression machines, plants or systems, with cascade operation, i.e. with two or more circuits, the heat from the condenser of one circuit being absorbed by the evaporator of the next circuit
Abstract
The invention provides a total recovery system and a total recovery method for waste heat of tower top gas, and relates to the field of heat recovery of chemical equipment, wherein the system comprises: the multi-flow heat exchange container comprises a high-temperature heat exchange unit and a low-temperature heat exchange unit; the high-temperature working medium evaporator is communicated with the top of the high-temperature heat exchange unit to receive heat medium water and evaporate the first refrigerant; the medium-temperature working medium condenser is connected with the bottom of the high-temperature working medium evaporator, and is used for heating the heat medium water and then conveying the heat medium water to the bottom of the high-temperature heat exchange unit for heat exchange; the high-temperature working medium condenser forms high-temperature heat exchange circulation with the high-temperature working medium evaporator and heats materials at the bottom of the tower-type vapor-liquid device; the medium temperature working medium evaporator forms medium temperature heat exchange circulation with the medium temperature working medium condenser, and conveys cooled cooling water to the bottom of the low temperature heat exchange unit for heat exchange; the invention can fully recover the residual heat of the tower top gas, has more stable system working state and higher heat utilization efficiency, and reduces the heat extraction cost.
Description
Technical Field
The invention relates to the field of heat recovery of chemical equipment, in particular to a total recovery system and a total recovery method for waste heat of tower top gas.
Background
In typical fractionation column processes, e.g. light hydrocarbon separation columns, CO 2 The bottom of the fractionating tower is usually heated by consuming a large amount of high-grade steam, and the problem of high energy consumption in operation generally exists, wherein the temperature of the gas phase at the top of the fractionating tower is about 70 ℃ to 120 ℃, the gas phase is usually cooled by air cooling or water cooling or air cooling and water cooling, a large amount of waste heat is not recovered, energy waste exists, and the energy consumption of air cooling or circulating water is increased. Currently, for existing technology air cooling or water cooling or air cooling plus water cooling processes, the following problems exist: on one hand, the waste heat of the tower top is not recovered, so that energy waste is caused; on the other hand, the problems of scaling and corrosion leakage of an air cooler and a water cooler frequently occur due to air cooling or water cooling in tower top cooling, shutdown and maintenance are needed when serious, long-period safe operation of the device is not facilitated, cooling difficulty is easy to occur particularly when the air temperature is high in summer, and the problems of high operation energy consumption or reduced treatment capacity caused by incapability of reaching process indexes or higher reflux temperature sometimes are solved, so that stable operation of the device is not facilitated.
In the existing energy-saving technology, a heat medium water heat exchanger or a process material heat exchanger is added before air cooling or water cooling or air cooling and water cooling, and the waste heat of a high-temperature section of the tower top gas is recovered to preheat the heat medium water or the process material. The method has the advantages that partial recovery of the waste heat of the tower top gas is realized, and the recovery cost is relatively low; the disadvantage is that the tower top gas after heat exchange by the heat medium water or the process material usually has the temperature of 60 ℃ to 90 ℃, the residual heat of the tower top gas is still partially not recovered, air cooling or water cooling is also required to be consumed for cooling, and meanwhile, the pressure drop of the tower top gas is increased due to the newly added heat medium water heat exchanger or process material heat exchanger, thereby causing adverse effect on the operation of the fractionating tower; meanwhile, although the air cooling or water cooling load is reduced, the water cooling or water cooling load still cannot be stopped, and the problems of scaling, corrosion leakage, difficulty in cooling in summer and the like of the water cooler still occur, so that the stable operation of the device is not facilitated.
Therefore, how to efficiently and fully utilize the waste heat resources of the tower top gas and completely disable air cooling or water cooling, not only ensures the stable operation of the device, but also fully utilizes the waste heat resources of the tower top, has important significance for reducing the energy consumption and carbon emission in the process of the fractionating tower and is a technical problem to be solved in the field.
Disclosure of Invention
Aiming at the problems in the prior art, the invention aims to provide a total recovery system and a total recovery method for the waste heat of the tower top gas, which overcome the difficulties in the prior art, can fully recover the waste heat of the tower top gas, has more stable working state of the system and higher heat utilization efficiency, and simultaneously reduces the heat taking cost.
According to one aspect of the present invention, there is provided a total recovery system for waste heat of overhead gas, comprising:
the multi-flow heat exchange container comprises a high-temperature heat exchange unit positioned at the upper part and a low-temperature heat exchange unit positioned at the lower part, wherein the high-temperature heat exchange unit receives tower top gas from the tower type vapor-liquid device and is communicated with the low-temperature heat exchange unit through an internal pipeline with a valve;
the gas-liquid separation tank is communicated with the lower part of the low-temperature heat exchange unit and is used for gas-liquid separation;
the high-temperature working medium evaporator is communicated with the top of the high-temperature heat exchange unit through a pipeline to receive heat medium water, and the first refrigerant is evaporated through the heat of the heat medium water;
the medium-temperature working medium condenser is connected with the bottom of the high-temperature working medium evaporator through a pipeline, and is used for heating the heat medium water and then conveying the heat medium water to the bottom of the high-temperature heat exchange unit to exchange heat with the tower top gas in the high-temperature heat exchange unit;
the high-temperature working medium condenser forms high-temperature heat exchange circulation with the high-temperature working medium evaporator through a pipeline with the first refrigerant, the first refrigerant after evaporation and gasification received from the high-temperature working medium evaporator is condensed, and the material at the bottom of the tower type vapor-liquid device is heated through a circulation pipeline; and
the medium temperature working medium evaporator is communicated with the top of the low temperature heat exchange unit through a pipeline, receives cooling water, evaporates the second refrigerant through the heat of the cooling water, conveys the cooled cooling water to the bottom of the low temperature heat exchange unit, exchanges heat with tower top gas in the low temperature heat exchange unit again, and the temperature of the heating medium water flowing out of the high temperature heat exchange unit is higher than that of the cooling water flowing out of the low temperature heat exchange unit.
Preferably, the method further comprises:
the heat medium water circulating pump is communicated with the high-temperature working medium evaporator and the medium-temperature working medium condenser, and the heat medium water flowing out of the high-temperature working medium evaporator is pressurized and then is conveyed to the medium-temperature working medium condenser; and
and the high-temperature working medium booster is communicated with the high-temperature working medium evaporator and the high-temperature working medium condenser, and is used for boosting the high-temperature working medium flowing out of the high-temperature working medium evaporator into a high-temperature high-pressure micro-overheat gas-phase working medium, and then the high-temperature high-pressure micro-overheat gas-phase working medium is conveyed to the high-temperature working medium condenser, wherein the temperature range of the high-temperature high-pressure micro-overheat gas-phase working medium is 100-135 ℃, and the pressure range is 1.5-3.0 Mpag.
Preferably, the method further comprises: the high-temperature working medium throttling expander is connected in series in a pipeline of the high-temperature working medium flowing from the high-temperature working medium condenser to the high-temperature working medium evaporator, so that the first refrigerant flowing into the high-temperature working medium evaporator is a low-temperature low-pressure liquid phase, the temperature range of the low-temperature low-pressure liquid phase is 50-75 ℃, and the pressure range is 0.35-0.7 Mpag.
Preferably, the method further comprises:
the cooling water circulating pump is communicated with the medium-temperature working medium evaporator and the low-temperature heat exchange unit, and the cooling water flowing out of the medium-temperature working medium evaporator is pressurized and then is conveyed to the low-temperature heat exchange unit; and
and the medium temperature working medium booster is communicated with the medium temperature working medium evaporator and the medium temperature working medium condenser, and the medium temperature working medium flowing out of the medium temperature working medium evaporator is boosted into a high-temperature high-pressure micro-overheat gas phase working medium and then is conveyed to the medium temperature working medium condenser, wherein the temperature range of the high-temperature high-pressure micro-overheat gas phase working medium is 60-90 ℃, and the pressure range is 2.5-5.2 Mpa.
Preferably, the method further comprises: and the medium temperature working medium throttling expander is connected in series with a pipeline of the medium temperature working medium condenser flowing to the medium temperature working medium evaporator, so that the second refrigerant flowing into the medium temperature working medium evaporator is a low-temperature low-pressure liquid phase, the temperature range of the low-temperature low-pressure liquid phase is 20-35 ℃, and the pressure range is 0.8-1.5 Mpag.
Preferably, the tower type vapor-liquid device is a fractionating tower, the top of the vapor-liquid separation tank is communicated with a vapor phase downstream pipeline, and the bottom of the vapor-liquid separation tank is communicated with a liquid phase return pipeline or an external pipeline through a return conveying pump.
Preferably, the method further comprises:
the first valve is connected in series with a pipeline between the high-temperature heat exchange unit and the low-temperature heat exchange unit; and
the first temperature sensor is arranged in the high-temperature heat exchange unit and connected with the first valve, detects the first temperature of the heat medium water, and opens the first valve when the first temperature of the heat medium water is higher than a first preset temperature threshold value, so that the tower top gas after heat exchange flows to the low-temperature heat exchange unit.
Preferably, the method further comprises:
the second valve is connected in series with a pipeline between the low-temperature heat exchange unit and the gas-liquid separation tank; and
the second temperature sensor is arranged on the low-temperature heat exchange unit and connected with the second valve, the second temperature sensor detects the temperature of the tower top gas, and when the temperature of the tower top gas is lower than a second preset temperature threshold value, the second valve is opened, so that the tower top gas subjected to heat exchange again flows to the gas-liquid separation tank.
Preferably, the tower top temperature of the tower type vapor-liquid device ranges from 70 ℃ to 120 ℃, and the tower bottom temperature ranges from 80 ℃ to 130 ℃;
the temperature of the water flowing into the low-temperature heat exchange unit is 30-40 ℃, and the temperature of the water flowing out of the low-temperature heat exchange unit is 40-50 ℃;
the water feeding temperature of the heat medium water flowing into the high-temperature heat exchange unit ranges from 50 ℃ to 80 ℃, and the water returning temperature of the heat medium water flowing out of the high-temperature heat exchange unit ranges from 60 ℃ to 90 ℃.
According to another aspect of the present invention, the present invention also provides a total recovery method of residual heat from overhead gas, using the aforementioned total recovery system of residual heat from overhead gas, comprising the steps of:
the high-temperature heat exchange unit receives tower top gas of the tower type vapor-liquid device, receives heat medium water of the high-temperature heat exchange unit through the high-temperature working medium evaporator, and evaporates a first refrigerant through heat of the heat medium water to form a first heat exchange cycle;
the first refrigerant which is received from the high-temperature working medium evaporator after evaporation and gasification is condensed through the high-temperature working medium condenser, and materials at the bottom of the tower type vapor-liquid device are heated through a circulating pipeline to form a second heat exchange cycle;
the low-temperature heat exchange unit receives the tower top gas flowing out of the high-temperature heat exchange unit, receives cooling water of the low-temperature heat exchange unit through a medium-temperature working medium evaporator, and evaporates a second refrigerant through heat of the cooling water to form a third heat exchange cycle;
the second refrigerant which is received from the medium temperature working medium evaporator after evaporation and gasification is condensed through the medium temperature working medium condenser, so as to form a fourth heat exchange cycle; and
and heating the heat medium water by the heat of the second refrigerant, and then conveying the heat medium water to the bottom of the high-temperature heat exchange unit to form a fifth heat exchange cycle.
Preferably, the method further comprises: detecting a first temperature of heat medium water in the high-temperature heat exchange unit in real time, judging whether the first temperature is higher than a first preset temperature threshold value, if yes, communicating the high-temperature heat exchange unit with the low-temperature heat exchange unit, and enabling the tower top gas after heat exchange to flow to the low-temperature heat exchange unit; if not, the high-temperature heat exchange unit and the low-temperature heat exchange unit are cut off, so that the tower top gas continuously exchanges heat with the heat medium water.
Preferably, the method further comprises: detecting a second temperature of the tower top gas in the low-temperature heat exchange unit in real time, judging whether the second temperature is lower than a second preset temperature threshold value, and if yes, communicating the low-temperature heat exchange unit with the gas-liquid separation tank; if not, stopping the low-temperature heat exchange unit and the gas-liquid separation tank to enable the tower top gas to continuously exchange heat with the cooling water.
Based on the technical characteristics, compared with the prior art, the invention has the following technical effects:
1. the residual heat of the tower top gas is completely recovered, and the air cooling and the water cooling can be completely stopped, so that the problems of scaling, corrosion leakage and difficult cooling in summer of the water cooler are thoroughly solved;
2. the waste heat of the tower top gas is taken out in a cascade utilization mode, so that the heat taking cost is lower and the efficiency is higher;
3. the waste heat of the tower top gas is transferred to a heat medium water system, and then is directly used for reboiling and heating the tower bottom material flow through waste heat upgrading and utilization, and a semi-open type waste heat upgrading and utilization flow is adopted, so that the heat utilization efficiency is higher, and the heat loss and investment are reduced;
4. the fluctuation resistance of the heat medium water system is stronger, the control operation is more stable, and the waste heat upgrading efficiency is higher;
5. the tower top gas adopts a multi-flow heat exchange container for heat recovery, the multi-flow heat exchange container adopts a vertical structure, the site occupation is smaller, the tower top gas is specially designed through a runner of the efficient heat exchange system, the heat exchange pressure drop is lower, and the operation energy consumption is smaller.
The invention can fully recover the residual heat of the tower top gas, the working state of the system is more stable, the heat utilization efficiency is higher, and the heat extraction cost is reduced.
For a further understanding of the nature and technical aspects of the present application, reference should be made to the following detailed description and accompanying drawings, which are included herein by way of illustration only and not by way of any limitation with respect to the scope of the claims.
Drawings
The above and other features and advantages of the present application will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings.
Fig. 1 is a schematic diagram of the total recovery system of residual heat from overhead gas of the present invention.
Reference numerals
1. Fractionating tower
2. Multi-flow heat exchange container
21. High-temperature heat exchange unit
22. Low-temperature heat exchange unit
3. Gas-liquid separation tank
4. Reflux delivery pump
5. Cooling water circulating pump
6. Medium temperature working medium evaporator
7. Medium temperature working medium booster
8. Medium temperature working medium condenser
9. Medium temperature working medium throttling expander
10. Heat medium water circulating pump
11. High-temperature working medium evaporator
12. High-temperature working medium supercharger
13. High-temperature working medium condenser
14. High-temperature working medium throttling expander
Detailed Description
Other advantages and effects of the present application will be readily apparent to those skilled in the art from the present disclosure, by describing embodiments of the present application with specific examples. The present application may be embodied or applied in other specific forms and details, and various modifications and alterations may be made to the details of the present application from different points of view and application without departing from the spirit of the present application. It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other.
The embodiments of the present application will be described in detail below with reference to the drawings so that those skilled in the art to which the present application pertains can easily implement the same. This application may be embodied in many different forms and is not limited to the embodiments described herein.
In the description of the present application, reference to the terms "one embodiment," "some embodiments," "examples," "particular examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the various embodiments or examples, and features of the various embodiments or examples, presented herein may be combined and combined by those skilled in the art without conflict.
Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the context of the present application, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.
For the purpose of clarity of the description of the present application, components that are not related to the description are omitted, and the same or similar components are given the same reference numerals throughout the description.
Throughout the specification, when a device is said to be "connected" to another device, this includes not only the case of "direct connection" but also the case of "indirect connection" with other elements interposed therebetween. In addition, when a certain component is said to be "included" in a certain device, unless otherwise stated, other components are not excluded, but it means that other components may be included.
When a device is said to be "on" another device, this may be directly on the other device, but may also be accompanied by other devices therebetween. When a device is said to be "directly on" another device in contrast, there is no other device in between.
Although the terms first, second, etc. may be used herein to connote various elements in some instances, the elements should not be limited by the terms. These terms are only used to distinguish one element from another element. For example, a first interface, a second interface, etc. Furthermore, as used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context indicates otherwise. It will be further understood that the terms "comprises," "comprising," "includes," and/or "including" specify the presence of stated features, steps, operations, elements, components, items, categories, and/or groups, but do not preclude the presence, presence or addition of one or more other features, steps, operations, elements, components, items, categories, and/or groups. The terms "or" and/or "as used herein are to be construed as inclusive, or meaning any one or any combination. Thus, "A, B or C" or "A, B and/or C" means "any of the following: a, A is as follows; b, a step of preparing a composite material; c, performing operation; a and B; a and C; b and C; A. b and C). An exception to this definition will occur only when a combination of elements, functions, steps or operations are in some way inherently mutually exclusive.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the language clearly indicates the contrary. The meaning of "comprising" in the specification is to specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but does not preclude the presence or addition of other features, regions, integers, steps, operations, elements, and/or components.
Although not differently defined, including technical and scientific terms used herein, all terms have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The term addition defined in the commonly used dictionary is interpreted as having a meaning conforming to the contents of the related art document and the current hint, so long as no definition is made, it is not interpreted as an ideal or very formulaic meaning too much.
Fig. 1 is a schematic diagram of the total recovery system of residual heat from overhead gas of the present invention. As shown in fig. 1, the present invention provides a total recovery system for waste heat of overhead gas, comprising: a multi-flow heat exchange container 2, a gas-liquid separation tank 3, a high-temperature working medium evaporator 11, a medium-temperature working medium condenser 8, a high-temperature working medium condenser 13 and a medium-temperature working medium evaporator 6. The multi-flow heat exchange container 2 comprises a high-temperature heat exchange unit 21 positioned at the upper part and a low-temperature heat exchange unit 22 positioned at the lower part, wherein the high-temperature heat exchange unit 21 receives tower top gas from the tower type vapor-liquid device and is communicated with the low-temperature heat exchange unit 22 through an internal pipeline with a valve. The gas-liquid separation tank 3 is communicated with the lower part of the low-temperature heat exchange unit 22, and performs gas-liquid separation. The high-temperature working medium evaporator 11 is communicated with the top of the high-temperature heat exchange unit 21 through a pipeline to receive heat medium water, and evaporates the first refrigerant through heat of the heat medium water. The medium temperature working medium condenser 8 is connected with the bottom of the high temperature working medium evaporator 11 through a pipeline, heats the heat medium water and then conveys the heat medium water to the bottom of the high temperature heat exchange unit 21, and exchanges heat with the tower top gas in the high temperature heat exchange unit 21. The high-temperature working medium condenser 13 forms a high-temperature heat exchange cycle with the high-temperature working medium evaporator 11 through a pipeline with a first refrigerant, the first refrigerant after evaporation and gasification received from the high-temperature working medium evaporator 11 is condensed, and materials at the bottom of the tower type vapor-liquid device are heated through a circulating pipeline. The medium temperature working medium evaporator 6 forms medium temperature heat exchange circulation with the medium temperature working medium condenser 8 through a pipeline with a second refrigerant, heats the heat medium water through the heat of the medium temperature working medium, the medium temperature working medium evaporator 6 is communicated with the top of the low temperature heat exchange unit 22 through the pipeline to receive cooling water, evaporates the second refrigerant through the heat of the cooling water, conveys the cooled cooling water to the bottom of the low temperature heat exchange unit 22, exchanges heat with the top gas in the low temperature heat exchange unit 22 again, and the temperature of the heat medium water flowing out of the high temperature heat exchange unit 21 is higher than the temperature of the cooling water flowing out of the low temperature heat exchange unit 22. The invention provides a total recovery, upgrading and utilizing system for waste heat of tower top gas, which adopts a multi-flow heat exchange container to take out the waste heat of the tower top gas in a grading manner according to a waste heat cascade utilization principle, wherein the tower top gas sequentially passes through a high temperature section and a low temperature Duan Jiangwen, the low temperature section takes out the waste heat of the tower top gas after heat exchange of the high temperature section through cooling water, heat is transferred to heating medium water after primary upgrading, the heating medium water directly exchanges heat with the tower top gas through the high temperature section to take out the waste heat completely, and finally, the heating medium water waste heat is upgraded and is directly used as a tower bottom reboiler heating source, so that the tower bottom heating steam consumption is finally reduced, and the energy consumption of a fractionating tower is reduced. The "high temperature" and "low temperature" in the names of the parts of the present invention are not limited to specific temperature ranges, but each part of the "high temperature" in the names mainly cooperates with the high temperature heat exchange unit 21 for performing the first heat exchange in the multi-stream heat exchange container 2, and each part of the "low temperature" in the names mainly cooperates with the low temperature heat exchange unit 22 for performing the second heat exchange in the multi-stream heat exchange container 2, which is the relative temperature level under two working environments, and will not be repeated herein.
In a preferred embodiment, a hot medium water circulation pump 10 and a hot medium booster 12 are also included. The heat medium water circulating pump 10 is communicated with the high-temperature working medium evaporator 11 and the medium-temperature working medium condenser 8, and the heat medium water flowing out of the high-temperature working medium evaporator 11 is pressurized and then is conveyed to the medium-temperature working medium condenser 8. The high-temperature working medium booster 12 is connected with the high-temperature working medium evaporator 11 and the high-temperature working medium condenser 13, boosts the high-temperature working medium flowing out of the high-temperature working medium evaporator 11 into a high-temperature high-pressure micro-overheat gas-phase working medium, and then transmits the high-temperature high-pressure micro-overheat gas-phase working medium to the high-temperature working medium condenser 13, wherein the temperature range of the high-temperature high-pressure micro-overheat gas-phase working medium is 100 ℃ to 135 ℃, and the pressure range is 1.5Mpag to 3.0Mpag, but the invention is not limited thereto.
In a preferred embodiment, further comprising: a high temperature working medium throttling expander 14 connected in series in the pipeline of the high temperature working medium flowing from the high temperature working medium condenser 13 to the high temperature working medium evaporator 11, so that the first refrigerant flowing into the high temperature working medium evaporator 11 is a low temperature low pressure liquid phase, the temperature range of the low temperature low pressure liquid phase is 50 ℃ to 75 ℃, and the pressure range is 0.35Mpag to 0.7Mpag, but not limited thereto. The high-temperature working medium is throttled and expanded by the high-temperature working medium throttle expander 14, and the throttle expansion process (Throttling Expansion Process) refers to a process of adiabatic expansion of fluid (gas or liquid) at higher pressure to a lower pressure direction through a porous plug (or a throttle valve). Thermal expansion refers to the fact that no heat exchange exists between the gas and the outside, but the gas does work on the outside, and the gas expands, and therefore, the description is omitted.
In a preferred embodiment, a cooling water circulation pump 5 and a medium temperature working medium booster 7 are also included. The cooling water circulating pump 5 is communicated with the medium temperature working medium evaporator 6 and the low temperature heat exchange unit 22, and the cooling water flowing out of the medium temperature working medium evaporator 6 is pressurized and then is conveyed to the low temperature heat exchange unit 22. The medium temperature working medium booster 7 is communicated with the medium temperature working medium evaporator 6 and the medium temperature working medium condenser 8, and the medium temperature working medium flowing out of the medium temperature working medium evaporator 6 is boosted into a high-temperature high-pressure micro-overheat gas phase working medium and then is conveyed to the medium temperature working medium condenser 8, wherein the temperature range of the high-temperature high-pressure micro-overheat gas phase working medium is 60-90 ℃, and the pressure range is 2.5-5.2 Mpag, but the method is not limited thereto.
In a preferred embodiment, further comprising: and a medium temperature working medium throttling expander 9 connected in series with the medium temperature working medium condenser 8 and flowing into the pipeline of the medium temperature working medium evaporator 6, so that the second refrigerant flowing into the medium temperature working medium evaporator 6 is a low-temperature low-pressure liquid phase, the temperature range of the low-temperature low-pressure liquid phase is 20-35 ℃, and the pressure range is 0.8-1.5 Mpag, but the invention is not limited thereto. The medium temperature working medium throttling expander 9 is used for throttling expansion of the medium temperature working medium, and the throttling expansion process (Throttling Expansion Process) refers to the adiabatic expansion process of fluid (gas or liquid) under higher pressure to a lower pressure direction through a porous plug (or a throttling valve). Thermal expansion refers to the fact that no heat exchange exists between the gas and the outside, but the gas does work on the outside, and the gas expands, and therefore, the description is omitted.
In a preferred embodiment, the tower vapor-liquid device is a fractionating tower 1, the top of the vapor-liquid separation tank 3 is connected to the vapor downstream pipeline, and the bottom of the vapor-liquid separation tank 3 is connected to the liquid phase reflux pipeline or the delivery pipeline through a reflux delivery pump 4, but not limited thereto.
In a preferred embodiment, further comprising: a first valve (not shown) and a first temperature sensor (not shown). Wherein the first valve is connected in series with a pipeline between the high temperature heat exchange unit 21 and the low temperature heat exchange unit 22. The first temperature sensor is disposed in the high temperature heat exchange unit 21 and connected to the first valve, the first temperature sensor detects a first temperature of the heat medium water, and when the first temperature of the heat medium water is higher than a first preset temperature threshold, the first valve is opened to enable the heat exchanged top gas to flow to the low temperature heat exchange unit 22, so that temperature control of the top gas in the high temperature heat exchange unit 21 is realized, but not limited to this.
In a preferred embodiment, further comprising: a second valve (not shown) and a second temperature sensor (not shown). Wherein the second valve is connected in series with the pipeline between the cryogenic heat exchange unit 22 and the gas-liquid separation tank 3. The second temperature sensor is disposed in the low temperature heat exchange unit 22 and connected to the second valve, the second temperature sensor detects the temperature of the top gas, and when the temperature of the top gas is lower than a second preset temperature threshold, the second valve is opened to enable the top gas after heat exchange to flow to the gas-liquid separation tank 3, thereby realizing temperature control of the top gas in the low temperature heat exchange unit 22, but not limited thereto.
In a preferred embodiment, the tower vapor-liquid device has a tower top temperature ranging from 70 ℃ to 120 ℃ and a tower bottom temperature ranging from 80 ℃ to 130 ℃, but is not limited thereto.
In a preferred embodiment, the temperature of the water flowing into the low-temperature heat exchange unit 22 is in the range of 30 ℃ to 40 ℃, and the temperature of the water returning out of the low-temperature heat exchange unit 22 is in the range of 40 ℃ to 50 ℃, but not limited thereto.
In a preferred embodiment, the temperature of the water flowing into the high-temperature heat exchange unit 21 from 50 ℃ to 80 ℃ is the temperature of the water flowing out of the high-temperature heat exchange unit 21 from 60 ℃ to 90 ℃, but the invention is not limited thereto.
According to another aspect of the present invention, the present invention also provides a total recovery method of residual heat from overhead gas, using the aforementioned total recovery system of residual heat from overhead gas, comprising the steps of:
the high-temperature heat exchange unit 21 receives the tower top gas of the tower type vapor-liquid device, receives the heat medium water of the high-temperature heat exchange unit 21 through the high-temperature working medium evaporator 11, and evaporates the first refrigerant through the heat of the heat medium water to form a first heat exchange cycle.
The first refrigerant which is received from the high-temperature working medium evaporator 11 after evaporation and gasification is condensed through the high-temperature working medium condenser 13, and the material at the bottom of the tower type vapor-liquid device is heated through a circulating pipeline, so that a second heat exchange cycle is formed.
The low-temperature heat exchange unit 22 receives the tower top gas flowing out of the high-temperature heat exchange unit 21, receives cooling water of the low-temperature heat exchange unit 22 through the medium-temperature working medium evaporator 6, and evaporates the second refrigerant through heat of the cooling water to form a third heat exchange cycle.
The second refrigerant which is received from the medium temperature working medium evaporator 6 after evaporation and gasification is condensed through the medium temperature working medium condenser 8, so as to form a fourth heat exchange cycle. And
The heat of the second refrigerant heats the heat medium water and then is conveyed to the bottom of the high-temperature heat exchange unit 21, so that a fifth heat exchange cycle is formed.
In a preferred embodiment, the five heat exchange cycles may be performed simultaneously, but are not limited thereto.
In a preferred embodiment, further comprising: and detecting the first temperature of the heat medium water in the high-temperature heat exchange unit 21 in real time, judging whether the first temperature is higher than a first preset temperature threshold value, if so, communicating the high-temperature heat exchange unit 21 with the low-temperature heat exchange unit 22, and enabling the top gas after heat exchange to flow to the low-temperature heat exchange unit 22. If not, the high-temperature heat exchange unit 21 and the low-temperature heat exchange unit 22 are cut off, so that the tower top gas can continuously exchange heat with the heat medium water, but the method is not limited to the method.
In a preferred embodiment, further comprising: and detecting a second temperature of the tower top gas in the low-temperature heat exchange unit 22 in real time, judging whether the second temperature is lower than a second preset temperature threshold value, and if yes, communicating the low-temperature heat exchange unit 22 with the gas-liquid separation tank 3. If not, the low-temperature heat exchange unit 22 and the gas-liquid separation tank 3 are cut off, so that the tower top gas can continuously exchange heat with the cooling water, but the method is not limited to the method.
The specific implementation process of the total recovery method of the residual heat of the overhead gas is as follows:
with continued reference to FIG. 1, the present invention includes: the device comprises a fractionating tower 1, a multi-flow heat exchange container 2, a gas-liquid separation tank 3, a reflux delivery pump 4, a cooling water circulating pump 5, a medium temperature working medium evaporator 6, a medium temperature working medium booster 7, a medium temperature working medium condenser 8, a medium temperature working medium throttling expander 9, a heat medium water circulating pump 10, a high temperature working medium evaporator 11, a high temperature working medium booster 12, a high temperature working medium condenser 13 and a high temperature working medium throttling expander 14. Wherein the multi-stream heat exchange vessel 2 comprises: a high temperature heat exchange unit 21 and a low temperature heat exchange unit 22. Since the present disclosure relates to a plurality of pipelines, in order to specifically describe the temperature and the shape change of the object in each pipeline, the following respectively represent different pipelines through S1 to S22 (see fig. 1): s1 is a pipeline from the top of the fractionating tower 1 to the top of the high temperature heat exchange unit 21. S2 is a pipeline from the bottom of the low-temperature heat exchange unit 22 to the gas-liquid separation tank 3. S3 is a pipeline from the gas-liquid separation tank 3 to a gas-phase downstream pipeline. S4 is a pipeline from the gas-liquid separation tank 3 to the reflux delivery pump 4. S5 is a pipeline from the reflux delivery pump 4 to the liquid phase reflux pipeline or the delivery pipeline. S6 is a pipeline from the medium-temperature working medium evaporator 6 to the cooling water circulating pump 5. S7 is a pipeline from the cooling water circulation pump 5 to the bottom of the low-temperature heat exchange unit 22. S8 is a pipeline from the top of the low-temperature heat exchange unit 22 to the medium-temperature working medium evaporator 6. S9 is a pipeline from the medium temperature working medium evaporator 6 to the medium temperature working medium booster 7. S10 is a pipeline from the medium temperature working medium booster 7 to the medium temperature working medium condenser 8. S11 is a pipeline from the medium temperature working medium condenser 8 to the medium temperature working medium throttling expander 9. S12 is a pipeline from the medium temperature working medium throttling expander 9 to the medium temperature working medium evaporator 6. S13 is a pipeline from the high-temperature working medium evaporator 11 to the heat medium water circulating pump 10. S14 is a pipeline from the heat medium water circulating pump 10 to the medium temperature working medium condenser 8. S15 is a pipeline from the medium-temperature working medium condenser 8 to the bottom of the high-temperature heat exchange unit 21. S16 is a pipeline from the top of the high-temperature heat exchange unit 21 to the high-temperature working medium evaporator 11. S17 is a pipeline from the high-temperature working medium evaporator 11 to the high-temperature working medium booster 12. S18 is a pipeline from the high-temperature working medium booster 12 to the high-temperature working medium condenser 13. S19 is a pipeline from the high-temperature working medium condenser 13 to the high-temperature working medium throttling expander 14. S20 is a pipeline from the high-temperature working medium throttling expander 14 to the high-temperature working medium evaporator 11. S21 is a pipeline from the bottom of the fractionating tower 1 to the bottom of the high-temperature working medium condenser 13. S22 is a pipeline from the top of the high-temperature working medium condenser 13 to the bottom of the fractionating tower 1.
The invention is suitable for the fractionating tower with the temperature range of 70-120 ℃ at the top of the fractionating tower; the bottom temperature of the fractionating tower is 80-130 ℃. The high-temperature tower top gas (positioned in a pipeline S1) of the fractionating tower is pumped out from the top of the fractionating tower 1, firstly enters a multi-flow heat exchange container 2, firstly passes through a high-temperature heat exchange unit 21 to carry out deep heat exchange with hot medium water, the temperature of the hot medium water rises to a set value, then enters a low-temperature heat exchange unit 22 to carry out deep heat exchange with cooling water, the temperature of the tower top gas (positioned in the pipeline S2) is reduced to the set value, then enters a gas-liquid separation tank 3 to realize gas-liquid separation, a gas phase component (positioned in the pipeline S3) enters a downstream process, and a liquid phase component (positioned in a pipeline S4) enters a reflux conveying pump 4 to carry out reflux or outward conveying after being pressurized.
The medium-temperature waste heat recovery, upgrading and utilizing process comprises the following steps:
the cooling water flowing out from the medium temperature working medium evaporator 6 with the temperature of 30-40 ℃ is pressurized to a set pressure by a cooling water circulating pump 5, enters a low temperature heat exchange unit 22 of the multi-flow heat exchange container 2, carries out deep heat exchange with the tower top gas, reduces the temperature of the tower top gas to the set value, correspondingly increases the temperature of the cooling water to the temperature of 40-50 ℃, is pumped out from a pipeline S8, enters the medium temperature working medium evaporator 6 for cooling, and circulates after the working medium of the medium temperature working medium evaporator 6 is cooled;
the medium temperature working medium (positioned in a pipeline S12) is a low-temperature low-pressure liquid phase, is heated by a medium temperature working medium evaporator 6 and exchanges heat with cooling water deeply, the medium temperature working medium is vaporized in the evaporator, enters a medium temperature working medium booster 7 to boost the working medium into a micro-overheat gas phase working medium with high temperature and high pressure, then enters a medium temperature working medium condenser 8 to cool, and the temperature of the heating medium water is increased from 50 ℃ to 80 ℃ to 55 ℃ to 85 ℃.
Meanwhile, the high-temperature waste heat recovery, upgrading and utilizing process in the invention comprises the following steps:
the heat medium water flowing out from the high-temperature working medium evaporator 11 and having the temperature of 50-80 ℃ is pressurized to a set pressure through the heat medium water circulating pump 10, enters the medium-temperature working medium condenser 8 to be heated to 55-85 ℃, enters the high-temperature heat exchange unit 21 of the multi-flow heat exchange container 2, carries out deep heat exchange with tower top gas, reduces the temperature of the tower top gas to a set value, correspondingly increases the temperature of the heat medium water to be between 60-90 ℃, is pumped out from a pipeline S16, enters the high-temperature working medium evaporator 11 to be cooled, and circulates after being cooled through the working medium of the high-temperature working medium evaporator 11;
the high-temperature working medium (positioned in a pipeline S20) is a low-temperature low-pressure liquid phase, is heated by a high-temperature working medium evaporator 11, exchanges heat with heat medium water deeply, is vaporized in the evaporator, enters a high-temperature working medium booster 12 to boost the working medium into a micro-overheat gas-phase working medium with high temperature and high pressure, enters a high-temperature working medium condenser 13 to cool, and reboiles and heats the process material at the top of the fractionating tower 1 to a set value.
Wherein, the cooling water and the heating medium water can adopt desalted water or deoxidized water, and do not adopt circulating water. Cooling water operating temperature: the upper water temperature is 30-40 ℃ and the return water temperature is 40-50 ℃; heat medium water operating temperature: the upper water temperature is 50 ℃ to 80 ℃ and the return water temperature is 60 ℃ to 90 ℃.
In this example, 30 ten thousand tons/year of CO is produced by the chemical solvent method 2 Capturing project CO 2 Compared with the zero recovery and partial recovery technology of the waste heat of the overhead gas, the energy consumption of the regeneration tower can be effectively reduced after the full recovery system and the full recovery method of the waste heat of the overhead gas are used.
The relevant case parameters are as follows:
after the implementation of the case, compared with zero recovery, the heat recovery rate of the technology is 100 percent, and compared with partial recovery, the heat recovery rate of the technology is 31.7 percent higher; the steam reduction rate of the full recovery is 64.6 percent, which is 22.9 percent higher than that of the partial recovery; the energy saving rate of the full recovery is 19.7%, which is 3.6% higher than that of the partial recovery, and the energy saving benefit is remarkable.
In summary, the total recovery system and the total recovery method for the waste heat of the overhead gas can fully recover the waste heat of the overhead gas, so that the system is more stable in working state and higher in heat utilization efficiency, and meanwhile, the heat extraction cost is reduced.
The invention has been described with respect to the above-described embodiments, however, the above-described embodiments are merely examples of practicing the invention. It should be noted that the disclosed embodiments do not limit the scope of the invention. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.
Claims (12)
1. An overhead gas waste heat total recovery system, comprising:
the multi-flow heat exchange container (2) comprises a high-temperature heat exchange unit (21) positioned at the upper part and a low-temperature heat exchange unit (22) positioned at the lower part, wherein the high-temperature heat exchange unit (21) receives tower top gas from a tower type vapor-liquid device and is communicated with the low-temperature heat exchange unit (22) through an internal pipeline with a valve;
a gas-liquid separation tank (3) which is communicated with the lower part of the low-temperature heat exchange unit (22) and performs gas-liquid separation;
the high-temperature working medium evaporator (11) is communicated with the top of the high-temperature heat exchange unit (21) through a pipeline to receive heat medium water, and the first refrigerant is evaporated through the heat of the heat medium water;
the medium-temperature working medium condenser (8) is connected with the bottom of the high-temperature working medium evaporator (11) through a pipeline, and is used for heating the heat medium water and then conveying the heat medium water to the bottom of the high-temperature heat exchange unit (21) to exchange heat with the tower top gas in the high-temperature heat exchange unit (21);
the high-temperature working medium condenser (13) forms high-temperature heat exchange circulation with the high-temperature working medium evaporator (11) through a pipeline with the first refrigerant, the first refrigerant after evaporation and gasification received from the high-temperature working medium evaporator (11) is condensed, and the material at the bottom of the tower type vapor-liquid device is heated through a circulation pipeline;
the medium temperature working medium evaporator (6) forms medium temperature heat exchange circulation with the medium temperature working medium condenser (8) through a pipeline with a second refrigerant, the heat of the medium temperature working medium is used for heating the heat medium water, the medium temperature working medium evaporator (6) is communicated with the top of the low temperature heat exchange unit (22) through a pipeline to receive cooling water, the second refrigerant is evaporated through the heat of the cooling water, the cooled cooling water is conveyed to the bottom of the low temperature heat exchange unit (22), heat exchange is carried out again with the tower top gas in the low temperature heat exchange unit (22), and the temperature of the heat medium water flowing out of the high temperature heat exchange unit (21) is higher than the temperature of the cooling water flowing out of the low temperature heat exchange unit (22);
a heat medium water circulating pump (10) which is communicated with the high-temperature working medium evaporator (11) and the medium-temperature working medium condenser (8) and is used for pressurizing the heat medium water flowing out of the high-temperature working medium evaporator (11) and then conveying the heat medium water to the medium-temperature working medium condenser (8);
a high-temperature working medium booster (12) which is communicated with the high-temperature working medium evaporator (11) and the high-temperature working medium condenser (13) and is used for boosting the high-temperature working medium flowing out of the high-temperature working medium evaporator (11) into a high-temperature high-pressure micro-overheat gas-phase working medium and then conveying the micro-overheat gas-phase working medium to the high-temperature working medium condenser (13);
a high-temperature working medium throttling expander (14) connected in series in a pipeline from the high-temperature working medium condenser (13) to the high-temperature working medium evaporator (11) so that the first refrigerant flowing into the high-temperature working medium evaporator (11) is low-temperature low-pressure liquid;
a cooling water circulating pump (5) which is communicated with the medium temperature working medium evaporator (6) and the low temperature heat exchange unit (22) and is used for pressurizing cooling water flowing out of the medium temperature working medium evaporator (6) and then delivering the pressurized cooling water to the low temperature heat exchange unit (22);
the medium temperature working medium booster (7) is communicated with the medium temperature working medium evaporator (6) and the medium temperature working medium condenser (8), and the medium temperature working medium flowing out of the medium temperature working medium evaporator (6) is boosted into a micro-overheat gas phase working medium with high temperature and high pressure and then is conveyed to the medium temperature working medium condenser (8); and
and a medium temperature working medium throttling expander (9) connected in series with a pipeline of the medium temperature working medium condenser (8) flowing to the medium temperature working medium evaporator (6) so that the second refrigerant flowing into the medium temperature working medium evaporator (6) is a low-temperature low-pressure liquid phase.
2. The total overhead gas waste heat recovery system of claim 1, further comprising: the temperature range of the high-temperature high-pressure micro-overheat gas phase working medium is 100 ℃ to 135 ℃ and the pressure range is 1.5Mpag to 3.0Mpag.
3. The total overhead gas waste heat recovery system of claim 1, further comprising: the low temperature low pressure liquid phase has a temperature in the range of 50 ℃ to 75 ℃ and a pressure in the range of 0.35Mpa to 0.7 Mpa.
4. The total overhead gas waste heat recovery system of claim 1, further comprising: the temperature range of the high-temperature high-pressure micro-overheat gas phase working medium is 60-90 ℃, and the pressure range is 2.5-5.2 Mpag.
5. The total overhead gas waste heat recovery system of claim 1, further comprising: the low temperature low pressure liquid phase has a temperature in the range of 20 ℃ to 35 ℃ and a pressure in the range of 0.8Mpa to 1.5 Mpa.
6. The total recovery system for residual heat from overhead gas according to claim 1, wherein said tower type vapor-liquid apparatus is a fractionating tower (1), the top of said vapor-liquid separating tank (3) is connected to a downstream gas-phase pipeline, and the bottom of said vapor-liquid separating tank (3) is connected to a liquid-phase reflux pipeline or an outgoing pipeline via a reflux transfer pump (4).
7. The total overhead gas waste heat recovery system of claim 1, further comprising:
the first valve is connected in series with a pipeline between the high-temperature heat exchange unit (21) and the low-temperature heat exchange unit (22); and
the first temperature sensor is arranged on the high-temperature heat exchange unit (21) and connected with the first valve, detects the first temperature of the heat medium water, and opens the first valve when the first temperature of the heat medium water is higher than a first preset temperature threshold value, so that the top gas after heat exchange flows to the low-temperature heat exchange unit (22).
8. The total overhead gas waste heat recovery system of claim 1, further comprising:
the second valve is connected in series with a pipeline between the low-temperature heat exchange unit (22) and the gas-liquid separation tank (3); and
the second temperature sensor is arranged in the low-temperature heat exchange unit (22) and is connected with the second valve, the second temperature sensor detects the temperature of the tower top gas, and when the temperature of the tower top gas is lower than a second preset temperature threshold value, the second valve is opened, so that the tower top gas subjected to heat exchange again flows to the gas-liquid separation tank (3).
9. The total recovery system of overhead gas waste heat of claim 1, wherein the tower vapor-liquid device has a tower top temperature in the range of 70 ℃ to 120 ℃ and a tower bottom temperature in the range of 80 ℃ to 130 ℃;
the temperature of the water flowing into the low-temperature heat exchange unit (22) is 30-40 ℃, and the temperature of the backwater flowing out of the low-temperature heat exchange unit (22) is 40-50 ℃;
the water supply temperature of the heating medium flowing into the high-temperature heat exchange unit (21) ranges from 50 ℃ to 80 ℃, and the water return temperature flowing out of the high-temperature heat exchange unit (21) ranges from 60 ℃ to 90 ℃.
10. The total recovery method of the waste heat of the overhead gas, which adopts the total recovery system of the waste heat of the overhead gas as claimed in claim 1, is characterized by comprising the following steps:
the high-temperature heat exchange unit (21) receives tower top gas of the tower type vapor-liquid device, receives heat medium water of the high-temperature heat exchange unit (21) through the high-temperature working medium evaporator (11), and evaporates a first refrigerant through heat of the heat medium water to form a first heat exchange cycle;
the first refrigerant which is received from the high-temperature working medium evaporator (11) through the high-temperature working medium condenser (13) after evaporation and gasification is condensed, and materials at the bottom of the tower type vapor-liquid device are heated through a circulating pipeline to form a second heat exchange cycle;
the low-temperature heat exchange unit (22) receives the tower top gas flowing out of the high-temperature heat exchange unit (21), receives cooling water of the low-temperature heat exchange unit (22) through the medium-temperature working medium evaporator (6), and evaporates a second refrigerant through heat of the cooling water to form a third heat exchange cycle;
the second refrigerant which is received from the medium temperature working medium evaporator (6) after evaporation and gasification is condensed through the medium temperature working medium condenser (8) to form a fourth heat exchange cycle; and
and heating the heat medium water by the heat of the second refrigerant, and then conveying the heat medium water to the bottom of the high-temperature heat exchange unit (21) to form a fifth heat exchange cycle.
11. The total recovery method of overhead gas waste heat of claim 10, further comprising: detecting a first temperature of heat medium water in the high-temperature heat exchange unit (21) in real time, judging whether the first temperature is higher than a first preset temperature threshold value, if yes, communicating the high-temperature heat exchange unit (21) with the low-temperature heat exchange unit (22), and enabling the tower top gas after heat exchange to flow to the low-temperature heat exchange unit (22); if not, the high-temperature heat exchange unit (21) and the low-temperature heat exchange unit (22) are cut off, so that the tower top gas continuously exchanges heat with the heat medium water.
12. The total recovery method of overhead gas waste heat of claim 10, further comprising: detecting a second temperature of the tower top gas in the low-temperature heat exchange unit (22) in real time, judging whether the second temperature is lower than a second preset temperature threshold value, and if yes, communicating the low-temperature heat exchange unit (22) with the gas-liquid separation tank (3); if not, the low-temperature heat exchange unit (22) and the gas-liquid separation tank (3) are cut off, so that the tower top gas continuously exchanges heat with the cooling water.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102937039A (en) * | 2011-08-15 | 2013-02-20 | 北京天成山泉电子科技有限公司 | Liquefied natural gas (LNG) cold energy multistage recycling system suitable for ship and using method thereof |
| CN204267120U (en) * | 2014-11-25 | 2015-04-15 | 国核柏斯顿新能源科技(北京)有限公司 | Adopt the low-temperature waste heat power generation equipment of frequency conversion automatic control technology |
| CN107621096A (en) * | 2017-09-15 | 2018-01-23 | 中国科学院工程热物理研究所 | A kind of chemical heat pump system for the recovery of low temperature exhaust heat depth |
| CN207730035U (en) * | 2017-12-06 | 2018-08-14 | 中国科学技术大学 | Sintering with Organic Rankine Cycle cools down power generation system using waste heat |
| CN109916108A (en) * | 2019-01-07 | 2019-06-21 | 燕山大学 | A kind of hot water step heating preparation system for realizing the recycling of freezer condensation heat depth |
| CN211011566U (en) * | 2019-08-29 | 2020-07-14 | 山东昌邑石化有限公司 | Refinery low-temperature heat recovery comprehensive utilization system |
| CN211041462U (en) * | 2019-10-29 | 2020-07-17 | 中机国能炼化工程有限公司 | Waste heat recovery trans-critical CO of gas cooler2Refrigeration system |
-
2023
- 2023-12-22 CN CN202311777838.7A patent/CN117469839B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102937039A (en) * | 2011-08-15 | 2013-02-20 | 北京天成山泉电子科技有限公司 | Liquefied natural gas (LNG) cold energy multistage recycling system suitable for ship and using method thereof |
| CN204267120U (en) * | 2014-11-25 | 2015-04-15 | 国核柏斯顿新能源科技(北京)有限公司 | Adopt the low-temperature waste heat power generation equipment of frequency conversion automatic control technology |
| CN107621096A (en) * | 2017-09-15 | 2018-01-23 | 中国科学院工程热物理研究所 | A kind of chemical heat pump system for the recovery of low temperature exhaust heat depth |
| CN207730035U (en) * | 2017-12-06 | 2018-08-14 | 中国科学技术大学 | Sintering with Organic Rankine Cycle cools down power generation system using waste heat |
| CN109916108A (en) * | 2019-01-07 | 2019-06-21 | 燕山大学 | A kind of hot water step heating preparation system for realizing the recycling of freezer condensation heat depth |
| CN211011566U (en) * | 2019-08-29 | 2020-07-14 | 山东昌邑石化有限公司 | Refinery low-temperature heat recovery comprehensive utilization system |
| CN211041462U (en) * | 2019-10-29 | 2020-07-17 | 中机国能炼化工程有限公司 | Waste heat recovery trans-critical CO of gas cooler2Refrigeration system |
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