CN111023076A - Full-open type absorption heat pump for flue gas waste heat full-heat gradient depth recovery - Google Patents
Full-open type absorption heat pump for flue gas waste heat full-heat gradient depth recovery Download PDFInfo
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- CN111023076A CN111023076A CN201911219614.8A CN201911219614A CN111023076A CN 111023076 A CN111023076 A CN 111023076A CN 201911219614 A CN201911219614 A CN 201911219614A CN 111023076 A CN111023076 A CN 111023076A
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D11/00—Central heating systems using heat accumulated in storage masses
- F24D11/02—Central heating systems using heat accumulated in storage masses using heat pumps
- F24D11/0214—Central heating systems using heat accumulated in storage masses using heat pumps water heating system
- F24D11/0235—Central heating systems using heat accumulated in storage masses using heat pumps water heating system with recuperation of waste energy
- F24D11/0242—Central heating systems using heat accumulated in storage masses using heat pumps water heating system with recuperation of waste energy contained in exhausted air
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22D—PREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER FOR STEAM GENERATION; FEED-WATER SUPPLY FOR STEAM GENERATION; CONTROLLING WATER LEVEL FOR STEAM GENERATION; AUXILIARY DEVICES FOR PROMOTING WATER CIRCULATION WITHIN STEAM BOILERS
- F22D1/00—Feed-water heaters, i.e. economisers or like preheaters
- F22D1/16—Feed-water heaters, i.e. economisers or like preheaters with water tubes arranged otherwise than in the boiler furnace, fire tubes, or flue ways
- F22D1/18—Feed-water heaters, i.e. economisers or like preheaters with water tubes arranged otherwise than in the boiler furnace, fire tubes, or flue ways and heated indirectly
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES
- F23J15/00—Arrangements of devices for treating smoke or fumes
- F23J15/02—Arrangements of devices for treating smoke or fumes of purifiers, e.g. for removing noxious material
- F23J15/022—Arrangements of devices for treating smoke or fumes of purifiers, e.g. for removing noxious material for removing solid particulate material from the gasflow
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES
- F23J15/00—Arrangements of devices for treating smoke or fumes
- F23J15/06—Arrangements of devices for treating smoke or fumes of coolers
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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
- F25B30/00—Heat pumps
- F25B30/04—Heat pumps of the sorption type
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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
- F25B30/00—Heat pumps
- F25B30/06—Heat pumps characterised by the source of low potential heat
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
- Y02B30/52—Heat recovery pumps, i.e. heat pump based systems or units able to transfer the thermal energy from one area of the premises or part of the facilities to a different one, improving the overall efficiency
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E20/00—Combustion technologies with mitigation potential
- Y02E20/30—Technologies for a more efficient combustion or heat usage
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Treating Waste Gases (AREA)
Abstract
The invention discloses a full-open type absorption heat pump for full-heat gradient depth recovery of flue gas waste heat, which comprises a flue gas loop, a solution loop, a circulating water loop and a heat supply network water loop, wherein the solution loop realizes full-heat depth recovery of low-temperature exhaust smoke of a boiler, a small amount of medium-temperature flue gas in front of an air preheater is used for regenerating the solution after heat absorption and moisture absorption, the flue gas carrying a large amount of sensible heat and latent heat is subjected to full-heat depth recovery through the circulating water loop, and all heat generated in the full-heat recovery process is supplied to the heat supply network backwater; compared with the traditional absorption heat pump in waste heat utilization, the vacuum environment is not needed, so that the manufacturing cost and the operation and maintenance difficulty are greatly reduced. The direct contact packed tower is used as a device for exchanging heat between solution/water and flue gas, so that the heat transfer capacity is improved, and the corrosion problem of the dividing wall type heat exchanger in waste heat utilization is thoroughly solved.
Description
Technical Field
The invention belongs to the field of waste heat recovery and utilization, and relates to a full-open type absorption heat pump for full-heat gradient depth recovery of flue gas waste heat.
Background
All contain a large amount of vapor in coal-fired gas electric field boiler's the exhaust fume, when the chimney discharges fume and the air contact of outdoor environment, the vapor in the flue gas can meet the condensation knot at the chimney exit, forms "white cigarette" phenomenon, causes visual pollution, and this phenomenon still is unfavorable for the flue gas lifting diffusion, can cause the corruption to equipment and building around the chimney, still can influence the ecological environment in every side. A large amount of sensible heat and latent heat contained in the flue gas is discharged to the outside, resulting in waste of energy.
At present, the following problems mainly exist in the methods of flue gas waste heat recovery and white elimination which are mainly adopted: (1) the dividing wall type waste heat recovery heat exchanger has the problem of low-temperature corrosion due to the fact that flue gas contains sulfur and other components; (2) the closed absorption heat pump has the defects that a cold source is difficult to find, and the equipment is expensive and difficult to maintain due to the fact that the system needs to maintain vacuum; (3) the system for deeply recovering the waste heat by using the solution has no proper method for regenerating the solution, still can discharge water vapor outdoors by using outdoor air as a regeneration carrier, and still has the problem of low energy utilization rate when a high-grade heat source such as fuel combustion heat is selected as a regeneration heat source.
In the prior art, some absorption heat pumps are used for recovering the waste heat of the flue gas, and a flue gas-water direct contact type heat exchanger is used for replacing a dividing wall type heat exchanger to recover the waste heat of the flue gas, but the absorption heat pumps are difficult to manufacture and high in cost, the flue gas is in a saturated state, and a tail flue is easy to condense and corrode. Still some utilize solution to retrieve the waste heat of discharging fume based on solution absorption endless flue gas waste heat, have reduced the dew point temperature of discharging fume, but this system directly utilizes the high temperature flue gas of fuel burning to drive solution regeneration, and primary energy utilization is rateed lowly. Some solutions and cooling water are used for absorbing the waste heat in the flue gas, a dividing wall type heat exchanger is still adopted in the flue gas waste heat recovery, the corrosion is easily caused, the system still uses outdoor air as a carrier for solution regeneration, although the moisture content of the flue gas is reduced, the exhaust of a regeneration device is close to saturation, and the smoke plume phenomenon can be caused.
Therefore, designing a system for flue gas waste heat full-thermal gradient deep recovery and upgrading is a problem urgently needed to be solved by the technical personnel in the field.
Disclosure of Invention
The purpose of the invention is as follows: in order to solve the defects of the prior art, the invention provides a full-open type absorption heat pump for full-heat gradient deep recovery of flue gas waste heat, which utilizes solution to perform full-heat deep recovery on boiler exhaust smoke, utilizes flue gas in front of an air preheater to upgrade the recovered heat and supplies the upgraded heat to a heat supply network, and realizes energy conservation and emission reduction. The system can also eliminate the wet smoke plume phenomenon (smoke whitening), and the direct contact gas-liquid heat exchanger also solves the corrosion problem of the traditional dividing wall type heat exchanger.
The technical scheme is as follows: in order to realize the purpose, the invention adopts the following technical scheme:
a full-open type absorption heat pump for flue gas waste heat full-heat gradient depth recovery comprises a flue gas loop, a solution loop, a circulating water loop and a heat supply network water loop. The full-heat deep recovery is realized on the low-temperature smoke exhaust of the boiler by using a solution loop, the solution after absorbing heat and moisture is regenerated by using a small amount of medium-temperature smoke in front of an air preheater, the smoke carrying a large amount of sensible heat and latent heat is subjected to the full-heat deep recovery through a circulating water loop, and all heat generated in the full-heat recovery process is supplied to a heat supply network for returning water. Compared with the traditional absorption heat pump in waste heat utilization, the fully-open system greatly reduces the manufacturing cost and the operation and maintenance difficulty because the system does not need a vacuum environment. The direct contact packed tower is used as a device for exchanging heat between solution/water and flue gas, so that the heat transfer capacity is improved, and the corrosion problem of the dividing wall type heat exchanger in waste heat utilization is thoroughly solved.
The method specifically comprises the following steps:
the utility model provides a flue gas waste heat total heat step degree of depth recovery's full open absorption heat pump, this system includes the flue gas return circuit, the solution return circuit, circulating water return circuit and heat supply network water return circuit, wherein, the flue gas return circuit is used for carrying economizer export flue gas, utilize the solution return circuit to realize discharging fume to boiler low temperature and carry out the total heat degree of depth recovery, utilize a small amount of middle temperature flue gas to regenerate to the solution after the heat absorption moisture absorption, the flue gas that carries a large amount of sensible heat and latent heat carries out the total heat degree of depth recovery through the circulating water return circuit, the heat that produces in the total heat recovery process all supplies the heat supply network return water in the.
Optionally, the flue gas loop comprises a denitration device, an air preheater, an electric precipitator, a desulfurization device, a smoke exhaust chimney, a first gas-liquid direct contact heat exchanger, a second gas-liquid direct contact heat exchanger, a third gas-liquid direct contact heat exchanger, a first fan, a second fan, a first electromagnetic valve, a fifth electromagnetic valve, a sixth electromagnetic valve, a seventh electromagnetic valve and related pipelines, wherein flue gas at an outlet of the economizer is input into an input end of the denitration device, an output end of the denitration device is connected with a first input end of the air preheater, a first output end of the air preheater is connected with an input end of the electric precipitator, an output end of the electric precipitator is connected with an input end of the desulfurization device, and an output end of the desulfurization device is connected with an input end of the smoke exhaust chimney through the seventh; in addition, the denitration device is connected with a first input end of the first gas-liquid direct contact heat exchanger through a first electromagnetic valve, a first output end of the first gas-liquid direct contact heat exchanger is connected with a first input end of the second gas-liquid direct contact heat exchanger, a first output end of the second gas-liquid direct contact heat exchanger is connected with a first input end of a third gas-liquid direct contact heat exchanger, and a first output end of the third gas-liquid direct contact heat exchanger is connected with an input end of the smoke exhaust chimney through a sixth electromagnetic valve; the output end of the desulfurization device is connected with the second input end of the third gas-liquid direct contact heat exchanger through a fifth electromagnetic valve; the first fan is connected with the second input end of the air preheater, and the second output end of the air preheater outputs hearth hot air; and the third fan is connected with the third input end of the air preheater, and the third output end of the air preheater outputs hot air of the coal mill.
Optionally, the first gas-liquid direct contact heat exchanger, the second gas-liquid direct contact heat exchanger and the third gas-liquid direct contact heat exchanger are all direct contact packed towers, the packed towers are in a counter-flow or cross-flow mode, and the packing is bulk or regular high-temperature-resistant corrosion-resistant packing.
Optionally, the solution loop includes a first dividing wall type liquid-liquid heat exchanger, a third dividing wall type liquid-liquid heat exchanger, a first pump, a third electromagnetic valve, an eighth electromagnetic valve and related pipelines, wherein a second output end of a first gas-liquid direct contact heat exchanger in the flue gas loop is connected with a first input end of the first dividing wall type liquid-liquid heat exchanger through the first pump, a first output end of the first dividing wall type liquid-liquid heat exchanger is connected with a third input end of the third gas-liquid direct contact heat exchanger, a second output end of the third gas-liquid direct contact heat exchanger is connected with an input end of the third pump, one path of an output end of the third pump is connected with a second input end of the first dividing wall type liquid-liquid heat exchanger through the eighth electromagnetic valve, the other path is connected with a first input end of the third dividing wall type liquid-liquid heat exchanger through the third electromagnetic valve, a first output end of the third dividing wall type liquid-liquid heat exchanger is connected with a second input end of the first, and the second output end of the first dividing wall type liquid-liquid heat exchanger is connected with the second input end of the first gas-liquid direct contact heat exchanger in the flue gas loop.
Optionally, the circulating working medium in the solution loop is a solution with a low water vapor partial pressure, such as LiCl, LiBr or CaCl2 solution, or an alcohol organic solution.
Optionally, the circulating water loop includes a second partition-type liquid-liquid heat exchanger, a second pump, a condensed water drainage device and related pipelines, wherein a second output end of a second gas-liquid direct contact heat exchanger in the flue gas loop is connected with a first input end of the second partition-type liquid-liquid heat exchanger through the second pump, and a first output end of the second partition-type liquid-liquid heat exchanger is connected with a second input port of the second gas-liquid direct contact heat exchanger in the flue gas loop; in addition, the condensed water discharging device is arranged at the lower part of the second gas-liquid direct contact heat exchanger in the flue gas loop and used for discharging the condensed water from the flue gas.
Optionally, the heat supply network water loop comprises a second electromagnetic valve, a fourth electromagnetic valve and a related pipeline, the heat supply network return water is respectively connected with a second input end of a second dividing wall type liquid-liquid heat exchanger in the circulating water loop and a second input end of a third dividing wall type liquid-liquid heat exchanger in the solution loop through the second electromagnetic valve and the fourth electromagnetic valve, and a second output end of the second dividing wall type liquid-liquid heat exchanger in the circulating water loop and a second output end of the third dividing wall type liquid-liquid heat exchanger in the solution loop are both connected with the heat supply network water supply.
Has the advantages that: compared with the prior art, the invention has the following advantages:
(1) the invention realizes the full-heat deep recovery of the boiler exhaust smoke by using the solution/water, and thoroughly solves the problem of wet smoke and rain of the boiler exhaust smoke.
(2) The invention uses a small amount of medium-temperature flue gas in front of the air device to upgrade the total heat of the discharged smoke and supplies heat to the heat supply network, thereby realizing the gradient utilization of the flue gas waste heat.
(3) The invention adopts the direct contact packed tower as a device for exchanging heat between solution/water and flue gas, improves the heat and mass transfer capacity and thoroughly solves the corrosion problem of the dividing wall type heat exchanger in waste heat utilization.
(4) Compared with the traditional absorption heat pump in waste heat utilization, the fully-open absorption heat pump has the advantages that the manufacturing cost and the operation and maintenance difficulty are greatly reduced.
Drawings
FIG. 1 is a schematic diagram of the system of the present invention;
in the figure: the system comprises a denitration device 1, an air preheater 2, an electric dust remover 3, a desulfurization device 4, a smoke exhaust chimney 5, a first gas-liquid direct contact heat exchanger 6, a second gas-liquid direct contact heat exchanger 7, a third gas-liquid direct contact heat exchanger 8, a first dividing wall type liquid-liquid heat exchanger 9, a second dividing wall type liquid-liquid heat exchanger 10, a third dividing wall type liquid-liquid heat exchanger 11, a first fan 12, a second fan 13, a first pump 14, a second pump 15, a third pump 16, a first electromagnetic valve 17, a second electromagnetic valve 18, a third electromagnetic valve 19, a fourth electromagnetic valve 20, a fifth electromagnetic valve 21, a sixth electromagnetic valve 22, a seventh electromagnetic valve 23, an eighth electromagnetic valve 24 and a condensed water drainage device 25.
Detailed Description
The technical solution of the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.
As shown in fig. 1, the fully-open absorption heat pump for flue gas waste heat total heat step depth recovery of the present invention comprises a flue gas loop, a solution loop, a circulating water loop and a heat supply network water loop. The low-temperature exhaust smoke of the boiler is subjected to full-heat deep recovery by using a solution loop, a small amount of medium-temperature flue gas in front of the air preheater is used for regenerating the solution after heat absorption and moisture absorption, the flue gas carrying a large amount of sensible heat and latent heat is subjected to full-heat deep recovery by using a circulating water loop, and all heat generated in the full-heat recovery process is supplied to heat supply network return water in a heat supply network water loop.
Wherein the flue gas return circuit includes denitrification facility 1, air preheater 2, electrostatic precipitator 3, desulphurization unit 4, chimney 5, first gas-liquid direct contact heat exchanger 6, second gas-liquid direct contact heat exchanger 7, third gas-liquid direct contact heat exchanger 8, first fan 12, second fan 13, first solenoid valve 17, fifth solenoid valve 21, sixth solenoid valve 22, seventh solenoid valve 23 and relevant pipeline. The denitration device 1, the air preheater 2, the electric dust remover 3, the desulfurization device 4 and the smoke exhaust chimney 5 are sequentially connected in series, namely, flue gas at the outlet of the coal economizer is input into the input end of the denitration device 1, the output end of the denitration device 1 is connected with the first input end of the air preheater 2, the first output end of the air preheater is connected with the input end of the electric dust remover, the output end of the electric dust remover is connected with the input end of the desulfurization device, and the output end of the desulfurization device is connected with the input end of the smoke exhaust chimney 5 through a seventh electromagnetic valve 23; in addition, the denitration device 1 is connected with the first gas-liquid direct contact heat exchanger 6 through the first electromagnetic valve 17, and then is sequentially connected with the second gas-liquid direct contact heat exchanger 7 and the third gas-liquid direct contact heat exchanger 8 in series, namely, the denitration device 1 is connected with the first input end of the first gas-liquid direct contact heat exchanger 6 through the first electromagnetic valve 17, the first output end of the first gas-liquid direct contact heat exchanger 6 is connected with the first input end of the second gas-liquid direct contact heat exchanger 7, and the first output end of the second gas-liquid direct contact heat exchanger 7 is connected with the first input end of the third gas-liquid direct contact heat exchanger 8; the first output end of the third gas-liquid direct contact heat exchanger 8 is connected with the input end of the smoke exhaust chimney 5 through a sixth electromagnetic valve 22, and the output end of the desulphurization device 4 is connected with the second input end of the third gas-liquid direct contact heat exchanger 8 through a fifth electromagnetic valve 21; the first fan 12 is connected with a second input end of the air preheater, and a second output end of the air preheater outputs hearth hot air; and a third fan 13 is connected with a third input end of the air preheater, and a third output end of the air preheater outputs hot air of the coal mill.
The first gas-liquid direct contact heat exchanger, the second gas-liquid direct contact heat exchanger and the third gas-liquid direct contact heat exchanger are direct contact packed towers, the packed towers can be in a counter flow or cross flow mode, the packing is bulk or regular high-temperature-resistant and corrosion-resistant packing, the circulating working medium in the solution loop is a solution with low water vapor partial pressure, and can be salt solutions such as LiCl, LiBr, CaCl2 and the like, and can also be an alcohol organic solution.
The flue gas taken from the front of the air preheater through the first electromagnetic valve is medium-temperature flue gas (the temperature is about 350 ℃), the medium-temperature flue gas is used as a heat source to regenerate the solution of the first gas-liquid direct contact heat exchanger, the flue gas taken from the front of the smoke exhaust chimney through the fifth electromagnetic valve is low-temperature high-humidity flue gas (the temperature is about 60 ℃, the moisture content is about 80g/kg, and is specifically determined by the properties of boiler fuel and the system working condition), and the flue gas is subjected to total heat deep recovery by the solution in the third gas-liquid direct contact heat exchanger.
The solution loop comprises a first dividing wall type liquid-liquid heat exchanger 9, a third dividing wall type liquid-liquid heat exchanger 11, a first pump 14, a third pump 16, a third electromagnetic valve 19, an eighth electromagnetic valve 24 and related pipelines, wherein a second output end (solution outlet) of a first gas-liquid direct contact heat exchanger 6 in the flue gas loop is connected with a first input end of the first dividing wall type liquid-liquid heat exchanger 9 through the first pump 14, a first output end of the first dividing wall type liquid-liquid heat exchanger 9 is connected with a third input end (solution inlet) of a third gas-liquid direct contact heat exchanger 8, a second output end (solution outlet) of the third gas-liquid direct contact heat exchanger 8 is connected with an input end of the third pump 16, an output end of the third pump 16 and the middle of the first dividing wall type liquid-liquid heat exchanger 9 are provided with two branches, one branch passes through the eighth electromagnetic valve 24, the other branch passes through the third dividing wall type electromagnetic valve 19 and the third dividing wall type liquid-liquid, that is, one path of the output end of the third pump 16 is connected with the second input end of the first dividing wall type liquid-liquid heat exchanger 9 through the eighth electromagnetic valve 24, the other path is connected with the first input end of the third dividing wall type liquid-liquid heat exchanger 11 through the third electromagnetic valve 19, the first output end of the third dividing wall type liquid-liquid heat exchanger 11 is connected with the second input end of the first dividing wall type liquid-liquid heat exchanger 9, and the second output end of the first dividing wall type liquid-liquid heat exchanger 9 is connected with the second input end of the first gas-liquid direct contact heat exchanger 6 in the flue gas loop.
The circulating water loop comprises a second partition-type liquid-liquid heat exchanger 10, a second pump 15, a condensed water drainage device 25 and related pipelines, wherein a second gas-liquid direct contact heat exchanger 7, the second pump 15 and the second partition-type liquid-liquid heat exchanger 10 in the flue gas loop are sequentially connected in series, namely a second output end of the second gas-liquid direct contact heat exchanger 7 is connected with a first input end of the second partition-type liquid-liquid heat exchanger 10 through the second pump 15, and a first output end of the second partition-type liquid-liquid heat exchanger 10 is connected with a second input port of the second gas-liquid direct contact heat exchanger 7 in the flue gas loop; in addition, a condensed water drainage device 25 is provided in the lower portion of the second gas-liquid direct contact heat exchanger 7 in the flue gas circuit for discharging the condensed water from the flue gas.
The circulating working medium in the second gas-liquid direct contact heat exchanger is water, the total heat in the flue gas is recovered by using the water, and the moisture absorbed by the whole system from the flue gas is finally discharged from the system through the condensed water discharging device in the form of condensed water, so that the latent heat waste and the environmental pollution caused by discharging the moisture to the environment from a smoke discharging chimney or a solution regenerating device in the form of water vapor are avoided.
The heat recovered in the second gas-liquid direct contact heat exchanger and the third gas-liquid direct contact heat exchanger is supplied to a heat supply network through the first dividing wall type liquid-liquid heat exchanger and the second dividing wall type liquid-liquid heat exchanger respectively, and the concentrated solution at the outlet of the first gas-liquid direct contact heat exchanger and the dilute solution at the outlet of the third gas-liquid direct contact heat exchanger exchange heat through the first dividing wall type liquid-liquid heat exchanger to enhance the total heat recovery capability.
The heat supply network water loop comprises a second electromagnetic valve 18, a fourth electromagnetic valve 20 and related pipelines, a second input end of a second partition-type liquid-liquid heat exchanger 10 in the circulating water loop is connected with the second electromagnetic valve 18 in series, a second input end of a third partition-type liquid-liquid heat exchanger 11 in the solution loop is connected with the fourth electromagnetic valve 20 in series, and the two loops are respectively connected in parallel in a water supply and return loop of the heat supply network; namely, the return water of the heat supply network is respectively connected with the second input end of the second dividing wall type liquid-liquid heat exchanger 10 in the circulating water loop and the second input end of the third dividing wall type liquid-liquid heat exchanger 11 in the solution loop through the second electromagnetic valve 18 and the fourth electromagnetic valve 20, and the second output end of the second dividing wall type liquid-liquid heat exchanger 10 in the circulating water loop and the second output end of the third dividing wall type liquid-liquid heat exchanger 11 in the solution loop are both connected with the water supply of the heat supply network.
When the system does not enter a flue gas waste heat recovery and white removal mode, the seventh electromagnetic valve 23 is fully opened, and the first electromagnetic valve 17, the second electromagnetic valve 18, the third electromagnetic valve 19, the fourth electromagnetic valve 20, the fifth electromagnetic valve 21, the sixth electromagnetic valve 22 and the eighth electromagnetic valve 24 are fully closed. Flue gas (about 370 ℃) from an outlet of the economizer enters the denitration device 1 for flue gas denitration treatment, and medium-temperature flue gas (about 350 ℃) from an outlet of the denitration device 1 enters the air preheater 2 for preheating air from the first fan 12 and the second fan 13 and respectively sending the air to the boiler and the coal mill. The flue gas (about 135 ℃) output by the first output end of the air preheater 2 enters the electric dust remover 3 and then enters the desulphurization device 4 for flue gas desulphurization treatment, and the low-temperature high-humidity flue gas (about 60 ℃, about 80g/kg and close to saturation) at the outlet of the desulphurization device 4 is discharged into the environment through the seventh electromagnetic valve 23 and the smoke exhaust chimney 5 in sequence. Because the temperature of the environment at the outlet of the smoke exhaust chimney 5 is far lower than the temperature of the outlet smoke, the smoke meets condensation to form wet smoke plume, visual pollution is caused, smoke lifting is influenced, and a large amount of sensible heat and latent heat of the smoke are wasted.
When the system enters a flue gas waste heat recovery and white removal mode, the seventh electromagnetic valve 23 is closed, the second electromagnetic valve 18, the fourth electromagnetic valve 20, the fifth electromagnetic valve 21 and the sixth electromagnetic valve 22 are fully opened, the first electromagnetic valve 17, the third electromagnetic valve 19 and the eighth electromagnetic valve 24 are opened, and the opening degrees are determined by the operation condition. The low-temperature high-humidity flue gas (about 60 ℃, about 80g/kg and close to saturation) at the outlet of the desulfurization device 4 completely enters the bottom of the third gas-liquid direct contact heat exchanger 8, is mixed with the flue gas from the outlet of the second gas-liquid direct contact heat exchanger 7, and then is subjected to direct contact heat exchange with a top-down circulating solution (about 50-60 ℃, the concentration of which is determined according to the type of the solution and creates the lowest possible partial pressure of water vapor, taking LiBr as an example, the concentration of which is about 55%) in the third gas-liquid direct contact heat exchanger 8. The rear flue gas enters the smoke exhaust chimney 5 from the first output end (top outlet) of the third gas-liquid direct contact heat exchanger 8 through the sixth electromagnetic valve 22 and is discharged into the environment. Because the moisture content and the temperature of the flue gas are greatly reduced after absorption, the total heat is recovered, the dew point is greatly reduced, and the problem of wet smoke plume at the outlet of the smoke exhaust chimney 5 can be effectively solved. In the third gas-liquid direct contact heat exchanger 8, the circulating solution after absorption reaction is lifted by a third pump 16 to form a pressure head, then is divided into two branches, one branch passes through an eighth electromagnetic valve 24, the other branch passes through a third electromagnetic valve 19 and a third dividing wall type liquid-liquid heat exchanger 11, heat exchange is carried out on the circulating solution to return water from a heat supply network, and the two branches join and then pass through a first dividing wall type liquid-liquid heat exchanger 9 and then enter a first gas-liquid direct contact heat exchanger 6. In the first gas-liquid direct contact heat exchanger 6, medium-temperature flue gas (about 350 ℃) from the outlet of the denitration device 1 and solution are subjected to direct contact heat exchange, sensible heat is transferred from the flue gas to the solution, latent heat is transferred from the solution to the flue gas, and the generation process is carried out. After the pressure head of the solution at the second output end of the first gas-liquid direct contact heat exchanger 6 is lifted by the first pump 14, the solution exchanges heat with the solution from the third gas-liquid direct contact heat exchanger 8 through the first dividing wall type liquid-liquid heat exchanger 9, and then returns to the third gas-liquid direct contact heat exchanger 8. The first dividing wall type liquid-liquid heat exchanger 9 is used for sensible heat exchange between two solutions, improves the temperature of the solution from the third gas-liquid direct contact heat exchanger 8, strengthens the generation process, reduces the temperature of the solution from the first gas-liquid direct contact heat exchanger 6, and promotes the absorption process. The flue gas (about 120 ℃ and about 170 g/kg) at the first output end of the first gas-liquid direct contact heat exchanger 6 has a large amount of sensible heat and latent heat, and in order to realize the problem of total heat recovery and wall solution regeneration of the part of heat, circulating water (about 55 ℃ and equivalent moisture content of 114g/kg) is used for carrying out thermal mass absorption on the flue gas in the second gas-liquid direct contact heat exchanger 7, at the moment, the sensible heat and the latent heat are both transferred to the circulating water by the flue gas, an absorption process occurs, a large amount of moisture is condensed and discharged out of the system by a condensed water discharging device 25, and true latent heat recovery (the moisture in the flue gas is finally discharged out of the system in a liquid form) is realized. Circulating water after absorbing heat and absorbing mass in the second gas-liquid direct contact heat exchanger 7 enters the second partition type liquid-liquid heat exchanger 10 to be recycled and exchange heat with a heat supply network after a pressure head is lifted by a second pump 15, and then enters the second gas-liquid direct contact heat exchanger 7 to realize circulation. In all the processes, the first gas-liquid direct contact heat exchanger 6 carries out the generation process, the second gas-liquid direct contact heat exchanger 7 and the third gas-liquid direct contact heat exchanger 8 carry out the absorption process, the heat generated in the absorption process comes from the low-temperature high-humidity flue gas (about 60 ℃, about 80g/kg and close to saturation) to be treated and part of the generated medium-temperature flue gas (about 350 ℃), and the heat generated in the process is used for recovering and heating the heat supply network, so that the recovery and utilization of waste heat are realized. A small amount of flue gas used in the generation process is medium-temperature flue gas (about 350 ℃) from the front of the air preheater 2, so that gradient utilization of flue gas waste heat and quality improvement of low-temperature flue gas waste heat are realized (originally, about 60 ℃ flue gas is difficult to heat a heat supply network for recovery).
The invention relates to a full-open type absorption heat pump for flue gas waste heat full-heat gradient depth recovery, which comprises a flue gas loop, a solution loop, a circulating water loop and a heat supply network water loop. The full-heat deep recovery is realized on the low-temperature smoke exhaust of the boiler by using a solution loop, the solution after absorbing heat and moisture is regenerated by using a small amount of medium-temperature smoke in front of an air preheater, the smoke carrying a large amount of sensible heat and latent heat is subjected to the full-heat deep recovery through a circulating water loop, and all heat generated in the full-heat recovery process is supplied to a heat supply network for returning water. Compared with the traditional absorption heat pump in waste heat utilization, the fully-open system greatly reduces the manufacturing cost and the operation and maintenance difficulty because the system does not need a vacuum environment. The direct contact packed tower is used as a device for exchanging heat between solution/water and flue gas, so that the heat transfer capacity is improved, and the corrosion problem of the dividing wall type heat exchanger in waste heat utilization is thoroughly solved.
Claims (7)
1. The full-open type absorption heat pump for flue gas waste heat full-heat gradient deep recovery is characterized by comprising a flue gas loop, a solution loop, a circulating water loop and a heat supply network water loop, wherein the flue gas loop is used for conveying flue gas at the outlet of an economizer, the solution loop is used for realizing full-heat deep recovery of low-temperature exhaust smoke of a boiler, a small amount of medium-temperature flue gas is used for regenerating the solution after heat absorption and moisture absorption, the flue gas carrying a large amount of sensible heat and latent heat is subjected to full-heat deep recovery through the circulating water loop, and all heat generated in the full-heat recovery process is supplied to heat supply network return water in the heat supply network water loop.
2. The full-open type absorption heat pump for flue gas waste heat full-thermal gradient deep recovery according to claim 1, wherein the flue gas loop comprises a denitration device (1), an air preheater (2), an electric precipitator (3), a desulfurization device (4), a smoke exhaust chimney (5), a first gas-liquid direct contact heat exchanger (6), a second gas-liquid direct contact heat exchanger (7), a third gas-liquid direct contact heat exchanger (8), a first fan (12), a second fan (13), a first electromagnetic valve (17), a fifth electromagnetic valve (21), a sixth electromagnetic valve (22), a seventh electromagnetic valve (23) and related pipelines, wherein flue gas at an outlet of the coal economizer is input into an input end of the denitration device, an output end of the denitration device is connected with a first input end of the air preheater, a first output end of the air preheater is connected with an input end of the electric precipitator, and an output end of the electric precipitator is connected with an input end of the desulfurization device, the output end of the desulphurization device is connected with the input end of the smoke exhaust chimney through a seventh electromagnetic valve; in addition, the denitration device is connected with a first input end of the first gas-liquid direct contact heat exchanger through a first electromagnetic valve, a first output end of the first gas-liquid direct contact heat exchanger is connected with a first input end of the second gas-liquid direct contact heat exchanger, a first output end of the second gas-liquid direct contact heat exchanger is connected with a first input end of a third gas-liquid direct contact heat exchanger, and a first output end of the third gas-liquid direct contact heat exchanger is connected with an input end of the smoke exhaust chimney through a sixth electromagnetic valve; the output end of the desulfurization device is connected with the second input end of the third gas-liquid direct contact heat exchanger through a fifth electromagnetic valve; the first fan is connected with the second input end of the air preheater, and the second output end of the air preheater outputs hearth hot air; and the third fan is connected with the third input end of the air preheater, and the third output end of the air preheater outputs hot air of the coal mill.
3. The full open type absorption heat pump for flue gas waste heat full heat gradient depth recovery according to claim 2, wherein the first gas-liquid direct contact heat exchanger (6), the second gas-liquid direct contact heat exchanger (7) and the third gas-liquid direct contact heat exchanger (8) are all direct contact type packed towers, the packed towers are in a counter flow or cross flow mode, and the packing is bulk or regular high temperature and corrosion resistant packing.
4. The full open type absorption heat pump for flue gas waste heat full heat step depth recovery according to claim 1, wherein the solution loop comprises a first dividing wall type liquid-liquid heat exchanger (9), a third dividing wall type liquid-liquid heat exchanger (11), a first pump (14), a third pump (16), a third electromagnetic valve (19), an eighth electromagnetic valve (24) and related pipelines, wherein a second output end of a first gas-liquid direct contact heat exchanger (6) in the flue gas loop is connected with a first input end of the first dividing wall type liquid-liquid heat exchanger through the first pump, a first output end of the first dividing wall type liquid-liquid heat exchanger is connected with a third input end of the third gas-liquid direct contact heat exchanger, a second output end of the third gas-liquid direct contact heat exchanger is connected with an input end of the third pump, and one output end of the third pump is connected with a second input end of the first dividing wall type liquid-liquid heat exchanger through the eighth electromagnetic valve, the other path is connected with a first input end of a third dividing wall type liquid-liquid heat exchanger through a third electromagnetic valve, a first output end of the third dividing wall type liquid-liquid heat exchanger is connected with a second input end of the first dividing wall type liquid-liquid heat exchanger, and a second output end of the first dividing wall type liquid-liquid heat exchanger is connected with a second input end of a first gas-liquid direct contact heat exchanger in the smoke loop.
5. The full open type absorption heat pump for flue gas waste heat full heat step depth recovery according to claim 4, wherein the circulating working medium in the solution loop is a solution with a low water vapor partial pressure, such as LiCl, LiBr or CaCl2 solution, or an alcohol organic solution.
6. The full open type absorption heat pump for flue gas waste heat full heat step depth recovery according to claim 1, wherein the circulating water loop comprises a second divided wall type liquid-liquid heat exchanger (10), a second pump (15), a condensed water drainage device (25) and related pipelines, wherein a second output end of a second gas-liquid direct contact heat exchanger (7) in the flue gas loop is connected with a first input end of the second divided wall type liquid-liquid heat exchanger through the second pump, and a first output end of the second divided wall type liquid-liquid heat exchanger is connected with a second input port of the second gas-liquid direct contact heat exchanger in the flue gas loop; in addition, the condensed water discharging device is arranged at the lower part of the second gas-liquid direct contact heat exchanger in the flue gas loop and used for discharging the condensed water from the flue gas.
7. The full-open absorption heat pump for flue gas waste heat full-heat step depth recovery according to claim 1, wherein the heat supply network water loop comprises a second electromagnetic valve (18), a fourth electromagnetic valve (20) and related pipelines, the heat supply network backwater is respectively connected with the second input end of the second dividing wall type liquid-liquid heat exchanger (10) in the circulating water loop and the second input end of the third dividing wall type liquid-liquid heat exchanger (11) in the solution loop through the second electromagnetic valve and the fourth electromagnetic valve, and the second output end of the second dividing wall type liquid-liquid heat exchanger in the circulating water loop and the second output end of the third dividing wall type liquid-liquid heat exchanger in the solution loop are both connected with the heat supply network water supply.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113324347A (en) * | 2021-05-20 | 2021-08-31 | 浙江理工大学 | Double-absorption working medium heat storage type open type absorption heat exchange system |
| CN113324346A (en) * | 2021-05-20 | 2021-08-31 | 浙江理工大学 | Double-effect/two-stage open type absorption heat pump |
| WO2022141612A1 (en) * | 2021-01-03 | 2022-07-07 | 李华玉 | Dual-fuel high-temperature heat source |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106500122A (en) * | 2016-09-08 | 2017-03-15 | 中国科学院工程热物理研究所 | A kind of elimination coal fired power plant chimney white haze is while the system and method for Mist heat recovering and water |
-
2019
- 2019-12-03 CN CN201911219614.8A patent/CN111023076A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106500122A (en) * | 2016-09-08 | 2017-03-15 | 中国科学院工程热物理研究所 | A kind of elimination coal fired power plant chimney white haze is while the system and method for Mist heat recovering and water |
Non-Patent Citations (2)
| Title |
|---|
| 杨波等: "用于烟气全热回收的全开式吸收式热泵", 《东南大学学报（自然科学版）》 * |
| 王争荣等: "开式吸收热泵节能协同收水除尘系统研究", 《电力科技与环保》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022141612A1 (en) * | 2021-01-03 | 2022-07-07 | 李华玉 | Dual-fuel high-temperature heat source |
| CN113324347A (en) * | 2021-05-20 | 2021-08-31 | 浙江理工大学 | Double-absorption working medium heat storage type open type absorption heat exchange system |
| CN113324346A (en) * | 2021-05-20 | 2021-08-31 | 浙江理工大学 | Double-effect/two-stage open type absorption heat pump |
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Application publication date: 20200417 |