CN107476897B - Waste heat recovery system and method for LNG automobile engine - Google Patents
Waste heat recovery system and method for LNG automobile engine Download PDFInfo
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- CN107476897B CN107476897B CN201710858168.XA CN201710858168A CN107476897B CN 107476897 B CN107476897 B CN 107476897B CN 201710858168 A CN201710858168 A CN 201710858168A CN 107476897 B CN107476897 B CN 107476897B
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02G—HOT GAS OR COMBUSTION-PRODUCT POSITIVE-DISPLACEMENT ENGINE PLANTS; USE OF WASTE HEAT OF COMBUSTION ENGINES; NOT OTHERWISE PROVIDED FOR
- F02G5/00—Profiting from waste heat of combustion engines, not otherwise provided for
- F02G5/02—Profiting from waste heat of exhaust gases
- F02G5/04—Profiting from waste heat of exhaust gases in combination with other waste heat from combustion engines
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
- F01K23/00—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids
- F01K23/02—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled
- F01K23/06—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle
- F01K23/065—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle the combustion taking place in an internal combustion piston engine, e.g. a diesel engine
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
- F01K23/00—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids
- F01K23/02—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled
- F01K23/06—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle
- F01K23/10—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle with exhaust fluid of one cycle heating the fluid in another cycle
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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
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
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- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Engine Equipment That Uses Special Cycles (AREA)
Abstract
The invention discloses a waste heat recovery system for an LNG automobile engine and a recovery method thereof, which solve the technical problem of reasonably utilizing heat dissipated by automobile tail gas and engine cooling liquid, and effectively improving the fuel economy of the automobile by utilizing cold energy of LNG fuel. The invention comprises an organic Rankine cycle system for recovering the waste heat of engine tail gas and cooling liquid and an LNG fuel cold energy utilization and heating system, wherein the organic Rankine cycle system comprises a heat conducting oil circulation loop and an organic working medium circulation loop, the heat conducting oil circulation loop comprises a tail gas-heat conducting oil heat exchanger, a heat conducting oil circulation pump and an evaporator, a heat conducting oil outlet of the evaporator is connected with a heat conducting oil inlet of the tail gas-heat conducting oil heat exchanger through the heat conducting oil circulation pump, and the heat conducting oil outlet is connected with a heat conducting oil inlet of the evaporator. The invention reasonably utilizes the heat dissipated by the automobile exhaust and the cooling liquid, and fully utilizes the cold energy of LNG while recycling the waste heat of the engine.
Description
Technical Field
The invention relates to LNG automobile engine equipment, in particular to a waste heat recovery system for an LNG automobile engine and a recovery method thereof, belonging to the field of organic Rankine cycle for waste heat energy utilization.
Background
Liquefied natural gas (Liquefied Natural Gas, LNG) is a liquid formed when natural gas is purified and cooled to below-162 degrees celsius. The LNG has purer components than the gaseous natural gas, removes dust, acid gas, heavy hydrocarbon and other components, and is colorless, odorless, nontoxic and noncorrosive. Compared with a bus with a diesel engine, the LNG bus with the natural gas engine reduces the emission of 99% of carbon monoxide, 83% of hydrocarbon and 31% of oxynitride, has no emission of particulate matters and smoke dust, and basically contains no lead, sulfide, benzene and the like; meanwhile, the LNG automobile can effectively reduce noise pollution. In addition, LNG buses save about 22% of fuel costs relative to diesel vehicles, and LNG heavy trucks save about 15% of fuel costs relative to diesel heavy trucks. Therefore, the golden period of the LNG automobile industry, especially LNG heavy trucks and buses, will be the development bright point for the next few years under the dual driving of environmental and economic advantages.
In general, the thermal efficiency of an automobile engine can only reach about 30%, and the rest of heat is inevitably consumed by the following parts, including an engine cooling system (25%), an automobile exhaust system (40%) and other mechanical auxiliary equipment (5%) of the automobile. How to reasonably utilize the heat dissipated by the automobile exhaust and the cooling liquid, reduce the consumption of fuel by the automobile, effectively reduce the emission and reduce the pollution to the environment is an urgent problem to be solved in the development of automobile engines.
The Organic Rankine Cycle (ORC) system is a Rankine cycle system taking organic working medium as cycle working medium, and is an important technical means for recovering the waste heat energy of an automobile engine. However, the miniaturized and lightweight ORC system is a precondition for realizing the recovery of the residual heat energy of the LNG automobile engine, and the efficient heat exchange means, the efficient expander and the optimized system are important means for realizing the miniaturization and the lightweight of the ORC system, so that the ORC system is an important guarantee for successful application of the ORC system in the LNG automobile engine.
Disclosure of Invention
The invention aims to solve the technical problems of reasonably utilizing heat dissipated by automobile tail gas and engine cooling liquid and simultaneously utilizing cold energy of LNG fuel, thereby reducing fuel consumption of an automobile, effectively reducing emission and reducing environmental pollution.
In order to solve the technical problems, the invention adopts the following technical scheme: the waste heat recovery system for the LNG automobile engine comprises an organic Rankine cycle system for recovering waste heat of engine tail gas and cooling liquid and an LNG fuel cold energy utilization and heating system, wherein the organic Rankine cycle system comprises a heat conducting oil circulation loop and an organic working medium circulation loop, the heat conducting oil circulation loop comprises a tail gas-heat conducting oil heat exchanger, a heat conducting oil circulation pump and an evaporator, a heat conducting oil outlet of the evaporator is connected with a heat conducting oil inlet of the tail gas-heat conducting oil heat exchanger through the heat conducting oil circulation pump, and a heat conducting oil outlet of the tail gas-heat conducting oil heat exchanger is connected with a heat conducting oil inlet of the evaporator;
the organic working medium circulation loop comprises an expander, a heat regenerator, an air-cooled condenser, an LNG-organic working medium heat exchanger, an organic working medium circulation pump, an oil-organic working medium separator and a preheater, wherein an organic working medium outlet of the evaporator is connected with an inlet of the expander, and an outlet of the expander sequentially passes through the heat regenerator, the air-cooled condenser, the LNG-organic working medium heat exchanger, the organic working medium circulation pump and the heat regenerator and then is connected with an organic working medium inlet of the evaporator.
The LNG fuel cold energy utilization and heating system comprises a storage tank, a front replacement heat coil of an air-cooled condenser, an LNG-organic working medium heat exchanger, a heat exchange coil and an engine, wherein the storage tank is sequentially connected with the front replacement heat coil, the LNG-organic working medium heat exchanger, the heat exchange coil and the engine through pipelines.
The heat exchange coil is placed in an engine lubricating oil pool.
And the tail gas outlet of the engine is connected with the tail gas-heat conducting oil heat exchanger.
A bypass connected with the expander in parallel is arranged on a pipeline connected with an organic working medium outlet of the evaporator, an electromagnetic valve I is arranged on the bypass, and an electromagnetic valve II and an electromagnetic valve III are arranged at two ends of the expander; a pipeline connected with the heat regenerator in parallel is provided with an electromagnetic valve IV, and the pipelines connected with the expansion machine and the air-cooled condenser at two ends of the heat regenerator are respectively provided with an electromagnetic valve V and an electromagnetic valve VI; and a temperature sensor is also arranged on a pipeline connected with the organic working medium outlet of the evaporator.
And an oil-organic working medium separator is arranged between the organic working medium circulating pump and the heat regenerator.
The oil-organic working medium separator comprises a shell, wherein an inlet is formed in the upper part of the shell, an organic working medium outlet is formed in the lower part of the shell, an oil outlet is formed in one side of the shell, a baffle and a filler plate are arranged in the shell, the baffle is arranged below the inlet, and a gap is reserved between one side of the baffle and the inner wall of the shell; the packing plate is obliquely arranged in the shell; the baffle include diaphragm and swash plate, diaphragm and swash plate constitute horizontal "V" template, diaphragm right side links to each other with shells inner wall, leaves the clearance between left side and the shells inner wall, swash plate left side links to each other with the diaphragm and extends to the lower right side.
An oil level sensor is arranged in the shell above the packing plate, and a solenoid valve is arranged on a pipeline connected with the oil outlet; the filler plate is a super oleophobic material plate; the inner wall of the pipe of the air-cooled condenser is provided with an super-oleophobic coating.
The waste heat recovery method for the LNG automobile engine waste heat recovery system is characterized by comprising the following steps of: (1) the tail gas of the engine enters a tail gas-heat conducting oil heat exchanger of a heat conducting oil circulation loop to heat conducting oil; the heated heat conducting oil heats the high-pressure organic working medium through an evaporator, so that the high-pressure organic working medium is changed into high-temperature and high-pressure superheated steam; (2) the high-temperature high-pressure superheated steam enters an expander to expand and do work, the high-temperature high-pressure superheated steam becomes low-pressure organic working medium steam after the expansion and doing work, the low-pressure organic working medium steam enters a regenerator to be released, then enters an air-cooled condenser to be cooled into low-pressure liquid organic working medium, and then enters an LNG-organic working medium heat exchanger to be further cooled into low-pressure liquid organic working medium; (3) the low-pressure liquid organic working medium is pressurized by the organic working medium circulating pump and becomes a high-pressure liquid organic working medium; (4) the high-pressure liquid organic working medium enters an engine cooling liquid-organic working medium preheater, absorbs heat of the engine cooling liquid, then enters a regenerator to absorb heat of low-pressure organic working medium steam, and then enters an organic working medium evaporator to be heated into high-temperature high-pressure superheated steam to form an organic Rankine cycle loop; (5) the LNG fuel is cooled by heat exchange with the air entering the air-cooled condenser to increase the temperature, and the air temperature is reduced, then the LNG fuel absorbs the heat of the organic working medium in the LNG-organic working medium heat exchanger and then enters the heat exchange coil, absorbs the heat of engine lubricating oil to further increase the temperature of the LNG, and finally is injected into the engine for combustion.
In the step (1), the heat conduction oil in the tail gas-heat conduction oil heat exchanger is heated to 300-350 ℃, and the temperature of the heat conduction oil in the evaporator is reduced to below 150 ℃; and (3) separating the mixed lubricating oil from the high-pressure liquid organic working medium through an oil-organic working medium separator, and then feeding the lubricating oil into an engine cooling liquid-organic working medium preheater.
The invention reasonably utilizes the heat dissipated by the automobile tail gas and the cooling liquid, effectively improves the fuel economy of the automobile, reduces the fuel consumption of the automobile, simultaneously effectively reduces the emission and reduces the environmental pollution. In addition, LNG also contains larger cold energy, and the part of cold energy is fully utilized while the waste heat of the engine is recycled, so that the difference between the automobile engine taking LNG as fuel and the conventional diesel engine is the largest.
Drawings
FIG. 1 is a schematic diagram of a waste heat recovery system of an LNG automobile engine according to the present invention;
fig. 2 is a schematic diagram of the structure of the oil-organic working separator of the present invention.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without any inventive effort, are intended to be within the scope of the invention.
As shown in fig. 1 and fig. 2, a waste heat recovery system for an LNG automobile engine comprises an organic rankine cycle system for recovering waste heat of engine tail gas and cooling liquid, and an LNG fuel cold energy utilization and heating system, wherein the organic rankine cycle system comprises a heat transfer oil circulation loop and an organic working medium circulation loop, the heat transfer oil circulation loop comprises a tail gas-heat transfer oil heat exchanger 28, a heat transfer oil circulation pump 27 and an evaporator 26, a heat transfer oil outlet of the evaporator 26 is connected with a heat transfer oil inlet of the tail gas-heat transfer oil heat exchanger 28 through the heat transfer oil circulation pump 27, and a heat transfer oil outlet of the tail gas-heat transfer oil heat exchanger 28 is connected with a heat transfer oil inlet of the evaporator 26; the heat conducting oil is pumped from the evaporator 26 to the tail gas-heat conducting oil heat exchanger 28 by the heat conducting oil circulating pump 27, the heat conducting oil absorbs the heat of the tail gas of the engine in the tail gas-heat conducting oil heat exchanger 28, the heat conducting oil is heated to 300-350 ℃, then the high-pressure organic working medium is heated in the evaporator 26 to be changed into high-temperature and high-pressure superheated steam, and the temperature of the heat conducting oil in the evaporator 26 is reduced to be lower than 150 ℃ and then pumped into the tail gas-heat conducting oil heat exchanger 28, so that a heat conducting oil circulating loop is formed.
The organic working medium circulation loop comprises an expander 21, a heat regenerator 25, an air-cooled condenser 13, an LNG-organic working medium heat exchanger 10, an organic working medium circulation pump 8, an oil-organic working medium separator 6 and a preheater 5, wherein an organic working medium outlet of the evaporator 26 is connected with an inlet of the expander 21, and an outlet of the expander 21 sequentially passes through the heat regenerator 25, the air-cooled condenser 13, the LNG-organic working medium heat exchanger 10, the organic working medium circulation pump 8 and the heat regenerator 25 and then is connected with an organic working medium inlet of the evaporator 26. The expander 21 is a rotary positive displacement expander; a generator 20 is also connected to the expander 21. The work output by the expander 21 can be generated by the generator 20 or can be coupled to the power system of the automobile.
The high-pressure organic working medium is heated into superheated steam of the high-temperature high-pressure organic working medium by heat conduction oil in the evaporator 26, and the superheated steam of the high-temperature high-pressure organic working medium enters the expander 21 to expand and do work so as to drive the generator 20 to generate electricity; the superheated steam of the high-temperature high-pressure organic working medium flows out of the expander to be changed into low-pressure organic working medium steam, and is mixed with lubricating oil drops injected into the expander; after the low-pressure organic working medium steam is released in the regenerator 25, the low-pressure organic working medium steam enters the air-cooled condenser 13 to be cooled into low-pressure liquid organic working medium, and then enters the LNG-organic working medium heat exchanger 10 to be further cooled into low-pressure liquid organic working medium with a certain supercooling degree; the low-pressure liquid organic working medium is pressurized by the organic working medium circulating pump 8 to become a high-pressure liquid organic working medium. After the mixed lubricating oil is separated in the oil-organic working medium separator 6, the high-pressure liquid organic working medium enters the engine cooling liquid-organic working medium preheater 5, absorbs the heat of the engine cooling liquid, enters the regenerator 25, absorbs the heat of the low-pressure organic working medium steam, and then further increases in temperature, enters the organic working medium evaporator 26, and is heated to be high-temperature and high-pressure superheated steam to form an organic Rankine cycle loop.
The cold energy of the LNG is utilized to reduce the temperature of the air entering the air-cooled condenser 13 in the heat exchange coil 10 and to increase the supercooling of the organic working fluid within the LNG-organic working fluid heat exchanger 10.
The LNG fuel cold energy utilization and heating system comprises a storage tank 11, a front replacement heat coil 12 of an air-cooled condenser 13, an LNG-organic working medium heat exchanger 10, a heat exchange coil 3 and an engine 1, wherein the storage tank 11 is sequentially connected with the front replacement heat coil 12, the LNG-organic working medium heat exchanger 10, the heat exchange coil 3 and the engine 1 through pipelines.
The heat exchange coil 3 is arranged in the engine lubricating oil tank 2; the LNG fuel flowing in the heat exchange coil 3 placed in the engine lubricating oil pool 2 is heated by the engine lubricating oil to raise its temperature. The low-temperature LNG fuel flows out of the storage tank 11, flows in the heat exchange coil 12 arranged at the air inlet of the air-cooled condenser 13, increases the temperature through heat exchange with air entering the air-cooled condenser 13, reduces the air temperature, absorbs the heat of the organic working medium in the LNG-organic working medium heat exchanger 10, enters the heat exchange coil 3 arranged in the engine lubricating oil tank 2, absorbs the heat of engine lubricating oil, further increases the LNG temperature, and finally is injected into the engine 1 for combustion.
The exhaust outlet of the engine 1 is connected with an exhaust-heat transfer oil heat exchanger 28. The tail gas of the engine enters the tail gas-heat transfer oil heat exchanger 28 to heat the heat transfer oil.
A bypass 18 connected with the expander 21 in parallel is arranged on a pipeline connected with an organic working medium outlet of the evaporator 26, an electromagnetic valve I24 is arranged on the bypass 18, and an electromagnetic valve II22 and an electromagnetic valve III19 are arranged at two ends of the expander 21; a pipeline connected with the heat regenerator 25 in parallel is provided with an electromagnetic valve IV16, and a pipeline connected with the expansion machine 21 and the air-cooled condenser 13 at two ends of the heat regenerator 25 is respectively provided with an electromagnetic valve V17 and an electromagnetic valve VI15; a temperature sensor 23 is also provided on the line connected to the organic working fluid outlet of the evaporator 26. When the LNG engine 1 is just started, idling or the temperature sensor 23 detects that the quality of the organic working medium steam flowing out of the evaporator 26 is not high, the solenoid valve V17, the solenoid valve VI15, the solenoid valve II22 and the solenoid valve III19 are closed, the solenoid valve IV16 and the solenoid valve I24 are opened, and the organic working medium steam directly enters the air-cooled condenser 13 to be condensed into a liquid organic working medium without passing through the expander 21 and the regenerator 25.
An oil-organic working medium separator 6 is also arranged between the organic working medium circulating pump 8 and the regenerator 25. The lubricating oil in the organic rankine cycle system and the high-pressure liquid organic working fluid are separated in the oil-organic working fluid separator 6.
The oil-organic working medium separator 6 comprises a shell 68, wherein an inlet 62 is formed in the upper part of the shell 68, an organic working medium outlet 67 is formed in the lower part of the shell 68, an oil outlet 64 is formed in one side of the shell 68, a baffle 61 and a packing plate 66 are arranged in the shell 68, the baffle 61 is arranged below the inlet 62, and a gap is reserved between one side of the baffle 61 and the inner wall of the shell 68; the packing plate 66 is obliquely arranged in the shell 68; the baffle 61 comprises a transverse plate 69 and an inclined plate 70, wherein the transverse plate 69 and the inclined plate 70 form a transverse V-shaped plate, the right side of the transverse plate 69 is connected with the inner wall of the shell 68, a gap is reserved between the left side of the transverse plate 69 and the inner wall of the shell 68, and the left side of the inclined plate 70 is connected with the transverse plate 69 and then extends downwards to the right. The cross plate 69 is used for guiding the high-pressure liquid organic working medium-lubricating oil mixture to flow from the inlet to the inner wall surface on one side of the shell, so that the mixture flows downwards onto the packing plate 66 along the inner wall of the shell, the mixture is prevented from flowing too fast, the separation of lubricating oil is prevented from being influenced, and liquid splashing is prevented; and then flows from the high position to the low position of the packing plate, so that the separation time and the separation area of the lubricating oil are increased, the separation process of the liquid organic working medium-lubricating oil mixture is more mild, and the separation is more thorough. The provision of the swash plate 70 prevents the liquid organic medium-lubricating oil mixture from flowing too fast to cause the liquid level thereof to rise, and liquid is gathered, affecting the separation effect and efficiency.
The packing plate 66 and the sloping plate 70 are inclined to the right and below, and a gap is reserved between the right end of the sloping plate 70 and the shell 68. The separated lubricating oil is accumulated upward through the gap, and the oil level sensor 63 is disposed above the lowest point of the swash plate 70, and when the lubricating oil reaches a certain height, the oil level sensor 63 detects that the oil level opens the electromagnetic valve 65 to drain oil.
An oil level sensor 63 is also arranged in the shell 68 above the packing plate 66, and a solenoid valve 65 is arranged on a pipeline connected with the oil outlet 64. The high-pressure liquid organic working medium-lubricating oil mixture enters the oil-organic working medium separator 6 from the inlet 62, and flows downwards along the inner wall surface of the oil-organic working medium separator 6 due to the existence of the baffle 61, so that the flow speed is reduced, and the buffer effect is achieved; when the organic working medium-lubricating oil flows through the surface of the packing plate 66, the organic working medium passes through the packing plate 66 and then flows out from the organic working medium outlet 67, whereas the lubricating oil cannot pass through the packing plate 66 and is accumulated above the packing plate 66. When the oil level sensor 63 detects the oil level, the solenoid valve 65 is opened, and the lubricating oil flows out from the oil outlet 64.
The filler plate 66 is a super oleophobic material plate; the inner wall of the pipe of the air-cooled condenser 13 is provided with an super-oleophobic coating.
A waste heat recovery method for an LNG automotive engine waste heat recovery system, comprising the steps of: (1) the tail gas of the engine 1 enters the tail gas-heat conducting oil heat exchanger 28 of the heat conducting oil circulation loop to heat conducting oil; the heated heat conducting oil heats the high-pressure organic working medium through the evaporator 26, so that the high-pressure organic working medium is changed into high-temperature and high-pressure superheated steam; (2) the high-temperature high-pressure superheated steam enters the expander 21 to expand and do work, the high-temperature high-pressure superheated steam becomes low-pressure organic working medium steam after the expansion work, the low-pressure organic working medium steam enters the regenerator 25 to be released, then enters the air-cooled condenser 13 to be cooled into low-pressure liquid organic working medium, and then enters the LNG-organic working medium heat exchanger 10 to be further cooled into low-pressure liquid organic working medium; (3) the low-pressure liquid organic working medium is pressurized by the organic working medium circulating pump 8 and becomes high-pressure liquid organic working medium; (4) the high-pressure liquid organic working medium enters the engine cooling liquid-organic working medium preheater 5, absorbs the heat of the engine cooling liquid, then enters the regenerator 25, absorbs the heat of low-pressure organic working medium steam, and then enters the organic working medium evaporator 26, and is heated to be high-temperature high-pressure superheated steam to form an organic Rankine cycle loop; (5) the temperature of the LNG fuel is reduced while the temperature is increased by heat exchange with the air entering the air-cooled condenser 13, then the LNG fuel enters the heat exchange coil 3 after absorbing the heat of the organic working medium in the LNG-organic working medium heat exchanger 10, the heat of engine lubricating oil is absorbed to further increase the temperature of the LNG, and finally the LNG fuel is injected into the engine 1 for combustion. The high-pressure organic working medium is the organic working medium after being pressurized by the organic working medium circulating pump.
In the step (1), the heat transfer oil in the tail gas-heat transfer oil heat exchanger 28 is heated to 300-350 ℃, and the temperature of the heat transfer oil in the evaporator 26 is reduced to below 150 ℃; and (3) separating the mixed lubricating oil from the high-pressure liquid organic working medium through an oil-organic working medium separator 6, and then feeding the lubricating oil into an engine cooling liquid-organic working medium preheater 5.
Claims (8)
1. A waste heat recovery system for LNG automobile engine, its characterized in that: the system comprises an organic Rankine cycle system for recovering engine tail gas and cooling liquid waste heat and an LNG fuel cold energy utilization and heating system, wherein the organic Rankine cycle system comprises a heat conducting oil circulation loop and an organic working medium circulation loop, the heat conducting oil circulation loop comprises a tail gas-heat conducting oil heat exchanger (28), a heat conducting oil circulation pump (27) and an evaporator (26), a heat conducting oil outlet of the evaporator (26) is connected with a heat conducting oil inlet of the tail gas-heat conducting oil heat exchanger (28) through the heat conducting oil circulation pump (27), and a heat conducting oil outlet of the tail gas-heat conducting oil heat exchanger (28) is connected with a heat conducting oil inlet of the evaporator (26);
the organic working medium circulation loop comprises an expander (21), a heat regenerator (25), an air-cooled condenser (13), an LNG-organic working medium heat exchanger (10), an organic working medium circulation pump (8), an oil-organic working medium separator (6) and a preheater (5), wherein an organic working medium outlet of the evaporator (26) is connected with an inlet of the expander (21), and an outlet of the expander (21) sequentially passes through the heat regenerator (25), the air-cooled condenser (13), the LNG-organic working medium heat exchanger (10), the organic working medium circulation pump (8) and the heat regenerator (25) and then is connected with an organic working medium inlet of the evaporator (26);
the LNG fuel cold energy utilization and heating system comprises a storage tank (11), a front replacement heat coil (12) of an air-cooled condenser (13), an LNG-organic working medium heat exchanger (10), a heat exchange coil (3) and an engine (1), wherein the storage tank (11) is sequentially connected with the front replacement heat coil (12), the LNG-organic working medium heat exchanger (10), the heat exchange coil (3) and the engine (1) through pipelines;
an oil-organic working medium separator (6) is arranged between the organic working medium circulating pump (8) and the heat regenerator (25).
2. The waste heat recovery system for an LNG automotive engine of claim 1, wherein: the heat exchange coil (3) is arranged in the engine lubricating oil tank (2).
3. The waste heat recovery system for an LNG automotive engine of claim 1, wherein: the tail gas outlet of the engine (1) is connected with a tail gas-heat conducting oil heat exchanger (28).
4. The waste heat recovery system for an LNG automotive engine of claim 1, wherein: a bypass (18) connected with the expander (21) in parallel is arranged on a pipeline connected with an organic working medium outlet of the evaporator (26), an electromagnetic valve I (24) is arranged on the bypass (18), and an electromagnetic valve II (22) and an electromagnetic valve III (19) are arranged at two ends of the expander (21); a solenoid valve IV (16) is arranged on a pipeline connected with the heat regenerator (25) in parallel, and a solenoid valve V (17) and a solenoid valve VI (15) are respectively arranged on pipelines connected with the expansion machine (21) and the air-cooled condenser (13) at two ends of the heat regenerator (25); a temperature sensor (23) is also arranged on a pipeline connected with the organic working medium outlet of the evaporator (26).
5. The waste heat recovery system for an LNG automotive engine of claim 1, wherein: the oil-organic working medium separator (6) comprises a shell (68), wherein an inlet (62) is formed in the upper portion of the shell (68), an organic working medium outlet (67) is formed in the lower portion of the shell, an oil outlet (64) is formed in one side of the shell (68), a baffle (61) and a filler plate (66) are arranged in the shell (68), the baffle (61) is arranged below the inlet (62), and a gap is reserved between one side of the baffle (61) and the inner wall of the shell (68); the packing plate (66) is obliquely arranged in the shell (68); the baffle (61) comprises a transverse plate (69) and an inclined plate (70), wherein the transverse plate (69) and the inclined plate (70) form a transverse V-shaped plate, the right side of the transverse plate (69) is connected with the inner wall of the shell (68), a gap is reserved between the left side of the transverse plate and the inner wall of the shell (68), and the left side of the inclined plate (70) is connected with the transverse plate (69) and then extends downwards right.
6. The waste heat recovery system for an LNG car engine of claim 5, wherein: an oil level sensor (63) is also arranged in the shell (68) above the packing plate (66), and a solenoid valve (65) is arranged on a pipeline connected with the oil outlet (64); the filler plate (66) is a super-oleophobic material plate; the inner wall of the pipe of the air-cooled condenser (13) is provided with an super-oleophobic coating.
7. The heat recovery method for an LNG car engine heat recovery system according to any one of claims 1-6, characterized by comprising the steps of: (1) a tail gas-heat conducting oil heat exchanger (28) of tail gas of the engine (1) entering a heat conducting oil circulation loop heats heat conducting oil; the heated heat conducting oil heats the high-pressure organic working medium through an evaporator (26) to change the high-pressure organic working medium into high-temperature and high-pressure superheated steam; (2) the high-temperature high-pressure superheated steam enters an expander (21) to expand and do work, the high-temperature high-pressure superheated steam becomes low-pressure organic working medium steam after the expansion work, the low-pressure organic working medium steam enters a regenerator (25) to release heat, then enters an air-cooled condenser (13) to be cooled into low-pressure liquid organic working medium, and then enters an LNG-organic working medium heat exchanger (10) to be further cooled into low-pressure liquid organic working medium; (3) the low-pressure liquid organic working medium is pressurized by an organic working medium circulating pump (8) and becomes a high-pressure liquid organic working medium; (4) the high-pressure liquid organic working medium enters an engine cooling liquid-organic working medium preheater (5), absorbs heat of the engine cooling liquid, then enters a regenerator (25), absorbs heat of low-pressure organic working medium steam, and then enters an organic working medium evaporator (26), and is heated to be high-temperature high-pressure superheated steam to form an organic Rankine cycle loop; (5) the LNG fuel is cooled by heat exchange with the air entering the air-cooled condenser (13) to increase the temperature, and the air temperature is reduced, then the LNG fuel absorbs the heat of the organic working medium in the LNG-organic working medium heat exchanger (10) and then enters the heat exchange coil (3), absorbs the heat of engine lubricating oil to further increase the LNG temperature, and finally is sprayed into the engine (1) for combustion.
8. The method for recovering waste heat of LNG automobile engine waste heat according to claim 7, wherein in the step (1), the heat transfer oil is heated to 300-350 ℃ in the tail gas-heat transfer oil heat exchanger (28), and the temperature of the heat transfer oil is reduced to below 150 ℃ in the evaporator (26); and (3) separating the mixed lubricating oil from the high-pressure liquid organic working medium through an oil-organic working medium separator (6), and then feeding the lubricating oil into an engine cooling liquid-organic working medium preheater (5).
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203824198U (en) * | 2014-02-20 | 2014-09-10 | 武汉三江航天远方科技有限公司 | Marine LNG (Liquefied Natural Gas) cold energy and flue gas waste heat comprehensive utilization system |
| CN105003328A (en) * | 2015-07-21 | 2015-10-28 | 同济大学 | Combined cooling and power system for recycling waste heat of automobile tail gas |
| DE102015012673A1 (en) * | 2015-09-30 | 2016-04-07 | Daimler Ag | Apparatus for waste heat recovery |
| CN106285896A (en) * | 2015-05-26 | 2017-01-04 | 金益翔（天津）新能源科技有限公司 | The LNG engine-cooling system of recyclable cold energy |
| CN207161223U (en) * | 2017-09-21 | 2018-03-30 | 郑州轻工业学院 | A kind of residual neat recovering system for LNG automobile engines |
-
2017
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203824198U (en) * | 2014-02-20 | 2014-09-10 | 武汉三江航天远方科技有限公司 | Marine LNG (Liquefied Natural Gas) cold energy and flue gas waste heat comprehensive utilization system |
| CN106285896A (en) * | 2015-05-26 | 2017-01-04 | 金益翔（天津）新能源科技有限公司 | The LNG engine-cooling system of recyclable cold energy |
| CN105003328A (en) * | 2015-07-21 | 2015-10-28 | 同济大学 | Combined cooling and power system for recycling waste heat of automobile tail gas |
| DE102015012673A1 (en) * | 2015-09-30 | 2016-04-07 | Daimler Ag | Apparatus for waste heat recovery |
| CN207161223U (en) * | 2017-09-21 | 2018-03-30 | 郑州轻工业学院 | A kind of residual neat recovering system for LNG automobile engines |
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