CN104197186A - BOG recycling system of LNG gas station and realizing method of BOG recycling system - Google Patents
BOG recycling system of LNG gas station and realizing method of BOG recycling system Download PDFInfo
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- CN104197186A CN104197186A CN201410429980.7A CN201410429980A CN104197186A CN 104197186 A CN104197186 A CN 104197186A CN 201410429980 A CN201410429980 A CN 201410429980A CN 104197186 A CN104197186 A CN 104197186A
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Abstract
The invention discloses a BOG recycling system of an LNG gas station and a realizing method of the BOG recycling system, and solves the problem of great energy waste and economic loss which are caused by emptying of excessive BOG gas in the prior art. The BOG recycling system comprises an LNG storage pot, a BOG compressor, an after-condenser, an immersed pump, a first distributor, a second distributor, a third distributor and a throttling valve. Due to reasonable connection matching of the equipment, BOG can be cooled and liquefied by original cold energy of LNG, so that investment of cooling equipment is greatly lowered, and the cost is reduced; meanwhile, the recycled BOG can be fully used; the phenomena of environment pollution and resource waste which are caused by BOG emptying are avoided.
Description
Technical field
The present invention relates to a kind of LNG BOG of gas station recycling system and its implementation.
Background technique
In LNG Industry Chain, the conventional method of treatments B OG gas has following four kinds:
(1) BOG in storage tank is back to LNG tank car and supplements the tank car pressure drop producing while unloading gas, this method technique is simple, makes full use of energy, without the external world, provides energy consumption, is suitable for using when LNG tank car is unloaded.
(2) by the BOG of generation, directly send torch burning, when BOG amount too much can not bear torch, directly enter atmosphere.But this method waste resource, damages environment, and easily accidents caused, in emergency circumstances use that can only be outside gas station.
(3) by compressor, BOG is compressed to after certain pressure, the LNG direct contact heat transfer under uniform pressure with output, is condensed into LNG and sends.
(4) by compressor, directly BOG is compressed, export after reaching the required pressure of outer defeated pipe network, this method is to reclaim BOG with gas form.The method technique is simple, investment cost is low, and this method is that BOG is inputed to gas distributing system, is therefore applicable to the BOG amount that produces little, joins or have the LNG gas station of personal gas with gas line network.
YuLNG receiving station compares, and the BOG total amount producing in gas station is little, and discontinuous, and therefore inconvenience adopts the method for BOG compressor, and utilizes BOG heater and EAG heater to process.In at present domestic LNG gas station running, when system pressure reaches certain value, storage tank gas phase pipeline direct-operated regulator is opened, and in storage tank, BOG leads to BOG heater, enters rock gas knock out drum and stores, for gas in station.When system pressure is greater than setting value, the safety valve in system is opened, and the cryogenic gas in delivery system reduces system running pressure, guarantees security of system; The cryogenic gas wherein discharging carries out emptying after EAG heater is heated into normal-temperature natural-gas.Due to the excessive BOG gas of traditional LNG gas station emptying, cause huge energy waste and economic loss.
Summary of the invention
The object of the present invention is to provide a kind of LNG BOG of gas station recycling system, solve the excessive BOG gas of prior art emptying, cause the problem of huge energy waste and economic loss.
To achieve these goals, the technical solution used in the present invention is as follows:
The BOG of LNG gas station recycling system, comprises LNG storage tank, BOG compressor, after-condenser, immersed pump, the first distributor, the second distributor, the 3rd distributor;
Wherein, described LNG storage tank gaseous phase outlet is connected with heat exchanger the first import, the import of BOG compressor is connected with the first outlet of heat exchanger, and the outlet of BOG compressor is connected with the second import of heat exchanger, and the second outlet of heat exchanger is connected with the first import of after-condenser; The first outlet of after-condenser is connected with two imports of the first distributor respectively with the second outlet, and the outlet of the first distributor is connected with the import of LNG storage tank; The first import of heat exchanger communicates with the first outlet, and the second import communicates with the second outlet;
LNG storage tank liquid-phase outlet is connected with immersed pump import, immersed pump outlet is connected with the import of the second distributor, the first outlet of the second distributor is connected with after-condenser the second import, the second outlet of the second distributor is connected with the import of the 3rd distributor, and two outlets of the 3rd distributor are for being connected with two filling machines; The first import of after-condenser communicates with the first outlet, and the second import communicates with the second outlet;
Between described the first distributor and LNG storage tank, be also provided with throttle valve.
The implementation method of the above-mentioned LNG BOG of gas station recycling system, comprises the following steps:
The BOG of recovery is passed in heat exchanger and heated up, then pass into and in BOG compressor, carry out supercharging, then return to heat exchanger and carry out heat exchange with the BOG newly entering, finally pass in after-condenser;
LNG in LNG storage tank must be crossed to cold LNG after by immersed pump supercharging, then the cold LNG of mistake is passed in the second distributor, the second distributor is crossed cold LNG after just can supercharging and is distributed, and a part passes into after-condenser;
The cold LNG of mistake and the BOG that enter in after-condenser carry out heat exchange, then condensed BOG is passed in the first distributor, simultaneously by with BOG heat exchange after the cold LNG of mistake pass in the first distributor, the two is mixed, then is conveyed in LNG storage tank by throttle valve;
The another part distributing by the second distributor is crossed cold LNG and is passed in the 3rd distributor, and the 3rd distributor is divided into two-way, is delivered directly in filling machine.
The present invention compared with prior art, has the following advantages and beneficial effect:
The present invention does not use outer refrigerant feeding to the BOG processing of lowering the temperature, and utilizes the cold energy of low temperature LNG self just can reach condensation requirement, saves equipment investment.LNG after heat exchange finally still can recycle in LNG storage tank in re-injection; Saved widely cost.
Accompanying drawing explanation
Fig. 1 is structural representation of the present invention.
Wherein, the component name that in accompanying drawing, mark is corresponding is called: 1-LNG storage tank, 2-heat exchanger, 3-BOG compressor, 4-after-condenser, 5-immersed pump, 6-the first distributor, 7-the second distributor, 8-the 3rd distributor, 9-throttle valve.
Embodiment
Below in conjunction with drawings and Examples, the invention will be further described, and embodiments of the present invention include but not limited to the following example.
Embodiment
As shown in Figure 1, the BOG of LNG gas station recycling system, comprises LNG storage tank 1, heat exchanger 2, BOG compressor 3, after-condenser 4, immersed pump 5, the first distributor 6, the second distributor 7, the 3rd distributor 8;
Wherein, the gaseous phase outlet of described LNG storage tank is connected with heat exchanger the first import, the import of BOG compressor is connected with the first outlet of heat exchanger, and the outlet of BOG compressor is connected with the second import of heat exchanger, and the second outlet of heat exchanger is connected with the first import of after-condenser; The first outlet of after-condenser is connected with two imports of the first distributor respectively with the second outlet, and the outlet of the first distributor is connected with the import of LNG storage tank; The first import of heat exchanger communicates with the first outlet, and the second import communicates with the second outlet;
The liquid-phase outlet of LNG storage tank is connected with immersed pump import, immersed pump outlet is connected with the import of the second distributor, the first outlet of the second distributor is connected with after-condenser the second import, the second outlet of the second distributor is connected with the import of the 3rd distributor, and two outlets of the 3rd distributor are for being connected with two filling machines; The first import of after-condenser communicates with the first outlet, and the second import communicates with the second outlet;
Between described the first distributor and LNG storage tank, be also provided with throttle valve 9.
Wherein, heat exchanger be for the BOG to after supercharging with also not the BOG after supercharging carry out heat exchange; BOG compressor is for BOG is carried out to supercharging, makes BOG become pressurized gas; Immersed pump, due to LNG is carried out to supercharging, makes LNG become cold LNG; After-condenser is for crossing the heat exchange between cold LNG and high pressure BOG, with LNG condensation BOG, makes BOG liquefaction; Throttle valve is for reducing from the first distributor LNG pressure out; The first distributor is for BOG is mixed with LNG; The second distributor is for LNG is distributed and makes a part enter after-condenser, and a part enters the 3rd distributor; The 3rd distributor is for LNG is distributed into two-way, supplies respectively two filling machines.
It is in order LNG to be carried out to supercharging (temperature is substantially constant), to make LNG have certain Subcoold temperature, being cold LNG that the present invention arranges immersed pump; Again the cold LNG of mistake is passed into after-condenser, utilizes the cold of crossing of LNG to carry out condensation BOG, that is to say the pressurization by LNG, become overcooled liquid, then with by the high pressure BOG heat exchange after BOG compressor boost, BOG is liquefied completely; The present invention has adopted the cold energy of LNG self, has avoided utilizing extraneous refrigeration agent, reduction widely cost.BOG and LNG through after-condenser mix by throttle valve step-down re-injection and recycle in LNG storage tank in the first distributor.
The implementation method of the above-mentioned LNG BOG of gas station recycling system, comprises the following steps:
By the BOG process reclaiming, then pass into and in BOG compressor, carry out supercharging, then return to heat exchanger and carry out heat exchange (heating newly entering BOG in heat exchanger) with the BOG newly entering, finally pass in after-condenser;
LNG in LNG storage tank must be crossed to cold LNG after by immersed pump supercharging, then the cold LNG of mistake is passed in the second distributor, the second distributor is crossed cold LNG after just can supercharging and is distributed, and a part passes into after-condenser;
The cold LNG of mistake and the BOG that enter in after-condenser carry out heat exchange, then condensed BOG is passed in the first distributor, simultaneously by with BOG heat exchange after the cold LNG of mistake pass in the first distributor, the two is mixed, then is conveyed in LNG storage tank by throttle valve;
The another part distributing by the second distributor is crossed cold LNG and is passed in the 3rd distributor, and the 3rd distributor is divided into two-way, is delivered directly in filling machine.
The present invention coordinates by rational equipment, can make full use of the original cold energy of LNG BOG is lowered the temperature, liquefied, thereby reduce widely the input of cooling equipment, has reduced cost; The BOG of recovery can be made full use of, avoid BOG emptying, cause environmental pollution simultaneously, and the waste of resource.
According to above-described embodiment, just can realize well the present invention.What deserves to be explained is; under prerequisite based on said structure design, for solving same technical problem, even if some that make in the present invention are without substantial change or polishing; the essence of the technological scheme adopting is still the same with the present invention, therefore it also should be in protection scope of the present invention.
Claims (2)
- The BOG of 1.LNG gas station recycling system, it is characterized in that, comprise LNG storage tank (1), heat exchanger (2), BOG compressor (3), after-condenser (4), immersed pump (5), the first distributor (6), the second distributor (7), the 3rd distributor (8);Wherein, described LNG storage tank gaseous phase outlet is connected with heat exchanger the first import, the import of BOG compressor is connected with the first outlet of heat exchanger, and the outlet of BOG compressor is connected with the second import of heat exchanger, and the second outlet of heat exchanger is connected with the first import of after-condenser; The first outlet of after-condenser is connected with two imports of the first distributor respectively with the second outlet, and the outlet of the first distributor is connected with the import of LNG storage tank; The first import of heat exchanger communicates with the first outlet, and the second import communicates with the second outlet;LNG storage tank liquid-phase outlet is connected with immersed pump import, immersed pump outlet is connected with the import of the second distributor, the first outlet of the second distributor is connected with after-condenser the second import, the second outlet of the second distributor is connected with the import of the 3rd distributor, and two outlets of the 3rd distributor are for being connected with two filling machines; The first import of after-condenser communicates with the first outlet, and the second import communicates with the second outlet;Between described the first distributor and LNG storage tank, be also provided with throttle valve (9).
- 2. the implementation method of the LNG BOG of gas station recycling system claimed in claim 1, is characterized in that, comprises the following steps:The BOG of recovery is passed in heat exchanger and heated up, then pass into and in BOG compressor, carry out supercharging, then return to heat exchanger and carry out heat exchange with the BOG newly entering, finally pass in after-condenser;LNG in LNG storage tank must be crossed to cold LNG after by immersed pump supercharging, then the cold LNG of mistake is passed in the second distributor, the second distributor is crossed cold LNG after just can supercharging and is distributed, and a part passes into after-condenser;The cold LNG of mistake and the BOG that enter in after-condenser carry out heat exchange, then condensed BOG is passed in the first distributor, simultaneously by with BOG heat exchange after the cold LNG of mistake pass in the first distributor, the two is mixed, then is conveyed in LNG storage tank by throttle valve;The another part distributing by the second distributor is crossed cold LNG and is passed in the 3rd distributor, and the 3rd distributor is divided into two-way, is delivered directly in filling machine.
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Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
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CN104964161A (en) * | 2015-07-17 | 2015-10-07 | 中海石油气电集团有限责任公司 | BOG (boil off gas) recovery processing method and system for LNG (liquid natural gas) receiving terminal |
CN105371103A (en) * | 2015-10-02 | 2016-03-02 | 常州大学 | Combined type natural gas recovery system and method |
CN105444523A (en) * | 2015-10-23 | 2016-03-30 | 中国空分设备有限公司 | Reliquefaction system and technique for compressing expanded liquified BOG through BOG |
CN105627694A (en) * | 2016-03-14 | 2016-06-01 | 江苏德邦工程有限公司 | System and method for compression, liquefaction and recovery of BOG in LNG filling station |
CN105953072A (en) * | 2016-06-30 | 2016-09-21 | 日照海达尔加气设备有限公司 | Gas dispenser for injecting liquefied natural gas while gas is mixed in |
CN106122756A (en) * | 2016-08-16 | 2016-11-16 | 中科赛德(北京)科技有限公司 | A kind of liquefied natural gas tank car reclaiming BOG |
CN106287221A (en) * | 2015-06-02 | 2017-01-04 | 中国石油化工股份有限公司 | A kind of liquefied natural gas receiving station boil-off gas directly exports technique and device |
CN106440655A (en) * | 2016-08-16 | 2017-02-22 | 中科赛德(北京)科技有限公司 | Skid-mounted liquefying device for recycling BOG (Boil of gas) of LNG (liquefied natural gas) tank car |
CN107449220A (en) * | 2017-09-19 | 2017-12-08 | 浙江大学常州工业技术研究院 | The re-liquefied recovery systems of BOG and the re-liquefied recovery process of BOG |
CN107543368A (en) * | 2017-07-21 | 2018-01-05 | 中国科学院理化技术研究所 | A kind of remaining BOG gases recycling system |
CN109253390A (en) * | 2018-11-09 | 2019-01-22 | 西安石油大学 | A kind of BOG recovery and processing system and treatment process |
CN115493081A (en) * | 2022-09-14 | 2022-12-20 | 重庆燃气集团股份有限公司 | Zero release BOG cyclic recycling utilizes system |
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Cited By (16)
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CN106287221A (en) * | 2015-06-02 | 2017-01-04 | 中国石油化工股份有限公司 | A kind of liquefied natural gas receiving station boil-off gas directly exports technique and device |
CN104964161A (en) * | 2015-07-17 | 2015-10-07 | 中海石油气电集团有限责任公司 | BOG (boil off gas) recovery processing method and system for LNG (liquid natural gas) receiving terminal |
CN105371103A (en) * | 2015-10-02 | 2016-03-02 | 常州大学 | Combined type natural gas recovery system and method |
CN105444523A (en) * | 2015-10-23 | 2016-03-30 | 中国空分设备有限公司 | Reliquefaction system and technique for compressing expanded liquified BOG through BOG |
CN105444523B (en) * | 2015-10-23 | 2018-01-05 | 中国空分工程有限公司 | Using BOG itself compression-expansions liquefaction BOG re-liquefied system and technique |
CN105627694A (en) * | 2016-03-14 | 2016-06-01 | 江苏德邦工程有限公司 | System and method for compression, liquefaction and recovery of BOG in LNG filling station |
CN105953072A (en) * | 2016-06-30 | 2016-09-21 | 日照海达尔加气设备有限公司 | Gas dispenser for injecting liquefied natural gas while gas is mixed in |
CN105953072B (en) * | 2016-06-30 | 2018-03-02 | 日照海达尔加气设备有限公司 | A kind of gas mixing fills liquefied natural gas aerating machine |
CN106122756A (en) * | 2016-08-16 | 2016-11-16 | 中科赛德(北京)科技有限公司 | A kind of liquefied natural gas tank car reclaiming BOG |
CN106440655A (en) * | 2016-08-16 | 2017-02-22 | 中科赛德(北京)科技有限公司 | Skid-mounted liquefying device for recycling BOG (Boil of gas) of LNG (liquefied natural gas) tank car |
CN107543368B (en) * | 2017-07-21 | 2019-12-27 | 中国科学院理化技术研究所 | Residual BOG gas recycling system |
CN107543368A (en) * | 2017-07-21 | 2018-01-05 | 中国科学院理化技术研究所 | A kind of remaining BOG gases recycling system |
CN107449220A (en) * | 2017-09-19 | 2017-12-08 | 浙江大学常州工业技术研究院 | The re-liquefied recovery systems of BOG and the re-liquefied recovery process of BOG |
CN109253390B (en) * | 2018-11-09 | 2019-06-11 | 西安石油大学 | A kind of BOG recovery and processing system and treatment process |
CN109253390A (en) * | 2018-11-09 | 2019-01-22 | 西安石油大学 | A kind of BOG recovery and processing system and treatment process |
CN115493081A (en) * | 2022-09-14 | 2022-12-20 | 重庆燃气集团股份有限公司 | Zero release BOG cyclic recycling utilizes system |
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