Utility model content
The purpose of this utility model is to provide one to produce liquefied natural gas plant, can improve system energy efficiency, reduces investment outlay, increase the benefit.
For achieving the above object, embodiment of the present utility model adopts following technical scheme:
One produces liquefied natural gas plant, comprises ice chest, the abundant heat exchange of methane that liquid oxygen and coal gasifying process produce in described ice chest.
Boil-off gas in liquefied natural gas flash tank and LNG tank all flows out from tank deck, flows into ice chest, is warming up to normal temperature after the methane heat exchange produced with coal gasifying process, then flows into and regenerate heating furnace using as fuel gas.
Gasification furnace produce raw coke oven gas in high-temperature heat-exchanging with the heat exchange of methane purifying device regenerating molecular sieve gas.
Described methane purifying device regenerating molecular sieve gas bag draws together a part for the methane gas from methane purifying device.
Also comprise air compressor, space division system, low temperature heat exchanger, the air flowed out from air compressor enters described low temperature heat exchanger and cryogenic oxygen heat exchange.
Be warming up to the oxygen after normal temperature fully mix with the carbon dioxide produced from gas cleaning device after together with enter gasification furnace.
What the utility model embodiment provided produces liquefied natural gas plant, utilize the cold energy that liquid oxygen gasification process produces, it is LNG that simple employing ice chest, liquid oxygen storage tank, LNG flash tank etc. can realize Coal Gasification synthetic product methane direct liquefaction, and flow process is simple, remarkable benefit.
Detailed description of the invention
Produce liquefied natural gas plant below in conjunction with accompanying drawing to the utility model embodiment to be described in detail.
What the utility model provided produces liquefied natural gas plant, comprises ice chest, the abundant heat exchange of methane that liquid oxygen and coal gasifying process produce in described ice chest.
What the utility model embodiment provided produces liquefied natural gas plant, utilize the cold energy that liquid oxygen gasification process produces, it is LNG that simple employing ice chest, liquid oxygen storage tank, LNG flash tank etc. can realize Coal Gasification synthetic product methane direct liquefaction, and flow process is simple, remarkable benefit.Oxygen-rich gasification technique in coal gasification processes needs a large amount of oxygen of continuous continual use, and liquid oxygen is converted into oxygen by vaporizer, and a large amount of cold energy of gasification is wasted.This technique reclaims liquid oxygen cold energy by ice chest, and the methane direct liquefaction synthesized by Coal Gasification is LNG.This technique is killed two birds with one stone, not only make liquid oxygen gasification be the oxygen-rich gasification needs that oxygen meets gasification furnace, reclaimed the high-grade cold energy in liquid oxygen simultaneously in the process, utilized this part cold energy by methane direct liquefaction, provide cost savings, run simple, by calculating, the liquid oxygen cold that oxygen-rich gasification consumes, often consume 1 side's oxygen, Coal Gasification can produce 0.7 side's methane, and liquid oxygen cold energy can produce 0.88 side LNG after reclaiming, and meets methane liquefaction chilling requirement far away.This technological process is simple, small investment benefit is obvious, tradition LNG liquefaction process needs to adopt compressor, decompressor, the equipment such as cold-producing medium storage tank usually, investment is large, run complicated, and this technological process just can realize LNG liquefaction by means of only ice chest heat exchange, therefore this technique effectively saves the investment that traditional LNG liquefies, earning rate significantly improves, and economic benefit is obvious.
Embodiment one
As shown in Figure 1, divide from sky or the liquid oxygen of outsourcing flows out through liquid oxygen storage tank 1 time drain pipe, boil-off gas is flowed out by liquid oxygen storage tank 1 top, enters ice chest 2, the abundant heat exchange with methane in ice chest 2, flow out ice chest after liquid oxygen gasification being warming up to normal temperature, enter gasifying agent mixing arrangement 6, together with after fully mixing with the gasifying agent such as air or carbon dioxide, enter gasification furnace 7, react with coal in gasification furnace 7, carbon monoxide, carbon dioxide are rich in generation, methane, the raw coke oven gas of the components such as hydrogen.
From the raw gas temperature of gasification furnace 7 at 100 ~ 150 DEG C, with the methane from methane purifying device 11 in high-temperature heat-exchanging 8 after heat exchange temperature be reduced to 70 ~ 100 DEG C and enter gas cleaning device 9, raw coke oven gas enters methanation reaction stove 10 after purification, more than 99% is reached from methanation reaction stove 10 gas component methane content out, again after methane purifying device 11 dewaters demercuration, gas meets liquefaction duty requirements completely, normal temperature methane gas enters ice chest 2, after the abundant heat exchange of liquid oxygen, methane temperature is reduced to-150 ~-160 DEG C, liquefaction is for flowing into LNG flash tank 3 after LNG, the LNG pressure entering flash tank may reduce, and a transient evaporation evaporation part, in order to gas-liquid separation obtains qualified LNG, arrange flash tank to be necessary, also play the effect of pressure buffer simultaneously.LNG flows in LNG storage tank 4 through LNG flash tank 3 times drain pipes, and LNG can transport in entrucking.
From in the methane gas of methane purifying device 11 about 10% ~ 15% gas through high-temperature heat-exchanging 8, regeneration heating furnace 5 is flowed into after being warming up to 90 ~ 140 DEG C, again methane purifying device 11 is flowed into after being heated to 280 ~ 320 DEG C, as purifier regenerating molecular sieve gas, the raw coke oven gas that gasification furnace is produced and the heat exchange of methane purifying device regenerating molecular sieve gas, reclaim raw coke oven gas waste heat to the preheating of regenerating molecular sieve gas, fuel saving cost.After regenerated, gas flows into methanation reaction stove 10 as fuel gas.
Boil-off gas wherein in LNG flash tank 3 and LNG storage tank 4 all flows out from tank top, flows into after being warming up to normal temperature in ice chest 2, flows into regeneration heating furnace 5 as fuel gas.LNG flash steam is recycled, by regeneration heating furnace, regenerating molecular sieve gas is heated, effective fuel saving cost, remarkable benefit.
Embodiment two
As shown in Figure 2, first the air in air is forced into about 0.4MPa by air compressor 12, enters low temperature heat exchanger 13 and-40 ~-50 DEG C of cryogenic oxygen heat exchange.In heat exchanger after precooling, normal temperature air temperature is reduced to 10 ~ 20 DEG C, enters space division system 14, air is separated liquefaction under the low temperature of-180 ~-170 DEG C, obtains liquid oxygen, liquid oxygen flows into liquid oxygen storage tank 1 and stores.Liquid oxygen flows out through liquid oxygen storage tank 1 time drain pipe, liquid oxygen boil-off gas is flowed out by liquid oxygen storage tank 1 top, flow into ice chest 2, the abundant heat exchange with methane in ice chest 2, flow out ice chest after liquid oxygen gasification being warming up to-40 ~-50 DEG C and enter low temperature heat exchanger 13, be warming up to normal temperature with air heat-exchange, this low temperature heat exchanger 13, by compressed air and cryogenic oxygen heat exchange, reduces compressed-air actuated temperature and improves the temperature of cryogenic oxygen.Enter gasifying agent mixing arrangement 6, enter gasification furnace 7 together with after fully mixing with the carbon dioxide produced from gas cleaning device 9 decarbonizing section, react with coal in gasification furnace 7, produce and be rich in carbon monoxide, carbon dioxide, methane, the raw coke oven gas of the components such as hydrogen.
From the raw gas temperature of gasification furnace 7 at 100 ~ 150 DEG C, with the methane from methane purifying device 11 in high temperature heat exchanger 8 after heat exchange temperature be reduced to 70 ~ 100 DEG C and enter gas cleaning device 9, raw coke oven gas enters methanation reaction stove 10 after purification, more than 99% is reached from methanation reaction stove 10 gas component methane content out, again after methane purifying device 11 dewaters demercuration, gas meets liquefaction duty requirements completely, normal temperature methane gas enters ice chest 2, after the abundant heat exchange of liquid oxygen, methane temperature is reduced to-150 ~-160 DEG C, liquefaction is for flowing into LNG flash tank 3 after LNG, LNG flows in LNG storage tank 4 through LNG flash tank 3 times drain pipes, LNG can transport in entrucking.
From in the methane gas of methane purifying device 11 about 10% ~ 15% gas through high-temperature heat-exchanging 11, regeneration heating furnace 5 is flowed into after being warming up to 90 ~ 140 DEG C, again methane purifying device 11 is flowed into after being heated to 280 ~ 320 DEG C, as purifier regenerating molecular sieve gas, the raw coke oven gas that gasification furnace is produced and the heat exchange of methane purifying device regenerating molecular sieve gas, reclaim raw coke oven gas waste heat to the preheating of regenerating molecular sieve gas, fuel saving cost.After regenerated, gas flows into methanation reaction stove 10 as fuel gas.
Boil-off gas wherein in LNG flash tank 3 and LNG storage tank 4 all flows out from tank top, flows into after being warming up to normal temperature in ice chest 2, flows into regeneration heating furnace 5 as fuel gas.LNG flash steam is recycled, by regeneration heating furnace, regenerating molecular sieve gas is heated, effective fuel saving cost, remarkable benefit.
The above; be only detailed description of the invention of the present utility model; but protection domain of the present utility model is not limited thereto; anyly be familiar with those skilled in the art in the technical scope that the utility model discloses; change can be expected easily or replace, all should be encompassed within protection domain of the present utility model.Therefore, protection domain of the present utility model should be as the criterion with the protection domain of described claim.