阅读说明：本技术 一种井口气内二氧化碳回收装置 (Carbon dioxide recovery unit in well head gas ) 是由 周传臣 王晓燕 王志宏 程海鹰 张婧 韩英波 郭立伟 张�杰 庄永涛 苏欣欣 冀 于 2020-11-30 设计创作，主要内容包括：本发明提供一种井口气内二氧化碳回收装置,涉及二氧化碳回收技术领域。该井口气二氧化碳回收装置,包括油气分离器、换热器、胺法吸收塔、铜氨溶液吸收器、干燥床、二氧化碳压缩机、液化器、气液分离罐、燃烧炉。通过对原油与井口气同时抽出可以降低井口气锁的情况,在原油与井口气分离后,井口气经过胺法吸收塔脱去硫化氢,再经过铜氨溶液吸收器除去一氧化碳,之后脱去水分,得到干燥的甲烷、二氧化碳混合气,经过液化得到液体二氧化碳,以便注井再使用,未液化的二氧化碳和甲烷在燃烧炉进行不充分燃烧,得到的燃烧热经过余热锅炉利用,水、一氧化碳和二氧化碳重新进入,参与循环。(The invention provides a device for recovering carbon dioxide in wellhead gas, and relates to the technical field of carbon dioxide recovery. The wellhead gas carbon dioxide recovery device comprises an oil-gas separator, a heat exchanger, an amine absorption tower, a copper ammonia solution absorber, a drying bed, a carbon dioxide compressor, a liquefier, a gas-liquid separation tank and a combustion furnace. The condition of well head airlock can be reduced by simultaneously pumping out crude oil and well head gas, after the crude oil is separated from the well head gas, the well head gas is subjected to hydrogen sulfide removal through an amine absorption tower, carbon monoxide removal through a cuprammonium solution absorber and moisture removal to obtain dry methane and carbon dioxide mixed gas, liquid carbon dioxide is obtained through liquefaction, so that the injection well can be reused, carbon dioxide and methane which are not liquefied are insufficiently combusted in a combustion furnace, the obtained combustion heat is utilized through a waste heat boiler, and water, carbon monoxide and carbon dioxide enter again to participate in circulation.)

1. The utility model provides a carbon dioxide recovery unit in wellhead gas which characterized in that: comprises an oil-gas separator (1), a heat exchanger (2), an amine absorption tower (3), a cuprammonium solution absorber (11), a drying bed (4), a carbon dioxide compressor (5), a liquefier (6), a gas-liquid separation tank (7) and a combustion furnace (12);

an inlet of the oil-gas separator (1) is connected with a pressure reducing valve (9) through a pipeline, an air outlet of the oil-gas separator (1) is connected with a cold side inlet of the heat exchanger (2) through a pipeline, a cold side outlet of the oil-gas separator (1) is connected with an air inlet of the amine method absorption tower (3) through a pipeline, an air outlet of the amine method absorption tower (3) is connected with an air inlet of a copper ammonia solution absorber (11) through a pipeline, an air outlet of the copper ammonia solution absorber (11) is connected with an inlet of the drying bed (4) through a pipeline, an outlet of the drying bed (4) is connected with an air inlet of a carbon dioxide compressor (5) through a pipeline, an air outlet of the carbon dioxide compressor (5) is connected with a hot side inlet of the heat exchanger (2) through a pipeline, and a hot side outlet of the heat exchanger (2) is, the outlet of the liquefier (6) is connected with the inlet of a gas-liquid separation tank (7) through a pipeline, the liquid outlet of the gas-liquid separation tank (7) is connected with a liquid carbon dioxide storage tank (18) through a pipeline, the gas outlet of the gas-liquid separation tank (7) is connected with the gas inlet of a combustion furnace (12) through a pipeline, the gas outlet of the combustion furnace (12) is connected with a waste heat boiler (13) through a pipeline, and the gas outlet of the waste heat boiler (13) is connected with the cold side inlet of the heat exchanger (2) through a pipeline.

2. A device for carbon dioxide recovery in well head gas according to claim 1, characterized in that: the liquid outlet of oil and gas separator (1) bottom has crude oil pump (8) through the pipe connection, the oil-out of crude oil pump (8) has crude oil storage jar (16) through the pipe connection.

3. A device for carbon dioxide recovery in well head gas according to claim 1, characterized in that: the liquid inlet of the amine absorption tower (3) is connected with an amine liquid pump (15) through a pipeline, and the inlet of the amine liquid pump (15) is connected with a diethanolamine aqueous solution storage tank (14) through a pipeline.

4. A device for carbon dioxide recovery in well head gas according to claim 1, characterized in that: the pipeline between the heat exchanger (2) and the waste heat boiler (13) is provided with a one-way valve (10), and the one-way valve (10) is communicated from the waste heat boiler (13) to one side of the heat exchanger (2).

5. A device for carbon dioxide recovery in well head gas according to claim 1, characterized in that: the air inlet of the combustion furnace (12) is connected with an oxygen tank through a pipeline.

6. A device for carbon dioxide recovery in well head gas according to claim 1, characterized in that: the inlet of the pressure reducing valve (9) is connected with an oil pumping well head (17) through a pipeline.

7. A device for carbon dioxide recovery in well head gas according to claim 1, characterized in that: the copper wire content of the copper ammonia solution absorber (11) is not less than four fifths of the capacity of the copper ammonia solution absorber.

8. A device for carbon dioxide recovery in well head gas according to claim 3, characterized in that: and the diethanolamine aqueous solution storage tank (14) is internally provided with 15-20% diethanolamine aqueous solution.

Technical Field

The invention relates to the technical field of carbon dioxide recovery, in particular to a device for recovering carbon dioxide in wellhead gas.

Background

In recent years, with the mature development of carbon dioxide injection well technology, carbon dioxide is widely used in the aspect of injection well.

The oil field can generate a large amount of well head associated gas in the process of exploitation, commonly called well head gas. The main component of the wellhead gas is methane, and in addition, the wellhead gas also contains corrosive and toxic media such as hydrogen sulfide, carbon dioxide, sulfur dioxide and carbon monoxide, and the difference is large. In the past, due to the lagging process level, corrosive and toxic components in well head gas cannot be thoroughly treated, so that the well head gas cannot be recycled and utilized, most of the well head gas is discharged and burnt, a large amount of energy is wasted, and the environment is seriously polluted.

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides a device for recovering carbon dioxide in wellhead gas, which solves the problems that the wellhead gas is directly discharged to sulfuration and carbon monoxide, the physical health of workers is easily harmed, and the carbon dioxide is discharged to cause resource waste.

(II) technical scheme

In order to achieve the purpose, the invention is realized by the following technical scheme: a carbon dioxide recovery device in well head gas comprises an oil-gas separator, a heat exchanger, an amine absorption tower, a cuprammonium solution absorber, a drying bed, a carbon dioxide compressor, a liquefier, a gas-liquid separation tank and a combustion furnace;

the inlet of the oil-gas separator is connected with a pressure reducing valve through a pipeline, the gas outlet of the oil-gas separator is connected with the cold side inlet of a heat exchanger through a pipeline, the cold side outlet of the oil-gas separator is connected with the gas inlet of an amine method absorption tower through a pipeline, the gas outlet of the amine method absorption tower is connected with the gas inlet of a copper ammonia solution absorber through a pipeline, the gas outlet of the copper ammonia solution absorber is connected with the inlet of a drying bed through a pipeline, the outlet of the drying bed is connected with the gas inlet of a carbon dioxide compressor through a pipeline, the gas outlet of the carbon dioxide compressor is connected with the hot side inlet of the heat exchanger through a pipeline, the hot side outlet of the heat exchanger is connected with the inlet of a liquefier through a pipeline, the outlet of the liquefier is connected with the inlet of a gas, the gas outlet of the gas-liquid separation tank is connected with the gas inlet of the combustion furnace through a pipeline, the gas outlet of the combustion furnace is connected with a waste heat boiler through a pipeline, and the gas outlet of the waste heat boiler is connected with the cold side inlet of the heat exchanger through a pipeline.

Preferably, a liquid outlet at the bottom of the oil-gas separator is connected with a crude oil pump through a pipeline, and an oil outlet of the crude oil pump is connected with a crude oil storage tank through a pipeline.

Preferably, the liquid inlet of the amine absorption tower is connected with an amine liquid pump through a pipeline, and the inlet of the amine liquid pump is connected with a diethanolamine aqueous solution storage tank through a pipeline.

Preferably, a one-way valve is arranged on a pipeline between the heat exchanger and the waste heat boiler, and the one-way valve is communicated from the waste heat boiler to one side of the heat exchanger.

Preferably, the air inlet of the combustion furnace is connected with an oxygen tank through a pipeline.

Preferably, the inlet of the pressure reducing valve is connected with an oil pumping wellhead through a pipeline.

Preferably, the copper wire content of the copper ammonia solution absorber is not less than four fifths of the capacity of the copper ammonia solution absorber.

Preferably, the diethanolamine aqueous solution storage tank is 15-20% diethanolamine aqueous solution.

The working principle is as follows: pumping wellhead gas and crude oil into the wellhead gas carbon dioxide recovery device through pumping equipment, firstly, reducing the pressure to 0.2-0.4 MPa through a pressure reducing valve, then entering an oil-gas separator, separating the crude oil from the wellhead gas through the action of the oil-gas separator, enabling the crude oil to enter a crude oil storage tank from the bottom of the oil-gas separator through the action of a crude oil pump, enabling low-temperature wellhead gas to enter a heat exchanger from the top of the oil-gas separator, performing heat exchange with high-temperature compressed wellhead gas from the outlet of a carbon dioxide compressor, further increasing the temperature to above 10 ℃, then absorbing and taking hydrogen sulfide through an amine absorption tower, enriching the absorbed hydrogen sulfide, heating to 100-130 ℃, cooling to obtain high-concentration hydrogen sulfide, removing the hydrogen sulfide, then entering a copper ammonia solution absorber to remove carbon monoxide, then pressurizing to 2.2MPa through the carbon dioxide compressor, enabling the temperature to reach 50 ℃, the pressurized well gas enters the heat exchanger again to exchange heat with low-temperature well gas from the oil-gas separator, the temperature is reduced to below 20 ℃, the cooled compressed well gas enters the liquefier to be continuously cooled to-24 ℃, so that carbon dioxide gas in the well gas is liquefied, the cooled well gas enters the gas-liquid separation tank, a small amount of carbon dioxide which is not liquefied and methane enter the combustion furnace, insufficient oxygen is provided through the oxygen tank to be combusted to obtain water, carbon monoxide and carbon dioxide, the temperature is reduced after waste heat utilization of the waste heat boiler, then the liquefied carbon dioxide enters the liquid carbon dioxide storage tank from a cold side inlet of the heat exchanger through the one-way valve to participate in circulation treatment, and the liquefied carbon dioxide enters the liquid carbon dioxide storage tank from a liquid outlet of the gas-liquid separation.

(III) advantageous effects

The invention provides a device for recovering carbon dioxide in well head gas. The method has the following beneficial effects:

1. according to the invention, the condition of wellhead gas lock can be reduced by simultaneously pumping out crude oil and wellhead gas, after the crude oil and wellhead gas are separated, the wellhead gas is subjected to hydrogen sulfide removal through an amine absorption tower, carbon monoxide removal through a cuprammonium solution absorber, moisture removal to obtain dry methane-carbon dioxide mixed gas, and liquefaction to obtain liquid carbon dioxide for well injection and reuse.

2. According to the invention, a small amount of unliquefied carbon dioxide and methane separated by the liquefier are combusted by providing the combustion furnace with insufficient oxygen for combustion, so that direct discharge of the carbon dioxide and methane is avoided, the combustion heat is utilized by the waste heat boiler, and water, carbon monoxide and carbon dioxide enter again to participate in circulation.

Drawings

Fig. 1 is a schematic diagram of the principle of the present invention.

Wherein, 1, an oil-gas separator; 2. a heat exchanger; 3. an amine process absorber; 4. drying the bed; 5. a carbon dioxide compressor; 6. a liquefier; 7. a gas-liquid separation tank; 8. a crude oil pump; 9. a pressure reducing valve; 10. a one-way valve; 11. a copper ammonia solution absorber; 12. a combustion furnace; 13. a waste heat boiler; 14. a diethanolamine aqueous solution storage tank; 15. an amine liquid pump; 16. a crude oil storage tank; 17. pumping the oil well head; 18. a liquid carbon dioxide storage tank.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example (b):

as shown in fig. 1, an embodiment of the present invention provides a recovery device for carbon dioxide in well head gas, including an oil-gas separator 1, a heat exchanger 2, an amine method absorption tower 3, a cuprammonia solution absorber 11, a drying bed 4, a carbon dioxide compressor 5, a liquefier 6, a gas-liquid separation tank 7, and a combustion furnace 12;

an inlet of the oil-gas separator 1 is connected with an air outlet of a pressure reducing valve 9 through a pipeline, the air outlet of the oil-gas separator 1 is connected with a cold side inlet of a heat exchanger 2 through a pipeline, the heat exchanger 2 is used for exchanging heat between cold well head gas and mixed gas of carbon dioxide and methane which are compressed and heated, an inlet of the pressure reducing valve 9 is connected with an oil pumping well head 17 through a pipeline, a cold side outlet of the oil-gas separator 1 is connected with an air inlet of an amine method absorption tower 3 through a pipeline, the amine method absorption tower 3 absorbs hydrogen sulfide through a 15-20% diethanolamine aqueous solution provided in a diethanolamine aqueous solution storage tank 14 by using an amine method process, the absorbed hydrogen sulfide is heated to 100-130 ℃ after being enriched, and is cooled to obtain high-concentration hydrogen sulfide, and then can be used for producing sulfur, a liquid inlet of the amine method absorption tower 3 is connected with an amine, the diethanolamine aqueous solution storage tank 14 is a 15-20% diethanolamine aqueous solution, the air outlet of the amine absorption tower 3 is connected with the air inlet of a copper ammonia solution absorber 11 through a pipeline, the copper wire content of the copper ammonia solution absorber 11 is not less than four fifths of the capacity of the copper ammonia solution absorber 11, when the copper ammonia solution is in yellow-green precipitation, two thirds of old solution is poured, then new absorption liquid is added into the old solution, the air outlet of the copper ammonia solution absorber 11 is connected with the inlet of a drying bed 4 through a pipeline, the drying bed 4 is used for dewatering, the existing dewatering drying bed is not limited, the outlet of the drying bed 4 is connected with the air inlet of a carbon dioxide compressor 5 through a pipeline, the air outlet of the carbon dioxide compressor 5 is connected with the hot side inlet of a heat exchanger 2 through a pipeline, the hot side outlet of the heat exchanger 2 is connected with the inlet of a liquefie, the outlet of the liquefier 6 is connected with the inlet of the gas-liquid separation tank 7 through a pipeline, the liquid outlet of the gas-liquid separation tank 7 is connected with a liquid carbon dioxide storage tank 18 through a pipeline, the gas outlet of the gas-liquid separation tank 7 is connected with the gas inlet of the combustion furnace 12 through a pipeline, the gas inlet of the combustion furnace 12 is connected with an oxygen tank through a pipeline, the methane in the combustion furnace 12 is flame-retardant only through oxygen, and insufficient combustion is performed, so that new gas cannot be introduced into the wellhead gas carbon dioxide recovery device, the exhaust port of the combustion furnace 12 is connected with a waste heat boiler 13 through a pipeline, the exhaust port of the waste heat boiler 13 is connected with the cold side inlet of the heat exchanger 2 through a pipeline, a check valve 10 is arranged on the pipeline between the heat exchanger 2 and the waste heat boiler 13, wellhead gas is prevented from entering the combustion furnace 12, and the check valve 10 is communicated from the waste heat boiler 13 to one side of the heat exchanger 2.

A liquid outlet at the bottom of the oil-gas separator 1 is connected with a crude oil pump 8 through a pipeline, and an oil outlet of the crude oil pump 8 is connected with a crude oil storage tank 16 through a pipeline.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.