CN103603638B - A kind of gas hydrates CO in conjunction with voltage drop method2Replacement exploitation method - Google Patents
A kind of gas hydrates CO in conjunction with voltage drop method2Replacement exploitation method Download PDFInfo
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- CN103603638B CN103603638B CN201310574236.1A CN201310574236A CN103603638B CN 103603638 B CN103603638 B CN 103603638B CN 201310574236 A CN201310574236 A CN 201310574236A CN 103603638 B CN103603638 B CN 103603638B
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- emulsion
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- gas hydrates
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- 150000004677 hydrates Chemical class 0.000 title claims abstract description 36
- 238000000034 method Methods 0.000 title claims abstract description 34
- 239000007789 gas Substances 0.000 claims abstract description 49
- 229910002092 carbon dioxide Inorganic materials 0.000 claims abstract description 44
- 239000000839 emulsion Substances 0.000 claims abstract description 33
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims abstract description 16
- 230000036772 blood pressure Effects 0.000 claims abstract description 11
- VTVVPPOHYJJIJR-UHFFFAOYSA-N carbon dioxide;hydrate Chemical compound O.O=C=O VTVVPPOHYJJIJR-UHFFFAOYSA-N 0.000 claims abstract description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 8
- 238000000354 decomposition reaction Methods 0.000 claims abstract description 7
- 239000003345 natural gas Substances 0.000 claims abstract description 7
- 238000005553 drilling Methods 0.000 claims abstract description 6
- 238000002347 injection Methods 0.000 claims abstract description 6
- 239000007924 injection Substances 0.000 claims abstract description 6
- 239000007788 liquid Substances 0.000 claims abstract description 5
- 239000002002 slurry Substances 0.000 claims abstract description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 4
- 239000006185 dispersion Substances 0.000 claims abstract description 4
- 239000003995 emulsifying agent Substances 0.000 claims abstract description 4
- 230000001737 promoting effect Effects 0.000 claims abstract description 4
- 238000009792 diffusion process Methods 0.000 claims description 7
- 239000011148 porous material Substances 0.000 claims description 6
- 238000006073 displacement reaction Methods 0.000 claims description 4
- 238000003860 storage Methods 0.000 claims description 4
- 230000035699 permeability Effects 0.000 claims description 3
- 238000007599 discharging Methods 0.000 abstract 1
- NMJORVOYSJLJGU-UHFFFAOYSA-N methane clathrate Chemical compound C.C.C.C.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O NMJORVOYSJLJGU-UHFFFAOYSA-N 0.000 description 7
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 6
- 238000011084 recovery Methods 0.000 description 5
- 239000001569 carbon dioxide Substances 0.000 description 3
- 238000005065 mining Methods 0.000 description 3
- 230000006837 decompression Effects 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- 238000011549 displacement method Methods 0.000 description 2
- 238000010494 dissociation reaction Methods 0.000 description 2
- 230000005593 dissociations Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000005431 greenhouse gas Substances 0.000 description 2
- 238000003892 spreading Methods 0.000 description 2
- 238000013019 agitation Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000003112 inhibitor Substances 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- 238000001330 spinodal decomposition reaction Methods 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B41/00—Equipment or details not covered by groups E21B15/00 - E21B40/00
- E21B41/0099—Equipment or details not covered by groups E21B15/00 - E21B40/00 specially adapted for drilling for or production of natural hydrate or clathrate gas reservoirs; Drilling through or monitoring of formations containing gas hydrates or clathrates
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- Geology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- Physics & Mathematics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Physical Or Chemical Processes And Apparatus (AREA)
- Gas Separation By Absorption (AREA)
- Carbon And Carbon Compounds (AREA)
- Medical Preparation Storing Or Oral Administration Devices (AREA)
Abstract
A kind of gas hydrates CO in conjunction with voltage drop method2Replacement exploitation method, first adopts low density slurries drilling well to gas hydrates reservoir blood pressure lowering, makes portion of natural gas decomposition of hydrate;Then controlling pressure in high-pressure bottle selects isomery alcohol ethoxylate to be emulsifying agent with temperature, with liquid CO2It is continuous media for dispersion phase water, prepares CO2Emulsion;Again through drilling through CO2Emulsion injection channel, by CO2Gas hydrates reservoir is injected from emulsion inlet with the emulsion of water;Control reservoir pressure by emulsion inlet, control its pressure corresponding to, within the scope of the carbon dioxide hydrate vapor pressure of reservoir temperature, promoting CO2React with gas hydrates, generate carbon dioxide hydrate and CH4Gas。The present invention realizes CO2Reduce discharging, improve the safety of exploitation, Reservoir Seepage characteristic can be effectively improved, promote that emulsion is fully infiltrated into reservoir, improve CO2The efficiency of replacement exploitation method。
Description
Technical field
The invention belongs to technical field of petroleum extraction, relate to a kind of based on CO2The recovery method of the gas hydrates of displacement method。
Background technology
Along with the reserves of traditional fossil energy sharply reduce, the utilization of new forms of energy is given special attention with development by countries in the world。Wherein, gas hydrates, as a kind of new and effective, energy that reserves are big, are generally believed have wide DEVELOPMENT PROSPECT by the world。And the state such as the U.S., Japan has all found in respective marine site and has produced gas hydrates。Gas hydrate mining methods traditional at present mainly has heat shock method, voltage drop method, inhibitor method etc.。But it is in experimentation and examination mining phase。
Voltage drop method is a kind of recovery method promoting gas hydrate dissociation by reducing pressure。Decompression approach mainly has two kinds: 1) adopt low density slurries drilling well to reach decompression purpose;2) by pumping free gas below gas hydrates layer or other fluids reduce the pressure of gas hydrates layer。Blood pressure lowering recovery method does not need continuous agitation, less costly。But methane gas is as a kind of important greenhouse gases, the extensive spinodal decomposition of hydrate that in recovery process, any factor is brought out, all it would be possible to bring heavy damage to global climate environment, and gas hydrate dissociation will make deposition layer intensity reduce, likely cause geologic structure unstability, cause serious geological disaster, destroy periphery ecological environment。
CO2Replacement exploitation method is in the recent period relatively popular object of study, and it is according to the pressure condition of to be natural gas be hydrate zone。When uniform temperature, the pressure ratio carbon dioxide hydrate that gas hydrates remain stable for needing is higher。Therefore in a certain specific pressure limit, gas hydrates can decompose, and carbon dioxide hydrate is then easily formed and remains stable for。But the decomposition reaction of the heat gas hydrates of this effect release is continued for down。
CO2The research of displacement method exploitation of gas hydrate has very important significance。On the one hand, in air or commercial production produce carbon dioxide be injected in gas hydrates reservoir, it is possible to carbon dioxide is stored in seabed with the form of hydrate, so can effectively slow down the greenhouse effect of carbon dioxide;On the other hand, CO2Displacement CH4Process can intactly preserve hydrate deposit, it is to avoid the marine geologic disasters caused because of the exploitation of hydrate。
CO in deposition layer2The process of displacer gas hydrate is subject to CO2At the material impact containing the diffusion in hydrate deposit。Use gaseous state or liquid CO2Displacer gas hydrate, the CO that replacement process ectomesoderm firstly generates2Hydrate will play shielding action, hinder CO2Spreading mutually to containing hydrate, cause replacement process slow, replacement rate increases over time and generates CO2The rapid development of hydrate layer thickness reduces。CO2Emulsion can strengthen molecule diffusion and the conduction of heat in replacement process, strengthens replacement process, improves replacement rate。Yet with the existence of gas hydrates, the Penetration Signature of reservoir porous is to CO2The injection of emulsion has a significant impact。In porous media, the decomposed of gas hydrates contributes to opening pore channel, promotes CO2The diffusion of emulsion。
Summary of the invention
The present invention is directed to the deficiency of prior art, according to blood pressure lowering exploitation side CO2The feature of replacement exploitation method and principle, it is proposed to a kind of gas hydrates CO in conjunction with voltage drop method2Replacement exploitation method。Portion of natural gas decomposition of hydrate is made to generate CH by first blood pressure lowering4, open pore channel, promote CO2Emulsion diffusion in reservoir。This method is easily achieved, it is adaptable to gas hydrates CO2The follow-up study of replacement exploitation method。
For reaching with above-mentioned purpose, the present invention adopts following technical proposals:
A kind of gas hydrates CO in conjunction with voltage drop method2Replacement exploitation method, comprises the following steps:
(1) choose blood pressure lowering mouth position, adopt low density slurries drilling well to gas hydrates reservoir blood pressure lowering, make portion of natural gas decomposition of hydrate, open pore channel, improve permeability, promote CO2Emulsion diffusion in reservoir;
(2) CO is produced2Emulsion, controls pressure in high-pressure bottle and selects isomery alcohol ethoxylate (TMN-6) to be emulsifying agent with temperature, with liquid CO2It is continuous media for dispersion phase water, prepares CO2Emulsion;
(3) CO is drilled through2Emulsion injection channel, by CO2Gas hydrates reservoir is injected from emulsion inlet with the emulsion of water;
(4) control reservoir pressure by emulsion inlet, control its pressure corresponding to, within the scope of the carbon dioxide hydrate vapor pressure of reservoir temperature, promoting CO2With gas hydrates generation displacement reaction, generation carbon dioxide hydrate and CH4Gas;
(5) CH is collected at gas discharge outlet4Gas, carries out CH4The storage of gas and transport。
The present invention is applied in gas hydrate mining methods research process, it is adaptable to gas hydrates CO2The follow-up study of replacement exploitation method。
(1) in conjunction with gas hydrates blood pressure lowering recovery method, promote portion of natural gas decomposition of hydrate, open pore channel, promote CO2Spreading in reservoir of emulsion, improves reaction efficiency;
(2) for long-term storage CO2Greenhouse gases provide a kind of important aspect, and frozen soil region and abyssalbenthic geologic structure, ecological environment simultaneously for maintaining containing hydrate deposit stably have great significance。
Accompanying drawing explanation
Accompanying drawing is the gas hydrates CO of the present invention2Replacement exploitation method schematic diagram
Specific embodiment
Embodiments of the invention are described in detail below in conjunction with technical scheme and accompanying drawing。
Embodiment
In the middle part of reservoir, choose 2 blood pressure lowering mouths, adopt low density slurries drilling well to gas hydrates reservoir blood pressure lowering, as shown in drawings, make portion of natural gas decomposition of hydrate, open pore channel, improve permeability, improve Reservoir Seepage characteristic and promote CO2Emulsion diffusion in reservoir;
Produce CO2Emulsion, controls pressure in high-pressure bottle and selects isomery alcohol ethoxylate (TMN-6) to be emulsifying agent with temperature, with liquid CO2It is continuous media for dispersion phase water, prepares CO2Emulsion。Herein, by water and CO2CO is produced under the pressure condition of 30Mpa, the temperature conditions of 0-5 DEG C and the speed of agitator of 3500r/min2Emulsion;
3 CO are drilled through in the two ends of reservoir and centre position2The injection channel of emulsion, by CO2Inject gas hydrates reservoir with the emulsion of water at emulsion inlet, control injection pressure within the scope of 5-8Mpa, see Fig. 1;
Control reservoir pressure by emulsion inlet, control its pressure corresponding within the scope of the carbon dioxide hydrate vapor pressure of reservoir temperature, herein by Stress control at 3-5Mpa, promote CO2With gas hydrates generation displacement reaction, generation carbon dioxide hydrate and CH4Gas;
CH is collected at 2 gas discharge outlets4Gas, is shown in shown in accompanying drawing, carries out CH4The storage of gas and transport。
Above example is the one of the specific embodiment of the invention, and the usual variations and alternatives that those skilled in the art carry out within the scope of the technical program should be included in protection scope of the present invention。
Claims (1)
1. the gas hydrates CO in conjunction with voltage drop method2Replacement exploitation method, its feature comprises the following steps:
(1) choose blood pressure lowering mouth position, adopt low density slurries drilling well to gas hydrates reservoir blood pressure lowering, make portion of natural gas decomposition of hydrate, open pore channel, improve permeability, promote CO2Emulsion diffusion in gas hydrates reservoir;
(2) CO is produced2Emulsion, controls pressure in high-pressure bottle and selects isomery alcohol ethoxylate to be emulsifying agent with temperature, with liquid CO2It is continuous media for dispersion phase water, under the mixing speed of 3500r/min, prepares CO2Emulsion;
(3) CO is drilled through2Emulsion injection channel, by CO2Emulsion injects gas hydrates reservoir from emulsion inlet;
(4) control gas hydrates reservoir pressure by emulsion inlet, control its pressure corresponding to, within the scope of the carbon dioxide hydrate vapor pressure of gas hydrates reservoir temperature, promoting CO2With gas hydrates generation displacement reaction, generation carbon dioxide hydrate and CH4Gas;Collect CH4Gas, carries out CH4The storage of gas and transport。
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CN201310574236.1A CN103603638B (en) | 2013-11-13 | 2013-11-13 | A kind of gas hydrates CO in conjunction with voltage drop method2Replacement exploitation method |
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CN103603638A CN103603638A (en) | 2014-02-26 |
CN103603638B true CN103603638B (en) | 2016-06-22 |
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CN104632163A (en) * | 2015-01-20 | 2015-05-20 | 辽宁石油化工大学 | Natural gas hydrate mining method capable of preventing accidents such as blowout, mine collapse and subsidence |
CN105422056A (en) * | 2016-01-26 | 2016-03-23 | 辽宁石油化工大学 | Method for mining natural gas hydrate in deep seafloor through carbon dioxide method |
CN105971581A (en) * | 2016-06-30 | 2016-09-28 | 华南理工大学 | Device and method for efficiently exploiting natural gas hydrate by adopting flue gas of power plant |
CN106321027A (en) * | 2016-10-21 | 2017-01-11 | 大连理工大学 | Efficient and low-consumption method for exploiting natural gas hydrate of sea bed |
CN106351615B (en) * | 2016-10-31 | 2019-07-19 | 重庆大学 | Halogen family acid solution and solvable carbonate reaction assist hydrate recovery method |
CN107740686A (en) * | 2017-10-23 | 2018-02-27 | 大庆东油睿佳石油科技有限公司 | A kind of method that parallel water horizontal well mixed phase drives exploitation of gas hydrate |
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CN107575196A (en) * | 2017-10-23 | 2018-01-12 | 大庆东油睿佳石油科技有限公司 | A kind of method that gas hydrates row's formula horizontal well mixed phase drives exploitation |
CN107676062A (en) * | 2017-10-23 | 2018-02-09 | 大庆东油睿佳石油科技有限公司 | A kind of method that row's formula horizontal well mixed phase drives exploitation of gas hydrate |
CN108086959B (en) * | 2017-12-12 | 2020-04-24 | 大连理工大学 | Ocean natural gas hydrate exploitation method by water flow erosion method |
CN108086961A (en) * | 2017-12-12 | 2018-05-29 | 大连理工大学 | A kind of water erosion method exploiting ocean natural gas hydrates method of combination heat injection |
CN111271033B (en) * | 2018-12-04 | 2021-04-27 | 中国石油大学(北京) | CO2Emulsion and method for improving and exploiting natural gas hydrate reservoir by injecting emulsion |
CN109736752A (en) * | 2019-01-21 | 2019-05-10 | 燕山大学 | A kind of voltage drop method auxiliary temperature control CO2The recovery method of displacer gas hydrate |
CN109915094A (en) * | 2019-03-29 | 2019-06-21 | 大连理工大学 | A kind of gas hydrates replacement exploitation method of combination carbon dioxide inhibitor |
CN112127850B (en) * | 2019-06-24 | 2021-12-17 | 南京延长反应技术研究院有限公司 | Green process for exploiting combustible ice |
CN111255419B (en) * | 2020-01-19 | 2022-05-17 | 中国海洋石油集团有限公司 | Compound exploitation method of natural gas hydrate |
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