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CN-121991672-A - Rhamnolipid composite oil displacement agent and preparation method and application thereof

CN121991672ACN 121991672 ACN121991672 ACN 121991672ACN-121991672-A

Abstract

The invention discloses a rhamnolipid composite oil displacement agent, a preparation method and application thereof, and relates to the technical field of oilfield oil extraction agents. The main active components of the compound oil displacement agent are rhamnolipid produced by fermenting pseudomonas aeruginosa CCTCC NO. M2025023, and the compound oil displacement agent also comprises cocofatty acid diacetyl amide, sodium dodecyl benzene sulfonate, sodium cocoyl glycinate, cocodimethyl betaine and oleamide propyl betaine. The invention also provides a preparation method of the rhamnolipid composite oil displacement agent, which comprises the following steps of (1) fermenting strains to produce rhamnolipid, (2) preparing rhamnolipid fermentation supernatant or extracting rhamnolipid products, (3) adding 5 additives into the rhamnolipid fermentation supernatant or adding the rhamnolipid extract and 5 additives into water to prepare the rhamnolipid composite oil displacement agent. The rhamnolipid composite oil displacement agent is simple and convenient to prepare, economical and environment-friendly, high in oil displacement activity and applicable to improving the petroleum recovery ratio.

Inventors

  • SU DONGLIANG
  • CHEN GUANG
  • Gong Qiuyu
  • TONY DAVID JAMES
  • AN SHI
  • MA HONGXUE
  • CHEN BINGZHU

Assignees

  • 伊明泰(山东)生物科技有限公司
  • 济南佰赛菲生物科技有限公司

Dates

Publication Date
20260508
Application Date
20260119

Claims (9)

  1. 1. A rhamnolipid composite oil displacement agent is characterized in that the main active ingredient of the composite oil displacement agent is rhamnolipid, wherein the concentration of the rhamnolipid is more than or equal to 0.02wt%. The rhamnolipid is produced by fermenting pseudomonas aeruginosa (Pseudomonas aeruginosa) with the preservation number of CCTCC No. M2025023, wherein the disaccharide double lipid accounts for 63%, the monosaccharide double lipid accounts for 27%, and the total of the monosaccharide single lipid and the disaccharide single lipid accounts for 10%. The rhamnolipid composite oil displacement agent also comprises 5 additives, namely coco fatty acid diacetyl amide (CDEA 1:2), sodium Dodecyl Benzene Sulfonate (SDBS), sodium cocoyl Glycinate (GCS), coco dimethyl betaine (BS-814) and oleamide propyl betaine (OAB).
  2. 2. The rhamnolipid composite oil displacement agent according to claim 1, wherein the composite oil displacement agent is in a liquid form, and the pH value of the solution is 7.0-9.5.
  3. 3. The rhamnolipid composite oil displacement agent of claim 1-2, wherein the composite oil displacement agent is a liquid obtained by adding coco fatty acid diacetyl amide (CDEA 1:2), sodium Dodecyl Benzene Sulfonate (SDBS), sodium cocoyl Glycinate (GCS), coco dimethyl betaine (BS-814) and oleamide propyl betaine (OAB) to fermentation supernatant of rhamnolipid producing strain, or a liquid obtained by adding rhamnolipid, coco fatty acid diacetyl amide (CDEA 1:2), sodium Dodecyl Benzene Sulfonate (SDBS), sodium cocoyl Glycinate (GCS), coco dimethyl betaine (BS-814) and oleamide propyl betaine (OAB) to water, or a dilution of the above liquid.
  4. 4. The rhamnolipid composite oil displacement agent according to claim 1, wherein the final concentration of rhamnolipid in the composite oil displacement agent is 0.03-0.3 wt%, the final concentration of cocofatty acid diacetyl amide (CDEA 1:2) is 0.05-0.25 wt%, the final concentration of Sodium Dodecyl Benzene Sulfonate (SDBS) is 0.05-0.25 wt%, the final concentration of sodium cocoyl Glycinate (GCS) is 0.03-0.15 wt%, the final concentration of cocodimethyl betaine (BS-814) is 0.05-0.25 wt%, and the final concentration of oleamidopropyl betaine (OAB) is 0.03-0.15 wt%.
  5. 5. The preparation method of the rhamnolipid composite oil displacement agent comprises the steps of (1) aerobically fermenting pseudomonas aeruginosa CCTCC No. M2025023 to produce rhamnolipid to obtain rhamnolipid fermentation liquor, (2) centrifuging or filtering the fermentation liquor to remove thalli and other insoluble substances to obtain rhamnolipid fermentation supernatant, or removing thalli and other insoluble substances in the fermentation liquor, further extracting products to obtain rhamnolipid extract, (3) diluting the rhamnolipid fermentation supernatant, adding 5 additives according to the amount, or adding the rhamnolipid extract and the 5 additives according to the amount into water, stirring, dissolving and mixing, and adjusting the pH value to 7.0-9.5 to obtain the rhamnolipid composite oil displacement agent, and (4) barrelling the rhamnolipid composite oil displacement agent.
  6. 6. The rhamnolipid composite oil displacement agent of claim 4 wherein the surface tension of the composite oil displacement agent is less than or equal to 30 mN/m and the interfacial tension is less than or equal to 0.5 mN/m.
  7. 7. The rhamnolipid composite oil displacement agent of claim 4, wherein the emulsifying activity index EI 24 of the composite oil displacement agent on crude oil is more than or equal to 65%.
  8. 8. The rhamnolipid composite oil displacement agent of claim 4, wherein the core modulus of the composite oil displacement agent improves recovery ratio by more than or equal to 10%.
  9. 9. Use of a rhamnolipid composite oil displacement agent according to claim 1 for enhanced oil recovery.

Description

Rhamnolipid composite oil displacement agent and preparation method and application thereof Technical Field The invention relates to the technical field of oil extraction agents in oil fields, in particular to a rhamnolipid composite oil displacement agent and a preparation method and application thereof. Background ‌ Petroleum is a core energy source and an industrial raw material in the modern society, and is strategic resource ‌ for supporting the economic operation of society and guaranteeing the national energy safety. Petroleum is an economical "blood," for example, petroleum can provide fuel power for transportation, industrial materials for the chemical industry and ‌ manufacturing industries. ‌ ‌ petroleum is also an energy-safe "ballast". The crude oil in China has over 70 percent of external dependence, the yield of the old oil field is over 90 percent of that of the old oil field in China, but the recovery ratio is generally low, and the exploitation difficulty is gradually increased. By improving the petroleum recovery ratio through the technical means, more crude oil underground can be efficiently and economically extracted, the service life of an oil field can be prolonged, the sustainable development of the oil field can be promoted, and the competitiveness and the risk resistance of the oil field can be improved. In a word, the improvement of the petroleum recovery rate is very important to promote the high-quality development of oil fields, effectively relieve the resource taking over pressure and support the energy safety. At present, oil exploitation is mainly based on chemical oil displacement technologies such as ternary complex flooding and the like. Although the chemical oil displacement agent can greatly improve the petroleum recovery ratio, long-term use of the chemical oil displacement agent can also cause reservoir damage, increase water treatment difficulty and harm to ecological environment, and the comprehensive use cost of the chemical oil displacement agent is high. Therefore, aiming at the requirement of improving the oil recovery ratio, the development of the novel bio-based oil displacement agent with high efficiency, environmental protection and economy has important application value for realizing green and sustainable development of oil fields. ‌ Rhamnolipid (Rhamnolipids) is a glycolipid biosurfactant produced by microbial fermentation. Rhamnolipids can lower the interfacial tension of oil/rock and oil/water, disperse emulsified crude oil, and change rock wettability. Compared with the traditional chemical surfactant, the rhamnolipid has the advantages of good environmental compatibility, biodegradability, high activity and the like. The rhamnolipid is used as an oil extraction agent, so that the environment-friendly development requirement of an oil field is met. However, the use of rhamnolipids alone as oil displacing agents has the following limitations. Rhamnolipids, although capable of reducing oil-water interfacial tension, often have difficulty in reducing interfacial tension to very low levels when used alone, affecting crude oil displacement, and limited recovery. The production cost of rhamnolipid is higher, and when the rhamnolipid is used alone, a certain oil displacement effect can be achieved by using a large amount of rhamnolipid, so that the use cost can be increased. ‌ rhamnolipid is easy to adsorb or degrade in stratum when being used alone, reduces effective concentration, and influences oil displacement effect ‌. ‌ rhamnolipid has various structural compositions, and different structural types of rhamnolipid have different oil displacement activities. The rhamnolipids have limited emulsifying and interfacial activities when used alone, and are difficult to cope with complex reservoir types. The rhamnolipid compound oil displacement system can synergistically enhance the emulsifying activity and the interfacial activity through structural complementation, and the rhamnolipid alone lacks the synergistic effect. In summary, when rhamnolipid is used alone as an oil displacement agent, the recovery efficiency improvement effect is limited. The invention develops a rhamnolipid composite oil displacement agent based on rhamnolipid with a specific structure produced by microbial fermentation, and provides a novel oil extraction agent for oil field development. Disclosure of Invention In order to solve the problems in the prior art, the invention provides a rhamnolipid composite oil displacement agent, and a preparation method and application thereof. The invention discloses an oil displacement related activity parameter of rhamnolipid with a specific structure, which is produced by fermenting pseudomonas aeruginosa CCTCC NO. M2025023, and further develops a rhamnolipid composite oil displacement agent through compound system research. The rhamnolipid composite oil displacement agent has high oil displacement activity, simple and convenient preparation, eco