Enhanced oil recovery

Abstract: Many microorganisms, especially bacteria, produce biosurfactants when grown on water-immiscible substrates. Biosurfactants are more effective, selective, environmentally friendly, and stable than many synthetic surfactants. Most common biosurfactants are glycolipids in which carbohydrates are attached to a long-chain aliphatic acid, while others, like lipopeptides, lipoproteins, and heteropolysaccharides, are more complex. Rapid and reliable methods for screening and selection of biosurfactant-producing microorganisms and evaluation of their activity have been developed. Genes involved in rhamnolipid synthesis (rhlAB) and regulation (rhlI and rhlR) in Pseudomonas aeruginosa are characterized, and expression of rhlAB in heterologous hosts is discussed. Genes for surfactin production (sfp, srfA, and comA) in Bacillus spp. are also characterized. Fermentative production of biosurfactants depends primarily on the microbial strain, source of carbon and nitrogen, pH, temperature, and concentration of oxygen and metal ions. Addition of water-immiscible substrates to media and nitrogen and iron limitations in the media result in an overproduction of some biosurfactants. Other important advances are the use of water-soluble substrates and agroindustrial wastes for production, development of continuous recovery processes, and production through biotransformation. Commercialization of biosurfactants in the cosmetic, food, health care, pulp- and paper-processing, coal, ceramic, and metal industries has been proposed. However, the most promising applications are cleaning of oil-contaminated tankers, oil spill management, transportation of heavy crude oil, enhanced oil recovery, recovery of crude oil from sludge, and bioremediation of sites contaminated with hydrocarbons, heavy metals, and other pollutants. Perspectives for future research and applications are also discussed.

Abstract: Surfactants are surface-active compounds capable of reducing surface and interfacial tension at the interfaces between liquids, solids and gases, thereby allowing them to mix or disperse readily as emulsions in water or other liquids. The enormous market demand for surfactants is currently met by numerous synthetic, mainly petroleum-based, chemical surfactants. These compounds are usually toxic to the environment and non-biodegradable. They may bio-accumulate and their production, processes and by-products can be environmentally hazardous. Tightening environmental regulations and increasing awareness for the need to protect the ecosystem have effectively resulted in an increasing interest in biosurfactants as possible alternatives to chemical surfactants. Biosurfactants are amphiphilic compounds of microbial origin with considerable potential in commercial applications within various industries. They have advantages over their chemical counterparts in biodegradability and effectiveness at extreme temperature or pH and in having lower toxicity. Biosurfactants are beginning to acquire a status as potential performance-effective molecules in various fields. At present biosurfactants are mainly used in studies on enhanced oil recovery and hydrocarbon bioremediation. The solubilization and emulsification of toxic chemicals by biosurfactants have also been reported. Biosurfactants also have potential applications in agriculture, cosmetics, pharmaceuticals, detergents, personal care products, food processing, textile manufacturing, laundry supplies, metal treatment and processing, pulp and paper processing and paint industries. Their uses and potential commercial applications in these fields are reviewed.

Abstract: Oil exploration and production actively began 100 years ago, from the present day. What we see now, known as primary production by natural flowing of oil by pumped wells. This covers 15% of oil recovery from reservoir. Later 25% of oil is recovered by water flooding is activated which is termed as secondary production. There is still significant oil left in the reservoir, if there is no proper employment of commercial valuable techniques for the production, the oilwell would simply be abandoned. But as the demand for oil kept raising new techniques emerged, eventually from those EOR was a successful in artificial up lifting of oil from the reservoir by providing enough pressure to the trapped oil to flow out of well. It is a tertiary production. EOR is different because it works from microscopic levels as well as by injecting the substances like gases, special liquid (polymers) and stream in the form of injection through injecting wells for oil recovery, which is termed as Enhanced Oil Recovery (EOR). The flooding in EOR, categorized as chemical flooding (by chemicals), stream or thermal injection (by stream) and miscible gas drive (CO2, N2 and LPG). These flooding will alter the physical and chemical properties of reservoirs for the flow of oil out of the well. EOR can unlock a percentage of 30-45% of trapped oil. After naming as successful technique in onshore for tertiary production, research is still going to implement EOR in offshore, to improve tertiary production and exploit hidden billion barrels of oil.

Abstract: Crude oil development and production in US oil reservoirs can include up to three distinct phases: primary, secondary, and tertiary (or enhanced) recovery During primary recovery, the natural pressure of the reservoir or gravity drive oil into the wellbore, combined with artificial lift techniques (such as pumps) which bring the oil to the surface But only about 10 per cent of a reservoir's original oil in place is typically produced during primary recovery Secondary recovery techniques to the field's productive life generally by injecting water or gas to displace oil and drive it to a production wellbore, resulting in the recovery of 20 to 40 per cent of the original oil in place In the past two decades, major oil companies and research organizations have conducted extensive theoretical and laboratory EOR (enhanced oil recovery) researches, to include validating pilot and field trials relevant to much needed domestic commercial application, while western countries had terminated such endeavours almost completely due to low oil prices In recent years, oil demand has soared and now these operations have become more desirable This book is about the recent developments in the area as well as the technology for enhancing oil recovery The book provides important case studies related to over one hundred EOR pilot and field applications in a variety of oil fields These case studies focus on practical problems, underlying theoretical and modelling methods, operational parameters (eg, injected chemical concentration, slug sizes, flooding schemes and well spacing), solutions and sensitivity studies, and performance optimization strategies The book strikes an ideal balance between theory and practice, and would be invaluable to academicians and oil company practitioners alike The following are the features of the book: Updated chemical EOR fundamentals - this book provides clear picture of fundamental concepts Practical cases with problems and solutions - this title provides practical analogues and experiences Actual data regarding ranges of operation parameters - this work provides initial design parameters Step-by-step calculation examples - this text provides practical engineers with convenient procedures