Microbial selective plugging of sandstone through stimulation of indigenous bacteria in a hypersaline oil reservoir

Abstract In Microbial Enhanced Oil Recovery (MEOR) oil mobility and oil recovery is increased by growing and reproducing microbes (bacteria) in oil reservoirs. The oil reservoir is either innoculated with a proprietry bacteria and then fed to grow or indigeneous microbes present are fed by the injection of a suitable nutrient identified from labotatory experiments. The metabolic by-products produced by these microorganisms causes a reduction in oil viscosity and interfacial tension and an increase in oil mobility. Although MEOR is not popular, the open literature has shown this to be a low cost mechanism that can be implemented with waterflood projects to increase the recovery of residual oil by another 1-5 %. In this study an oil sample from an oil reservoir in the South of Trinidad was selected and the indigenous bacteria present was identified to be mainly of the Bacillus species. A quantification of this indigenous bacteria by plate counts showed that the aerobic colony forming units (CFU) was about 1.5×106 CFU/ml whereas the observed anaerobic plate counts was about 9.0×102 CFU/ml. Growth of the indigenous bacteria was stimulated by innoculating the oil sample with five different nutrient formulations for a period of three weeks so as to select the most suitable nutrient. However, the growth in bacteria was too numerous to count even after one week. Experimental measurements showed that the sample innoculated with the nutrient broth formulation had the greatest change in oil properties. The reduction in oil viscosity was 49 % and the reduction in interficial tension was 17 %. The results from this study can be included in waterfloood simulation studies for suitable oil reservoirs in Trinidad to determine the added increase in oil mobility and oil recovery from a combination of waterflood and MEOR.

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KINETICS OF A BINARY MIXTURE DECOMPOSITION IN RELATIONTO THE EFFECTS ON OIL RESERVOIR

Oil and Gas Studies ◽

10.31660/0445-0108-2017-6-67-72 ◽

2017 ◽

pp. 67-72

Author(s):

A. I. Varavva ◽

V. E. Vershinin ◽

R. A. Idiatullin

Keyword(s):

Mathematical Model ◽

Aqueous Solution ◽

Binary Mixture ◽

Decomposition Reaction ◽

Oil Reservoir ◽

Thermal Pressure ◽

Temperature Growth ◽

Mixture Decomposition ◽

Kinetics Of ◽

Stimulation Of

The kinetic constants of the decomposition reaction of an aqueous solution of a binary mixture used for thermal-pressure induced impact on the bottomhole zone during stimulation of oil inflow are determined. The obtained constants allow predicting the effects of pressure and temperature growth in the reaction zone. A mathematical model is proposed that makes it possible to describe the kinetics of the reaction taking into account the escape of gas.

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Effects of 5-5'-Diphenyl-2-thiohydantoin (DPTH) and Thyroxine on the Ultrastructure and Chemical Composition of Rat Liver

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066917 ◽

1971 ◽

Vol 29 ◽

pp. 570-571

Author(s):

E. A. Elfont ◽

R. B. Tobin ◽

D. G. Colton ◽

M. A. Mehlman

Keyword(s):

Chemical Composition ◽

Rat Liver ◽

Future Study ◽

Mode Of Action ◽

Liver Mitochondria ◽

Rat Liver Mitochondria ◽

Effective Inhibitor ◽

Biochemical Effects ◽

Glycerophosphate Dehydrogenase ◽

Stimulation Of

Summary5,-5'-diphenyl-2-thiohydantoin (DPTH) is an effective inhibitor of thyroxine (T4) stimulation of α-glycerophosphate dehydrogenase in rat liver mitochondria. Because this finding indicated a possible tool for future study of the mode of action of thyroxine, the ultrastructural and biochemical effects of DPTH and/or thyroxine on rat liver mere investigated.Rats were fed either standard or DPTH (0.06%) diet for 30 days before T4 (250 ug/kg/day) was injected. Injection of T4 occurred daily for 10 days prior to sacrifice. After removal of the liver and kidneys, part of the tissue was frozen at -50°C for later biocheailcal analyses, while the rest was prefixed in buffered 3.5X glutaraldehyde (390 mOs) and post-fixed in buffered 1Z OsO4 (376 mOs). Tissues were embedded in Araldlte 502 and the sections examined in a Zeiss EM 9S.Hepatocytes from hyperthyroid rats (Fig. 2) demonstrated enlarged and more numerous mitochondria than those of controls (Fig. 1). Glycogen was almost totally absent from the cytoplasm of the T4-treated rats.

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