METHOD FOR DETERMINING POLLUTION DEGREE OF OIL BED WITH MICROFLORA Russian patent published in 1997 - IPC

FIELD: oil and gas production. SUBSTANCE: to predict oil bed pollution degree, a liquid containing no microorganisms is preliminarily filtered through porous medium and variable filtration characteristic is recorded. Thereafter, culture liquid is filtered within shortened time interval sufficient to determine kinetic constants of microflora development in porous medium derived from relationship: Z = Z_o•e±Kτⁿ, where Z is measured variable characteristic of culture liquid filtration process; Z_o the same for microflora-free liquid; K (in min^-n)and n kinetic constants of microflora development; and τ culture liquid filtration time, min. Variable characteristics for any time moments are then calculated and oil bed pollution degree (γ) is determined from relationship: γ = Z_pol/Z_o where Z_pol is variable filtration characteristic calculated. According to invention, as recorded characteristic of culture liquid filtration process in porous medium, pressure drop at constant culture liquid filtration rate or culture liquid filtration rate at constant pressure drop are utilized. EFFECT: increased reliability of prediction when accessible laboratory equipment is only needed. 2 cl, 2 tbl