METHOD OF STIMULATING OIL FORMATION WITH MICROORGANISMS AND PHYSICO-MECHANICAL TREATMENT Russian patent published in 1999 - IPC

FIELD: oil producing industry. SUBSTANCE: method is characterized by that treatment of bottom-hole formation zone and cleaning of downhole equipment from paraffin deposits and injection of suspension of microorganisms in aqueous solution of nutrient substances and chemical reagents are carried out under conditions optimal for activity of microorganisms in combination with physico-mechanical treatment of formation. Preliminarily, prior to formation treatment, casing string is perforated in the interval of producing formation. Then formation is subjected to intensive draining for withdrawal of colmatage products and clogging agents with the help of implosive and swabbing devices. Compositions of nonionic surfactants based on hydrocarbons are used for hydrophobization of porous channels of bottom-hole formation zone prior to perforating operation. EFFECT: increased microbiological effect on bottom-hole formation zone of oil-bearing formation in the necessary direction to restore its productivity and increased oil recovery. 2 cl, 1 tbl