METHOD OF PROCESSING LOW-DRAINED AREAS OF OIL DRAWINGS Russian patent published in 2018 - IPC E21B43/267 E21B43/27 E21B43/24 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil industry and can be used to develop heterogeneous oil deposit with weakly drained areas. Method includes production of oil reserves by wells, conducting well studies, fracturing, application of in-situ thermochemical treatment using granulated magnesium and hydrochloric acid, injection of working agent into injection wells and selection of products from production wells. According to invention, reservoir with accumulated oil recovery from initial recoverable reserves of at least 50 % is selected, in well stock drilled into given deposit, Investigations are carried out to determine current reservoir temperature and map formation temperature distribution over reservoir area. Areas in which current reservoir temperature is lower than initial temperature by 5 % or more are isolated, preliminary each well of isolated sections is cleaned of deposits on walls of pipes by sequential injection of granulated magnesium in volume of 20–40 % of production column volume and 60–80 % – hydrochloric acid with concentration of 12–18 %, washed and reaction products are selected. Then, in wells of isolated areas where there is no water + oil contact, fracturing is carried out in which 10–40 % of injected propane by mass is replaced by granulated magnesium of same fraction as proppant fraction. First, proppant and magnesium of larger fraction are pumped in, then size of injected propane and magnesium fraction is subsequently reduced, then two or four times rim of 12–18 % of hydrochloric acid is injected and pumped with technical fluid, wells are mastered and put into operation. Further development with maintenance of reservoir pressure is conducted by pumping working agent – water heated to temperature that is sum of initial reservoir temperature and calculated heat losses along wellbore.

EFFECT: technical result is to increase oil recovery.

1 cl, 2 ex