METHOD FOR RESTORING DESTROYED OIL FIELDS Russian patent published in 2022 - IPC E21B43/00 E21B33/13 

FIELD: oil industry.

SUBSTANCE: invention relates to a method for restoring destroyed oil fields. According to the method, the geological and technological state of the deposit is analyzed, the system of drainage channels formed during the development of the productive reservoir between the injection and production wells along the restored section of the deposit is filled with a liquid working agent based on an aqueous cement solution with an added composition of fillers-additives selected according to the results of the analysis. The presence of a hydrodynamic connection between the injection and production wells in the field being restored is determined. Two days before the start of restoration work, oil production is stopped, all injection and production wells are stopped, and hydrodynamic processes in the subsurface are stabilized. In the injection well, tubing is installed 15 m above the perforation interval of the object being restored, technical means are installed and tied with technological pipelines with the injection well for the preparation and injection into the injection well of a working agent based on the aqueous cement solution with added fillers-additives prepared from sand and/or dredge, finely ground wood flour and sodium gluconate, the injection line is pressed to one and a half times the expected working injection pressure, from the dry part of the working agent using a cement mixing machine, a working agent is produced and simultaneously pumped into the injection well non-stop by a cementing unit. To maximize the coverage of the destruction zone, the first half of the working agent is pumped with a density of 1500-1600 kg/m³, the second with a density of 1600-1700 kg/m³, during the injection process, the density of the working agent injected into the well is controlled by sampling it every 5 tons of dry agent used, while monitoring the flow of the working agent into the producing well by sampling, when signs inherent in the selected sample of the working agent characterizing changes in the physical parameters of the liquid: specific gravity and/or electrical conductivity, the process of pumping the working agent into the injection well is stopped.

EFFECT: injection and production wells are closed in anticipation of the solidification of the working agent in the drainage channels until the restoration of the destroyed sections of the field.

3 cl, 4 dwg