SELECTION METHOD OF POLYMER GEL-FORMING COMPOSITION TO INCREASE OIL RECOVERY OF FORMATIONS AND WATERPROOFING WORK Russian patent published in 2013 - IPC C09K8/575 C09K8/588 

FIELD: oil and gas industry.

SUBSTANCE: in selection method of polymer gel-forming composition to increase oil recovery of formations and waterproofing work based on acrylamide polymer, a cross-linking agent and water, which involves determination of formation parameters for a certain well, experimental determination of characteristics of the above composition, including time of gel formation and static shear stress, calculation of initial pressure gradient, minimum radius of a gel screen and minimum volume of pumped composition, distance Rk in a zone that is located at some distance from injection well working face and where a gel screen shall be formed is set, temperature value is defined for the above distance as per the pre-built diagram of dependence of distribution as per distance in the formation of temperature values calculated considering temperature of pumped water, its pumping rate and time, temperature, porosity and heat conductivity of the formation, and pressure value as per the pre-built diagram of dependence of distribution as per the distance in the formation of pressure values designed as per the specified formula, and composition is selected based on the following conditions: time of gel formation at the temperature determined for the same zone, which is not less than time of composition pumping to that zone of formation, and initial pressure gradient is higher than depression to which the gel will be subject in the same formation zone.

EFFECT: improving processing quality in the formation zone that is distant from the well working face at simultaneous improvement of preservation period of quality of the installed screen due to reducing the influence of depression on gel-forming composition.

1 ex, 3 dwg