OPERATION OF PERMAFROST ZONE OIL DEPOSIT Russian patent published in 2014 - IPC E21B43/16 

FIELD: oil-and-gas industry.

SUBSTANCE: proposed method comprises control over crude oil phase state. To prevent formation of solid phase in crude oil with paraffinic sediments, first, saturation of crude oil with paraffins is defined with due allowance for saturation temperature of degassed oil and content of paraffins. Influence of pressure and amount of gas dissolved in oil is evaluated under reservoir conditions with allowance for current seam pressure and crude oil gas content. Deposit operation conditions are set when seam pressure and pressure of oil saturation with gas are similar or equal while paraffins in oil are saturated or close thereto. At content of paraffins of 0.5-2 wt % in seam oil operation conditions are selected at seam oil extraction with pressure compensation by injection of cold water. Note that seam pressure is not decreased below initial pressure and phase state of seam oil with paraffins is not disturbed.

EFFECT: higher efficiency of the process.

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