REAGENT FOR TREATING CLAY DRILLING MUDS, METHOD OF PREPARATION THEREOF, AND METHOD OF TREATING CLAY DRILLING MUDS Russian patent published in 2002 - IPC

FIELD: oil and gas production. SUBSTANCE: reagent contains 2.5-10% cellulose or starch ethers and esters and 90-97.5% sulfate soap (calculated for solids). Reagent is prepared by mixing ingredients with residual moisture up to 30% until homogenous pasty state is attained, ageing the mixture for 24-28 h, granulation, drying in air flow at 50-70 C, and removal of water within the limits from 35 to 30 wt %. Clay drilling muds are treated with 0.25 to 1.0 % of reagent (based on drilling mud). Reagent enhances inhibiting properties of clay drilling muds, increases coefficient of restoration of productive formation owing to reduced filtration of drilling mud and softening effect on reservoir rocks, reduces sticky properties of clay drilling muds owing to reduced shift stress and friction coefficient across the filtration crust, and reduces wear of drilling tools because of increased lubricating property of drilling muds. EFFECT: improved working characteristics. 3 cl, 3 tbl