INHIBITING BIOPOLYMER SOLUTION Russian patent published in 2021 - IPC C09K8/12 

FIELD: petroleum industry.

SUBSTANCE: invention relates to the petroleum and gas industry, in particular, to inhibited hydrocarbon-based drilling fluids applicable in building of boreholes in abnormal mining and geological conditions, slant and horizontal shafts composed of unstable rocks prone to caving, collapsing and swelling, as well as for primary completion of productive formations. The inhibiting biopolymer solution comprises, % wt.: calcium chloride CaCl₂ 1 to 3; potassium chloride KCl 3 to 5; potassium hydroxide KOH 0.005 to 0.01; xanthic-type biopolymer "Gammaxan" 0.20 to 0.30; starch reagent "Amilor" 2.0 to 2.5; chalk 2.0 to 8; complex action reagent "Devon-2l" 1 to 3; antifoaming agent 0.5 to 0.8; hydrocarbon base – petroleum of the Sugmut deposit 8 to 15; water the rest.

EFFECT: increased efficiency of the drilling fluid due to the preservation of filtration and capacity characteristics, improvement in the rheological indicators and lubricating characteristics, improvement in the inhibitory and anti-corrosive properties.

1 cl, 2 dwg, 2 tbl