BIOPOLYMER DRILLING MUD SBK-UNI (PLUS) Russian patent published in 2015 - IPC C09K8/10 

FIELD: chemistry.

SUBSTANCE: invention relates to biopolymer drilling mud used when drilling wells, including horizontal, slanted and recovery wells by sidetracking. The biopolymer drilling fluid contains, wt %: polymer fluid loss additive - carboxymethyl cellulose with degree of substitution of 300-1300 in the form of two types of carboxymethyl cellulose with a different degree of substitution in ratio of 1:1 2.4-3.2; a xanthane type biopolymer 0.2-0.5; lubricant additive - glycoil reagent 0.5-1.0; different-fraction filler - barium sulphate up to 40.0, bactericide 0.01-0.2; sodium hydroxide 0.01-0.06; water - the balance.

EFFECT: improved structural-rheological properties of the biopolymer drilling mud, high retention and transporting capacity, while maintaining filtration properties.

4 cl, 3 tbl, 8 ex