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

FIELD: chemistry.

SUBSTANCE: invention relates to clayless biopolymer drilling muds, which are used to drill in severe mining and geological conditions. The biopolymer drilling fluid contains, wt %: low-viscosity polyanionic cellulose (degree of substitution 0.9, Brookfield dynamic viscosity <100 mPa·s) 0.2-1.5; high-viscosity polyanionic cellulose (degree of substitution 0.9, Brookfield dynamic viscosity >1000 mPa·s) 0.2-1.5; xanthane-type biopolymer 0.1-0.6; lubricant additive 0.07-3.5; alkali and/or alkali-earth metal salts KCl, NaCl, CaCl₂, MgCl₂, bischofite 3.0-40.0; sodium hydroxide 0.1-0.6; glycoil reagent inhibitor 0.5-1.0; bactericide 0.01-0.2; different-fraction filler - barium sulphate up to 80; water - the balance.

EFFECT: improved structural-rheological properties and heat resistance, salt resistance, reduced harmful environmental effect, fewer and lower concentration of components required to prepare the drilling mud, while maintaining inhibiting, lubricant, filtration and anti-seize properties.

3 cl, 1 dwg, 5 tbl, 3 ex