LIGHT WEIGHT DRILL FLUID FOR OPENING-OUT OF PAYOUT BED Russian patent published in 2008 - IPC C09K8/10 

FIELD: oil and gas industry.

SUBSTANCE: invention refers to drilling of oil and gas wells and can be used for opening-out of high permeability payout beds with normal and abnormally low bed pressure, and also for prevention and elimination of troubles at drilling of intake beds. A light weight drill fluid for opening-out of a payout bed contains, % mas.: carboxymethyl cellulose 1.0-1.2; stillage bottoms of synthetic fatty acids production with a number of a hydro carbcon chain C₁₆-C₂₃ and with an acid number of not less, than 100 1.0-2.0; alkali 0.5-0.7; a surface active substance 0.1-0.2; aluminosilicate micro spheres 5-20; water- the rest.

EFFECT: upgraded quality of opening-out of payout beds and prevention of drill fluid intake.

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