DRILLING FLUID ON HYDROCARBON BASIS Russian patent published in 2012 - IPC C09K8/32 

FIELD: oil and gas industry.

SUBSTANCE: drilling fluid on hydrocarbon basis includes the following, wt %: liquid paraffin C₇-C₂₂ 52.7-56, organophilic clay powder 2.5-4.7, water 1.5-9.5, sodium formate or sodium acetate 1.5-4.7, asphalt mastic 5.6-7.9, glycerine ether of tall colophony 1.5-7.1, neutraliser of hydrogen sulphide 0.1-0.3, non-hydrophobisated weighting agent in quantity providing the specified density of the fluid. Non-hydrophobisated disperse chalk or barite is used as weighting agent.

EFFECT: maintaining rheologic and filtration parameters of drilling fluid at the required level.

2 cl, 4 tbl