WEIGHTED DRILLING MUD Russian patent published in 2011 - IPC C09K8/20 

FIELD: chemistry.

SUBSTANCE: invention relates to oil and gas industry, in particular to weighted drilling mud used in drilling wells under conditions of abnormally high formation pressure. The weighted drilling mud contains the following, wt %: gaize 5-10, stabiliser reagent - carboxymethyl cellulose KMC-900 0.2-0.3, calcium chloride 2.0-4.0, floatation agent T-80 1.1-3.5, potassium hydroxide 0.08-0.15, lubricant additive SMAD 0.3-0.5, unifloc 0.001-0.004, condensed spent sulfite-alcohol liquor KSSB-2M 3.2-7.1, barite 15-50, water - the rest.

EFFECT: more efficient drilling.

2 tbl, 9 ex