HEAT-RESISTANT BIOPOLYMER DRILLING MUD Russian patent published in 2020 - IPC C09K8/10 

FIELD: mining.

SUBSTANCE: invention relates to biopolymer clay-free drilling mud used for opening productive strata of directional and horizontal wells with super long-distance wastes. Heat-resistant biopolymer drilling mud contains, wt%: BIOPOL xanthum gum 0.15–0.25; modified starch MULTISTAR 0.75–1.25; polyanionic cellulose ANIPOL HB 0.12–0.2; sodium hydroxide 0.04–0.4; water-soluble salt of silicic acid 0.37–0.6; lubricating additive BL-SALT 0.95–1.55; potassium chloride 4.0–6.0; carbonate weighting agent 1.5–3.2; heat stabilizing additive 0.55–0.9; calcinated soda 0.05–0.1; bactericide 0.05–0.1; sulphonated bitumen SULPHOBIT 0.7–1.1; antifoaming agent Penta-480V 0.05–0.1; organic additive BIO XX, inhibiting swelling and scattering of clay-containing rocks, 0.7–1.1; polyglycols with cloud point of 70–130 °C with mineralization of 50–100 g/l 1.35–2.2; barite filler to 44.0; water – balance.

EFFECT: providing stability of filtration, structural-rheological, inhibiting and lubricating properties of drilling fluid in conditions of high temperatures up to 130 °C.

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