HYDROCARBON BASED MUD Russian patent published in 1995 - IPC

FIELD: when drilling, to sink unstable clay, agrillites, salts, as well as when sinking zones of abnormally high pressure in formations bearing CO, CO₂ , H₂.. SUBSTANCE: mud composition has a diesel fuel of 255 - 360 C boil temperature or oil (48.84 - 14.46 per cent by weight), highly oxidized bitumen (9.411 - 1.218), quicklime (18.99 - 1.365), water (0.75 - 0.01), NP-3 sulfonmethane (0.22 - 0.183), YaRM-1 oil-bearing addition, batire modified with sodium tripolyphosphate (21.48 - 82.55). As YaRM-1 addition added the barite capacity of the mud increased by a factor of 1.3 (39.21 and 60 per cent by volume). It results in its density increasing from 2200 to 2520 kg/m³,, normal viscosity decreasing by a factor of 2.3 (70 and 30 s), static shift stress decreasing by a factor of 23.5 (141 and 6 dPa), filtration loss decreasing by a factor of 11.4 (25 and 2.2). EFFECT: increasing barite capacity (density) to decrease its viscosity, structure strength and to decrease loss when filtration. 5 tbl