COMBINED STABILISER BASED ON TALL OIL PITCH FOR TREATMENT OF DRILL FLUIDS AND METHOD OF ITS PRODUCTION Russian patent published in 2017 - IPC C09K8/35 

FIELD: oil and gas industry.

SUBSTANCE: combined stabiliser for the treatment of fresh and slightly mineralized drill fluids in the first version contains, wt %: diesel fuel or oil with a density of 0.78-0.92 g/cm³ 20; carboxymethyl cellulose, or hydrolyzed polyacrylonitrile, or starch 2-2.5; tall oil pitch 2-5; water is the rest. The combined stabiliser for the treatment of fresh and slightly mineralized drill fluids in the second version contains, wt %: diesel fuel or oil with a density of 0.78-0.92 g/cm³ 25-50; tall oil pitch 3-5; aluminium sulfate 3-5; water is the rest. The combined stabiliser for the treatment of fresh and slightly mineralized drill fluids in the third version contains, wt %: diesel fuel or oil with a density of 0.78-0.92 g/cm³ 25-35; carboxymethyl cellulose, or hydrolyzed polyacrylonitrile, or starch 2.5-4; tall oil pitch 2.5-3.5; aluminium sulfate 3-4; water is the rest.

EFFECT: improvement of rheological and filtration properties of drill fluids and reduction of filtration by 1,5-3 times while maintaining or increasing the values of static shear stress and apparent viscosity of fresh and slightly mineralized fluids, possibility of drilling in a hard terrigenous-carbonate section where it is difficult to retain the structure of the clay solution.

6 cl