COMPOSITION FOR PREPARING HEAVY PROCESS LIQUIDS FOR FINISHING AND REPAIRING OIL AND GAS WELLS Russian patent published in 2010 - IPC C09K8/42 

FIELD: chemistry.

SUBSTANCE: invention relates to finishing and repairing oil and gas wells and can be used in conditions with anomalously high formation pressure and high temperature, for killing wells and different kinds of works during repair. The composition for preparing heavy process liquids for finishing and repairing oil and gas wells contains calcium nitrate, calcium chloride and a corrosion inhibitor - hexamethylenetetramine or ethylenediamine, as well as a hydrophobic coagulator - Sulfonol or Catapin and a scaling inhibitor - oxyethylidene diphosphonic acid or nitrilomethyl phosphonic acid in the following ratio of components, wt %: calcium chloride 25.66-71.94; calcium nitrate 27.3-71.8; said corrosion inhibitor 0.5-2.44; said hydrophobic coagulator 0.05-0.16; said scaling inhibitor 0.02-0.1. The collection of all the said components of the composition in the given ratio enables fast removal of all solid particles from the obtained solution during preparation of the process liquid, where the size of the particles is equal to 10^-9-10^-7 m, i.e. lie in the interval from nanometres to a fraction of micrometres.

EFFECT: new properties of the process liquid - hydrophobic coagulation and flocculation of colloidal microparticles of the solution and obtaining heavy process liquid containing not more than 0,01% solid particles.

1 cl, 1 tbl, 4 ex