METHOD OF WATERPROOFING WELL ANNULAR SPACE AND COMPOSITION OF GROUTING MIXTURE FOR ITS IMPLEMENTATION Russian patent published in 2020 - IPC E21B33/138 C09K8/50 

FIELD: mining.

SUBSTANCE: group of inventions relates to mining and can be used in construction and repair of wells for various purpose. Method of waterproofing of annular space consists in that a hose is pumped into the annular space between the well wall and the casing pipe and a backfill mixture is pumped through the hose. For pumping two-channel hose with mixing chamber is used at the end, in process of pumping hose is lifted with rate of rise of level of formed material of waterproofing in annular space. When pumping into one channel of hose one component of grouting mixture is supplied – mixture of fly ash and water in weight ratio of 1:1 to 1.6:1, and another channel is supplied with another component of plugging mixture – hydroactive polyurethane resin, with following ratio of components, wt%: mixture of fly ash and water 88–94, hydroactive polyurethane resin 6–12.

EFFECT: improved quality and reduced duration of waterproofing of annular space and reduced consumption of grouting mixture and reduced fire hazard.

6 cl, 4 dwg