METHOD OF PRODUCING GLAZED ALUMINOSILICATE MICROSPHERES Russian patent published in 2014 - IPC C04B18/04 

FIELD: chemistry.

SUBSTANCE: invention relates to production of hollow aluminosilicate microspheres from flue ash of coal power plants, suitable for use at high hydrostatic pressure as filler for drilling and cementing slurry for deep oil and gas wells and for producing well workover. In the method of producing hollow aluminosilicate microspheres, which involves separating aluminosilicate microspheres from flue ash of thermal power plants, the microspheres are treated with a glazing substance by mixing an aerosol of sprayed microspheres and an aerosol of the sprayed glazing substance selected from: methyltrichlorosilane, methyldichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, phenyltrichlorosilane, vinyltrichlorosilane, methylphenyldichlorosilane, tetraethoxylane, triethoxylane, methyltriethoxylane, hexamethyldisilazane and a mixture of at least two thereof; the aerosols are sprayed with a vapour-air mixture; the mass of the glazing substance is 0.7-2.5% of the mass of the microspheres; said treatment is followed by drying by heating in a stream of the vapour-air mixture. The invention is developed in subclaims.

EFFECT: high resistance to hydrostatic pressure, providing suitability for use at hydrostatic pressure of 400-500 atm of the filler for drilling and cementing slurry in deep oil and gas well conditions.

4 cl, 11 ex