ON THE USE OF KOLA NEPHELINE CONCENTRATE FOR HYDROSEALING WELLS, UNDERGROUND VESSELS WITH RADIOACTIVE BRINES AND IN PRO-DUCTION OF CALCINED PHOSPHATES
The article states results of studies of non-traditional usage of Kola nepheline-containing raw material - nepheline concentrate. Nepheline has particular properties - ability to dissolve easily in weak acids with subsequent formation of sols and gels first, and then - crystalline hydrates. Transformation of nepheline to gel-like mass opens a prospect for creation of production of various hydrosealing compositions with prescribed properties. Main peculiarity of the latter is possibility to stay within controllable periods of time in condition close to mineralized solution, having high permeability in porous and crevassed grounds and rocks. After expiration of given time period these solution transform to gel fully clogging pores and crevasses of the latter. This property of nepheline opens prospect for developing a technology of production of gel-like hydrosealing materials for hydrosealing oil and gas wells, tailing dumps and underground cavities with saline radioactive solutions. At the same time, the transition of gel-like mass in the air to crystalline hydrates may provide for salvaging acid waste waters of various productions. Interesting direction in usage of nepheline concentrate is its caking with phosphorous-containing raw materials, which will enable production of calcined phosphates fertilizers.