METHOD, MINERAL MATRIX BLOCK AND DEVICE FOR IMMOBILIZING RADIOACTIVE WASTES Russian patent published in 2002 - IPC

FIELD: environment protection; recovery of radioactive wastes. SUBSTANCE: method includes mixing radioactive wastes with oxidant, reducer, and mineral dope, filling clearance between external and internal vessels with powdered heat-insulating material, charging mixture obtained into internal vessel, heating mixture by initiating exothermic reaction between its oxidant and reducer, producing molten end product , and cooling it down. Steam-and-gas products of exothermic reaction are also decontaminated. Proportion of mixture components is as follows, mas.%: radioactive wastes, 10-45; mineral dope, 1-27; oxidant, 31-45; reducer, 11-30. Used as oxidant is vanadium pentoxide or its mixture with potassium permanganate. Silicon or silicon-titanium alloy, or silicon mixed up with silica calcium and/or with silicon- titanium alloy is used as reducer. Heat-insulating material is charged before mixture. Its layer thickness within internal vessel is not to be smaller than size of clearance between external and internal vessels. Device implementing this method has external and internal vessels, exothermic reaction initiating unit, gas decontamination unit, and incoherent auxiliary base. External-to-internal vessel diameter ratio is 1.4-2.5. EFFECT: enhanced safety, improved quality of end product, enlarged functional capabilities, reduced cost, reuse capability. 4 cl, 2 dwg