METHOD FOR UNDERGROUND LEACHING OF MINERALS Russian patent published in 1995 - IPC

FIELD: mining industry. SUBSTANCE: ore body is opened by holes. Leaching solution is injected through injection holes. Productive solution is pumped out through producing holes. Then, pumping out of productive solution is discontinued and leached ore body is acted on by pressure pulses from holes with asymmetric distribution of energy. Pulse action is effected with spectrum of frequency range of less than 100 Hz and maximum spectral density of energy within the interval of 15-35 Hz. Before and after pressure pulse action, the content of useful component in productive solution is measured, and when its content reduces to initial value, pulse-wave action is renewed. Pressure pulse repetition period is maintained equal to period of natural oscillation of hole-bed system. Action is effected simultaneously through injection and producing holes with time shift between pulses from similar holes equalling half-period of natural oscillation of hole-bed system. EFFECT: increased recovery of useful component due to improved filtering ability and more uniform distribution in it of leaching solution. 3 cl