METHOD OF DEVELOPMENT OF BURIED WATER-FLOODED PLACERS Russian patent published in 2009 - IPC E21C41/22 E21C45/00 

FIELD: mining.

SUBSTANCE: method of development of buried water-flooded placers includes preliminary concentration of useful component of sands in lower portion of placer by means of excitation of elastic oscillations in placer sands and successive stoped excavation. A tubular shell is inserted into the placer; the height of the shell exceeds the distance from the surface to the float of the spacer. Excitation of elastic oscillations in spacer sands is performed by means of their transmitting from the surface via the tubular shell. After compressive force has been formed from interior surface of the shell onto contacting surface of covering volume of barren material and after completion of vibratory processing the hydraulic stoped excavation of lower part of the placer is carried out; washing water is supplied via sprayers assembled at walls of the tubular shell and pulp is withdrawn via soil intake openings located at walls of the tubular shell between the sprayers. Also after completion of stoped excavation of lower part of the placer the stoped space is backfilled by supplied backfilling pulp and water withdrawal. Further backfilling pulp is formed from mixture of water with barren rock, for instance, with tailings of sand concentration. After backfilling of excavated space pressure onto surface of covering volume of waste material contacting with interior surface of the shell is dropped to zero and the shell is extracted.

EFFECT: increased selectivity of excavation.

3 dwg