八雲選鉱場の操業について

抄録

This paper describes about the lead-, zinc- and manganese flotation at Yakumo dressing plant of Chugai Mining Co., Ltd., which turned in full operation in April 1954.
The deposit of Yakumo mine is the hydrothermal fissure-filling vein which consists of banded vein of sulfide minerals such as pyrite, galena and sphalerite, and of rhodochrosite. Only specific are of commercial value at that time has been selectively mined, rejecting and remaining others unmined.
The differential-flotation plant which has a capacity of 80 tons per day was constructed with the purpose to beneficiate such minerals. Prior to the flotation, ores are washed by washing trommel to remove primary slimes. Large circulating load in combination of a grate mill and a rake classifier prevents over-grinding and harmful effects of secondary slimes on soap flotation of manganese ore, together with desliming cyclone ahead of manganese flotation circuit.
Two combined sulfide froths, one is lead-zinc and the other mainly zinc, are floated in bulk-flotation circuit, and then differentially floated respectively. Manganese froth is floated from bulk-flotation tailing using oleic acid and AERO Promoter 824 in alkaline circuit. Conditioning agents are soda ash, sodium silicate and sodium cyanide. Sticky froth of manganese is destructed by water spray at thickener. Also water spray assists washing out adhered viscous reagents and filterimgofsuchfrothattankers.Warmimgofsupplywaterbymimethermalwaterincold season assists flotation recoveries, especially of manganese.