one rank one pension orop , or 'same pension, for same rank, for same length of service, irrespective of the date of retirement', is a longstanding demand of the indian armed forces and veterans.: p 1 the demand for pay-pension equity, which underlies the orop concept, was provoked by the exparte decision by the indira gandhi-led indian national congress inc government, in 1973, two years .
tank and vat leaching involves placing ore, usually after size reduction and classification, into large tanks or vats at ambient operating conditions containing a leaching solution and allowing the valuable material to leach from the ore into solution.
dbacks of leaching include its lower efficiency and the often significant quantities of waste effluent and tailings produced, which are usually either highly acidic or alkali as well as toxic e.g. red mud . there are four types of leaching: cyanide leaching e.g. gold ore ammonia leaching e.g. crushed ore alkali leaching e.g. bauxite ore
the washoe process, a variation of pan amalgamation, was developed in the 1860s by almarin b. paul and others, to work the ore from the comstock lode in nevada, united states washoe was an early name for the area; see washoe valley .: 41 in the washoe process, the copper pans were replaced by iron tanks with mechanical agitators. each tank 'pan' was circular, and commonly held 1,200 to .
ridgeway's gold deposits were microscopic and a complex, multi-step process was needed to refine the heaps of ore into gold bars. a mill was used to crush the ore to an extremely fine powder of 200 mesh. this powder was soaked in a mixture of sodium cyanide, lime and water in one of ten giant tanks.