Study on the effect on fine coal flotation performance produced by depressing agent at Tunlan Coal Preparation Plant

The fine coal flotation system of Tunlan Coal Preparation Plant is operating with a low efficiency and high cost. For tackling this problem,experiments have been conducted on the performance of the flotation system with the use of kerosene as collector and sec. Octyl alcohol as frother and sodium silicate,sodium trimetaphosphate and sodium carboxymethyl cellulose as depressing agents. It is aimed to making known the law of the influence produced by the use of each kind of depressant and determine its optimal dosage. As evidenced by test result,within the extent of the experiments,the flotation performance tends to improve gradually with the increase of dosage of depressing agent and become deteriorated with over-dosage. It is found that when CMC is used at a dosage of 40 g/t,a best flotation performance as follows can be expected: concentrate yield and ash -69.72% and 9.81%; recovery rate of combustible matter -78.60%; and flotation performance index -44.40%.