Study on coal slime reflotation and technological process transformation at Xinzhuang Coal Preparation Plant

with an aim to reduce ash of clean coal and recover combustible matters with a high calorific value, an analysis is made of the quality of the tailing and concentrate products of the flotation machines first, second, third and fourth cells, in order to explore the feasibility of lowering ash of clean coal and recovering combustible matters from coal slime. Considering the capital input, space and operating costs, it is intended to select an appropriate reflotation process in line with the plants specific considerations. Finally, a 3-product reflotation process consisting of a rougher and a cleaner is selected. The renovation work has met with a significantly good result as evidenced by the reduction of calorific value of coal slime from 7.06 MJ/kg to 3.23 MJ/kg with a drop of 3.83 MJ/kg, a rise of yield of clean coal by 46,000 tons and an additional gain of economic revenue of 83.35 million yuan per year. And moreover over 40,000 tons of flotation middlings with a high calorific value can be supplied to the plants internal power station after direct mixing with clean coal.