Abstract:
The raw coal product by Jilangde Mine has an ultralow contents of ash and sulfur and a high calorific value in nature, making it a high-quality material for preparing high-value coal products. However, there is no flotation process in the existing coal washing systems of Jiliangde Coal Preparation Plant. As a result, the coal slime is directly sold out as power coal, causing big waste of coal resource. For making it possible to realize high value-added utilization of the slime, a study is made on the flotation process which can better adapt to the coal and the optimal types and dosages of reagents, based on results of proximate analysis and tests on batch flotation and flotation process. As shown by study results, the use of the special agent for flotation of low-rank coal can lead to noticeable reduction of consumption of agent and improvement of flotation efficiency, a result much better than the traditionally used Diesel oil and the 2
# oil, and among the 1
# ~ 6
# agents, the 3
# agent is most effective; and at a total dosage of collector and frother of
2000 g/t and a ratio of 3:1, and through one roughing and two cleaning processes, a ultra pure concentrate product with a yield of 15.69% and an ultralow ash of 0.88% can be obtained. According to this agent regime, a flotation system consisting of one roughing process, two cleaning processes and two scavenging processes is designed. With the use of the flotation system, three graded concentrate products and a power coal product can be produced: 1
# concentrate product (yield - 13.64%, ash - 0.95%), 2
# concentrate product (yield - 10.41%, ash - 2.98%), 3
# concentrate product (yield - 6.35%, ash - 1.98%) and the power coal product (yield - 69.61%, ash - 10.41%). The use of the flotation system makes it possible for the Jilangde fine coal to meet the ash requirements for making high-quality coal products and hence promote the its value-added utilization.