Optimization of Flotation Conditions for Long-Flame Coal Mud by Response Surface Method

Abstract

With the application of modern coal mining technology and the fact that there are fewer and fewer high-quality coal seams, the quality enhancement and utilization of low-rank coal are gaining more and more attention. To solve the problems of high consumption of chemicals and low recovery of refined coal in the flotation separation process of low-rank coal, the long-flame coal from the Inner Mongolia Autonomous Region of China was selected as the research object, and the factors affecting the flotation process were analyzed and optimized by adopting the response surface method and establishing a regression model with high precision and reliability. The test results showed that the primary and secondary relationships of the factors on the fine coal yield were as follows: slurry concentration > frother dosage > collector dosage; and the primary and secondary relationships of the factors on the flotation refinement index were as follows: slurry concentration > collector dosage > frother dosage. The optimal conditions for flotation were 2453.09 g/t of collector, 795.84 g/t of frother, and 50.04 g/L of slurry concentration. Under these conditions, the fine coal yield was 51.51%, and the relative error of 53.71% was 4.27%. The flotation refinement index was 21.34%, and the relative error with the predicted value of 21.58% was 1.12%. The relative error of the experimental results was within a reasonable range, which indicated that the regression model obtained by the response surface method was highly reliable. The research results are of great significance to strengthen the comprehensive utilization of long-flame coal in full particle size and improve the economic benefits of coal enterprises.