Recent advances and thinking in process intensification of low quality coal slime flotation

The primary energy storage conditions of “rich coal,lack of oil and less gas” determine the basic energy status of coal in China.However,as the most important source of carbon emissions,how to make coal contribution to the peak carbon dioxide emissions and neutrality is key issue for the whole industry urgently needs to think and solve.China’s coal resource endowment conditions are poor,rich in low-quality coal with high impurity.With the consumption of high-quality coal resources and the implementation of the national “double carbon” strategy,large-scale separation of low quality has become a strategic choice to ensure national energy security and high-quality green development of the coal industry.At present,the rapid development and popularization of heavy medium coal separation technology makes the separation of coarse low-quality coal becoming mature,while many challenges remain for flotation of fine low-quality coal slime (such as low-rank/oxidized coal,high ash refractory coal,etc.).Therefore,the basic function principle and process intensification requires further study.The present paper reviewed the recent advances in low-quality coal flotation from three aspects:the difficult-to-float and difficult-to-separate mechanism of low-quality coal,the interface regulation and fluid intensification of low-quality coal flotation.Finally,the new development direction and technical system of low-quality coal flotation process intensification in the future were put forward,including the new principle of low-quality coal flotation separation based on multi-scale micro-nano force analysis,the intelligent directional screening design of flotation reagent molecules based on single molecule force spectrum combined with deep learning,refine construction of pulp mixing and flotation flow field based on accurate energy adaptation,resourceful utilization and large-scale consumption of coal series solid wastes,and the construction of the whole chain intelligent demonstration project of low-quality coal flotation.The solution of the above key scientific and technological problems will provide new impetus for the high-quality development of China’s coal industry and the implementation of the national “double carbon” strategy.