Study On The Surface Properties Of Low-Rank Coals And The Selection Of Flotation Regents

In our country,coal is the main energy.In order to meet the needs of national economic development for energy,the high degree of metamorphism of coal was mined and utilized for a long time,and the storage is less and less,while low rank coal having large reserves、buried shallow and easy exploitation,it has not been processed and utilized very well.Coal preparation is the most economical and effective way to promote the clean and efficient utilization of coal,facing the Great pressure of the environmental problems,the in-depth preparation and processing of low rank coal has been imminent. Flotation is the most effective method for treating fine slime.Because the low rank coal has many oxygen groups、poor surface hydrophobicity and high porosity,conventional flotation technology can’t meet the requirement of the low rank coal,the flotation technology of low rank coal has becoming the bottleneck to improve the technology of power coal washing rate.Studying the surface properties of low rank coal,developing the effective flotation reagents to enhance the surface hydrophobicity of low rank coal, and to overcome the problem of low rank coal’s flotation,it is the urgent demand of the coal industry, becoming the development direction of technology in the field of coal flotation.In this paper, the low rank coal —long flame coal and non caking coal are chose as the research object, and the middle rank coal—gas coal is chose as control object,exploring initially the low rank coal’s surface properties and the flotation agent which is suitable for low rank coal.Firstly,after crushing the three kinds of coal samples,through the 0.5mm sieve,and the pulverized coal which under the screen were used as the experimental study of flotation.Then,studying the physical and chemical properties of coal samples which are related to the flotation process.Finally, comparing the effect of five kinds of collectors on the flotation of three kinds of coal,screening relatively good flotation reagents.By examining the change of XPS energy spectrum of coal particles before and after fiotation,inferred the adsorption of flotation reagent on the low rank coal surface is physical adsorption.The relative content of each group was calculated by the calculated results, in the flotation process found that,it is the oxygen containing groups of the collector bond interaction with the oxygen containing groups on the surface of the low rank coal,make the collector cover on the coal surface and the clean coal particles float.In this paper,through the study of the occurrence form of oxygen containing functional groups and surface properties of the low rank coal,exploring the adsorption mechanism of flotation reagent and low rank coal surface,the theoretical basis and experimental data have been established for further study of flotation reagent suitable for low rank coal,it has a certain role in promoting low rank coal flotation technology progress.