Used In The Flotation Separation Of Coal Sulfur Pilot Study

The experimental study of desulfating from some high-sulphur coal in Guizhou by flotation has been mainly expounded in this paper. And experimental results show that the content of sulphur in some high-sulphur coal in Guizhou can be decreased to below 3% through proper reagent system and separating flow.In this paper, four different samples of different places in Guizhou, as subjects investigated, have been studied by screen analysis based on phase analysis of sulphur of raw coal, and distribution situation of pyite of raw coal in different grades has been determined; in miniexperiments, experimental method of once single factor was employed and a better reagent combination with better effect of flotation ( depressant: YA; collector: kerosene and light diesel oil (1:1) ; frother: 2# oil) has been screened from large scale reagents; consumption of reagent, time of flotation and separating flow have been determined.Based on conditional experiments, through orthogonal experiment, the main factors affecting the effect of desulphuration have been found out and they are consumption of YA, consumption of kerosene and light diesel oil (1:1), consumption of 2# oil and PH value in order; and the main factors of affecting the effect of decreasing ash content are consumption of YA, consumption of kerosene and light diesel oil (1:1), PH value and consumption of 2~# oil in order. According to the experiments mentioned above, separating flow of once rough concentration, once concentration, once scavenging, mixed middings to be retreated and mixed middings scavenging has been finally determined, total sulphur has been decreased to 2. 81% and the rate of desulphuration has risen to 73. 31%.According to the microscope photographs of washed coal, tailing coal and midding, sulphur in samples exists mainly as monomer of pyite, and this sort of monomer of pyite enriches in tailing coal, distributes microcontent in washed coal and small quantity in midding.There are two polar groups, -SH group and - COOH group, in the molecular structure of YA. -SH group can intensively react with pyite and can be absorbed to the surface of minerals, while -COOH group performs hydrophilicity and forms water film on the surface of pyite, therefore hydrophobic coal and pyite are separated.