Research Results of Coal Impact Grinding Process in the Pneumatic Transport Mill

The paper is devoted to the topic of current interest in developing the effective and energy saving methods of coal powder processing in the thermal power stations. One of the effective thin grinding methods is solid particles impact on a hard balk. This method can be implemented by the air stream particle acceleration and the particles impact on the angle pipes dash elements of a pneumatic transport mill. This device is designated for coal powder processing systems and makes it possible to combine the coal grinding and pneumatic transporting processes. The article looks at theoretical and experimental research results of anthracite grinding in the laboratory pneumatic transport mill and investigates the influence of the main factors on anthracite grinding process. We found that the air-coal mixture velocity, the angle of pipe’s turn in the transport pipeline, the mass concentration and the primary specific surface area of the grinded material contribute to the increase in specific surface area. The destruction work coefficient of the obtained particles allowed us to define the energy which is directly spent on coal grinding. The relative divergence of theoretical and experimental results doesn’t exceed 10 % that testifies to adequacy of the developed mathematical model to real processes of anthracite grinding in the pneumatic transport mill.

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