Analytical representation of washability curves with application in the simulation of gravity concentration methods

The present level of economy sets more and more stringent requirements for product quality, equipment and technologies used in the coal preparation industry. In this regard, methods of process optimization and efficiency improvement, based on the information technologies, become of current interest at existing facilities as well as in designing of new ones. Mathematical models of preparation processes are of particular relevance in the design and operation of concentrators, because they allow exploring various options for process flowsheets and determining optimal process parameters. The choice of process parameters is based on analytic representation of washability curves using numerical analysis. The results of float-and-sink testing, presented in graphical form as washability curves, allow making a theoretical balance of coal processing products and establishing an optimal separation density to reach the maximum production of clean coal. Usually, their plotting is conducted manually on graph paper, which is a very time-consuming and laborious procedure. This issue is arising, from time to time, in publications of authors all around the world, but there is still no commonly accepted procedure designed. In the present article authors made an attempt to examine different existing methods for analytical representation of coal washability curves suitable for the application in computer simulation of gravity concentration processes. During the work on this topic, a software complex has been developed. Description of the developed software and an example of its use for the purpose of flowsheet selection for the coal preparation unit is provided.