Automation of the Mud and Water Circulation Process at Coal-Preparation Plant - Initial Study

摘要

The preliminary research program for working out an automatic control system for the water and slurry circuit at a typical Polish coal preparation plant is reported. At the water and slurry circuits of these plants, both in Poland and in the United States, there are installed individual devices for local control, but there is a lack, for the time being, of sufficient information about steady-state and dynamic characteristics of these circuits to work out a full automatic control system. Under the research problem to be taken up, it is planning to carry out a full research on a chosen typical water and slurry circuit as a controlled plant, and to work out an automatic control system based on the results of that research. The designed system is to be tested under laboratory conditions, and next under service conditions at a chosen Polish coal preparation plant. A correct operation of the whole water and slurry circuit, apart from the fulfillment of the requirements of individual processes, required a series of conditions ensuring proper co-operation of the individual processes and facilities to be satisfied. The suitable quantity and quality of the media being transported between the individual installations should be ensued by using right size storage and mixing tanks. One of the fundamental problems is to ensure a proper flow of the thickened flotation refuse from a continuously-operating thickener to a filter-press operating in cycle. One ought to pay attention to the fact that dynamic properties of the storing and mixing tanks and interconnections between the individual facilities (great delays and time constants) reduce considerably the possibility of water and slurry circuit regulation. (ERA citation 08:022988)