The coal finds wide application in industries because of their abundance and low cost. Coal obtained from mines consists of lot of impurities in the form of rock. For industrial purpose, the need of high-grade coal (with density of 1.2 to 1.5gm/cc) is essential.The high–grade coal is obtained by “Floating Technique”. This technique employes washing of mine coal in a mixture of water and magnetite known as “Slurry”. Slurry has a density of approximately 1.5 to 1.9gm/cc.the high-grade coal will float and the coal with impurities will sink. Thus separating the high-grade coal from low-grade coal.
The quality of coal depends on the density of slurry. Hence the slurry should be monitored on L.C.D and information is sent to the control disc through the serial port and controlled continuosly. For this purpose slurry is made to flow through a pipe to whch the”radiometric density gauge” is mounted. A radioactive source and a detector is placed on either side of the pipe. The radiation emitted bye the source passes through the pipe and falls on the detector. The detector gets ionized and gives an output current inversely proportional to this density of the slurry. This signal is given to the BL2100 microcontroller as analog input. The software used in Dynamic C.