Abstract: Disclosed is a solidified charge protection control for rotating grinding mills. A charged mill which has been shut down for a period of time is rotated to a pre-set angle of rotation and a bi-directional sensor feeds the signal caused by rotation to an electronic circuit where it is analyzed. Once the mill has reached the pre-set angle of rotation, it is declutched and the sensor feeds a second signal to the electronic circuit. These signals are compared to pre-set limits to determine if the charge has broken-up during the initial rotation so continuous operation of the mill can be commenced.

Abstract: An improved method of shredding municipal solid waste or garbage including the steps of introducing the solid waste into a tumbling mill having a diameter to length ratio of about 2.5:1 to 3:1, maintaining a negative pressure within the tumbling mill and maintaining a sufficient moisture content in solid waste. Shredding is accomplished by contacting the waste with irregular shaped grinding media within the tumbling mill.