Trace Pollutant Emissions From The Processing Of Non
----- epa-22 trace pollutant emissions from the processing OF non-metallic ores by katari, isaacs, and devitt pedco-environmental specialists, inc. suite atkinson square cincinnati, ohio 45246 contract no. 321, task roap no. auz- program element no. epa project officer: oestreich control systems laboratory pebble and ball mills the simplest form of a ball mill is cylindrical, horizontal, slow-speed rotating drum containing a mass of balls as grinding media. when other types of grinding media such as a flint or various ceramic pebbles are used, it is known as a pebble mill. the ball mill uses steel, flint, porcelain, or cast iron balls.