Method of maintaining the steady grain-size composition of rapid filter media

Summary

During the operation of rapid filters the grains of the filter media inevitably wear off and disintegrate which affects adversely the output of the filtration plants. To restore the design grain-size composition of the filter media the upper reduced in size layer is usually removed. This process is fairly labor-intensive and economically unjustified. The consistency of the grain-size composition of rapid filter media can be maintained eliminating labor-intensive processes of manual removal of fine grains and media unloading and rescreening. A method of maintaining the steady grain-size composition directly in the filter by intermittent washing with preestimated stabilization rate is suggested. The formulae for calculating the rate and process stages of stabilization wash are presented.

Key words

rapid filter , filter bed , filtration plant , grainsize composition , intermittent wash , filter media fineness stabilization