Abstract
Sievert and Loeffler have recently presented data on the cleaning behaviour of a range of non-woven fabrics when subjected both to reverse gas flow and to mechanically induced acceleration. In common with other workers in the field they suggest that, for reverse flow, cleaning is easier if the deposited cake mass is greater; i.e. the pressure drop required across the filter in order to release the cake, and the reverse gas flowrate through it, are both reduced for thicker cakes. In this short paper Sievert and Loeffler's results show that the stress which must be imposed on the cake in order to detach it, is independent of cake loading and that this level is consistent with the stress required to detach the cake by mechanically induced acceleration.