ON GAS RECYCLING AS A MEANS OF IMPROVING THE OPERATION OF CYCLONES

A comprehensive theoretical analysis is provided to demonstrate that t he idea of the recycling of outlet gas of a cyclone as a means of impr oving its dedusting efficiency may be misleading. When the effects of particle size and solids loading are incorporated in the saltation vel ocity equation, it is predicted that the overall dedusting efficiency will be reduced if such a gas recycling system is adopted. It is also shown that the traditional equation for dedusting efficiency involving the cut size of particles may become invalid once the saltation veloc ity of the cut size exceeds the corresponding inlet gas velocity.