On the Economically Optimal Design of Air Filter

Abstract

The annual cost of an air filter is formulated in terms of the fixed and power costs of a fan, the fixed cost of an air filter, and the renewal cost of a filter medium. For an automatic renewal-type air filter, in particular, the cost of a medium is estimated considering the merit of a partial renewal operation. For several typical media, the optimal filtering velocity and the operating pressure drop (final value in a panel-type, and average value in an automatic renewal-type) are then calculated for various of flow rate and dust concentration. The values of various coefficients for computations were practically decided by inquiring of several makers and users, Approximate optimal solutions are analytically derived and the sensitivity of various parameters on the optimal solutions is discussed.
For example, it is concluded that the optimal conditions are remarkably affected by dust concentration, or the pressure drop characteristics of a medium, but hardly at all by flow rate. In an automatic-renewal type, it is shown that 20% cost reduction at most is obtained by a partial renewal operation.