EFFECT OF DIFFERENT DESIGN PARAMETERS ON PERFORMANCE OF M. B. SETTLER

Abstract

There is a growing recognition of the role of protected water supply in improvement of health and economic and social development. But the conventional water treatment units are not suitable for use in rural areas and small communities due to their high capital and maintenance costs They also require skilled labour for their maintenance. The multibottom settling tank, as proposed, is economical both in capital and maintenance cost and practically requires no skilled labour for maintenance. The experimental study on pilot plant of about 3.0 M3 capacity has been carried out by varying depth of flow in settling tank from 0.25 M to 0.95 M, the angle of inclination of bottoms to horizontal, from 30° to 60°, the horizontal velocity from 4.0 to 20.0 cms/min.1 the surface loading from 1.66 to 33.33 litres/A.m.-min and detention time from 3.0 to 60.0 minutes. The results have been discussed in detail and it has been established that depth of flow as 50 cms and above, angle of inclination as 45°1 horizontal velocity as 12.0 cms/min, the surface loading as 6.66 litres/ sq.m.-min4 and detention time 15.0 minutes are quite suitable. Under these conditions of flow, the performance of the MBST was observed to be as good as that of conventional units:. If the H.V. and surface loadings are further reduced, it is expected that the 1BST may give better performance.