Inflow rate of water to small-scale water treatment plant for remote settlement - limited by rocking cradle over upper filter with surrounding overflow-prevention rim in stack, preventing surge of water into filter stack

摘要

A waste water treatment plant for a small, remote settlement has a water pre-treatment and settlement section, followed by a biological treatment stage and a soakaway shaft. The upper section of the biological treatment stage is linked by an inlet pipe (18) with the pre-treatment and settlement section. Incoming water is released onto the uppermost (6') of a series of stacked (19) filters (6) and filters vertically through the stack to the outlet (5). The novelty is that: (a) the uppermost filter is held in a cradle (8) with side-walls extending vertically above the filter surface; (b) a V-shaped cradle (12) is located between the water inlet pipe (18) and the uppermost filter (6); the cradle (12) has a pivot hinges at each end, facilitating tipping left and right about its longitudinal axis, and has a central dividing panel (15) along this axis, forming two water chambers, and (c) a ball float (20) is linked to a water inflow (18) control assembly.