Our Cover Illustration
On the first page cover of this issue of FIRE AND WATER ENGINEERING is illustrated the water filtration plant of the East Liverpool, Ohio, water works. The tendency in filter installation is toward efficiency, combined with economical administration, and one of the principal features aimed at by designers is that of automatic control in the different operations of filtration. In the case of the plant under consideration, which consists of six one million gallon units, the Ohio river water, which is of comparatively high turbidity and low alkalinitv. is treated with lime by manually controlled dry-feed machines and with coagulant by means of an automatically controlled solution feed system. The use of lime is necessary, practically at all times, as the water of the Ohio is extremely low in alkalinity. A small vertical baffle plant mixing chamber and a sedimentation basin of eight hours’ retention meet this condition of the water, after which it flows by gravity through the filters, the operation of which is controlled by hydraulic valves from control tables on the main floor. The water is then collected by a false bottom strainer system and piped through venturi type rate controllers into the clear water reservoir situated under the filters. The filtered water is also sterilized with liquid chlorine. The plant is an excellent example of a small, compact and economical installation.