Patent ID: 7032609
Filing Date: 2006-04-25
Classification: C02F,Y10T

Abstract:
1. A vacuum feed system for feeding liquid chemical to a liquid to be treated flowing in a conduit, the system comprising, a container for containing a supply of liquid chemical to be fed, a vacuum regulated flow control valve having an inlet connected to the container and an outlet, the flow control valve being operable to maintain a uniform pressure at its outlet; adjustable valve means for adjusting the feed rate of the liquid chemical being fed, the adjustable valve means having an inlet connected to the outlet of the vacuum regulated flow control valve and an outlet, a first one-way check valve having an inlet connected to the outlet of the adjustable valve means, and an outlet, and a venturi ejector connected in the conduit for producing an area of negative pressure in the conduit upon flow there through of liquid to be treated, the first one-way check valve having its outlet connected to the venturi ejector at the area of negative pressure and being openable by the negative pressure to permit flow there through into the venturi ejector, the vacuum regulated flow control valve, the adjustable valve means, the first one-way flow control valve, and the venturi ejector being connected in a generally vertical arrangement in a manner to produce a continuous upward flow of liquid chemical there through upon application of reduced pressure by the venturi ejector to thereby eliminate gas traps in the vacuum feed system.