Abstract: A closed loop function selector valve which directs high pressure hydraulic fluid to any one of several hydraulic related devices wherein the low pressure drains or returns of all of the devices are directed back to the valve. The valve comprises a hollow valve body having a cylindrical or arcuate inside surface wherein function selector ports are located. A valve drain output port is also located within the valve body. A selector rotor is moveably seated within the valve body having a line pressurized chamber therein which is in flow communication with the pressurized hydraulic line pressure directed into the valve. A chamber exit port is located in the body portion of the selector rotor arranged to be sealably alignable with one of the function selector ports for directing the hydraulic line pressure to any one of the various hydraulic devices connected to a functional selector port. The valve drain output port is always in flow communication with the remaining function selector ports.

Abstract: A purification process for waste water from a textile plant and other manufacturing processes. After preliminary filtering to remove foreign particles, the waste water is treated with a reducing agent, if needed, and the pH adjusted to 8.0-9.5. The waste water is then treated with a flocculating agent. After further treatment in a clarifier, the waste water is passed through a sand filter to remove any residual suspended solids. The pH is adjusted to below about 6.0 and the waste water is then subjected to reverse osmosis.