Patent ID: 6099733
Filing Date: 2000-08-08
Classification: B01D

Abstract:
A method of treating raw contaminated water from a water supply comprising:providing a housing having a first port and a second port;providing in the housing at least one separator element arranged within the housing including a water permeable membrane with a characteristic of preventing contaminants in the raw water from passing therethrough, a product water conducting layer arranged adjacent the water permeable membrane for receiving water passing through the water permeable membrane, and a product water carrier duct connected to the water conducting layer for receiving water therefrom;providing a valve for controlling the flow of water through the separator element, the valve comprising:a valve body;a plurality of valve ports in the valve body, each valve port having a channel extending into the valve body for communication of water therethrough;a bore arranged along an axis of the valve body such that each channel extends through the valve body to the bore;a valve member inside and in tight sliding engagement with the bore, said valve member being slidable inside the bore to a plurality of positions for controlling flow of water between selected valve ports;and an activator for selectably moving the valve member between said plurality of positions, thereby controlling the flow of water through the membrane;communicating the raw water from the water supply to one of the first and second ports to pass over the membrane such that product water passes through the membrane leaving contaminants in the raw water to form a concentrated contaminated water stream and passing the stream to the other of the first and second ports;providing a product water outlet port in the housing connected to the carrier duct for receiving product water therefrom;providing the separator element as a thin film composite including the water permeable membrane and the water conducting layer and further including a spacer member on the water permeable membrane and arranging the membrane the spacer member and the water conducting layer in a spiral configuration rolled about an axis so that the spacer member is located between adjacent portions of said water separation membrane and extends between ends of the membrane thereby spacing said portions from one another and to permit the raw water to flow along the separator element in a direction longitudinally of the axis in contact with the membrane;and periodically initiating a sustainable flow in clean water and supplying the clean water to the water conducting layer to pass through the membrane in inverse direction and sustaining the flow through the membrane for a predetermined time period.