Reverse osmosis purifies part of water supply for drinking - while remaining flow is used for less demanding domestic needs

摘要

A supply of water of less than ideal quality is delivered to a purifier (5) holding one or more semi-permeable membranes (6) which with suitable differential pressure pass through the purifier a supply of pure drinking water. Additives such as flavour enhancing CO2 are electronically controlled. Water travelling past, but not through, the membranes is used for domestic purposes such as baths, toilet flushing etc. The purified water is delivered to a storage cotnainer, e.g. an expandible flexible bag (18) inside a rigid casing. If not used in a set period, e.g. 3 days, this stored water is returned to the domestic usage distributor. If the storage cotnainer is full, a counter-pressure is applied near the membrane to halt reverse osmosis and further pure water prodn. USE - Produces pure water, largely free of bacteria, at low cost.