Introducing the treated water which contains the suspended matter which the harmful matter adsorbs

摘要

PROBLEM TO BE SOLVED: To efficiently decompose/remove harmful materials such as very small amounts of the dioxins in sewage by introducing the ultraviolet ray- irradiated water, to which ozone-containing gas is supplied, into a membrane filtration device so that a part of the ultraviolet ray-irradiated water is membrane-filtrated into treated water and the residue is returned to a raw water tank. ;SOLUTION: Water 1 to be treated is supplied to the raw water tank 2 provided with an ultraviolet irradiating device 3 to irradiate the water 1 with ultraviolet rays. The water 1 irradiated with the ultraviolet rays is withdrawn from the tank 2 by a pump 4 and the ozone-containing gas is supplied from an ozone injecting device 5 to the withdrawn water, which is then introduced into the membrane filtration device 7. In the device 7, a part of the water 1 is filtrated and withdrawn as the treated water 9 and the residue of the water 1 is returned to the tank 2 as circulating water 8. Thereby, the harmful materials such as very small amounts of the dioxins and endocrine-disrupting chemicals contained in the sewage can be efficiently decomposed/removed.;COPYRIGHT: (C)2001,JPO