METHOD AND MEMBRANE INSTALLATION FOR TREATING WATER Russian patent published in 1998 - IPC

FIELD: water treatment. SUBSTANCE: invention relates to membrane separation of solutions and suspensions, in particular, to natural water purification, pretreatment of water before its extended purification, e.g. before its softening; treatment of industrial outflow; separation, cleaning, and concentration of solutions and suspensions of organic and mineral substances. Membrane installation contains: pump to supply initial water, four-pass manifold, a set of separation apparatuses based on hollow-fiber or tubular micro- and ultrafiltration membranes, initial water-supply line, concentrate- discharge line with shutoff valve and diaphragm installed parallel to shutoff valve, and filtrate-discharge line with shutoff valve. Installation is further provided with filtrate-accumulation tank, rinse pump connected through its suction pipe to filtrate- accumulation tank and, through its discharge pipe, to filtrate- discharge line. Method of treating water includes water-filtration stage on membrane installation and installation-regeneration stage. In the filtration stage, set of separation apparatuses receives initial water with no concentrate admixtures, and the latter is discharged through diaphragm in amount not exceeding 6% of produced filtrate. In this case, shutoff valve in the concentrate-discharge line is closed and that in the filtrate-discharge line is opened. In the regeneration stage, rinse pump is switched on in continuous operation mode, shutoff valve in the filtrate-discharge line is closed, that in the concentrate-discharge line is opened and closed, and initial water-supply pump is switched on when shutoff valve in the concentrate-discharge line is opened and switched off simultaneously with its closing. EFFECT: reduced power consumption, improved quality of filtrate, increased productivity of installation and its operation resource. 2 cl, 4 dwg , 4 tbl