DEFLUORIDATION OF ETHIOPIAN RIFT VALLEY REGION WATER USING REVERSE OSMOSIS MEMBRANES

Abstract

f),111/0Ildll//{}11 oj /:'lh/Ol'ulfI Ulft Vailey RegIOn (I:R! HI mil ground "<II.". IIsing reverse osmcms (1<0) mt'rllbww!s was studied. Four RO
memhrO!/t',\', ('.19951'1:", IIU98!'P, LFr: and ESPA t/,,/iI"l"cd hi" IX-;"; (lnd Ilydranaulics were 1II1-eI/igOIt'd jf)'- Ih,' I'e/enllon of fluoride In fluoride
WlI/a .111 jim/" memhranes were observed /0 (1)ee lIre/v n.'lom fluond/!. The fluoride retention of the m;>nlhranes were In the ranges from 94 to 99 % 11"'/ larger Ihon those of chloride. The LFC m.'mbram! wa,~ lested for l::thiopian Rift Valley R,'gIlJ/l IYlW ground wafer, For the same rallge of ji'<,d concenrrarion. the retentIon and permeate
/llioni/e ('/)fJcenlrallOr/ 1$ comparable for raw gruund H'Iller and w"llfieially consliluled fluoride water !/ol>r!l"t'r" Ihe mt'mbrane fouling was serious. ",Ibolll 85 % of Iht' flllx loss was recovered bl IIWlImg Ihe membrane wllh lJNOjsolulion wilh pH : 01 5rfic The Ime causes of the fouling and Ihe hesl In'alnlt'lIl fi)r Ihl;' fouled ml;'mbranl;'"~ reqllll"<"'"/lInh<,r mn'sligalion