THE EFFECT OF FEED WATER TYPE AND FEED FLOW RATE ON THE PERFORMANCE OF REVERSE OSMOSIS FOR WATER DESALINATION

Abstract

This study was carried out to evaluate the effect of water type and feed flow rate on the performance of reverse osmosis system which was used for water desalination. Two types of water included well water ( 9.6 dS.m-1 ) and drainage water ( 4.25 dS.m-1 ) and three levels of feed flow rate included 4.2, 4.8 and 5.4 m3 h-1 were used in this experiment. Productivity, recovery ratio, specific energy, electrical conductivity and rejection ratio were measured in this experiment. Split plot under complete randomize block design (CRBD) with three replicates was used. It was found that the use of drainage water ( EC = 4.25 dS.m-1) led to obtain higher productivity ( 3.04 m3 h-1 ) , higher recovery ratio (63.91% ) and higher rejection ratio ( 97.42 % ) and led to obtain lower specific energy ( 2.56 kW m-3) and lower electrical conductivity ( 0.109 dS.m-1 ) . It was also found that the use of higher feed flow rate ( 5.4 m3 h-1 ) led to obtain higher productivity ( 2.53 m3h-1) and higher rejection ratio ( 97.06 % ) and led to obtain lower recovery ratio ( 46.98% ) , lower specific energy ( 3.5 kWm-3) and lower electrical conductivity ( 0.218 dS.m-1). It was found that The interaction between lower feed water salinity ( drainage water ) and higher feed flow rate 5.4 dS.m-1 led to obtain the highest productivity 3.21 m3 h-1, lowest specific energy 2.45 kW m-3 , lowest electrical conductivity 0.101 dS.m-1 and highest rejection ratio 97.60 % while the interaction between lower feed water salinity (drainage water ) and lower feed flow rate 4.2 m3 h-1led to highest recovery ratio 68.75 % .