טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentEyal Sahar
SubjectTreated Waste Water Desalination Using Reverse Osmosis
DepartmentDepartment of Agricultural Engineering
Supervisors Professor Emeritus Zaslavsky Dan (Deceased)
Professor Emeritus Semiat Raphael
Dr. Guetta Rami


Abstract

The amount of sewage in Israel in 2002 is around 560 million cubic meters (MCM) per year .The sewage is the worst pollutant in the land, and it is becoming worse from year to year. Among the problems caused are: ground water pollution; soil destruction; reduced crop yields; badly polluting flood water; spreading human and plant diseases; Traditionally agriculture has served as a mean to treat sewage. New standards that have been suggested in Israel are anachronistic compared with European and American examples. There are 4 different sewage destinations: (1) Agricultural irrigation. (2) Membrane desalination. (3) Dumping sewage water to the environment and to the sea. (4) Dumping the secondary treatment effluent to the rivers; adding it to the water supply system after filtration and chlorination (as in European rivers). Unsuitable conditions help to eliminate alternatives (3) and (4). Against any intuition, an economic real analysis shows that alternative (1) is more expensive than alternative (2) by 1-1.6 dollars per cubic meter, adding up to a sum of more than a half a billion dollars per year.  Alternative (2) has 4 other sub-alternatives which vary in where would be the location of the pre-filtration (MBR/UF) and the desalination (RO). An RO device was built to test the different sub-alternatives. The comparison between sub-alternatives 2 (UF and RO after primary treatment) and sub-alternative 4 (UF and RO after secondary treatment) make us believe, In this point that the best option is alternative 4 due to best quality results.