Evaluation of the efficiency natural wastewater treatment systems By Oxidation Ponds -Case Study: Salamieh Plant/Hamma Region-

Dr.Dr. Adel Awad ⁽¹⁾ Dr. Hytham Shaheen⁽²⁾ Ilham Badour^(3)
(1)Professor ,department of environmental engg, Teshreen University, Lattakia, Syria.
⁽²⁾Assoociate professor, department of environmental engg,Teshreen University,Lattakia, Syria.
⁽³⁾postgraduate student, department of environmental engg,Teshreen University,Lattakia, Syria.

Abstract

The constructed natural oxidation ponds for wastewater treatment in Salamieh, Hama region, the only one in Syria, was studied from the physical, chemical and microbiological aspects during the period (february1996-march1998).
The evaluation showed low efficiency of Salamieh plant. The average in best climate condition did not exceed 55% for BOD5, 51% for XOD and 96% for TC & F.C, and this is due to the high organic load of the ponds which varies between (415kg/hectare. Day) in hot period and (448kg/hectare. Day) in cold period. As well the total detention period was not sufficient as it did not exceed 19 days in hot period and 18 days in cold period. Moreover, the efficiency of the plant in bacteriology reduction(FC, TC and Helminthes) was not sufficient so it did not reach the reach the required international bacterial standard for reuse of the treated wastewater in irrigation of unrestricted crops. Also, the climate had its clear affect on the efficiency of biological treatment of the oxidation ponds. Its was clear that the effectiveness of the ponds in the hot period (April-Oct) was better than in the cold period (Nov-March ).
The pilot experimental model of the maturation pond with a detention period of two days gave clear additional improvement about the efficiency of the plant. Said pilot unit had shared in maximum of 58% of BOD5, 35% of COD, 28% of SS, 62% of NH4, 51% of T.C and 86% of F.C thus the treated effluent reached the required standards for its suitability in the unrestricted agricultural irrigation.