The Efficiency Comparison of Conventional Activated Sludge and Stabilization Pond Systems in Removal of Cysts and Parasitic Eggs (A case Study: Kermanshah and Gilangharb Wastewater Treatment Plants)

Microbial quality, particularly parasitic characteristics in terms of effluent reuse in agriculture is one of themost important indices.The aimof this study is determination of removal efficiency of Kermanshah wastewater treatment (conventional activated sludge) and Gilangharb wastewater treatment plants (stabilization ponds) for cyst and parasitic eggs.

In this study research samples were taken once in five days from both inlet and outlet of wastewater Plants within a period of five months. The identification and counting of cyst and parasitic eggs were carried out by Mac master slide according to Bailenger method.

The findings shows that mean of parasitic eggs and protozoan cysts in effluent of Kermanshah wastewater treatment plant were 0.99±0.42 and 0.90±0.25 per liter respectively, indeed removal efficiency for parasitic eggs and cysts are %98.42±3 and %97.5±4.5 respectively, but, any parasitic eggs and protozoan cysts in Gilangharb wastewater treatment plant was not observed and removal efficiency of these tow parameters was %100. Ascaris lumbricoides eggs had most number in influent and effluent of both plants.

As results show, removal efficiency for cysts and parasitic eggs in both abovementioned are desirable, and the quality of effluent treatment plant of both the rate of nematode eggs Anglbrg index (number of nematode eggs: 1 " number per liter) is consistent.