Study of Wastewater Treatment by Microalga from the Caspian Sea

In today's modern world, using water by man and different industries produces a large volume of effluents and wastewaters that are a serious threat to humans, environments, and ecosystems. Refining and treatment of the wastewaters are essential. This research investigated the potential of marine microalgae Fischerella sp. in refining nutrients from wastewater. Fischerella sp. was collected from the Caspian sea.Artificial wastewater was prepared by adding different amounts of NaCl (۱, ۵%), CaCl۲ (۳۵, ۱۰۰ mg/L), MgSO۴ (۷۵,۱۵۰ mg/L), NaNO۳ (۵۰, ۲۰۰۰ mg/L) and K۲HPO۴ (۶,۵۰۰mg/L) to BG۱۱۰ medium in ۱۲ runs according to Design expert. The growth and chlorophyll contents in various treatments were measured, and nutrient analysis of the medium was performed on the ۱۰th and ۲۰th days after algal culture. Results showed that maximum growth, chlorophyll and decreasing of Ca۲+, Mg۲+, NO۳- and PO۴۳-content were observed in ۱% NaCl,۳۵ and ۱۰۰ mg/L CaCl۲, ۱۵۰ mg/L MgSO۴, ۲۰۰۰ mg/L NaNO۳ and ۶,۵۰۰ mg/L K۲HPO۴ . The most removing activity was shown in the stationary phase of algal growth. Also, these conditions observed a decrease in TDS, TOC, and COD. It can be concluded that Fischerella sp. is a suitable microalga decreasing nutrients in۱% NaCl and the highest amount of N and P.

Keywords:

Caspian Sea , Chlorophyll , Fischerella sp , growth , Nutrients , Wastewater treatment