Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Algae

Using locally isolated Chlorella vulgaris in Wastewater Treatment

Alaa Kareem Mohammed; Safaa Abdalrasool Ali; Ibtisam Fareed Ali

Engineering and Technology Journal, 2016, Volume 34, Issue 4, Pages 762-768

In this study locally isolated microalgae (Chlorella vulgaris Bejerinck) was used in wastewater treatment to reduce the pollutant parameters. Three parameters were studied to determine the efficiency of Chlorella vulgaris in reducing COD, BOD and PO4 concentration. Samples of wastewater were taken from a primary station in Al-Rustomiya wastewater treatment station. Three different dilutions of wastewater were tested; 100% waste, 75%waste 25%waste with distilled water. Chemical oxygen demand (COD) values started with 370mg/l, 270mg/l and 200mg/l for samples A, B and C respectively, and it reached after 14 days to 112 mg/l, 88 mg/l, and 120 mg/l. Biochemical oxygen demand (BOD) started with 241mg/l, 200mg/l, and 170 mg/l for samples A, B and C respectively, and it declined to 110 mg/l, 61 mg/l, and 112 mg/l. Finally PO4 started with 39.9 mg/l, 30 mg/l, 21 mg/l and it reached to 17.1mg/l, 8mg/l, 11.2mg/l for samples A, B and C respectively. Sample B showed the best removal values for COD, BOD and PO4 which reached to 88 mg/l, 61 mg/l, and 8 mg/l respectively.

Toxicity of Al-Dura Oil Refinery Wastes Towards Some Freshwater Phytoplanktons

Muwafaq H. M. Lami

Engineering and Technology Journal, 2014, Volume 32, Issue 13, Pages 3185-3199

Petroleum-derived hydrocarbon wastes are one of the most dangerous aquatic environmental pollutants, the production and export of oil are regarded as the main sources of these wastes. Discharging of the oil refinery wastes to the aquatic ecosystems can cause hazardous and harmful effects to its food chain levels especially algae, depending on the released concentrations. The present study experiments were conducted with axenic culture of the green algae Chlorella vulgaris and Scenedesmus dimorphus. Different concentrations of the oil wastes (25, 50, 75 and 100 %) from three selected locations (SO1, SO8 and SO12) at the refinery treatment unit of Al-Dura refinery were prepared.
Decreasing in the algal growth rates associated with increasing in the doubling time of the cells were detected for the both strains when treated with tested concentrations of the oil refinery during the exposure period that took 96 hr. The reduction was clear with C. vulgaris, but it was gradual in the case of S. dimorphus. An accelerating increasing in the algal growth inhibition averages accompanied with increasing in the wastes concentrations as well as time of exposure. The differences in the calculated EC50 values for both strains indicate differences in the toxic effects of the oil wastes in addition to their sensitivity towards such pollutants.