ارزيابي كارايي كيتوسان در حذف جلبك از پساب بركه هاي تثبيت فاضلاب مطالعه موردي بركه تثبيت دانشگاه صنعتي اصفهان

چكيده انگليسي :

Evaluation of Chitosan Performance in Algae Removal from Waste Stabilization Ponds Effluent Case Study IUT waste stabilization pond Kobra Mirzaei k mirzaei@cv iut ac ir June 29 2014 Department of Civil Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language FarsiAmir Taebi amirth@cc iut ac irAbstract This study aimed to eliminate algae from waste stabilization ponds effluent using chitosan through coagulation flocculation sedimentation process The primary criterion to evaluate the efficiency of chitosan usage was turbidityremoval Therefore the samples of waste stabilization pond effluent were tested using chitosan poly aluminumchloride and ferric chloride and the results were compared together Also COD and coliform removal were measuredin some samples coagulated using chitosan All the tests were held in three pH levels of 5 7 5 and natural pH The tests were done in coagulant dose levels of20 40 60 80 mg L for chitosan 50 100 150 mg L for poly aluminum chloride and 100 150 and 200 mg L for ferricchloride Chitosan has a suitable function of turbidity removal making denser and more settleable flocs The highestturbidity removal efficiency of chitosan is 91 in basic pH natural pH of effluent using 80 mg L chitosan and 89 in mutual pH pH level of 7 5 using 20 mg L chitosan while the COD removal efficiency is observed to be 65 and73 and coliform removal efficiency is 97 and 94 respectively Based on the statistical analyses it is suggested touse Quartic model to model chitosan performance in turbidity removal and Quadratic model to model it in CODremoval The optimization results indicate that using 20 mg L chitosan in pH range of 6 6 to 7 turbidity removal couldbe achieved near 100 and COD removal about 77 Poly aluminum chloride functions well just in acidic pH makinglight flocs The highest turbidity removal was observed about 88 in pH 5 using poly aluminum chloride doses of100 and 150 mg L Statistical analyses suggest Quadratic model for turbidity removal predicting the highest efficiencyabout 90 in pH 5 using 140 to 150 mg L poly aluminum chloride Ferric chloride has the best function in mutualpH achieving 88 turbidity removal efficiency using 200 mg L coagulant However the folcs are light and unsettlable changing the effluent color in high doses Based on the optimization results 94 turbidity removal efficiency ispredicted using 200 mg L ferric chloride in pH range of 8 2 to 8 4 Comparing the results less coagulant consumption lack of necessary changes in the pH of effluent producing denser flocs and not changing the effluent color could bepointed out as the advantages of chitosan over poly aluminum chloride and ferric chloride Based on this study chitosan has an adequate performance qualifying the waste stabilization ponds effluent for reuse or discharge receivingwaters Key words algae removal waste stabilization ponds coagulation and flocculation chitosan

ميرزائي ،كبري

ارزيابي كارايي كيتوسان در حذف جلبك از پساب بركه هاي تثبيت فاضلاب مطالعه موردي بركه تثبيت دانشگاه صنعتي اصفهان

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