بررسي تجربي تصفيه پساب هاي آلوده به مواد نفتي با استفاده از فرآيند غشايي اولترافيلتراسيون

چكيده انگليسي :

Experimental Evaluation of Oily Wastewater Treatment by Using Ultrafiltration Membrane Process Mohsen Sadeghian m sadeghian@ce iut ac ir 9 18 2011 Department of Chemical Engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisor Morteza Sadeghi m sadeghi@cc iut ac ir Ahmad Moheb ahmad@cc iut ac irAbstractA large volume of wastewater in the form of oil in water o w emulsions is generated from various industriessuch as petrochemical food transportation and oil refineries There are several techniques to remove oil formwater Typical ones include physical chemical and biological methods There are some advantages anddisadvantages for each of these techniques Membrane separations have been developed greatly over the last 30years and are becoming a promising technology They have high oil removal efficiency low energy consumptionand compact design compared with traditional treatment method Many studies on membrane separation for oilywastewater treatment have been reported particularly in microfiltration MF and ultrafiltration UF withpolymeric and membranes These studies mainly were focused on fouling and methods to enhance flux ormitigate fouling In this research coagulation flocculation process incorporated with membrane separation as anew approach for oily wastewater treatment The coagulation has been done in two ways before membrane andduring membrane filtration inline coagulation The first objective of this study was to investigate the efficacy ofpre coagulation or inline coagulation on oil removal and performance of UF process The second aim of theproject was to optimize operating conditions during coagulation and filtration Optimization performed for threecoagulants alum poly aluminum chloride PAC and chitosan in jar and in filtration equipment Centralcomposite design CCD and response surface methodology RSM were applied to optimize the two mostimportant operating variables coagulant dosage and pH in coagulation In filtration set up the effects of transmembrane pressure cross flow velocity and type of membrane were studied on permeate flux turbidity and CODremoval It is shown that increasing of trans membrane pressure and cross flow velocity increases steadypermeate flux It was observed that turbidity and COD removal efficiency decreases with increasing of transmembrane pressure and cross flow velocity The reason is that oil permeation from oil layer on the surface ofmembrane is higher at higher pressure At higher flow velocity due to higher shear rate oil drops break in smallerdrops which are more permeable through the membrane It was observed that higher oil concentration decreasesflux while removal efficiency is not affected significantly by oil concentration It also observed that coagulationand settling before UF has better results than inline coagulation The reason may be that floc has more time toenlarge In combined process coagulaton filtration of oily water contains 0 5 v v of oil poly aluminumchloride had higher efficiency than aluminum sulfate For this concentration at the optimum conditions theremoval of turbidity and COD were 92 and 89 respectively When coagulant added to the feed of UF processpermeate flux turbidity and COD removal were 51 l m2h 79 and 77 respectively For wastewatercontaining 1 v v using chitosan and poly aluminum chloride for pre treatment step leads to turbidity and CODremoval of 95 and 87 respectively Statistical results demonstrate that all of proposed models possess highconfidence limit and permeate flux of 41 l m2h turbidity removal of 79 and COD elimination of 79 havebeen obtained at optimum conditions Key Words oily wastewater ultrafiltration coagulation optimization

صادقيان، محسن

بررسي تجربي تصفيه پساب هاي آلوده به مواد نفتي با استفاده از فرآيند غشايي اولترافيلتراسيون

ميزان جريان ترواش يافته , ميزان حذف كدورت , ميزان حذف ‍COD