title: Pretreatment of wastewater: optimal coagulant selection using Partial Order Scaling Analysis (POSA).
abstract: Jar-test is a well-known tool for chemical selection for physical-chemical wastewater treatment. Jar test results show the treatment efficiency in terms of suspended matter and organic matter removal. However, in spite of having all these results, coagulant selection is not an easy task because one coagulant can remove efficiently the suspended solids but at the same time increase the conductivity. This makes the final selection of coagulants very dependent on the relative importance assigned to each measured parameter. In this paper, the use of Partial Order Scaling Analysis (POSA) and multi-criteria decision analysis is proposed to help the selection of the coagulant and its concentration in a sequencing batch reactor (SBR). Therefore, starting from the parameters fixed by the jar-test results, these techniques will allow to weight these parameters, according to the judgments of wastewater experts, and to establish priorities among coagulants. An evaluation of two commonly used coagulation/flocculation aids (Alum and Ferric Chloride) was conducted and based on jar tests and POSA model, Ferric Chloride (100 ppm) was the best choice. The results obtained show that POSA and multi-criteria techniques are useful tools to select the optimal chemicals for the physical-technical treatment.
authors.affiliation: Department of Chemical Engineering, Shenkar College of Engineering and Design, 12 Anna Frank street, Ramat Gan 52526, Israel. etzfati@walla.com
authors.forename: Eran
authors.initials: E
authors.lastname: Tzfati
authors.forename: Maya
authors.initials: M
authors.lastname: Sein
authors.forename: Angelika
authors.initials: A
authors.lastname: Rubinov
authors.forename: Adi
authors.initials: A
authors.lastname: Raveh
authors.forename: Amos
authors.initials: A
authors.lastname: Bick
mesh_terms: D000534:Alum Compounds / Q000737:chemistry; D002712:Chlorides / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry; D005427:Flocculation; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: D000534:Alum Compounds; D002712:Chlorides; D005290:Ferric Compounds; D014874:Water Pollutants, Chemical; C024555:ferric chloride