TY - JOUR
T1 - Role of membrane pore size in tertiary flocculation/adsorption/ultrafiltration treatment of municipal wastewater
AU - Goren, Uri
AU - Aharoni, Avi
AU - Kummel, Mario
AU - Messalem, Rami
AU - Mukmenev, Igor
AU - Brenner, Asher
AU - Gitis, Vitaly
N1 - Funding Information:
This project was supported by Mekorot Water Company Ltd. through contract # 88984201 with Ben-Gurion University. Alfa-Laval Corporation and Dr. Frank Lipnizki are thanked for free membrane samples. The help of Dr. Leonid Kogan with the GC–MS analyses is acknowledged.
PY - 2008/7/1
Y1 - 2008/7/1
N2 - Flocculation, adsorption onto powered activated carbon (PAC), and ultrafiltration (UF), alone and in combination, were tested for tertiary treatment of the secondary effluent from municipal wastewater treatment at the Ashkelon plant (in southern Israel). Encouraging and reliable results of total organic carbon (TOC) of <3 mg/l were achieved with a combination of 130 mg/l FeCl3, 0.6 g/l PAC and UF. The relative contribution of the UF membrane to the reduction of TOC changed with the molecular weight cut-off (MWCO) of the membrane, from a negligible 2.9% for a 100-kDa-MWCO membrane to 17% for 10- and 2-kDa membranes. The latter membranes, however, developed significant fouling, with a 35% drop in flux during first 30 min of the filtration cycle. The flux drop for the 50- and 100-kDa membranes was in the low range of ∼3%. The optimal MWCO interval of 20- to 50-kDa in combination with flocculation/PAC pretreatment gave a significant reduction in organic content with minimal membrane fouling. Detailed GC-MS analysis showed that the combined treatment gave very efficient retention of organic compounds with molecular weights below 800 Da, with the consequent absence of harmful compounds in the tertiary effluent. It was therefore concluded that the recommended flocculation/adsorption protocol constitutes an effective pretreatment for UF and that the obtained tertiary effluent can be used for unrestricted irrigation.
AB - Flocculation, adsorption onto powered activated carbon (PAC), and ultrafiltration (UF), alone and in combination, were tested for tertiary treatment of the secondary effluent from municipal wastewater treatment at the Ashkelon plant (in southern Israel). Encouraging and reliable results of total organic carbon (TOC) of <3 mg/l were achieved with a combination of 130 mg/l FeCl3, 0.6 g/l PAC and UF. The relative contribution of the UF membrane to the reduction of TOC changed with the molecular weight cut-off (MWCO) of the membrane, from a negligible 2.9% for a 100-kDa-MWCO membrane to 17% for 10- and 2-kDa membranes. The latter membranes, however, developed significant fouling, with a 35% drop in flux during first 30 min of the filtration cycle. The flux drop for the 50- and 100-kDa membranes was in the low range of ∼3%. The optimal MWCO interval of 20- to 50-kDa in combination with flocculation/PAC pretreatment gave a significant reduction in organic content with minimal membrane fouling. Detailed GC-MS analysis showed that the combined treatment gave very efficient retention of organic compounds with molecular weights below 800 Da, with the consequent absence of harmful compounds in the tertiary effluent. It was therefore concluded that the recommended flocculation/adsorption protocol constitutes an effective pretreatment for UF and that the obtained tertiary effluent can be used for unrestricted irrigation.
KW - Alum
KW - Ferric chloride
KW - PAC
KW - Pretreatment
KW - Relative removal
KW - UF
UR - http://www.scopus.com/inward/record.url?scp=42949108717&partnerID=8YFLogxK
U2 - 10.1016/j.seppur.2007.10.014
DO - 10.1016/j.seppur.2007.10.014
M3 - Article
AN - SCOPUS:42949108717
SN - 1383-5866
VL - 61
SP - 193
EP - 203
JO - Separation and Purification Technology
JF - Separation and Purification Technology
IS - 2
ER -
