03478cas|a2200409 i 4500 20260817162845.0 050499s1994 th uzm rtt 00| a1eng d .b10087564 AIT Thesis no. EV-94-31 Thayalakumaran, Nagalingam Application of constructed wetlands to the treatment of a heavy metal wastewater Bangkok : Asian Institute of Technology, 1994 99 leaves Thesis ; no. EV-94-31 A thesis submitted in · partial fulfillment of the requirements for the degree of Master of Engineering, School of Environment, Resources & Development Thesis (M.Eng.) - Asian Institute of Technology, 1994 Various industrial activities such as electroplating and metal finishing generate tons of metallic pollutants into the air and water bodies. There are a number of techniques available for the removal of heavy metals from wastewaters. Electroplating industries produce Cr and Ni wastewaters. Because constructed wetlands are cost-effective and energy-efficient, they were used to investigate efficiencies in treating an electroplating wastewater. One pilot-scale and three lab-scale constructed wetland units were constructed at the Environmental Research Station, AIT campus where cattail plants were grown. These constructed wetlands were fed with mixtures of the electroplating wastewater and a domestic wastewater and maintained at a hydraulic retention time of 7 days. Physico-chemical parameters such as pH, SCOD, TSS, DO and influent and effluent heavy metal concentrations were measured at three days interval. Heavy metal removal efficiencies of more than 99 3 were observed in pilot-scale unit even when the influent heavy metal concentrations were 25 mg/l. The heavy metals were removed mainly by precipitation and adsorption. The soil adsorbed more Cr and Ni than the plants. The Cr and Ni ions were strongly held by the root cells showing high concentrations in the roots. Cr was more strongly chelated in the root than Ni. Ni fed wetland plants showed some phytotoxic effects. In the pilot-scale unit, removal efficiencies of SCOD, TSS, TKN were more than 64, 89 and 85 3 respectively. Sewage Purification Heavy metals removal Chongrak Polprasert, Chairperson Samorn Muttamara, Examination Committee Umita, Teruyuki, Examination Committee Government of Finland, Scholarship Donor Asian Institute of Technology. Thesis ; no. EV-94-31 Full-Text http://203.159.5.9/ait-thesis/detail.php?q=B15821 .b10087564 mnait x 241115 2 951012 m a x 0 mnait mnait mnarc 20 40 Barcode : 30050003048039 CREATED : 1994-05-16 RECORD # : i10092961 LPATRON : 1013913 LCHKIN : 2006-03-31 # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 0 TOT CHKOUT : 8 TOT RENEW : 12 Barcode : 30050003604203 CREATED : 1994-05-16 RECORD # : i10092973 LPATRON : 1017232 LCHKIN : 2006-01-21 # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 0 TOT CHKOUT : 12 TOT RENEW : 5 Barcode : 30050160055306 CREATED : 2016-11-05 RECORD # : i12975618 LPATRON : 0 LCHKIN : - # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 0 TOT CHKOUT : 0 TOT RENEW : 0 6530 6530 0 0 0 0 MAIN MAIN mnait 2026-08-17 10.00 0 AIT Thesis no. EV-94-31 30050003048039 2026-08-17 16:28:45 1 2026-08-17 20 0 0 0 0 MAIN MAIN mnait 2026-08-17 10.00 0 AIT Thesis no. EV-94-31 30050003604203 2026-08-17 16:28:45 2 2026-08-17 20 0 0 0 0 MAIN MAIN mnarc 2026-08-17 0 AIT Thesis no. EV-94-31 30050160055306 2026-08-17 16:28:45 2026-08-17 40