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Treatment alternatives for sludge handling in water treatment plant, Bangkok | |
Author | Alam, Md. Ashraful |
Call Number | AIT Thesis no.EV-92-18 |
Subject(s) | Water treatment plants--Thailand--Bangkok Sewage--Purification--Activated sludge process |
Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering |
Publisher | Asian Institute of Technology |
Abstract | This study was aimed to investigate the use of Crossflow Microfiltration (CFMF) to treat the filter backwash wastewater and Vacmun Assisted Sludge Dewate1ing Bed (VASDB) and Filter Press to treat the clarifier sludge generated from Bangkhan Water Treatment Plant of the Metropolitan Water Works Authority (MWA), Thailand. Crossflow Microfiltration (CFMF) is a pressure driven membrane process allowing better permeate flux by shearing action of flow. It can remove most of the suspended solids present in water and wastewater. Periodic backflash was used as a de-clogging technique to minimize the declining flux resulting from membrane surface deposition and intemal pore clogging. In this study, different sets of CFMF experiments were carried out for raw, settled, flocculation with settling of backwash wastewater. Vacuum Assisted Sludge Dewatering Bed (VASD B) and Filter Press were used for dewatering the sludge generated from clarifiers. Capillary Suction Time (CST) test revealed the optimum dosages of Magnafloc LT 26, an anionic polyelectrolyte to be 0.06 %TS. VASDB works with the combined application of gravity and vacuum pressure. The optimum slt1dge2 toading rate found from VASDB expeiiments for vacuum applied conditioned sludge was 15 kg/(m .d). The cake solid content for conditioned sludge with vacuum application, conditioned sludge without vacuum application and non conditioned sludge without vacuum application were 21.9, 10.2 and 3.9 %TS, respectively at the optimum sludge loading rate. Results from pilot scale filter press study showed that a filtration time of 4 hours is necessary to produce a sludge cake containing more than 30 %TS. The filtrates were clear and light yellowish in color having average SS and turbidity of 25 mg/l and 25 NTU, respectively. A cost comparison between VASDB, Sand Drying Beds and Filter Press indicated that VASDB system is a more cost- effective systems. |
Year | 1992 |
Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. EV-92-18 |
Type | Thesis |
School | School of Environment, Resources, and Development (SERD) |
Department | Department of Energy and Climate Change (Former title: Department of Energy, Environment, and Climate Change (DEECC)) |
Academic Program/FoS | Environmental Engineering and Management (EV) |
Chairperson(s) | Samom Muttamara |
Examination Committee(s) | Visvanathan, C.;Mora, J. C.;Sompol Boonthanon |
Scholarship Donor(s) | Canadian International Development Authority (CIDA). |
Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1992 |