The development of a low-cost membrane system for concentration of domestic sewage | |
| Author | Herath, Kavindya Gayanika |
| Call Number | AIT Caps. Proj. no.CIE-17-37 |
| Subject(s) | Sewage--Treatment Water--Purification--Membrane filtration--Costs |
| Note | A capstone project report submitted in partial fulfillment of the requirements for the degree of Bachelor of Science in Engineering Civil and Infrastructure Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Caps. Proj. ; no. CIE-17-37 |
| Abstract | Many wastewater treatment plants dealing with dilute wastewaters. Especially the diluted sewage are facing number of difficulties in maintaining their system efficiencies and cost overheads. Option with membrane system is not the most cost effective. But it can eliminate the costly stage of primary sedimentation (when dealing with dilute wastewater). Furthermore, it can produce a better quality permeate with improved potential for re-use and also the higher concentrate can be anaerobically digested to recover the energy. This research was conducted in order to concentrate domestic sewage for further treatment by anaerobic treatment. Two types of micro-filtration membrane units (PTFE and PVDF) were chosen to conduct the experiments. For PTFE membrane, amount of COD and TSS (for 10 LMH run) found in the concentration are 1038 ± 268 mg/L and 1465 ± 415 mg/L respectively. Average net energy consumption for concentrate one gram of COD was 1.15 kWh/g COD. Although PTFE membrane was cheap and simple to operate, after few days of operation visible cracks were observed in the membrane surface. Thus it was considered that PTFE membrane system was not suitable for concentrating AIT sewage. For PVDF membrane back flush system was installed to conduct the experimental run. The amount of COD concentration for 10 LMH, 12.5 LMH and 15 LMH fluxes are 3,970 mg/L, 13,333 mg/L and 16,057 mg/L respectively. Furthermore, amount of TSS found in the con centration are 2,840 mg/L, 10,440 mg/L and 21,400 mg/L respectively. Average of net energy consumption for concentrate one gram of COD was 0.02 kWh/g COD. PVDF membrane performance was better than the PTFE membrane. PVDF membrane consumed less energy consumption and it concentrates more in a short period of time. Concentration factor for PVDF membrane was 68 in terms of COD and 177 in terms of TSS. Furthermore, removal efficiency of TSS for PVDF membrane was 100% and for COD, it can be removed up to 85%. Therefore, PVDF membrane system was more suitable to concentrate AIT domestic sewage. |
| Year | 2017 |
| Corresponding Series Added Entry | Asian Institute of Technology. Caps. Proj. ; no. CIE-17-37 |
| Type | Capstone Project |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Civil and Infrastructure Engineering (CIE) |
| Chairperson(s) | Visvanathan, C. |
| Examination Committee(s) | Shrestha, Sangam; |
| Degree | Capstone Project (B.Sc.)-Asian Institute of Technology, 2017 |