Recovery and reuse of alum used in removing phosphate from secondary treatment effluent | |
| Author | Perales, Carmelita M. |
| Call Number | AIT Thesis no. EV-79-21 |
| Subject(s) | Sewage--Purification--Activated sludge process Alum |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Abstract | Disposal of alum sludge has been a thorny problem of sanitary engineers today. Alum sludge that resulted from phosphate coagulation is very difficult to handle. It is a gelatinous solid that is hard to dewater. It has been found out to contain fifty per cent or greater water. This investigation was done to determine the feasibility of recovering alum from aluminum phosphate sludge. Two methods of alum recovery, namely; acid and alkali were evaluated. The parameters and variables that affect the initial phosphate coagulation and the variables that affect the recovery process were analyzed. A laboratory experiment was conducted to determine the optimum conditions (i.e., pH, mixing speed, contact time, and initial alum dose) for coagulation and recovery. Further, the secondary effects of coagulation e.g., COD, alkalinity and pH, aside from phosphate reduction were determined. A series of ten cycles of recovery, reuse and recovery process was done to determine the number of times that alum can be economically recycled and reused. Side by side, coagulation using fresh alum was conducted to observe any changes in the characteristics of the floes (i.e., settling and amount of floes) produced using the recovered alum. Cost analysis was done to determine the economic feasibility of alum recovery. |
| Year | 1979 |
| Type | Thesis |
| School | School of Environment, Resources, and Development |
| 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) | Nguyen, Cong Thanh ;Lohani, Bindu N. |
| Examination Committee(s) | Chongrak Polprasert |
| Scholarship Donor(s) | Government of Australia |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1979 |