| Author | Hum, Ke Siong |
| Call Number | AIT Thesis no. 838 |
| Subject(s) | Water, Underground--Thailand--Bangkok
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science of the Asian Institute of Technology, Bangkok, Thailand. |
| Publisher | Asian Institute of Technology |
| Abstract | The level of iron in AIT groundwater was of the order of 0.25 mg/l, which causes the groundwater to be sometimes aesthetically unacceptable.
Thus the primary object of this study was to evaluate feasible alternatives to overcome the iron problem. In the first attempt, a pilot plant consisting of a tray aerator, chemical mixing chamber and upflow solids-contact precipitator was constructed in order to study its
efficiency in iron removal. Firstly, evaluation was made on the
efficiency of the tray aerator. 6-10 cm coke and charcoal were used as packing media and tested for efficiency of oxidizing and removing iron at three different dosing rates, 5, 10 and 15 l/sec-m2. Coke was
found to be a better medium than charcoal and at optimum conditions, it could bring about oxidation of 12% of the iron content and 20% removal at the dosing rate of 51/sec-m2. Accordingly, laboratory jar tests were performed to determine the optimum dosage of chemicals required for iron removal. Alum + NaOC1 and lime + NaOC1 were tried. This result served as a guide in the operation of the pilot plant. With the optimum conditions of aerator and jar tests, at least 60% of the iron was removed, leaving the finished water with iron in the range 0,06-0.09 mg/l, which
had stabilized against iron settlement and coloration for 6 days upon re-chlorination. The second attempt was to study chemical addition for prevention of iron oxidation and settlement. Among the selected chemicals, sodium polyphosphate and silicate seemed to be the best but chemical costs would be high. |
| Year | 1975 |
| Type | Thesis |
| School | Student Research Before 1980 |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Thesis (Year <=1979) |
| Chairperson(s) | Pescod, M.B. ;Yang, Yi Ping |
| Examination Committee(s) | Htun, Maung Nay ;Samorn Muttamara |
| Scholarship Donor(s) | Japanese Government |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 1975 |