Optimization of the inclined tube-settler and anthracite-sand filter | |
| Author | Nguyen Cong Binh |
| Call Number | AIT Thesis no. 834 |
| Subject(s) | Sewer-pipe Sewage disposal Sewage--Purification--Filtration |
| Note | A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Engineering of the Asian Institute of Technology, Bangkok, Thailand. |
| Publisher | Asian Institute of Technology |
| Abstract | A pilot scale study of the inclined tube-settler and anthracite-sand filter was conducted in an attempt to optimize the performance of these two units. The inclined tube-settler, with tubes 5 cm x 5 cm cross-section, 93 cm in length, was integrated with four filter-columns, 20 cm x 20 cm x 246 cm each, with various depths of sand and anthracite coal. By changing the angle of inclination with different loading rates, in the turbidity range 58-120 JTU of raw water, it was found that the tube settlers at 40 and 60 degrees of inclination gave better results than those at 50 degrees, with loading rate of 7.5 and 10 m3/hr-m2. In searching for a design parameter for the settler, it was observed that a modified overflow rate incorporating the angle of inclination, length, size and shape of tubes, had a tendency to predict the settler efficiency. In addition, a limit value of 18 cm/min for flow velocity in tube was also re-emphasized. However, it was found that the turbidity range of 21-34 JTU of settler effluent was not suitable for dual-media filter columns although a combination of 80 cm of anthracite with effective size 0.90 mm and 40 cm of sand, effective size 0.48 mm, could sometimes meet the design criteria in terms of headless rate and water quantity produced. It was suggested that reducing loading rate in the tube-settler together with higher filtration rate in the dual-media filter might give a more economical result. Aluminum determinations were also carried out in the treated water during the course of the research. It was found that the absorptiometry method using catechol violet as chromogenic reagent was suitable for the determination of aluminum in the treated water and that the combination of inclined tube-settler and anthracite-sand filtration generally removed all aluminum steamed from the utilization of alum in coagulation process. |
| 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. ;Nguyen Cong Thanh |
| Scholarship Donor(s) | Danish Government |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 1975 |