| Author | Suvimol Sihirunvong |
| Call Number | AIT Thesis no. AE-92-22 |
| Subject(s) | Water quality
|
| Note | A thesis submitted in partial fulfillment of the
requirement for the degree of Master of Science, School of Environment, Resources and development |
| Publisher | Asian Institute of Technology |
| Abstract | Three experiments were conducted to determine the causes
and consequences of alkalinity and high pH in cement- tank
water. The first experiment was to examine three types of
cement tank treatment (uncoat e d, plastic lining and e pox y
painting tank), filled with two source waters of different
alkalinities and hardness . The uncoated tank fill e d with
vegetable ditch water of low alkalinity and high hardness
resulted in increasing alkalinity and pH and decreased
hardness . On the contrary , uncoated and coated tanks fill e d
with tap water of high alkalinity and low hardness had a
similar trend to decrease alkalinity a nd hardness a nd increase
pH.
The second experiment was conducted to determine the
changes o f alkalinity and pH in response to various alkalinity
and hardness concentration a nd ratio. The drastic fluctuation
occurred in higher levels of alkalinity ( 25 0 and 500 mg
Ca co3
/L). pH fluctuateds lightly in this experiment.
The last experiment was conducted to determine the effect
of various alkalinity and hardness l e v e l s on phytoplankton
growth a nd pH, based on culture of Chlorella's . in modified
Beijerinck medium. The nonlinear corre l a t ion b e tween Chlorella
sp . growth rates and alkalinity levels were highly
significant. Higher levels of alkalinity were more effective
for phytoplankton growth. Like wise , alkalinity levels showed
significant positive effect on pH in the Chlorella culture .
The highest pH obtained from 250 a nd 500 mg Caco3
/L was 9.6 -
10.0 a nd the lowest pH obtained from 20 and 50 mg Caco 3
/L was
decrease d to 5 . 9- 6.1 at the e nd of experiment. Comparison on
the ratios of alkalinity and hardness exhibited that the pH
values changed in two distinct patterns: under equal ratio
(1:1) the pH increase was positively related to the
concentrations of alkalinity and hardness ; under varying
ratios the pH decreased when the ratio was less than 1, and
increased when the ratio was greater than 1. |
| Year | 1992 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Lin, Chang Kwei |
| Examination Committee(s) | Knud-Hansen, C.F. ;Phillips, M.J.
|
| Scholarship Donor(s) | The Government of Netherlands; |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 1992 |