Application of electro-chemical process for treatment of arsenic-contaminated water | |
| Author | Anawat Pinisakul |
| Call Number | AIT Diss no.EV-02-03 |
| Subject(s) | Water--Pollution Water--Purification |
| Note | A dissertation submitted in partial fulfil~ment of the reqqirements for the degree of Doctor of Technical Science. Inter-University Program on Environmental Toxicology, Technology and Management, Asian Institute of Technology; Chulabhorn Research Institute and Mahidol University |
| Publisher | Asian Institute of Technology |
| Abstract | This research was conducted to investigate the efficiency, chemical reactions and
mechanisms of arsenic (As) removal from a contaminated water by using the electrochemical
treatment (ECT) process. For a synthetic As-contaminated water, within the
following operating conditions : initial As-concentration of 0.5-5 mg/L, area of electrode
plate/volume ofECT reactor of 0.02 cm2/cm3, 0.1 M KCl, electrical gradient of200 volt/m
and initial pH higher than 3, the laboratory-scale ECT reactors operating in batch mode
were able to reduce As to be within 0.01 mg/L in 15-20 min, making the treated water
suitable for use in shrimp culture. For a contaminated groundwater containing As about
0.135-1.072 mg/L, the batch ECT reactors were effective in reducing the As to be within
0.01 mg/Lin 5 min. The Cr salt was found to yield better As removal efficiencies than the
N03- salt because, chemically, N03- ions interfere with the production of OH- and
Fe(OH)3, the compound mainly responsible for As removal.
A first-order reaction model for As removal, incorporating parameters such as area of
electrode plate/volume of ECT reactor, conductivity and electrical gradient, was developed
which was found feasible in predicting As removal efficiency by the ECT process.
The continuous ECT reactor was found to be equally effective in treating the Ascontaminated
water, but due to the continuous As input, it required longer operation time
than that of the batch operation. However; because of the continuous mixing condition, it
required less power and electi'ode consumptions than those of the batch reactors in
achieving the same As removal efficiency.
The ECT sludge characteristics were analyzed by X-ray fluorescence (XRF) and X-ray
diffractometric (XRD) methods. The results revealed maghemite (Fe203) and angellelite
(Fe |
| Year | 2002 |
| Type | Dissertation |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Energy and Climate Change (Former title: Department of Energy, Environment, and Climate Change (DEECC)) |
| Academic Program/FoS | Environmental Engineering (EV) |
| Chairperson(s) | Chongrak Polprasert; |
| Examination Committee(s) | Preeda Parkpian; Jutamaad Satayavivad; Gupta, Ashim Das;Yamamoto, Kazuo; |
| Scholarship Donor(s) | Post-Graduate Education, Training and Research Program in Environmental Science, Technology and Management under Higher Education Development Project of the Ministry of University Affairs; |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 2002 |