| Author | Nguyen Thi Lien Ha |
| Call Number | AIT Thesis no. EV-93-07 |
| Subject(s) | Electroplating--Waste disposal
|
| Note | A thesis submitted in partial fulfillment of the requirement for the degree of Master of
Science |
| Publisher | Asian Institute of Technology |
| Abstract | This research case study is developed in view of setting up a demonstration project
on °revealing the profitability of clean technology in small scale electroplating unit". It was
conducted in a small scale electroplating shop, located in Bangkok.
A set of simple in-plant control measures such as dragout recovery, spray rinsing
technique, rinse water agitation were implemented. Quantitative data, obtained from the
monitoring of wastewater before and after process modification, have indicated a substantial
reduction both in quantity and strength of wastewater generated. Water consumption was
reduced by approximately 35 % of total rinsing water, which is 18. 7% of total process water
consumption. Average metal concentrations in wastewater was reduced 73% for Cr-, 71.3%
for Ni- and 54.6% for Cu-plating rinse water.
Segregation of different types of wastewater was performed. Experiments were
conducted to investigate the feasibility of treatment and recovery of Cr and Ni using ion
exchange, Cu using electrolysis.
Results from ion exchange study showed that resin Purolite C-100 and A-100 can be
used to remove effectively Ni2+ and Cu2+ ions from the wastewater when the feed
concentration was under 500 mg/l, and chromate ions when feed concentrations do not
exceed 1000 mg Cr6+ 11, respectively. The removal efficiency is dependent on feed flowrate
applied. Ni and Cu can be recovered after additional purification of regenerant effluent. The
N~Cr04 regenerant effluent from A-100 ion exchanger can be converted into H2Cr04
solution, using resin C-105. However it was not found economical.
Electrolytic study revealed the possibility of using a simple electrolytic cell to bring
a Cu metal concentration of 501.6 mg Cu2+ in wastewater down to 52.2 mg/I after 240
minutes, at 5 volt applied (3.06 mA/cm2). Stainless steel plate was not found to be
appropriate anode for electrolysis of Ni-bearing solution.
Recommendations were made for further study on ion exchange and electrolysis, as
well as strategy on the pollution control in small scale electroplating industries in Bangkok. |
| Year | 1993 |
| Type | Thesis |
| 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) | Visvanathan, C.; |
| Examination Committee(s) | Nagarur, Nagendra N.;Reutergardh, Lars Baetz;Murthy, D.V.S.; |
| Scholarship Donor(s) | Canadian International Development Agency (CIDA); |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 1993 |