Page 233 - Industrial Wastewater Treatment, Recycling and Reuse

Advanced Treatment Technology and Strategy 207

electro-oxidation on the surface and also mediated oxidation by other oxi-
dants electrogenerated on the surface from the electrolyte salts. The combi-
nation of these oxidation mechanisms increases the current efficiency of this
technique as compared with other electrochemical technologies.
The arrangement of BDD electrochemical cell is well reported (http://
www.diaccon.de/english/electrode.htm). The principal advantages of the
electrochemical oxidation processes are the following:
1. The process produces less sludge compared to Fenton oxidation processes.
2. Because there is no addition of chemicals, the process does not require
any storage of hazardous chemicals.
3. The process can be operated in batches or continuously.
4. Secondary oxidants generated during the process can improve the overall
oxidation efficiency.
There are certain disadvantages of the electrochemical oxidation process that
can be listed as follows:
1. BDD cells are highly cost prohibitive.
2. The total area required for effective wastewater treatment can make
actual application of BDD in industries very difficult.
3. The process is not easily scalable and thus requires extensive pilot studies.
4. Because the process is driven by current, industries with limited power
availability cannot use this technology.
5. More research is required across different wastewaters to generate a data-
base of organic/molecules that can be destroyed using an electrochemical
process.
A sample of results from laboratory trials conducted on wastewaters
using electrochemical oxidation/BDD electrodes is shown in Figures 4.12
and 4.13.

4.7 IMPLEMENTATION OF ADVANCED OXIDATION
TECHNOLOGIES
Considering the nature of wastewater, it is very difficult to extrapolate an
advanced oxidation technology solution from one industry to another.
And it is sometimes difficult to apply the same technology in two different
wastewater streams of the same industry. A structured approach is required
to identify the right oxidation treatment technology for each industry.
Design thinking can be one such approach. The design thinking process com-
prises seven stages: define, research, ideate, prototype, choose, implement,and learn
(http://en.wikipedia.org/wiki/Design_thinking). Problems can be framed