Page 241 - Industrial Wastewater Treatment, Recycling and Reuse

CHAPTER 5

Novel Technologies for the

Elimination of Pollutants and

Hazardous Substances in the

Chemical and Pharmaceutical

Industries

2
1
Johannes Leonhauser , Jyoti Pawar , Udo Birkenbeul 3
1
Filtration, Membrane Technology and Waste Water, Bayer Technology Services GmbH, Leverkusen,
Germany
2
Bayer Technology Services, Thane, India
3
Waste water treatment, Bayer Technology Services GmbH, Germany
5.1 INTRODUCTION
Industrial wastewater, especially from chemical and pharmaceutical produc-
tion, often contains substances that need to be treated before being discharged
into a biological treatment plant and subsequent water bodies. Generally, this
can be done close to the production site itself, in selected wastewater streams
before reaching a central treatment plant as shown in Figure 5.1.
Each of these approaches has certain advantages and disadvantages, and
the boundaries between them are fluid. Furthermore, a variety of waste-
water treatment processes exist that can be applied at each stage, making it
a challenging task to choose the best one in economic and ecological terms.
To eliminate micropollutants and hazardous substances, oxidation pro-
cesses such as wet air oxidation, Fenton reaction, or ozone are often applied,
all of which have proven many times to be reliable in practice. At the same
time, new processes are emerging (e.g., electrochemical oxidation with
boron-doped diamond electrodes, UV-oxidation) that in certain cases are
superior (higher efficiency, lower costs) to the established ones. On the other
hand, nondestructive processes such as adsorption or extraction are often
feasible alternatives to oxidation and have to be considered, too. Figure 5.2
shows a (non-exhaustive) overview of processes that can be applied.
To eliminate certain pollutants usually not only one process is appropri-
ate, but a multitude of processes could suffice from a technical point of view.
Therefore, the task is to find the one that fits best in the complex interaction

Industrial Wastewater Treatment, Recycling, and Reuse © 2014 Elsevier Ltd.
All rights reserved. 215