Page 37 - Industrial Wastewater Treatment, Recycling and Reuse

20 Industrial Wastewater Treatment, Recycling, and Reuse

available only in a few cases. If biological treatment is possible, it should be
preferably and effectively applied using modern methods. The current trend
is for reducing plant space requirements along with cost by utilizing hybrid/
new technologies. Process integration is required for fine and specialty che-
micals with high COD and non-biodegradable chemicals. Wastewater as
a source of energy is being increasingly considered. A new strategy is
required involving novel materials, methods, and process integration
options/technology for wastewater treatment encompassing an entire spec-
trum of chemical and allied industries. It may not be out of place at this stage
to emphasize the need to concentrate more on water-intensive industries
rather than scattered efforts in various directions to make major impacts
in this regard.

1.3.1 Hierarchical Approach for Solving Pollution Problems

Strategies for wastewater management or, for that matter, any waste man-
agement problem, can be best addressed through a hierarchical approach,
which involves identification and solution at every stage of operation
(Figure 1.9). At the base is pollution prevention/waste minimization, which
is and should be the most preferred approach. In wastewater treatment, this
can be referred to as ZERO waste: disposal or generation. However, zero

Figure 1.9 Environmental pollution control—hierarchical approach.