Page 28 - Industrial Wastewater Treatment, Recycling and Reuse

Industrial Wastewater Treatment, Recycling, and Reuse: An Overview 11

industry, and hence the dent in profitability (or increase in profitability in a
positive sense) of the industry also varies from case to case. In some cases, the
cost of effluent treatment could be so prohibitive that the sustainability of
the industry itself becomes crucial.
In India, in view of its developing status, industry as well as the agricul-
tural sector are growing and require water, demand for which is also grow-
ing nearly at the same rate. Thus, if industry’s water share is to increase from
the present 6–7% to 18% in 2050, it will be largely at the expense of agri-
cultural water share, which is 80% at present, in general, and >90% in the
Indian states producing water-intensive crops. In view of a huge growth in
population, from the present 1.2 billion to 1.7 billion by 2050, it is
expected that the demand for food grains will be rising substantially, requir-
ing a proportionate rise in agricultural production. This is exactly where
the conflict of interest is likely to occur and is crucial from the point of
view of sustainability. For example, a water-intensive crop such as wheat
3
requires 350–600 m of water per ton of grain, and the sugar cane crop
3
requires 1400–2500 m of water per ton cane. Further, polluted waters
are a threat to agriculture, and a decrease in the order of 40–50% in rice pro-
duction has been reported due to using the polluted waters of the Musi river
for irrigation (Grail, 2009). It is to be noted that a rice crop requires
a 12–18 mm water column in the field for almost half of crop life. The
prolonged period of exposure to polluted waters is also an immense threat
to the food and subsequently to human life. The use of untreated sewage
wastewater, if used for agriculture, is similarly hazardous from a human
health point of view. Conservation of water and wastewater treatment, recy-
cling, and reuse in different formats is the only answer for realizing
sustainability.
Thus, in this context, it becomes necessary to look at the sustainability of
both the environment and industry (Figure 1.7) simultaneously and holisti-
cally. This is where the development and application of various treatment
methodologies become important. In view of the growing concern for
the environment and increasingly stricter government norms worldwide,
it has become necessary for industries to adopt the most suitable technologies
for treating their wastewaters.
For industries and the environment to become sustainable together, it is
necessary that there is a strong commitment at all levels from industry to
government. Further, the environment management system can be decen-
tralized for effective operations. The solution to environmental problems
can be tried from the lowest level in the chain, then taken further up the