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284 Industrial Wastewater Treatment, Recycling, and Reuse

of India, sewage treatment options, industrial water reuse via recycling,
urban–industry joint venture, and urban–industrial water sustainability in
2030. This presents a major advance in the current preparedness to reach
a long-term sustainability goal of the water sector at large. It also highlights
the cost effectiveness of recycling and reusing urban wastewater for industrial
water production through a few case studies that are in current operation.
This would be useful to practicing engineers in industry, industrialists using
various water-intensive industrial manufacturing and production opera-
tions, pollution control authorities and monitoring engineers, field engi-
neers of the urban and municipal water sector, water regulatory
authorities/boards, and academia, and, as a whole, to the water resources
engineering domain.

7.2 URBAN WATER SECTOR: INDIAN SCENARIO
Sewage wastewater is generated mainly by domestic use such as household
water usage. The generation of such wastewater is highly dependent on peo-
ple and varies significantly from place to place. It is customary to specify the
sewage generation figures on the basis of per capita use of water, which is city/
place of habitation specific predominantly on the basis of habits of people,
water availability, and the water sanitation system. There are major cities
where a large population lives with high levels of per capita water consump-
tion along with systematic sewage systems for the collection and disposal
of sewage wastewaters. In contrast, there are rural areas that have small popu-
lations and a total lack of proper sewage systems. Thus, sewage wastewater
characterization can vary substantially; therefore, this discussion applies only
to general sewage wastewater from a reasonably populated place with a
proper sewage system. Also, it is assumed that the industrial wastewaters
are not mixed with the municipal wastewaters.
Typical characteristics of municipal wastewaters are given in Table 7.1
(http://nptel.iitm.ac.in/courses/105105048/M11_L14.pdf; www.cpcb.
nic.in/newitems/12.pdf—CPCB Report, 2005).
Sewage wastewaters mostly contain organics, dissolved solids, suspended
solids, nitrogen, phosphorus, chlorides/salts, and metals. It is generally
observed that the sewage wastewater pH is in the range of 5.5–8, and its
appearance ranges from cloudy to dark colored. Many times, there is an
appreciable foul odor, which is attributed to the microbial presence in
these wastewaters. In Indian systems, the temperatures vary from place to

place; however, the typical range for most cities is from 15 to 30 C for