Power Plant Engineering

2. Air Pollution. The 1991 report by the National Environmental Engineering Research Institute
(NEERI), Nagpur documents the amount of pollution that is contributed by different sectors in Delhi:
Pollution by Sector of Origin
1970-71
1980-81
1990-91
1999-2000
2000-2001
(estimated)
(estimated)
Industrial (including thermal
56%
40%
29%
25%
20%
power)
Vehicular
23%
42%
63%
70%
72%
Domestic
21%
18%
8%
5%
8%
In relative terms, the quantum of industrial air pollution has decreased over the years. However,
vehicular pollution has increased rapidly. The drop in share of domestic air pollution is due to the
increased number of LPG connections in Delhi, which have replaced other forms of fuel.
3. Water pollution. The 48-km stretch of the Yamuna River in Delhi is heavily polluted by
domestic and industrial wastewater. The river water upstream of Wazirabad is fit for drinking after it has
been treated, but after the confluence of the Najafgarh drain and 18 other major drains, the water quality
becomes heavily degraded and is unfit even for animal consumption and irrigation.
4. Domestic Wastewater Pollution. The increase in population has resulted in a corresponding
increase in the volume of domestic wastewater that is generated. Sewage treatment capacity is about 344
MGD at present against about 470 MGD wastewater that is generated each day in Delhi. The sewage
treatment capacity is not fully utilized due to malfunctioning of the trunk sewer system.
5. Industrial Wastewater. The industrial wastewater generated in Delhi is about 70 MGD. Al-
though some industrial units have provided facilities to treat wastewater, most small-scale industries do
not have such facilities.

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POWER PLANT ENGINEERING