Page 320 - Industrial Wastewater Treatment, Recycling and Reuse

294 Industrial Wastewater Treatment, Recycling, and Reuse

iron and steel, and textile subsectors account for approximately 60% of the
water requirements of industry. For future projections, the water require-
ments for each subsector have been separately calculated. The overall water
requirements for 2010, 2025, and 2050 (Table 7.5) have been estimated as
3
37, 67, and 81 km , respectively. It needs to be stated here that until the
1990s, the Indian economy was on a slow growth path (Source: Hydrology
and Water Resources System for India, 2007).

7.2.7.1 Sewage Generation and Existing Treatment Capacity
Some critical field-oriented results are presented to understand the urban
population effect on urban sewage and are as follows:
• Arapidpopulationgrowthintermsofurbantototalpopulationshows2.1%
increase over the decade from 1991 to 2001 (CPCB, November 2005)
(Source: Status of Sewage Treatment in India, CPCB, November 2005).
In a status report on the STPs of Class I cities and Class II towns, it is seen
that out of 269 STPs, 231 are operational and 38 are under construction.
• Pollution of surface water bodies has been realized due to STPs of Class I
cities and Class II towns, necessitating a complete secondary treatment
for recycling and reuse.
Out of total sewage generation of 29,129 MLD from Class I cities and Class
II towns, only 6190 MLD was installed and 22,939 MLD of sewage remains
as a gap for further planning and scope. The pertinent details of the sewage
generation and treatment capacity in Class I cities and Class II towns are
given in Figure 7.2.
A schematic view of the statewise gap in sewage generation and installed
treatment capacity in Class I cities is given in Figure 7.3. The following data
analysis further explains the scope for the gap in capacity to be in the installed
in urban areas.
• Based on the 2001 census population for Class I cities (CUPS/44/1999–
2000), the estimation of sewage generation is presented for the Eastern,
Northern, Central, Western, and Southern regions of the country.
The Western region shows around 8605 MLD of sewage generation,
whereas the other regions show a marginal difference ranging from
4000 to 5000 MLD.
• The installed treatment capacity attained a sewage discharge of 3000–
4000 MLD in the Western region, 3000 MLD in the North, and around
1000 MLD in East, Central, and South.
• Hence it is evident that the Eastern, Central, and Southern regions leave
scope for newer perspectives with modern STPs and to opt for recycling
and reuse schemes for industrial water production.