Industries – Water use or misuse?
The industrial sector is the second highest user of water in India, consuming about 22% of the total fresh water supply. Industries generally utilise water for fabricating, processing, washing, diluting and cooling (as part of the production process) or sanitation of the manufacturing facility. Despite an increasing demand for water in the industry, water use efficiency in the sector (as in agriculture) is relatively low.
Industrial water use varies depending on the nature of the industry, for instance, the processes of thermal power plants, textile, paper, pulp, iron and steel industries require a substantial amount of water. Notably paper, pulp, textiles industries in India consume more water compared to their peers in the developed countries, indicating thereby that Indian industries are more primitive and inefficient compared to global benchmarks. Most textile mills in India use fresh water (instead of reusing the same water) to wash cloth at every stage of the production process, which is rather wasteful.
The low cost of water is one of the critical reasons for the misuse of water. Generally the low cost of water is driven by significant state subsidies, therefore there is no compulsion for the industries to be prudent or frugal in water use, also most enterprises use fresh water for consumption instead of recycling used water.
Apart from consuming large quantities of water, industries contribute significantly to water pollution. Industrial processes and disposal practices are among the leading causes of water contamination. This is predominantly due to unplanned growth, lack of stringent regulations, use of outdated technologies, lack of capital (including the will) to invest in pollution control equipment etc. Most industries contaminate waterways by discharging their waste into streams and rivers or by run-off or seepage of stored wastes into nearby water bodies. Some industries pollute the aquifer through deep well injection and improper disposal of wastes in ‘surface impoundments’.
Global best practices
Ford Motor Co., Michigan, decreased its per-vehicle water use from 9.8 cubic meters in 2000 to 4.3 cubic meters in 2012 by working with research institutions to devise alternative methods using less water. The Company reduced its water footprint by using ‘dry machining’ i.e. lubricating cutting tools with a little oil rather than large quantities of fluid and water, eliminating one stage of painting and implementing waste-water reuse.
Cascade Tissue Group, a pulp and paper Manufacturer in Quebec, reduced its annual water consumption by 2.6 billion gallons by merely using recycled fibre and process water. The Company recycles the process water nearly at every step i.e. between 10 and 40 recycles before it is sent into the treatment system.
A modern paper mill [in Finland] has reduced the amount of water used per unit by over 90% in the last 20 years by shifting from chemicals to the thermomechanical pulp and installing a biological wastewater treatment plant.
kind of containment pond to safely contain and isolate industrial waste