Cleaner Technologies (CTs) are the practical application of knowledge, methods and means so as to provide the most rational use of natural resources and energy in order to protect the environment.
Raw materials (including energy) are utilized to produce the desirable useful product or commodity in an industry. Air, water or land pollution is caused by the discharges of waste materials generated in the manufacturing process. The waste materials may contain the unused raw materials land/or any product (s) which is not economically valuable and hence are disposed off to the environment.
There are three broad approaches to cleaner technologies in industrial production, viz.
- Waste minimizing
- End-off-the pipe Cleaning
- Waste Utilization.
1. Waste Minimizing:
Waste minimization is the best of three approaches. This is a preventive approach to pollution control rather than the other two curative approaches, which take care of the pollution after it has been generated- Various means of achieving waste minimization are -raw materials substitution, process changed, better house-keeping, equipment redesign and product reformation. The actual choice depends upon the manufacturing process concerned.
The Advantages of Waste Minimization:
- 1. Less waste to the environment necessarily means better and cleaner environment.
- 2. State of the art technologies are mostly clean technologies. They are more efficient end based on ‘no waste’ or ‘minimum waste’ disposal.
- 3. Better efficiency means low cost of product.
- 4. Waste minimization co-serves raw materials and energy thus helping sustainable utilization of natural resources.
- 5. Products of cleaner industries are preferred internationally. Thus marked requirement promotes clean technologies.
- 6. Clean technology compiles better with environmental regulations.
2. End-off-the-Pipe Cleaning:
The end-of-the-pipe cleaning, though not the best option, is often inescapable. It involves treatment of the effluent or emission before discharge to the environment. In this process the waste is converted to innocuous materials or raw materials, water, energy and byproducts are recovered. A sewage treatment plant converts organic pollutants in sewage to sludge. The end-of-pipe treatment plants are designed to ensure compliance of standards for the effluents and emissions. I
3. Waste Utilization:
The last option of waste utilization involving reclamation and utilization of wastes in other activities is a practical proposition where the quantity of waste generation is high. For example, industrial effluents containing only organic matter but no toxic substance can be used of fertilization of agricultural fields. Thermal Power Plants produce huge quantities of fly ash which can be used for brick making, cement manufacture etc.