The National Green Tribunal (NGT) has permitted the States, including Karnataka, to use incinerator technology for producing Refuse Derived Fuel (RDF), commonly known as waste-to-energy. This is being seen as a setback to those opposing burning of municipal solid wastes (MSW).
Incineration (जाळून टाकणे)
of waste materials converts the waste into ash, flue gas, and heat. The ash is mostly formed by the inorganic constituents of the waste, and may take the form of solid lumps or particulates carried by the flue gas.
What else has the Tribunal said?
- The Tribunal has said that no waste could be directly put into the incinerators or for power generation, except the specifically permitted.
- Only those wastes that are found unrecyclable after segregation should be put into the incinerators.
- Also, the tribunal emphasized that it was not putting any absolute restriction on Refuse Derived Fuel (RDF) being used as power generation fuel, but first effort should be made for composting of wet waste.
- The States are free to use RDF for generating fuel with due care and caution by framing necessary guidelines.
- The NGT has also directed dividing the State into clusters for locating sufficient number of incinerator plants.
- Authorities are asked to provide maximum space for plants to have large storage and processing area for wastes; ensure green belt of higher density around plants, and adopt new technologies.
- The Central Pollution Control Board and the Ministry of Environment and Forests were directed to prescribe specific guidelines for emissions from incinerators.
- The directions were issued on a case between MSW expert Almitra H. Patel vs. Union of India that was referred to the NGT by the Supreme Court, which since 1996 had issued several directions on management of MSW across the country.
- Based on this case, the Centre had formulated the MSW (Management and Handling) Rules, 2000.
Refuse-derived fuel (RDF):
- Also called as Solid recovered fuel/ specified recovered fuel (SRF) is a fuel produced by shredding and dehydrating solid waste (MSW) with a Waste converter technology.
- RDF consists largely of combustible components of municipal waste such as plastics and biodegradable waste.
- RDF is extracted from municipal solid waste using a mix of mechanical and/or biological treatment methods.
The production of RDF may involve the following steps:
- Bag splitting/Shredding
- Size screening
- Magnetic separation
- Coarse shredding
- Refining separation
Uses of the Fuel:
- RDF can be used in a variety of ways to produce electricity.
- It can be used alongside traditional sources of fuel in coal power plants.
- RDF can be fed into plasma arc gasification modules, pyrolysis plants and where the RDF is capable of being combusted cleanly or in compliance with the Kyoto Protocol, RDF can provide a funding source where unused carbon credits are sold on the open market via a carbon exchange.
- However, the use of municipal waste contracts and the bank ability of these solutions is still a relatively new concept, thus RDF’s financial advantage may be debatable.
- It is a waste treatment technology, which includes the combustion of waste for recovering energy.
- Incineration coupled with high temperature waste treatments are recognized as thermal treatments.
- During the process of incineration, the waste material that is treated is converted in to IBM, gases, particles and heat. These products are later used for generation of electricity.
- The gases, flue gases are first treated for eradication of pollutants before going in to atmosphere.
- Incineration reduces the mass of the waste from 95 to 96%. This reduction depends upon the recovery degree and composition of materials.
- This means that incineration however, does not replace the need for land filling but it reduced the amount to be thrown in it.
Sources: The Hindu, Wiki, MoEF.