What is the need?

• With an ever increasing population and rapid pace of urbanization, the country is facing a huge challenge of waste management. 
• The volume of waste is projected to rise from the present 62 million tonnes to about 150 million tonnes by 2030. 
• Indiscriminate dumping of garbage at the current rate without appropriate scientific treatment, would impose a huge requirement of landfill area per year. 
• This necessitates the importance of scientific solid waste management in today’s context.

Different methods/technologies used for Waste Management

Plasma arc gasification process: 

• It is an option for eco-friendly solid waste management in which large volume reduction of waste up to 95% is possible. 
• The plasma gasification process uses electricity to generate a high temperature plasma arc (above 3000°C) inside the plasma reactor which converts the waste into syngas. 
• The produced syngas when passed through a series of gas purification systems can be used in gas engines for generation of electricity.
• Syngas (Synthesis Gas) is currently made from a mixture of hydrogen and carbon monoxide, and is used to produce a range of commodities, such as fuels, pharmaceuticals, plastics and fertilisers.
• The residual ash can be mixed with cement for preparation of recycled bricks for usage in construction. Thus, it helps in the creation of ‘Wealth from Waste’.

Biomass Waste Disposal

• Biomass waste such as dry leaves, dead branches, dry grass etc. are disposed of by first shredding it to suitable size followed by mixing with the slurry of the biogas digester. 
• This mixture is feedstock for briquette, which is utilized as fuel for cooking. 
• These briquettes are also being utilized in gasifier for production of syngas which can be utilized in gas engine for generation of electricity. 
• The ash produced from burning briquettes is mixed with cement and water in an appropriate proportion for production of bricks which is used for construction work.

Polymer Waste Disposal

• The polymer waste consisting of plastics, sanitary waste etc. is being disposed of through two main processes i.e. pyrolysis and plasma gasification. 
• In the pyrolysis process, the polymer waste is heated to a temperature of 400 – 600°C in an anaerobic environment in presence of suitable catalyst. 

Sanitary Waste Disposal

• The sanitary items including masks, sanitary napkins, diapers etc. are disposed-off utilizing high temperature plasma.

Reference:

1. https://www.pib.gov.in/PressReleasePage.aspx?PRID=1667099