Context:

Methane emissions from landfills have an opportunity to capture, recover and use a significant energy resource.

About India’s Methane burden:

• India’s methane emissions in 2016 (excluding land use, land-use change and forestry) were 409 million tonnes of CO2 equivalent, according to India’s Third Biennial Update Report.
• Distribution:
  • There is about 73.96 per cent methane emission of total from the agriculture sector,
  • With around 46 per cent from the waste sector,
  • 62 per cent from the energy sector and
  • 96 per cent from the industrial processes and product use sector.

Greenhouse gas emission from waste:

• Greenhouse gases (GHG) emitted from the waste sector includes carbon dioxide, methane and nitrous oxide, among others.
• Wastewater treatment and discharge (both industrial and domestic) contribute the highest to methane emissions from the waste sector.
• Methane is produced during the decomposition of organic matter in wastewater.
• This can occur in both wastewater treatment plants and after wastewater is discharged into the environment.
• The amount of methane produced depends on several factors, including the type of wastewater, the treatment process and the environmental conditions.
• Open dumpsites and landfills indeed represent significant sources of anthropogenic methane gas emissions.

Concerns related to Methane emission:

• Methane’s global warming potential (GWP), the ability of the gas to trap heat in the atmosphere is 25 times more than carbon dioxide (CO2) and has been second only to CO2 in terms of causing climate change during the industrial era.

• Methane is considered a short-lived climate pollutant, i.e. a short lifespan — of approximately 12 years — in the atmosphere.
• In addition, methane potentially contributes to the formation of ground-level ozone or tropospheric ozone (O3), a hazardous air pollutant and greenhouse gas. Exposure to ozone causes one million premature deaths every year globally.

What are the possible solutions?

• Waste to Biogas: 1 tonne per day (TPD) of segregated biodegradable waste generated in Indian cities has the potential to produce 80 to 100 cubic metres of biogas.
  • The biogas primarily consists of methane (50-75 per cent), carbon dioxide (25-50 per cent) and smaller amounts of nitrogen (2-8 per cent).
• Waste to be subjected to a bio-methanation process in centralised and decentralised facilities with gas collection systems.
• It can be used for various beneficial applications, such as converting biogas into bio-CNG, generating electricity or producing other types of fuel.