- The Kochi landfill site around Brahmapuram that caught fire earlier this month was a stark reminder that Indian cities need to be prepared for more such incidents as summer approaches.
- Solid waste management is a major aspect of waste processing in any country.
Why do Landfills catch fire?
- India’s municipalities have been collecting more than 95% of the waste generated in cities but the efficiency of waste-processing is 30-40% at best.
- Indian municipal solid waste consists of about 60% biodegradable material, 25% on-biodegradable material and 15% inert materials, like silt and stone.
- The openly disposed waste includes flammable material like low-quality plastics, which have a relatively higher calorific value.
- In summer, the biodegradable fraction composts much faster, increasing the temperature of the heap to beyond 70-80° C.
- Higher temperature + flammable material = a chance for the landfill to catch fire.
Landfill fires: Surface & Underground fires
- Surface fires: It involves recently buried or uncompacted refuse, situated on or close to the landfill surface in the aerobic decomposition layer. Surface fires generally burn at relatively low temperatures and are characterized by the emission of dense white smoke and the products of incomplete combustion.
- Underground fires: Underground fires in landfills occur deep below the landfill surface and involve materials that are months or years old. The most common cause of underground landfill fires is an increase in the oxygen content of the landfill, which increases bacterial activity and raises temperatures (aerobic decomposition). These so-called “hot spots” can come into contact with pockets of methane gas and result in a fire.
Impacts of Landfill Fires
- Health Risks: Landfill fires pose a particular health risk, as they can release hazardous fumes when these materials and substances ignite.
- Smoke from landfill fires generally contains particulate matter, which can aggravate pre-existing pulmonary conditions or cause respiratory distress. Another serious concern in landfill fires is the emission of dioxins. The term dioxins refers to a group of chemical compounds with similar chemical and biological characteristics that are released into the air during the combustion process.
- Environmental impact: The dense plumes of smoke are the major cause of air pollution. The further release of GHG gasses increases the atmospheric temperature.
- India creates more methane from landfill sites than any other country, according to GHGSat, which monitors emissions via satellites. Methane is the second most abundant greenhouse gas after carbon dioxide – but it is a more potent contributor to the climate crisis because it traps more heat.
- Roadblock to Transportation: Sometimes smoke caused by fire impairs the visibility of commuters.
Landfill Fire prevention
- Fire prevention can reduce property damage, injury, health, and environmental hazards of landfill fires. The cost of prevention is usually much less expensive than the cost of fighting and cleaning up a fire.
- Effective landfill management: Management measures include prohibiting all forms of deliberate burning, thoroughly inspecting and controlling incoming refuse, compacting refuse buried to prevent hot spots from forming, prohibiting smoking onsite, and maintaining good site security.
- Monitoring the emission of methane: If methane levels in or around the landfill become explosive, the landfill operator must take immediate steps to mitigate the danger.
- Converting Landfill Gas to Energy: The conversion of landfill gas to energy turns this landfill byproduct into a marketable resource. The converted gas can be used to generate electricity, heat, or steam.
Solutions to manage landfill fires
- The permanent and essential solution is to ensure cities have a systematic waste-processing system where wet and dry waste are processed separately and their by-products treated accordingly (recycling, soil enrichment, etc.). This will need multiple stakeholders, including municipalities and waste-processing unit operators, to cooperate.
- Clear the piles of waste through bioremediation – i.e. excavate old waste and use automated sieving machines to segregate the flammable refuse-derived fuel (RDF), such as plastics, rags, clothes, etc., from biodegradable material.
- Under the “Clean India” initiative, the efforts are being made to remove these mountains of garbage and convert them into green zones.
- The Global Methane Pledge: A pact to collectively cut global emissions by at least 30% from 2020 levels by 2030.
- India didn’t join because most of its methane emissions come from farming – some 74% from farm animals and paddy fields versus less than 15% from landfill.