Letter to the Editor |30 September 2022

Present gas flare at the landfill - a boon in disguise

Land Fill Gas (LFG) is a normal natural bye product produced when organic matter is decomposed in the landfill.

LFG is usually 50% methane and carbon dioxide (CO2) + organic compounds including sulphur.

Methane is a highly potent greenhouse gas and is considered over 28-35% times more effective than carbon dioxide at trapping heat in the atmosphere as per the studies carried out on climate change.

Municipal Solid Waste (MSW) landfills are the third largest source of human-related methane emissions in the United States accounting to nearly 14.5% of these emissions in the year 2020.

In United States the methane emissions from MSW landfills are equivalent to greenhouse gas (GHG) emissions equivalent to 20.3% million passenger vehicles driven for only one year or the CO2 emissions produced from nearly 1.9 million homes in one year. It is a great energy source lost in the atmosphere if not captured and put to use.

MSW when first deposited in a landfill undergoes an aerobic (with oxygen) decomposition producing methane gas.

After this natural process typically in less than one year, anaerobic methane producing bacteria develop which start decomposing the waste generating large amount of methane gas.

These bacteria decompose landfill waste in four stages. In each stage decomposing process changes the composition of gas produced and at the fourth stage which is the last and final stage, when the activity of bacteria is the highest the methane produced is over 50% along with the 45-50% carbon dioxide.

The landfill in Seychelles is over many years old therefore the bacteria seem to have grown very active and obviously over 50% of methane and similar amount if carbon dioxide is being generated.

Methane being quite inflammable when gets in contact with little ignition or the heat generated in the landfill catches fire hazardous to life and in addition polluting the environment.

The repeated episodes of fire on the MSW in Seychelles clearly shows that a lot of methane is being produced, which can be put to economic use in generation of energy including electricity.

In the United States of America over 50% of methane gas produced from the landfills is used for generation of electricity. This certainly calls for a serious consideration for harvesting this natural energy potential rather than being left untapped. This natural resource could be a good source of revenue.

The recent fire at the landfill is a boon in disguise impressing Seychelles to seriously look at this source. A feasibility study is the immediate need to carry out the economic potential for this natural source, to know the amount of gas volume generated and if found useful a mini project can be developed to produce electricity or put to some other use as potential source by using micro turbines.

Surya Khanna

Jeo Jyoti Foundation

Disclaimer:

The views expressed in this letter are those of the writer and do not necessarily reflect the views of the Seychelles NATION newspaper.