The use of methane gas from landfill to fuel electricity generation systems is one solution to the much-needed diversification of energy resources in Southern Africa, says the Institute of Waste Management of Southern Africa (IWMSA).
“We have to take responsibility for finding effective ways to manage and destroy the large volumes of methane being continuously emitted into the atmosphere,” the organisation states.
Landfill gas comprises about 50% methane, which is a colourless, odourless, but highly flammable gas; 40% carbon dioxide; and small quantities of oxygen and nitrogen, as well as over 100 other trade gases, including carbon monoxide and hydrogen sulphide.
The IWMSA says that typical landfill gas, if permitted to accumulate in low-lying or confined spaces, may produce an atmosphere that is both explosive and hazardous to life.
Several regional landfill interest groups that fall under the auspices of the IWMSA enthusiastically support and encourage progress in the field of landfill management and gas extraction methodologies.
IWMSA president Stan Jewaskiewitz says gas can be readily extracted from landfill, provided that proper engineering of the extraction and management system is carried out, and that the landfill is well managed.
The extraction of landfill gas can take place once landfill cells reach capacity, at which point the landfill is covered, extraction equipment and collection pipe networks are established and the process of extracting the landfill gas can begin.
In addition, the installation of landfill gas extraction systems can be incorporated in the landfilling process, enabling the extraction of landfill gas much earlier, prior to the completion of individual landfill cells. The extracted landfill gas can be used to fuel gas engines or turbines and generate electricity.
Not only will this have environmental benefits, but it could also potentially create employment opportunities.