Every city across the world generates thousands of tons of waste every day and is usually dumped in landfills. Accumulation of waste from societies and industries in landfills is a genuine cause of concern as this may cause serious harm to the ecosystem and damage to the environment.
Environmental degradation causes an ecological imbalance that adversely impacts human health as well as poses threats to wildlife.
The environmentalists have also drawn the attention of the governments and public towards fast depleting conventional natural resources of energy. They have strongly advocated for identifying innovative ways for generating energy as conventional energy resources are not going to last forever.
Responding well to the idea of generating energy using waste, many companies like SUEZ have come up with energy from waste projects and production plants.
What is Energy from waste?
Energy from waste, also recognized by its acronym EfW is the treatment of non-recyclable or residual wastes to produce energy from the waste material from residences, industries, agriculture, or any other source which if not managed or treated would become a part of landfills.
EfW has been considered as the best means to convert waste to produce heat and electricity thereby reducing the use of fossil fuel for energy production and mitigating carbon emissions.
Accordingly, efficient waste management is of paramount importance to help the development of a low-carbon society. The waste hierarchy includes:
- Prevention of waste as far as possible Reuse it as far as possible
- Recycle it, if not possible to reuse
- Recovery of energy – from what cannot be recycled, called Residual waste
- Disposal of residual waste
Energy from waste is recovered or derived in various waste plants while ensuring the least emission of harmful gases in various steps.
Steps needed for energy production from waste
Production of energy from waste plants at SUEZ in Australia is done in a step-wise manner that includes:
- Pre-Treatment of waste- a process to segregate waste material that can be recycled so that remaining material may be prepared for recovering energy. The steps include:
- Materials Recovery at a Materials Recovery Facility (MRF)
- Mechanical Biological Treatment (MBT) that includes the process for AD energy conversion
- Mechanical Heat Treatment (MHT) including autoclaving
Following treatment of residual material, it is sent for converting into energy like electricity and heat.
- Conversion Treatment procedures
The processes employed for converting residual waste or RDF/SRF in the form of usable energy i.e., electricity and heat include the use of:
- Incineration
- Thermal Technologies – include:
- Depolymerization
- Gasification
- Plasma Gasification
- Non-Thermal Technologies – such as:
- Anaerobic digestion
- Fermentation
- Mechanical Biological Treatment
Incineration, thermal, or non-thermal treatment processes are essentially employed to release the energy from the waste.
- Conversion of energy recovered into a transportable form of energy like electricity, heat, and fuels
- Emissions clean-up – ensuring waste gases are safe for the environment
It is therefore important to encourage sustainable energy generation using waste as by doing so, you can reap benefits like:
- Reduction of waste going to landfill sites
- Decrease in greenhouse gases
- Lesser use of fossil fuels
- Prevent environmental damage and maintain ecological balance
- Creation of job opportunities
In Australia, we efficiently produce usable and sustainable energy from waste plants at SUEZ using waste diverted from landfills thereby helping maintain the environment and adding substantially to the economy of the country.
