Wastewater: an untapped resource for energy recovery

Leveraging municipal wastewater resources into biogas energy provides economic and environmental benefits for community and business.

Understanding the biogas process

Anaerobic Digestion is the biological process that converts wastewater and organic matter into biogas for economic and operational use.

STEP  1   Municipal wastewater is sent to wastewater treatment plant.
STEP  2   The Wastewater Treatment  plant treats the wastewater and produces sewage sludge.
STEP  3   Multi Feedstock Anareobic Digestion and Biogas Storage - Sewer sludge is mixed and anaerobically digested over 2-3 weeks. Agricultural, industrial organic and municipal waste can be added to this process to boost biogas production. Raw biogas is stored in biogas storage holders.
STEP  4   Electricity and Heat Generator and Distribution - Raw biogas is sent to the generator to produce electricity and heat that is then used to power the plant or is distributed to the electricity grid for use by homes and businesses.
STEP  5   Biogas Purification, Liquefaction and Distribution - Raw biogas is dehydrated and impurities removed to produce biomethane. Biomethane is upgraded and 5a) bioCNG is injected into the natural gas network or  5b) undergoes biomethane liquefaction that converts it into bioLNG. BioLNG is transported to a BioLNG station.
STEP  6   BioLNG and BioCNG - Local, green and renewable fuel source available for commercial use that offers significant savings over diesel and petrol.

Biogas benefits

  • Biogas Production Helps Preserve Natural Resources: Increased bioenergy production could help relieve dependency upon natural resources (Australian fossil fuels consumption: Coal 31%, Oil 38%, Natural Gas 24%)
  • Biogas Supports Energy Security: Threats to fuel imports can reduce Australian fuel stocks to a low 20 day supply. Biofuel production relieves fuel stock vulnerability and disruption of essential services.
  • Biogas Combats Climate Change: Biofuels are 90% lower in greenhouse gas emissions compared to other fossil fuels, making it an environmentally viable resource to relieve ozone depletion.
  • Biogas Improves Cost Savings: Biogas cogeneration supports industry energy self-sufficiency, reducing operational energy demand costs by 20% or more.
  • Biogas As A Sustainable Energy Resource: 1m3 of Biogas can generate 9.94Wh of energy, the equivalent of 1.1litre of petrol or 0.5Kg of LPG.


Biogas as a commercial renewable energy

Application by BioType
Waste Water         Food Waste


* Data used throughout this illustration were sourced from a variety of industry case studies, scientific and engineering studies

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© 2017 SUEZ Water Pty Ltd