- Case Studies
Edina supplies leading efficiency biogas CHP (combined heat and power) as part of ground breaking AD (anaerobic digestion) project in Australia, generating electricity from waste that otherwise would have been sent to landfill.
The AD plant at Richgro’s composting and manufacturing premises based in Jandakot, Western Australia, is marked as the first of its kind in Australia, and sees a joint collaboration between AD industry advocates Edina, Landia, Biodome Asia (Kirk Group) and Uniflare.
Market leaders in Australia and New Zealand for garden composting products, Richgro wanted to form a closed loop, with potential to utilise heat and CO2 produced on-site. With annual electricity costs in excess of £200,000 pa, Richgro also wanted to use the digestate to blend in with its existing products to improve nutritional and breakdown characteristics, and market the new by-product as a bio-fertiliser.
In search of this technology, Richgro, Managing Director, Geoff Richards first visited companies at the very heart of the UK AD industry at the UK AD & Biogas show in 2013.
Hugh Vaughan, Managing Director, Landia, recalls:
“I thought it was quite novel to have somebody all the way from Australia visit our stand in Birmingham, and I could see straight away that this was a special opportunity for us and our fellow AD members to help make this project happen by working together”.
Biogass Renewables, assisted Richgro in gaining approval for the AD plant from Western Australia’s Department of Environment Regulation, before securing £1.1 million for the project under a debt funding arrangement from the Clean Energy Finance Corporation.
As agreed, Edina, Landia, Biodome Asia, and Uniflare all worked very closely together to co-ordinate delivery and installation for Biogass Renewables.
The AD facility can process more than 35,000 tonnes of commercial and industrial organic waste a year, with the scope to handle 50,000 tonnes, therefore diverting this from landfill.
The facility’s de-packaging system remove contaminants to enhance the digestion process. The feedstock is then put into a blending tank to ensure that the PH balance, proteins fats and other organics are in a good ratio to aid digestion, which is checked by the on-site laboratory before being placed into a buffer tank. The buffer tank acts as a store for the organic matter for the intermittent feeding of the digesters throughout the day.
This organic matter is then fed into two 2,500 cubic meter capacity glass fused to steel digesters, supplied and constructed by Biodome Asia.
The feedstock passed into the primary digester has its own external heating system to maintain the temperature of the digesters, which utilises the co-generated surplus heat from the biogas CHP gas engine to maintain a temperature of approximately 36 degrees Celsius.
Landia supplied its externally-mounted GasMix system used for digester mixing. The system is not only easy to service, but also enhances the gas yield and reduces volatile solids. The gas is then cleaned up utilising a Uniflare flare stack before being turned into energy via Edina Group’s biogas CHP engine.
The MWM TCG 2020 V12 1.2MWe biogas CHP engine was containerised at Edina’s manufacturing facility based in Lisburn, Northern Ireland, before being transported directly to site. Edina commissioned and currently maintains the biogas CHP over a long term maintenance package.
The feedstock used has the capacity to produce up to 2MWe and 2.2MWh and the energy generated is used to power Richgro’s operation and power equipment, with the surplus exported into the Western Australian electricity grid.
Excess heat is channelled into the site’s hothouses, where blueberries are grown, leading to a new revenue stream for the business. The digestate by-product from the plant is used as a raw material in Richgro’s garden products.
Over a 20-year lifespan, the plant expected to save 142,722 tonnes of carbon dioxide emissions.
From our initial discussion with Richgro in 2013, we have been liaising with them and our fellow AD members throughout the project, using our vast experience and expertise within the biogas industry to deliver a support solution befitting for their requirements, long term objectives and strategic goals.”
Tony Fenton, Joint Managing Director, Edina.
Following the success of the installation and performance of the MWM biogas CHP, Richgro have since placed an additional order for a second MWM TCG 2020 V12 biogas CHP engine, due to be commissioned in December 2016.
In the company’s centenary year, the new £3.5M AD plant represents a true cornerstone – not just for Richgro, but for Australia as a whole.
The AD project at Richgro is a ground breaking achievement in a country where AD technology is relatively unknown. The joint collaboration by the UK’s best AD providers, not only sets the benchmark for technological innovation, but also delivers a blueprint for other AD plants to follow across Australia.
This ambitious and forward thinking project has also been highly commended for the ‘Best International Commercial Plant’ industry award at the UK AD & Biogas awards, which took place on the 6th July 2016.