UK Companies Join Forces For New Richgro AD Plant In Australia

In the company’s centenary year, the new £3.5M AD plant represents a true cornerstone - not just for the family-owned and run Richgro, but for Australia as a whole.

“Our AD plant sends out a clear message”, says Geoff, “that we can keep our country clean, green and forever the lucky country”, which for many Australians is a phrase that has a very special resonance”.

Prior to the creation of the UK AD & Biogas event, Geoff Richards had visited some waste and recycling trade shows in Europe, realising very early on that with Jandakot’s isolated location, the so-called ‘black box’ package solution was not going to be right for Richgro.

Natural Solutions

“We believed in using food waste and not growing crops to be used as fuel”, added Geoff. “For me it is very important that we find as many natural solutions as possible to the problems that confront the world – and the production of food is one of the biggest. I also wanted to steer well clear of a boxed solution because I needed to know what would be going on inside our AD plant – understand it and be able to operate it in our part of the world”.

Wanting to form a closed loop, with potential to utilise heat and CO2 produced on site, Richgro (with annual electricity costs in excess of £200,000 pa), also wanted to use digestate to blend in with existing Richgro product to improve nutritional and breakdown characteristics, and market the new by-product as a bio-fertiliser.

It was only when he came to ADBA’s show in Birmingham that Geoff said he could meet those at the very heart of AD industry.

“Unlike other exhibitions, it was extremely focused. What was pleasantly surprising when I met Hugh Vaughan from Landia is that I wasn’t really sold to. Some companies want to sell you everything in their product range, even if they know it’s not the best solution, but I was given straight, honest answers to my questions.

He added: “First in Europe and then in Malaysia, we saw how the UK technology could survive in very harsh environments, from snow to extreme heat. I returned to the next UK AD & Biogas and drew up our final list of those companies we believed we could move forward with as long-term trusted suppliers”.

Identified were founder ADBA members Landia (digester pumps and mixers), Edina (gas generators) and Kirk Group (tanks/storage), as well as Uniflare (flare stacks).

“We’ve always taken the pathway of innovation and adapting technology”, continued Geoff. “We needed a far more modern, cost-effective and practical plant that we could easily maintain, which is one of the main reasons we chose Landia’s GasMix. For access it is like an outboard motor – very easy to get at”.

Operational now since January, Richgro has begun generating income from the gate fee for diverting waste from landfill, as well as from the digestate as a biofertiliser by-product.

Around 100 tonnes of food and liquid waste (approximately 35% dry solids) is trucked in each day to the Jandakot plant from supermarkets, abattoirs, fast food chains, breweries and soft drink manufacturers. The facility has a de-packaging system to remove contaminants in order to enhance the digestion process with a pumpable feedstock. This 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 which have Biodome double membrane gasholders on the top, supplied and constructed by Biodome Asia.

Digester mixing is with Landia’s externally-mounted GasMix system, which Richgro brought in not only for it being easy to service, but for its enhanced gas yields and reduction in volatile solids. For pre-treatment, GasMix also reduces viscosity by 30% and is energy-efficient, usually only needing to run for 7-10 minutes in the hour, so the consumed power is just one-sixth of the installed power.

The gas is then cleaned up utilizing a Uniflare flare stack before being turned into energy via an Edina CHP engine with electricity being consumed on site as well as exported to the grid. The heat is used in new on-site greenhouses for helping to grow blueberries (a brand new revenue stream for Richgro), as well as maintaining the plant’s temperature.

“The best feeling in my entire career”

Less than two months since commissioning, the Richgro facility’s processing of mixed commercial and industrial food waste was giving a biogas yield of 138m3/ton. The process capture efficiency was recorded at 91%, with one ton of food waste generating 415kWe and 435kWth from the single onsite CHP, which is running at 100%, producing up to 1.2MW.

Landia’s Hugh Vaughan added: “From my first meeting with Geoff at UK AD & Biogas, to the first drawing – then seeing this immaculate plant up and running on the other side of the world with UK technology is the best feeling in my entire career”.

Geoff Richards concluded: “In our centenary year, creating this first for Australia is something that we are extremely proud of. For the long-term good of our country we feel it is right to diversify, with a robust AD plant built from the very best UK technology that offers a real, joined-up environmental solution”.