Pilot project to turn biosolids into crude oil

The Australian Renewable Energy Agency (ARENA) is providing up to $4 million in funding to Southern Oil Refining for its pilot project at its refinery near Gladstone, Queensland. The aim of the project? To turn biosolids from sewage into crude oil.

Biosolids are a by-product of the treatment of wastewater. There are currently over 300,000 tonnes of biosolids produced annually through sewage treatment in Australia. Currently these biosolids are managed and treated in a number of ways, including stockpiling.

Now, Southern Oil has partnered with Melbourne Water in an $11.8 million project to build a demonstration-scale hydrothermal liquefaction reactor that will treat up to 1 million biosolids per annum, using a thermochemical conversion process to produce a biocrude. The renewable crude oil will then be upgraded to renewable diesel and potentially renewable jet fuel using Southern Oil Refining’s existing facilities that re-refine waste oils such as transmission and engine oils.

The project will use stockpiled biosolids at Melbourne Water’s wastewater treatment facility at Werribee, Victoria, as well as biosolids from a local sewage treatment facility. It marks the first step to developing biosolid-to-renewable-fuel plants at sewage treatment plants in Australia.

“The hydrothermal liquefaction technology has so much potential to extract value from biosolids and contribute to the renewable fuels market,” said Melbourne Water’s Manager of Treatment and Resources, Jenelle Watson. “Melbourne Water is excited to be partnering with Southern Oil Refining and ARENA to develop hydrothermal liquefaction to a commercial scale.”

ARENA has previously funded Southern Oil Refining to build a first-of-its-kind biocrude and biofuel laboratory and testing facility built on site at Gladstone as part of its advanced biofuel pilot plant. According to the agency’s CEO, Ivor Frischknecht, this latest project offers further opportunities for waste diversion while also helping with Australia’s fuel security.

“A crucial service like wastewater treatment unfortunately produces a significant amount of leftover waste, so we’re particularly excited to see Southern Oil Refining’s project deliver an option to divert biosolids into a recycled, renewable form of energy,” he said.

“This ARENA funding will facilitate Australia’s largest ever demonstration-scale reactor using wastewater treatment biosolids to produce renewable crude oil,” added Tim Rose, Managing Director of Southern Oil Refining. “We will then refine this crude oil into 100% drop in renewable fuels.

“With wastewater treatment stockpiles across the country, this project is entirely scalable and I believe will ultimately lead to the production of hundreds of millions of litres of renewable fuel each year in Australia. This outcome would greatly benefit the environment, be tremendous for the economy while improving Australia’s fuel security.”