It almost sounds too good to be true. Grow algae in an open-air pond using saltwater. Then heat it under pressure and, within a matter of minutes, convert the algae into what is effectively crude oil.

That sure beats burying biomass and waiting millions of years for nature to take its course. It also looks good compared with biofuels derived from food crops. The process is perfect for non-arable land, it doesn’t require fresh water, and produces more fuel per hectare than conventional biofuel crops.

Is this ‘green crude’ really the breakthrough in biofuels that it appears to be? “Yes,” says Muradel’s CEO Dr David Lewis. But there is a catch. Since we looked at Muradel last year oil prices have plummeted. So while Muradel’s green crude is energy-positive (only 30-50% of the energy contained in the original feedstock is used in processing) and the ultimate fuels have a lower carbon footprint than fossil oil-derived fuels, it can’t compete with conventional crude at current oil prices. That’s caused Muradel to investigate separate pathways for its two key areas of expertise.

A big drop in the price of oil has created challenges for Muradel | Image:

A tale of two technologies

Muradel’s story is one of two quite different technologies.

The first is all about algae. This involved selecting the right strains, optimising growing conditions, and harvesting it efficiently.

The second technology is hydrothermal liquefaction. Muradel has developed a unique process incorporating pre-treatment and a proprietary Sub-critical Water Reactor (SCWR) in which biomass is heated to 350 degrees Celsius at a pressure of 200 bar (atmospheres) for a few minutes, and hey, presto! out comes green crude oil. This can then be refined into the same fuels we run our cars, trucks and planes on today. No changes to refineries, distribution infrastructure or vehicles are needed. That’s a big advantage over alternative fuels such as hydrogen and existing biofuels.

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Poo to the rescue

Crucially, Muradel’s SCWR is, David says, “feedstock agnostic”. So while the high cost of algal production coupled with low oil prices could have stopped Muradel dead in the water, the Company’s search for alternative feedstocks has in fact opened up the prospects of doing even more environmental good. Just two examples Muradel has explored are old tyres and biosolids – feedstocks that are available at little or no cost.

Biosolids are particularly attractive. A high-energy, truly renewable fuel source, biosolids comprise microorganisms produced from secondary wastewater treatment. Australia produces over 300,000 tonnes of biosolids each year and water utilities already have millions of tonnes in stockpiles, so it might not be too long before we can run our cars on what we flush down the toilet. After it has been through Muradel’s process, of course.

Algae still viable

The low oil price isn’t the end for algae. Muradel has identified oleochemicals, in demand by the chemicals and cosmetics industry, as a primary market. Animal feed is another option, and by-products from the process have the potential to be used as additional feed for the SCWR.

Scaling up

With the University of Adelaide (where David is also an Associate Professor in the School of Chemical Engineering) and Murdoch University as founding shareholders, Muradel has a strong research pedigree. Now it is working to demonstrate that its process is both economically viable and technically robust.

The next step up from the current pilot plant in Whyalla, South Australia, is a 25 megalitre of green crude per annum commercial-scale plant on a five to ten hectare footprint. In addition to the sale of green crude, oleochemicals and by-products, other revenue streams include licensing of Muradel’s intellectual property and equipment manufacture.

While Muradel has developed and patented a number of its innovations other companies are also working on algae as a fuel and improvements to the hydrothermal liquefaction process. Is David concerned by the competition? “No,” he says. “The competition is minimal, it’s a huge market and there is plenty of room for multiple players.”

At the moment it’s all go as Muradel negotiates numerous deals, with the biosolids-derived green crude and algal oleochemicals each representing separate pathways to success.

While hurdles remain, based on progress so far and the very real benefits offered by its processes, it’s no surprise that the world is beating a path to Muradel’s door.

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