Supercritical fluids have been part of the biofuels technology mix for a long time. we’ve seen them researched for producing algal biofuels without dewatering, as a superior corn oil extraction system. Back in 2008, a team from Saskachewan and India signed a research deal using supercritical CO2 to extract fermentable sugars from biomass.

What is supercritical, anyway?

As everyone knows, above 100 degrees C, water changes from a liquid phase to a gas phase. We’ve seen some uses of steam reforming – such as this REII project – as a biomass pre-treatment technology.

You can change that temperature boundary by changing the pressure – low pressure lowers the boiling point (that’s why there’s no water left on Mars – it boiled away in the thin atmosphere), while increasing the pressure maintains a liquid phase at higher than boiling point.

But there’s another boundary, right around 374 degrees C of temperature and 218 atmospheres of pressure. At that point, the boundary between liquid and gaseous phase water disappears, and what you have is a supercritical fluid.

Why is it important?

Researchers have found a number of catalyst-like uses for supercritical fluids. But, for biofuels, the most important development to date appears to be the work at Ignite Energy, which is using supercritical water to depolymerize biomass and brown coal.

What Ignite Energy has to say

“Ignite Energy Resources uses its proprietary Super Critical Water (SCW) reactor to convert low-valued feedstocks into high-valued oil and coal products. Super Critical Water in our reactor attacks organic polymers, cutting them directly into highly desirable energy products. Ignite believes this is the only comparable SCW continuous flow reactor in the world, producing clean oils and solid products from both ancient Biomass (coal) and modern Biomass (plant).

“The biggest challenge for conventional producers of biomass fuels is to remove water from the material. It is the 50% plus water content that limits the energy density and subsequently the energy value of most Biomass materials. Reducing the energy density, while maintaining a minimal carbon footprint, is also a major challenge.

“Surprisingly, the solution to both challenges is water. Ignite’s process acts simultaneously as a strong acid and strong base to attack organic polymers and convert biomass directly into high-valued oils and solid products.

The emissions claim

Ignite’s “4th State Process,” they say, creates 60% less CO2 than the most widely available coal to liquids technology and can generate clean fuels from biomass that are carbon negative.

Well, that’s news.

Is it pyrolysis?

Well, no, although in some ways the impact is similar, in that you get a lot of oil as a product of the process. No methane, no biochar

The yields?

According to Ignite, the product can substitute for conventional crude oil across the whole product spectrum, and produces 80000 tonnes per year – 550 barrels per day, in its full-scale design. 20 percent of the energy is used up by the process itself. From 16 metric tonnes of brown coal, you realize 1 ton of oil.

What’s unique?

The system has more than a magic catalyst and a process for generating supercritical water. Some of the magic is in the design – how Ignite introduces feedstock into and collect oil from the reactor. So there’s engineering magic as well as catalyst.

What else? For those educated in refinery-speak, there are no polyaromatics, and the product can be process in conventional refinery with a pass through bed to remove excess CO at a very modest cost.

What biomass works?

This process is for forestry and agricultural waste, not municipal solid waste – the consistency is not workable for catalyst at present.

The economics

Using $100/ton biomass, the system models out as competitive with $50 oil based on using biomass, $30 using brown coal

The proof to date?

The current pilot processes 100 kilos per hour of pine sawdust feedstock, and has been stable for 18 months.

Status of the development

Currently raising fresh capital for expansion, and construction of a full-scale demonstration. Not too long ago the company tried a TSX-based reverse merger – a$22M deal that collapsed at last minute.

More on Ignite

The Australian-based company has seed-stage international investors; the technology was developed out of Thomas Maschmeyer’s lab at the University of Sydney. The company website is here.

The Digest’s take

A system competitive with $50 oil based on $100 per ton biomass is right in the sweet spot, economically, for biofuels – enough margin there to make the risk-return fairly attractive. About where companies like ZeaChem expect to be, at full scale. In this case, though, we are looking at a drop-in fuel. Very nice. Needs proof at scale, but we sure could use one or two technologies like this one, if it measures up. Biomass aggregation will continue to vex early-stage investors and ventures, but that’s a problem that needs to be addressed, pronto, on a broad scale.