A Breakthrough in Algae Harvesting

by Jim Lane (Biofuels Digest) One of the more perplexing problems of the advanced bioeconomy is getting algae out of the water or the water out of the algae. It simply isn’t a problem in traditional, land-based agriculture and most of the nutraceutical applications of algae that were developed early on featured such high price points that it almost didn’t matter what technique was used. A $20,000 price per ton can be forgiving for a lot of crude harvest and extraction ideas.

For algae to become a viable technology for producing foods, feed, chemicals or fuels, where price points drop below $2000 per ton and on down to the $500 per ton levels of fuels today — the attractive aspect of algae is that it grows so darn fast, and the pesky aspect is the harvest cost. Centrifuges work fine but if algae concentrations are 1-2% then they have to move 50-100 tons of water to produce a ton of harvested algae. The energy costs are murderous.

So it comes with a “Big News” sign hung around it’s neck when open-pond algae developer Global Algae Innovations began offering for sale a membrane system that, at scale, could use just 1% of the energy needed to run a centrifuge.

Although GAI is more of an algae owner/operator, they now have the system for sale. It helps the company with cash flow, helps with potential investors who see a “quick win” profitable product, and expands the circle of GAI’s contacts as they have heard from companies from algae remediation to algae producers and wastewater treatment operations.

“Wastewater treatment applications for smaller communities come generally from service providers, and this could work well for them and we’re hearing from them. It gets out bacteria too, and can help pull out nutrition elements, so that these can be re-supplied to the pond and reduce the cost of refertilzing and re-seeding.”

“We’ll be focused on aquaculture first, but we see opportunities for algae in the broader animal feed market, even though the straight up returns in aquaculture are higher.”

The focus for now? “Getting to scale,” said Hazlebeck. “As with everything in the [bioeconomy] sector, it’s not enough to be environmentally advantaged, more sustainable. It has to be economic.”

Right now the company is working at an 8-acre scale in its operating module, and Hazlebeck sees an intermediate scale-up opportunity at 20X that size, around 160 acres. What in land agriculture is known as a quarter section — and of which size there are a lot of available land parcels, we night add, because that was the traditional land grant in the old days of the Homestead Act.

But the full commercial size, Hazlebeck speculates, will be in the low thousands of acres.

CO2? That is expected to come from waste sources, and GAI picked up a $1 million Department of Energy grant last summer “to increase algal biomass yield by deploying an innovative system to absorb carbon dioxide from the flue gas of a nearby power plant.” READ MORE and MORE (National Renewable Energy Laboratory)