The GW4 Alliance—a consortium of four leading research universities in the South West of England and Wales—has announced a new project to clean up water from a Cornish tin mine using algae to harvest the precious heavy metals and produce biofuel at the same time.
Researchers from universities in Bath, Bristol, Cardiff and Exeter, in collaboration with Plymouth Marine Laboratory (PML), are now working with the Coal Authority and Veolia to take untreated mine water samples from Wheal Jane tin mine in Cornwall into the laboratory and grow algae in them. The research will explore whether algae is effective in removing materials such as arsenic and cadmium from the mine water.
Researchers will then look to convert the algae into a solid from which it’s expected that precious heavy metals can be extracted and recycled for use in the electronics industry. The remaining solid waste will then be used to make biofuels.
The Wheal Jane tin mine, near Truro in Cornwall, closed in 1992. The Department of Environment, Food and Rural Affairs (Defra) has since that time funded the active mine water treatment scheme to protect the River Fal from pollution. This scheme is managed by the Coal Authority and operated by Veolia.
In August, Nevada-based Algae Systems announced it had developed a way to make algae-based biofuel profitable by transforming raw sewage into fuel and clean drinking water. The company claimed its pilot plant in Alabama can profitably produce diesel fuel from algae by simultaneously making clean water from municipal sewage, utilizing the carbon-heavy residue as fertilizer and generating valuable credits for advanced biofuels. Using a “hydrothermal liquefaction” system, algae and other solids in the sewage are heated to more than 550 degrees Fahrenheit, at 3,000 pounds per square inch, creating a liquid that resembles crude oil from a well. Scientists then add hydrogen to produce diesel fuel.
Algae is also helping to power vehicles in the world's first electric Grand Prix series, with electricity derived from algae as part of an effort to showcase the best in new zero emission technologies. U.K. start-up Aquafuel is supplying generators powered by glycerine, a byproduct of biodiesel that also can be produced from salt-water algae. The fuel is biodegradable, non-toxic and can be used in modified diesel generators to generate power. The compound comes from algae and has zero carbon dioxide (CO2) emissions. When it burns, there is no smoke, smell or even sound.