Algae-to-energy research being con- ducted at the Nelson Mandela Metro- politan University’s institute of chemical technology, InnoVenton, is said to be yielding a bio-crude oil that can be separated into jet fuel and other liquid fuels.
The researchers believe the solution may be also be capable of expanding the life span of coal reserves with a greener coal product.
InnoVenton uses microalgae to convert carbon dioxide from the atmosphere into bio-crude oil and director Professor Ben Zeelie says talks have started with leading international airlines regarding the production of jet fuel from the resource.
“An in-depth analysis of our oil, carried out by the University of Cape Town, revealed that about 30% of the mass of oil we make is perfect for jet fuel,” he says.
In addition to jet fuel, InnoVenton is hoping to produce a significant amount of a so-called ‘bunker 150 oil’ equivalent from the bio-crude oil for power-generation purposes.
“Industries in South Africa burn millions of litres of this fuel in power and heat generators each year,” said Zeelie.
He claims the most significant of InnoVenton’s algae research pertains to the recovery of waste coal in the coal industry.
“Each year, South Africa’s mines produce about 70-million tons of coal waste, enough to run about twenty 1 000 MW power stations. The stockpile of discarded coal in South Africa is estimated at more than 2.5-billion tons, enough to run 20 power stations for more than 30 years, if we can find a way to recover and use this coal waste.”
Zeelie and his team have found that, if coal dust and algae biomass are mixed, the algae collects onto the surface of the coal and binds it with the dust.
The result is a coal-algae agglomerate, which enables the handling of the waste coal by using normal mechanised equipment.
“During this process of binding fine coal particles, the quality of the coal can be improved significantly by separating the minerals, such as common silicates, from carbon components,” says Zeelie.
He adds that studies have shown that, if coal and biomass are burned, they reduce emissions of carbon dioxide, sulphur dioxide and nitrous oxide.
If InnoVenton were to produce sufficient microalgae to recover all the fine coal produced in South Africa each year, an area of about 50 000 ha would be needed to grow the algae and it would be a R93-billion investment with a three-year payback time.
InnoVenton plans to establish a one-hectare technical demonstration photo-bioreactor facility to prove the technical and economic viability of the cultivation system later this year.