Scientists at the University of Michigan are producing bio-oil from microalgae in just minutes -- using heat and pressure.
“We make an algae soup,” Savage said. “We heat it to about 300 degrees and keep the water at high enough pressure to keep it liquid as opposed to steam. We cook it for 30 minutes to an hour and we get a crude bio-oil.”More here. The U. Mich. method involves a pyrolytic conversion of algal biomass to biocrude. Other approaches to algal fuels attempt to coax the microalgae into excreting large quantities of bio-oil continuously -- without having to kill or destroy the algae in the process of making biodiesel. Still other approaches aim to gasify algal biomass to syngas, then proceed to make synfuels from the syngas using catalytic syntheses such as Fischer Tropsch.
Using high temperatures and pressure lets the algae react with water and break down, releasing the native oil. Proteins and carbohydrates within the algae also decompose, increasing the fuel yield.
“We’re trying to do what nature does when it creates oil, but we don’t want to wait millions of years,” Savage said. “The hard part is taking the tar that comes out of the pressure cooker and turning it into something you could put in your car, changing the properties so it can flow more easily, and doing it in a way that’s affordable.”
With that in mind, Savage and his colleagues are looking at using catalysts to increase the energy density of the algal fuel. They also hope to reduce its viscosity and cut its sulfur and nitrogen content. _Wired
According to optimistic forecasts at Emerging Markets Algae 2020 PDF, biofuels producers will be producing up to 6 billion gallons per year of algal biofuels by the year 2025.
Japan is looking at converting rice paddies into algal biofuel and aquaculture ponds.
Origin Oil is developing a process to convert wastewater into jet fuel, using algae
As rapidly as algae is capable of growing with a bit of sunlight and CO2, if scientists can tweak the organisms so as to maximise oil production, the algal and microbial fuels industry could go from promise to powerhouse in just a few years. Say, 10 years to significant impact on energy markets, 20 years to providing roughly 30% of liquid fuels.
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