University of Michigan engineers lead by Phil Savage, an Arthur F. Thurnau professor and a professor of chemical engineering can "pressure-cook" algae for as little as a minute and transform an unprecedented 65% into bio crude oil.
Savage said, "We're trying to mimic the process in nature that forms crude oil with marine organisms." It's quite a reversal from the natural method thought to take millions of years to make crude oil.
The Michigan team's findings will be presented today, Nov. 1 at the 2012 American Institute of Chemical Engineers Annual Meeting in Pittsburgh.
Savage's organism of choice is the ocean-going green marine micro-alga of the genus Nannochloropsis.
The simplified explanation of the most successful process so far to make their one-minute biocrude is Savage and Julia Faeth, a doctoral student in Savage's lab, fill a steel pipe connector with 1.5 milliliters of wet algae, cap it and plunge it into 1,100-degree Fahrenheit sand. The small volume ensures that the algae is heated through, but with only a minute to warm up, the algae's temperature should have just grazed the 550-degree mark before the team pulls the reactor back out.
Previously, Savage and his team heated the algae for times ranging from 10 to 90 minutes. They saw their best results, with about half of the algae converted to biocrude, after treating it for 10 to 40 minutes at 570 degrees.
Why are the one-minute results so much better? Savage and Faeth won't be sure until they have done more experiments, but they have some ideas.
Savage said, "My guess is that the reactions that produce biocrude are actually must faster than previously thought." Faeth suggests that the fast heating might boost the biocrude by keeping unwanted reactions at bay.
Faeth explains, "For example, the biocrude might decompose into substances that dissolve in water, and the fast heating rates might discourage that reaction."
Related Article: Putin Plays Down Russia's Deadly Dependence on Oil & Gas Revenues
Another point the team makes is that shorter reaction times mean that the reactors don't have to be as large.
"By reducing the reactor volume, the cost of building a biocrude production plant also decreases," Faeth said, though both she and Savage cautioned that they couldn't say for sure whether the new method is faster and cheaper until the process is further developed.
This news is a major breakthrough because current commercial makers of algae-based fuel first dry the algae and then extract the natural oil. But at over $20 per gallon, this fuel production process is a long way from the gas pump.
Savage points out, "Companies know that that approach is not economical, so they are looking at approaches for using wet algae, as are we."
At the very crux of the breakthrough is a major advantage. The wet method doesn't just extract the existing fat from the algae - it also breaks down proteins and carbohydrates. The Michigan minute method did this so successfully that the oil contained about 90 percent of the energy in the original algae. Breakthrough, indeed.
Savage remarks with the obvious, "That result is near the upper bound of what is possible."
It's not a done scientific solution - or not quite yet, anyway.
Related Article: Biofuels Company Teams Up with Enzyme Producer to Try and Kickstart Industry
Before biocrude can be fed into the existing refinery system as petroleum, it needs pre-refining to get rid of the extra oxygen and nitrogen atoms that abound in living things and follow along in the reaction forming the bio oil.
The Savage lab is already developing better methods for this segment of biofuel production, breaking the record with a biocrude that was 97 percent carbon and hydrogen earlier this year. We'll have to wait as a paper on this work is currently under review.
The research, "The Effects of Heating Rate and Reaction Time on Hydrothermal Liquefaction of Microalgae," was funded by the Emerging Frontiers in Research and Innovation program of the National Science Foundation. It looks like money well spent.
The university is already at work pursuing patent protection for the intellectual property, and is seeking commercialization partners to help bring the technology to market. Call quickly.
It's a bit humbling to consider the effort, innovation, intuition and creativity launched to corner a competitive algae fuel product then to have a breakthrough appear that is so simple of a process. The research is very likely to be replicated and see some commercial headway quite soon.
Should the full process show a competitive to crude oil produced price the issue will move to optimal algae mass per area. How far algae and other organisms can get to in making fuels per area is anybody's guess now. What the potential organism list could include is another fascinating question.
Congratulations Professor Savage! Let's hope the process can go to scale very economically. We're wondering if you're working to process algae to natural gas as well?
By. Brian Westenhaus
Brian is the editor of the popular energy technology site New Energy and Fuel. The site’s mission is to inform, stimulate, amuse and abuse the… More
Comments
While the heat process may be academically interesting, in the real world it means that you need a free high volume heat source above 500 degrees and a free bio-available nutrient (phosphorus) source for sustainability, and then you might make a killing with algae biofuels. Neither circumstances seem very probable and totally improbable at the scales required to be a significant part of offsetting our energy deficit.
The heat process seems to be accomplishing two tasks, it ruptures the algae cells releasing the lipids and flares off water vapor increasing the lipid to water ratio of the yield. Since the article doesn't give much information about the final chemical form of the lipids, we don't know how much, if any of the additionally required lipid stabilization might have occurred.
What is clear is the high level of heat energy in-put required to make a lower energy yield product. So bottom line - the process doesn't do anything to offset the other big energy/costs sinks in algae production - growout, harvesting, and de-watering. The heat process's primary contribution (at a very high energy cost) is cell rupturing and final stage drying. The product would still have to be further stabilized to have any value as fuel.
If you had the two critical commodities to make the heat process work - free heat and nutrients, they would be still be more economically attractive applied to more direct higher value processes and products such as direct electrical generation (from the heat) and food (using the nutrients). If anything the high energy input here makes algae biofuel production even less sustainable and less economically feasible.