A New Twist on Using Wood for Fuel
by Jeremy Elton Jacquot, Los Angeles 
on 05.19.07
The notion of using wood as a source of energy is hardly a new or revolutionary one. At a time when scientists and businesses are increasingly relying on an eclectic and innovative array of alternative energy sources, including palm oil, corn and cellulosic ethanol for fuel and plant sap, apple juice and urine for batteries, turning to a material whose use as an energy source was pioneered by our distant forbears seems odd. Yet, disproving the convention that you can't teach an old dog new tricks, a team of researchers at the University of Georgia has created a new biofuel derived from wood chips that can be mixed in with biodiesel and and petroleum diesel to power conventional engines.
While scientists have long held the ability of deriving oils from wood, they had until now not found a cost-effective way of processing it into a form that could be used in engines. To resolve this issue, researchers at UGA came up with a new chemical process that consists of first burning wood chips and pellets in the absence of oxygen at a high temperature, a process known as pyrolysis, and then condensing the gas that arises as a result of this initial step into a liquid bio-oil that is chemically treated. Approximately 34 percent of the bio-oil derived from the wood can be used to power engines while the charcoal that also arises from the pyrolysis step, known as "carbon char", could potentially be used as fertilizer.
“The exciting thing about our method is that it is very easy to do,” said Tom Adams, director of the UGA Faculty of Engineering outreach service. “We expect to reduce the price of producing fuels from biomass dramatically with this technique.”
Another benefit of this process is that it produces a fuel that is nearly carbon neutral, meaning that it doesn't significantly increase greenhouse gas levels in the atmosphere as long as new trees are planted to replace those used to make the fuel. If the charcoal that is also produced in the process proves viable as a source of fertilizer, Adams argues that the biofuel would actually be carbon negative.
“You’re taking carbon out of the atmosphere when you grow a plant, and if you don’t use all of that carbon and return some of it to the soil in an inert form, you’re actually decreasing the amount of carbon dioxide in the atmosphere,” Adams explained. “We’re optimistic because in most types of soil, carbon char has very beneficial effects on the ecology of the soil, its productivity and its ability to maintain fertility.”
::ScienceDaily: New Biofuel From Trees Developed, ::Researchers improve bio-oil refining, aim for carbon negative production system
See also: ::Ethanol vs. Biodiesel: Just the Facts, ::A Biofuel Nation? Diversa and New Zealand Will Find Out
Follow @TreeHugger on Twitter & get our headlines with @TH_rss!
Thirsty for more? Check out these related articles:
- 5 Reuses for: Watermelon
- Green Glossary: Ingeo
- Green Glossary: Lyocell
- Cooking on a Budget: Use Everything
- Top Green Foods to Fuel Your Workout
- Emeril's Corn and Potato Chowder (Video)
Hello terra preta!
This is potentially even more carbon negative than you indicated Jeremy. We could substitute so much bio-char / terra praeta with the fossil fuel based fertilizers that are currently used in agriculture. So much more carbon could be removed from the atmosphere.
We'd have richer soil for our food and forests to grow. Better water quality. Less soil erosion.
pyrolysis of wood to form gas is very old. Next!
But heating the wood... consumes energy, so what is really gained from this. Unless you can use nuclear / solar or similar power for the initial heating, thus transforming the electric energy into something more store-able.
2 problems with the carbon-negative assertion:
1) burning the wood without using oxygen requires quite a bit of energy to heat... where is that energy coming from?
2) after dumping carbon into the soil, it is eventually going to decompose, either releasing CO2 or methane into the atmosphere... plants absorb carbon from the air, not the soil...
3) where are all these trees that we don't need? It would be much better to burn faster-growing plants than trees to generate biomass for energy needs.
Why the picture of Feline Pine cat litter?
I may be a bit obtuse, but when the hydrogen car concept reared it's head, the fuel was supposed to come from hydrogen derived from water?
Then came the oil execs.
We can make hydrogen from oil!
yeah, let us in on this even if we are the ineficiencies intended to be replaced, becides, we want more mulla!
Now we have suger based ethanol from venezuela at 30 cents a gallon, while we are subsidizing corn toasting that is inefficient. and have a suger embargo that is blocking venezuelan ethanol from hiting this shore.
And canola oil bio diesel?
So the de foresting industry says; let's add wood to bio diesel!
So we can keep cutting trees down!
What is next?
Lets claim running unscrubbed smokestack plumes over wind turbines make them more efficient, and that acid rain cleansed solar panels put out more energy, so we should 'can' more clean air legislation?
Like, there is any left to 'can' in the first place?
Every time we seem to come up with an alternative technology, these who's negative effects such technoly is looking to rectify manage to hijack it.
I'm surprised they have yet to find a way to market lard as an anti cholesterol medication.
I a few thoughts cross the mind of a failed rock musician with no credentials whatever to comment on energy-related issues:
What do we know about the composition of the "carbon char"? Post-pyrolysis, I suspect we'd see a lot of elemental carbon, along with heavier trace elements, primarily metals & metalloids? In the absence of any significant levels of nitrogen, it's not going to help much as a fertilizer. It's good clean bulk (depending on how concentrated & heavy the metals are, but they should be on the lighter end of the scale, eh? Sodium, potassium, et al?). Is there an analysis handy? Enquiring minds want to know.
As noted above, post-pyrolysis, the leftovers are going to either be elemental carbon or very simple (read: stable) compounds. The only things elemental carbon is going to decompose into are protons, neutrons & electrons. I don't see any methane precursors existing post-pyrolysis. The whole idea is like an old prison cartoon - we want to make little ones out of big ones. Since a generic alkane is going to be C(n) H((2n)+2), busting up large organic molecules will ideally use up all pretty much all of the hydrogen, leaving surplus carbon behind. Similar story for CO2 - oxygen will likely go in pyrolysis - in an oxygen deprived atmosphere, I imagine O2 to be in great demand for reactions. I doubt much will be in the "char". I'm entirely willing to stand corrected on this one.
What is the energy balance? How many BTU's are required for pyrolysis relative to the number of BTU's made available? Do we have a net gain or loss of energy?
Hydrogen from water - we have to blame Modern Physic for this and let those black-hearted oil execs off the hook here. The problem there is conservation of energy, touched on above. The energy produced in the formation of a couple of H-O-H bonds is equal to the energy required to separate those same bonds. Given that no energy transfer is 100% efficient, hydrogen from water is a net energy loser. The only way it works is if you have an otherwise difficult to use/store energy source in surplus. Most people suggest making electricity from nuclear energy to then hydrolyze water. There may be a few bugs to work out there...
Here's an unhappy truth - Global Climate Change is not a problem, it is a SYMPTOM! The problem is overpopulation. All living creatures produce waste that is toxic to themselves. When a system is in balance, some other creature can use the first creature's waste as a resource. Humans have become too successful and thrown the system out of balance. We are not going to "tweak" our way out of this one by buying hybrid cars and recycling.
Unfortunately, every modern economy is based on Ponzi-esque continual market expansion. So, population control is a political non-starter. We're heading for a correction of one kind or another. The result will be either no humans or fewer humans. Personally, I'm rooting for the bird flu to take us down to about 3-4 billion. that seems like a nice sustainable number. 6.5 billion ain't working for us.
But then, I don't (officially) know what I'm talking about, so I can be safely ignored.
I a few thoughts cross the mind of a failed rock musician with no credentials whatever to comment on energy-related issues:
What do we know about the composition of the "carbon char"? Post-pyrolysis, I suspect we'd see a lot of elemental carbon, along with heavier trace elements, primarily metals & metalloids? In the absence of any significant levels of nitrogen, it's not going to help much as a fertilizer. It's good clean bulk (depending on how concentrated & heavy the metals are, but they should be on the lighter end of the scale, eh? Sodium, potassium, et al?). Is there an analysis handy? Enquiring minds want to know.
As noted above, post-pyrolysis, the leftovers are going to either be elemental carbon or very simple (read: stable) compounds. The only things elemental carbon is going to decompose into are protons, neutrons & electrons. I don't see any methane precursors existing post-pyrolysis. The whole idea is like an old prison cartoon - we want to make little ones out of big ones. Since a generic alkane is going to be C(n) H((2n)+2), busting up large organic molecules will ideally use up all pretty much all of the hydrogen, leaving surplus carbon behind. Similar story for CO2 - oxygen will likely go in pyrolysis - in an oxygen deprived atmosphere, I imagine O2 to be in great demand for reactions. I doubt much will be in the "char". I'm entirely willing to stand corrected on this one.
What is the energy balance? How many BTU's are required for pyrolysis relative to the number of BTU's made available? Do we have a net gain or loss of energy?
Hydrogen from water - we have to blame Modern Physic for this and let those black-hearted oil execs off the hook here. The problem there is conservation of energy, touched on above. The energy produced in the formation of a couple of H-O-H bonds is equal to the energy required to separate those same bonds. Given that no energy transfer is 100% efficient, hydrogen from water is a net energy loser. The only way it works is if you have an otherwise difficult to use/store energy source in surplus. Most people suggest making electricity from nuclear energy to then hydrolyze water. There may be a few bugs to work out there...
Here's an unhappy truth - Global Climate Change is not a problem, it is a SYMPTOM! The problem is overpopulation. All living creatures produce waste that is toxic to themselves. When a system is in balance, some other creature can use the first creature's waste as a resource. Humans have become too successful and thrown the system out of balance. We are not going to "tweak" our way out of this one by buying hybrid cars and recycling.
Unfortunately, every modern economy is based on Ponzi-esque continual market expansion. So, population control is a political non-starter. We're heading for a correction of one kind or another. The result will be either no humans or fewer humans. Personally, I'm rooting for the bird flu to take us down to about 3-4 billion. that seems like a nice sustainable number. 6.5 billion ain't working for us.
But then, I don't (officially) know what I'm talking about, so I can be safely ignored.