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DOE Providing Up To $7M for Research in Stabilizing Fast Pyrolysis Bio-Oils to Support Upgrading to Fuels

The US Department of Energy (DOE) issued a Funding Opportunity Announcement (FOA) for up to $7 million over two years (FY 2008 – 2009) to support advanced research and development in converting non-food based biomass to low-cost bio-oils. Combined with private minimum cost share of 20%, up to $8.75 million would be invested in this research effort.

Recent research has shown that upgrading bio-oils (pyrolysis oil) produced by fast pyrolysis to fungible hydrocarbon fuels—such as gasoline and diesel—by employing conventional petroleum refining techniques, such as hydrotreating and hydrocracking, is a promising pathway for alternate fuels. However, pyrolysis oil has long-term storage stability issues that need to be addressed for this upgrading technology to be commercially viable. In this FOA, DOE is specifically soliciting applications for the development of technology capable of stabilizing the bio-oils.

Under appropriate pyrolysis operating conditions, biomass can be converted to relatively high yields (~70 wt %) of liquids—a mixture of organic compounds (pyrolysis oil) and water. The liquid organics are oxygenated hydrocarbon compounds resulting from the thermal breakdown of lignin, cellulose, and hemicellulose.

Collectively, pyrolysis oil is comprised of a complex mixture of acids, alcohols, aldehydes, esters, ketones, sugars, phenols, furans, and multifunctional compounds such as hydroxyacetaldehyde. The relative amounts of each compound class can vary depending on the biomass feedstock used and the operating conditions employed during pyrolysis.

The specific stability issues relate to the characteristic of the pyrolysis oil viscosity to increase over time during storage. The rate of viscosity change is also exacerbated at elevated storage temperatures and can, under extreme conditions, result in the pyrolysis oil becoming a solid.

Because they contain a large number of oxygenated organic compounds many of which are organic acids (acetic and formic), pyrolysis oils have a relatively high total acid number (TAN) that require storage vessels and processing equipment to be fabricated from expensive corrosion resistant alloys.

Another compounding characteristic of pyrolysis oil is the presence of char particles in the condensed product, normally as a result of the thermal processing when cyclones are used to separate particles from the vapor stream.

During pyrolysis, the mineral matter present in the biomass feed ends up being sequestered in the char. Studies have shown this mineral matter to be uniformly distributed throughout the char particle including the surface. Prior research has also linked the presence of this char, and more importantly the mineral content, as potential catalysts for reactions between the various chemical compounds making up pyrolysis oil.

These characteristics present practical problems in the storage, transport, and processing of pyrolysis oils prior to and during their upgrading to hydrocarbon fuels.

DOE is seeking technical approaches to producing pyrolysis oil with a stability enabling the resulting pyrolysis oil to be transported and stored, in commercial scale tankage, for at least six months under ambient conditions. Specifically, it is looking for:

  • Reduction of oxygen content within the various organic compounds collectively comprising pyrolysis oil, with a preference toward rejecting the oxygen as an economically optimum balance between carbon oxides and water.

  • Removal of oxygen present as carboxylic acid groups such that the total acid number (TAN) of the pyrolysis oil is dramatically reduced, preferably below 5.

  • Reduction of char content with pyrolysis oil.

Conceptually, it is possible to approach the stability problem in two fundamentally different ways. One approach is to try to influence the chemistry of the molecular fragments de-polymerizing from the biomass substrate during the initial pyrolysis step. The other approach is to manipulate the chemistry of the pyrolysis oil post pyrolysis (except as noted above with reaction with alcohols). Either approach, or even a combination of the two, is acceptable within the parameters of this FOA.

Resources

Comments

Jonas

This is great, because with pyrolysis we can go carbon-negative and save the planet.

Pyrolysis yields biochar, which you can store as inert carbon in agriculturals soils to improve their productivity.

sjc

After 7 years, this is all we have. Somehow the solutions are always just over the horizon and the funding is well short of accelerating it. This group in the White House has done the work that the oil companies put them there to do. It has set us back more than 8 years and we will all have to pay for this for generations to come.

Jim

Funny I thought we voted "this group" in.

tom deplume

The only votes that counted in the 2000 election were the 9 votes of the Supreme Court.

John

How does the DOE come up with a measly 7 mil as the target for such research? Do they roll dice or something to decide the number? And who decides how many dice they roll?

Healthy Breaze

I'm growing very concerned about the math on biofuels.

It just seems unlikely to me that you can pay the energy cost of cooking organic matter into char and oil, and still be carbon neutral, let alone carbon negative. The land use seems incredibly inefficient for the amount of liquid fuels we want to replace. Solar Thermal sounds like a much more efficient way to power vehicles, end-to-end, assuming we can get the batteries (technology and raw materils given how scarce lithium may be).

Anybody seen any good math on net energy produced by pyrolisis?

Lucas

SIC - Great minds work alike. I had just posted this comment on another chathall.

I watched a repeat of the show, "When the Oil Runs Out" last evening. It was first released in 2006 and was supposed to be what things would be like in 2016.

I was amazed at what had already come to pass. They were saying that oil would soon get to $100 a barrel, etc.

The s**ts going to hit the fan long before 2016.

bushit has sit on his hands, reading, "My Pet Goat" while the country goes down the tubes.

THAT will be his "legacy" !!!

Neil

Healthy Breaze: for a view on lithium supplies check out http://evworld.com/article.cfm?storyid=1434

Aussie

I'm wondering if pyrolysis oil is a dead end. It seems more like expensive vinegar. If only Fischer-Tropsch technology could be miniaturised the same way. Skidmount units could be set up in forests and garbage tips. Pump water from a creek. Charcoal could be scattered back on the nearby soil while tankers haul away finished fuel. Exhaust one location then move on. Unfortunately FT technology seems to be monolithic.

bj

Healthybreeze:
You are asking about the "cold gas efficiency"; for gasification or pyrolysis the efficiencies are over 80% from biomass to output gases (syn-gas), bio-oil and char. The system runs on the 20% not converted to product gas or byproducts such as char...they do not require outside energy.
Go to 'Dynamotive', 'Eprida','BEST Energies', etc. There are over 150 companies marketing gasification sytems and at least a dozen with lower temp pyrolysis.

For example with the Eprida system 40% of the carbon goes to the enhanced char product, 50% to the output gases. The char can be sequestered in the soil as a high value carbon based fertilizer. If carbon credits are granted at $50 per ton of CO2 the carbon is worth $180 per ton sequestered. Diammonium phosphate just went to $1000 per ton, potash is $500 per ton to give you an idea what chem fertilizers are worth.

bj

Healthybreeze:
You are asking about the "cold gas efficiency"; for gasification or pyrolysis the efficiencies are over 80% from biomass to output gases (syn-gas), bio-oil and char. The system runs on the 20% not converted to product gas or byproducts such as char...they do not require outside energy.
Go to 'Dynamotive', 'Eprida','BEST Energies', etc. There are over 150 companies marketing gasification sytems and at least a dozen with lower temp pyrolysis.

For example with the Eprida system 40% of the carbon goes to the enhanced char product, 50% to the output gases. The char can be sequestered in the soil as a high value carbon based fertilizer. If carbon credits are granted at $50 per ton of CO2 the carbon is worth $180 per ton sequestered. Diammonium phosphate just went to $1000 per ton, potash is $500 per ton to give you an idea what chem fertilizers are worth.

sjc

I am projecting peak oil around 2012, if we are not already there. Everyone knows that with enough money you can buy political advisers and ad time to get pretty much anyone elected that you want. Tell them you are for lower taxes and less government and you are in. That is until the debt piles up, the war drags on, the problems go unsolved and things get worse.

Erevesto

Algae
Algae
Algae
If we can just get this one thing to mass production, we can make all the oil we could ever need. There are quite a few rather huge factories sitting empty. You start growing algae on the roof and expand from there.

Al Fin

Thanks, bj, good information. I just don't think the gents are that interested in solving problems. But you have the right idea.

Andrey Levin

Magic properties of biochar to improve fertility of soil is, actually, urban legend.

Char does have small soil-improving effect due to better water retention and aeration properties, but most of well-known positive effect of application of wood ashes is due to fertilizing effect of potassium salts, concentrated in ash due to combustion. Hence the name for long-known bulk chemical “pot_ash”

From Wiki:

“Potash was refined from the ashes of broadleaved trees and produced primarily in the forested areas of Europe, Russia, and North America…Potash production provided late-18th and early-19th century settlers in North America a way to obtain badly needed cash and credit as they cleared their wooded land for crops. To make full use of their land, excess wood, including stumps, needed to be disposed. The easiest way to accomplish this was to burn any wood not needed for fuel or construction. Ashes from hardwood trees could then be used to make lye, which could either be used to make soap or boiled down to produce valuable potash. Hardwood could generate ashes at the rate of 60 to 100 bushels per acre (500 to 900 m³/km²). In 1790, ashes could be sold for $3.25 to $6.25 per acre ($800 to $1500/km²) in rural New York State – nearly the same rate as hiring a laborer to clear the same area… The refined potash was in increasing demand in Europe for use in the production of glass and ceramic goods, and as fertilizer.”

In modern times mineral potassium fertilizer made ash-derived chemicals obsolete.

The only instance where char really has substantial effect on soil fertility is in tropical soils, for example of Amazon, where due to huge rainfall all soil nutrients are bleached by water run-off. Unique combination of area-specific bacteria growing on char particles allows to extract and slowly release into surrounding soil mineral salts adsorbed by char (activated carbon) particles.

Fertility effects of char in all other soils are minuscule.

Aussie

I agree that the case for bio-sequestration via charcoal burial and accelerated plant growth has probably been overstated. If carbon credit peddlers try to use it to make money it could turn sleazy like the rest of their trade. Note that hydrogenation is suggested implying fossil fuel inputs (as in Nextbtl, Bergius CTL) or inadequate renewable hydrogen (as in H2CAR). Either way off-process hydrogen input will rob net energy. Whoever claims success should be thoroughly checked.

bj

Andrey Levin, Aussie:
Do you have more authoritative or better data than what is being generated at Cornell (Lehmann), Iowa State, U of Minnesota, Eprida/Univ of Georgia or in Austrailia by BEST Energies? The U.S. alone has 175 million acres of seriously depleted soils, Iowa has lost a full half of their topsoil...soil degradation is a big problem that bio-char addresses. The two billion tons per year of additional carbon burden in the atmosphere is a big problem that bio-char would also address with a value added by-product of the pyrolysis/gasification systems. Carbon capture storage schemes would cost in the $40 per ton of CO2 range...sequestering carbon as fertilizer would generate income on a local level whether or not you participate in carbon markets.

Aussie

bj
My misgiving about claims for charcoal comes from small scale trials. I suspect that some are transferring charcoal from nearby forests to fields, not just using hay or stover from within the field. As that source of extra charcoal diminishes they will have to travel further to obtain it. The effect is just a one-off timing shift from natural decay processes so that carbon retirement is not all that different in the long run. Pyrolysis is then akin to slash and burn farming but with the recovery of this black goo that nobody knows how to deal with. If this thinking proves correct then charcoal burial for climate mitigation will be largely illusory.

JMartin

Aussie,
Maybe I am missing something, but if you can do a one-off timing shift of 1000 years rather than ten years, at least it buys time. If the soil becomes more productive, then use part of it to grow bamboo or grass to increase char production. When you reach the maximum carrying capacity in the soil, then bury the stuff in the old coal mines, which are no longer needed. If the planet starts to cool, bring it back up and burn it.
I know, it sounds too good and too simple to be true, but let's give it a try. Maybe it will even increase production to feed the world until we can bring population under control.

Paul F. Dietz

As that source of extra charcoal diminishes they will have to travel further to obtain it.
Charcoal is extremely stable in soil, however (lasting possibly thousands of years). Once built up it could be maintained with very little input.

"The only votes that counted in the 2000 election were the 9 votes of the Supreme Court."

Some people watch too much television.

Jonas

Healthybreeze, why do you think an 880% increase in yield as a result of biochar amendments in highly weathered tropical soils is not a good result?

For poor farmers it is the difference between life and death.

Tim

Dear biochar skeptics:

Your critique of biochar is important in this day and age when we are rapidly leafing through the technologies to learn which ones will help us in the end. So, thanks. But here are a few bits that might answer some of your criticisms.

Healthy Breaze, Johannes Lehmann and David Laird have done some quantitative analysis on the potential of biochar to sequester carbon. You can read a few of their papers at:

http://entomology.wisc.edu/~tdmeehan/articles/

Their papers show that biochar might be expected to offset around 10% of human derived CO2. Just like any other biomass project, though, it is important to consider where the material to make biochar comes from. Biochar from municiple, ag, and forestry wastes, algae ponds, diverse perrenial grass communities on marginal land - these things will probably yield a reasonable net energy and net carbon ratio (does anyone know if this analysis has been done?). Destroying pristine carbon sinks and using prime ag land specifically to try and sequester a fraction of the carbon is probably not a great idea, though.

Andrey Levin, you probably already know this, but for others, ash and char are not exactly the same thing. Ash is mineral remains after most carbon is oxidized. Char has the minerals and a lot of the original carbon (20-60%). The mineral portion of char is certainly a benefit to plants, especially in highly leached soils. But the physical structure of the biochar also is good for soil. It increases soil cation exchange capacity, so it helps the soil hold nutrients. It also aerates soil which is important for root respiration, and it aids water movement in the soil, which reduces soil anoxia. Besides benefiting plants, it reduces soil methane and nitrous oxide emmisions, which helps with the greenhouse issue, and it sequesters carbon for 1000+ years. See a nice documentary on the beneifits of biochar in Australia at:

http://www.biochar.org/joomla/index.php?option=com_content&task=blogcategory&id=8&Itemid=10

Aussie, a lot more carbon is sequestered from slash and char than slash and burn because burning sends 95% of the carbon back into the atmosphere and charing puts 20-60% into longterm soil storage.

Hope these bits are useful.

Tim

It just occurred to me that the net energy ratio (as usually calculated) of a "feedtock" must be around 2:1 to break even when sequestering char, assuming that 50% of the potential energy (as reduced carbon) of the feedstock is left behind in the char. Does this make sense? So waste material is a great candidate for biochar because it is already there and takes energy to get rid of it. But doing things like mowing marginal prairie is not so clear. Any thoughts?

sjc

From what I have heard, switch grass only has to be replanted every 10 years or so and can grow on marginal soil with little water and no pesticides. The roots go very deep, so it holds the soil from wind erosion. 30 million acres of it could provide 15 billion gallons of liquid fuel or about 10% of what we use annually.

Gasification plants are designed to produce as little tar as possible. What is produced is used as fuel for the processing plant. I suppose they could design and tune a gasifier to produce more of some products than others. If it is air blown you get one mix, if it is oxygen blown you get another. Varying temperature, pressure, moisture and other variables could change the output to produce more of one product than another.

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