[Bioconversion] Grass Pellets

Wed Feb 8 14:53:51 EST 2006

Les

That looks like quite a device you have developed. 

The main advantages of densification are better control on combustion (less
emissions and better efficiencies), ease of feedstock handling, and less
storage requirements. Risk of fire is a major issue with bulk herbaceous
materials. The energy costs associated with densification are modest.

Co-firing wet wood and herbaceous feedstocks might be a promising approach
to use these feedstocks without densification especially in bigger
combustion units. 

It maybe that bulk handling of biomass before densification can help reduce
costs. This is something we would like to see done rather than handle bales
and break bales before densification. Cubing is also cheaper than pelleting
and fits well with commercial boilers.

We have some farmers baling flax straw and burning it. Maybe if you could
high density bale this material it would have even more potential for a unit
such as yours.

Regards

Roger

-----Original Message-----
From: bioconversion-bounces at listserv.repp.org
[mailto:bioconversion-bounces at listserv.repp.org] On Behalf Of Les Blevins
Sent: Tuesday, February 07, 2006 2:09 PM
To: bioconversion at listserv.repp.org
Subject: Re: [Bioconversion] Grass Pellets

Roger & List,

As you said; "Necessity is the mother of invention" and "The grass pellet 
fuel cycle can produce 7 times more net energy gain from an acre of land 
than a corn ethanol fuel cycle."

How about leaving out the pelletizing, cubing or briquetting stage 
altogether? Wouldn't that up the ratio to around eight times more net energy

per acre of land than using the corn ethanol fuel cycle? By eliminating the 
densification a farmer for example can avoid the need for any equipment for 
pelletizing, cubing or briquetting and also avoid the time, space and energy

expense required and farmers are the ones that already have bale making 
capability. Very simple and reliable is sometimes a necessity too.

My company is offering stove and furnace technology that can use whole bales

of fiber fuels. Small square bales or large round bales can be used in our 
system, and there are several ways to automate the system as to loading 
bales into the furnace and achieving automatic ash removal. Slag removal can

also be automated into our system. Other fuels such as tree stumps, waste 
oils, railroad ties and scrap tires can be used in place of bales if needed.

We are not a manufacturing firm so we are looking for companies that want to

get into manufacturing and offering renewable energy systems for the rural, 
farm, commercial, demand side, distributed and On-site energy markets.

Les Blevins
AAEC
785-842-1943
http://www.aaecorp.com/ceo.html

----- Original Message ----- 
From: "Roger Samson" <rsamson at reap-canada.com>
To: "'Tom Miles'" <tmiles at trmiles.com>; "'Clinton M'" 
<clintonmeyer22 at gmail.com>
Cc: <bioconversion at listserv.repp.org>; "'GASIFICATION'" 
<GASIFICATION at listserv.repp.org>
Sent: Monday, February 06, 2006 3:02 PM
Subject: [Bioconversion] Grass Pellets

>
> Tom and all
>
> We have been working on grass pellets and other agrifibres for energy 
> since
> 1991. We have had to wait for the combination of high energy prices and
> advances in combustion technology to get the industry commercial.
>
> Agri-fibre pellets/cubes from the crop milling residue industry are now
> commercially being used in Ontario and Manitoba for applications including
> greenhouse and farm building heating applications and crop drying. In 
> Canada
> we can pellet/cube and burn oat hulls, pin oats, wheat bran, soy hulls, 
> corn
> fibre, flax shives, corn cobs, sunflower hulls and combinations of these
> fuels. Whole plant corn has also been harvested mid winter (after 
> leaching)
> and direct burned without processing by one Canadian geeenhouse producer.
> Corn cobs can also be used without densification. I have been burning late
> fall and overwintered switchgrass in my house for the last two winters in 
> a
> gasifier pellet stove. Canadian farmers will be planting small acreages 
> (the
> most I have heard is 150 acres) of switchgrass and prairie sandreed this
> year as we anticipate that the cheap crop milling residues are soon going 
> to
> be used up. With energy grasses in Eastern Canada, delayed harvesting
> reduces the potassium content to about .35% at the time of late fall
> harvesting and 0.06% if spring harvested. Summer harvested switchgrass is
> like wheat straw about 1.2% potassium. I don't know anyone that can burn
> summer harvested switchgrass or wheat straw over an extended period.
>
> Wheat bran or middlings is a cheap binder for difficult to pellet fuels
> using standard pellet equipment. Switchgrass needs a little more energy to
> pelletize than alfalfa but less than wood fibre. The energy aspects of
> growing grasses and their grinding and densification was recently reviewed
> in our recent paper: "The potential of C4 grasses for developing a global
> Bioheat industry".
> Critical Reviews in Plant Sciences   Publisher:  Taylor & Francis   Issue:
> Volume 24, Number 5-6 / September-December 2005   Pages:  461 - 495
>
http://journalsonline.tandf.co.uk/(4nmnk455r4ngnnnkx1r22u45)/app/home/contri
>
bution.asp?referrer=parent&backto=issue,7,7;journal,2,72;linkingpublicationr
> esults,1:103858,1
>
>
> Necessity is the mother of invention. There are now about a half dozen
> Canadian combustion technology companies selling a range of small to 
> medium
> sized equipment (10 kw to 2 MW) with the ability to efficiently burn
> agri-fibre feedstocks with moderate levels of potassium and chlorine. Some
> equipment has more fuel flexibility than others, you need to shop around.
>
> The grass pellet fuel cycle can produce 7 times more net energy gain from 
> an
> acre of land than a corn ethanol fuel cycle (If George Bush is listening
> this is 7 times faster a way to find energy independence). Even direct
> combustion of grains is getting more popular in Canada this winter. If oil
> can stay around $65/barrel and natural gas at $10 mmbtu, we are going to 
> see
> an enormous industry evolve which will drive up grain prices to about
> $200/tonne. Great for crop producers but it will put an end to the grain
> burning and ethanol industries. The green energy revolution from grasses 
> is
> poised to replace king corn as the energy champion of farmers.
>
> Roger Samson
> Executive Director
> Resource Efficient Agricultural Production (R.E.A.P.) - Canada Box 125
> Centennial Centre CCB13 Ste. Anne de Bellevue, QC, Canada H9X 3V9
> E: rsamson at reap-canada.com
> W: www.reap-canada.com
> "Working to create ecological energy, fibre and food production systems"
>
> -----Original Message-----
> From: stoves-bounces at listserv.repp.org
> [mailto:stoves-bounces at listserv.repp.org] On Behalf Of Tom Miles
> Sent: Friday, February 03, 2006 9:41 PM
> To: 'Clinton M'; stoves at listserv.repp.org
> Cc: bioconversion at listserv.repp.org
> Subject: RE: [Stoves] Grass Pellets
>
>
> At Andrew's suggestion let's migrate this to bioconversion. It's really 
> more
> germane to developed economies but may be of interest to this list as 
> well.
>
> Production of grass pellets.
>
> Specific power consumption for fuel pellets is about 50 kWh/ton plus straw
> preparation and processing which absorbs another 50 kWh/ton. Power, labor
> and extrusion die wear are usually the main costs. A 250 Hp pellet mill 
> will
> produce about 4 tph in straw pellets, 5 tph in wood pellets and up to 7 
> tph
> in recycled paper pellets.
>
> REAP Canada has done quite a bit of work on switchgrass pellets. So Roger
> Samson can give us a clue about production. Their papers can be found on 
> the
> REAP website. The REAP reports show both production and burning equipment.
> http://www.reap-canada.com/bio_and_climate_3_2.htm
> http://www.reap-canada.com/library.htm
>
> Joe King and Richard Nelson at Kansas State University have also studied
> switchgrass pellets.
> http://www.engext.ksu.edu/biomass/_Background.htm
>
> Iowa State University has reported on switchgrass pellets. There is a 
> small
> pellet mill in Southern Iowa that makes them.
>
http://www.agmrc.org/agmrc/commodity/biomass/switchgrass/switchgrassprofile.
> htm
>
> That mill and the Chriton Valley Biomass Project ( 
> http://biomass.ecria.com/
> )got a lot of attention this week after President Bush mentioned 
> switchgrass
> in his State of the Union message. If you saw ABC World News Tonight on
> Wednesday you saw about 10 seconds of our fields and equipment.
>
> Here in Oregon we pelletize seed cleaning from our grass seed production.
> Since they are already sized they are pretty easy to pelletize. But the
> outer plant parts have high concentrations of nutrients which cause 
> slagging
> in the hot firebox. So they have only been used in local pellet stoves in
> combination (50:50) with wood pellets. I don't know of anyone who is using
> them on a regular basis as fuel these days. Not many feed pellet mills are
> set up for whole straw in our area. One that was closed his doors when he
> retired some years ago. His pellets sold at prices competitive with grass
> hay which has about the same (low) nutritional value.
>
>
> Tom
>
>
>
>
>
>
>
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> Bioconversion at listserv.repp.org
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> 

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