Torrefied-densified biomass

[Reedtb2@cs.com]

Dear All:

The widespread use of biomass energy depends on a convenient supply of large 
quantities of biomass.  Densification can help with this because it makes 
many kinds of waste into a very acceptable - desirable fuel.  Gasifiers, 
pellet stoves and woodgas stoves all benefit from using densified wood.  

In 1979 we found in static tests on pelletizing that 

Preheating reduced the needed pressure required by a factor of 2

Energy for densification was also reduced by a factor of 2 at 225 C

The energy content of the resulting pellets rose from 19.3 kJ/g at room 
temperature to 21.4 kJ/g at 225 C (23.0) at 250 C)

["Biomass Densification Energy Requirements", T. Reed, G. Trezek, and L. 
Diaz, in Thermal Conversion of Solid Wastes", J. L. Jones and S. B. Radding, 
ACS Symposium Series 130, Was. D.C., 1980.  I still have the pellets in my 
"museum".]

In a recent article the Asian Institute of Technology found significantly 
reduced energy and die wear from preheating biomass before pelletizing.  
                                                       ~~~~~

Now (1982 actually) comes torrefied wood, (wood roasted at 200-250 C to 
remove primarily water and CO2, leaving a higher energy content and, lower 
mass for shipping).  

The next obvious step would be to combine the two processes, Torrefying the 
wood and then immediately densifying it while it is hot and weak, thus 
compounding the benefits of both processes.  

If anyone is interested in pursuing this I would be happy to cooperate with 
them.  

In a message dated 12/19/00 8:41:32 AM Mountain Standard Time, 
heat-win@cwcom.net writes:


> Dear All,
>
> In connection with greenhouses you will find much interesting
> information re. charcoal and torrefied wood at .
>
> If for example tomatoes are being grown, the vines left over can be
> torrefied and used to fuel the greenhouse heating. If there aren't
> enough, then other renewable fuels such as wood pellets can be used.
>
> Regarding the lime kilns, have a look at , in
> particular the RofireTM link you will find there. Cement kilns are now
> being heated using RofireTM pellets made from the un-reusable fibres,
> plastic, etc, left over from the recycling of paper.
>
> Whatever else you do to counter the natural gas and oil price crises,
> please go out and plant more trees!
>
> Regards,
>
> Thomas J Stubbing
>
>
> John Flottvik wrote:



Thomas B. Reed
President - The Biomass Energy Foundation
1810 Smith Rd., Golden, CO 80401
Reedtb2@cs.com;  303 278 0558

Research Director,
The Community Power Corporation,
8420 S. Continental Divide Rd.
Littleton, CO 80127
303 933 3135