[Terrapreta] torrified wood vs. charcoal

[Gerald Van Koeverden]

Is torrefied wood going to replace charcoal in our barbecues?  It  
seems to be both more energy efficient and less polluting...

Gerrit

B: Torrefied Wood, Energy For The Future
At a global level, renewable energy is of increasing importance  
because of the greenhouse effect. Emissions from the burning of  
fossil fuels must be reduced, so alternative fuels are needed.  
Torrefied wood can be burnt in a conventional coal-fired power station.
But what is torrefied wood? The word comes from the French ‘bois  
torréfié’, which means “roasted wood”. This means that the first  
stage of carbonisation has taken place, without reaching the stage of  
charcoal.
Why pre-treat wood in this way, instead of burning it directly, for  
example in a bioenergy power station? Thanks to roasting, the fuel is  
better than ordinary biomass. Torrefied wood is wood that has  
undergone thermal drying and has a relatively high energy potential  
(20-22 MJ/kg), and is suitable for grinding in coal-grinding mills.  
It has an excellent combustion rate and low emissions. Moreover it is  
easy to store, even outdoors, since it is hydrophobic. Transport is  
relatively cheap.
Initial tests (phase I of the project) were carried out in 2003 in  
the Netherlands and Britain.


Results were very positive.
After the positive outcome of phase I, the partners in the project,  
BGP Ingenieursbureau BV and Stramproy Contracting BV, decided to  
continue. Phase II is currently in progress. The aim is to produce  
large quantities of torrefied wood. It is produced in a continuous  
process plant which can produce a tonne of torrefied wood per hour.
Many sectors of industry could be interested in this innovation,  
especially because of the implementation of the Kyoto Protocol, which  
allows mixed biofuels to be offset against CO2 emissions.
In future, it is believed that production will reach 10 tonnes an  
hour. In the meantime additional biomass will be provided by  
agriculture, the food industry, and forestry.
Info: H. Kroopman, hkr at bgp.nl - M. Verbeeten, mv at bgp.nl - info at bgp.nl

(MilieuDirect, Belgium, www.kluwer.be/kluwer/home.asp?doelid=3)



AN FAO paper:

http://www.techtp.com/tw%20papers/fao_paper.htm




-------------- next part --------------
An HTML attachment was scrubbed...
URL: /attachments/20080211/3072609b/attachment.html