[Bioconversion] RE: [Gasification] Cross-posting - clear subject - Bioenergy. EffectiveForums

Mon Apr 24 12:16:43 EDT 2006

Nils,

Thank you for your comments and suggestions. 

CROSS POSTING
Cross posting is a nuisance for everyone. Each list has 500-600 subscribers
so lots of people get unwanted mail. It is best to post a message to only
one list. If participants on other lists are interested in the topic then
they can find it for themselves by viewing the archives, subscribing to a
digest, or subscribing to the list. If 7 of our most active contributors
would post to only one list at a time the cross posting issues would go
away.

Sometimes there is a lot of overlap in topics. Use your judgement about
where to post topics. They should be relevant to the specific forum. A lot
of the Gasification discussion that has been cross posted to Stoves has very
little interest or relevance to the stoves participants. Keep the discussion
on the most appropriate forum and let the participants subscribe to that
forum.  

ARCHIVES
All of the REPP lists are listed at
http://listserv.repp.org/mailman/listinfo

There are links from the individual list pages for bioenergy, bioconversion,
digestion, gasification, and stoves to the archives for those lists. The
archives are an easy way to review the discussion on each list. For example:

Gasification: http://listserv.repp.org/pipermail/gasification/ 
Stoves: http://listserv.repp.org/pipermail/stoves/

You don't have to subscribe to a list to view the archives. 

The Archives for all the lists can be searched by using the Google search
found on the repp site and on the list websites.  

DIGEST
Another way to receive fewer emails for lists of casual interest is to
subscribe to the digest mode in which you periodically receive a batch of
messages all in one message. Go to the list info page. So to "Unsubscribe or
edit options" Enter your login and password. (Everyone receives their
password for all their list subscriptions automatically at the beginning of
each month.)Toggle "Select Digest Mode" ON.  

WEB BASED FORUMS
We have the capability of creating web-based forums where multiple topics
can be run in parallel threads. This may be a good solution for bioenergy,
gasification or possibly bioconversion but it would exclude many people in
the field who are subscribers to stoves. Email is still the most reliable
communication method to areas with low-bandwidth dialup connections.

FUNDING
The discussion lists are hosted courtesy of the Renewable Energy Policy
Project (REPP) which is a non-profit organization. REPP will need additional
funding from donors, sponsors or participants to develop web based forums or
other enhancements. 

Tom Miles

-----Original Message-----
From: gasification-bounces at listserv.repp.org
[mailto:gasification-bounces at listserv.repp.org] On Behalf Of astrupgaard
Sent: Monday, April 24, 2006 3:34 AM
To: gasification at listserv.repp.org; bioenergy at listserv.repp.org;
bioconversion at listserv.repp.org; STOVES at LISTSERV.REPP.ORG
Subject: [Gasification] Cross-posting - clear subject - Bioenergy.
EffectiveForums

Dear Community and moderators

I used to be a member of three lists back in my former employment. However,
today I am only member of two and it seems all the juice is more or less
served on "gasification".

Being on three lists filled up my mail box since, a lot of mails were
cross-posted. This is why I skipped the very interesting "stoves" list.
However I am still a member of the rather inactive Bioenergy-list that used
to be the forum for all that matters.

There is an urge to let people subscribe to the "Bioconversion" list and a
lot of subjects should move to that list instead of being on "gasification".
If you have an interest in some of these subjects you will need to subscribe
to "bioconversion" which will only cause more cross-posting. (Some of the
subjects would probably be better of if they were handled on the "Bioenergy
list")

I wonder whether "Bioenergy list" could be used as a list that actually
compiles all input from the different "sublists"?

Replying on Bioenergy list would go to the specific sublist - and of course
to Bioenergy. Hence if you have a broad interest in the area you only need
to subscribe to "Bioenergy" and you will have everything. 

This would also leave the sublists to very specific matters related to
technology since all the political stuff etc would go to "bioenergy" - and
cross-postings would be dead meat.

The only thing left would be to have everybody to write a clear subject
title in order speedily to be able of deleting mails of minor interest to
the single subscriber.

Best wishes for effective forums.

Med venlig hilsen
ENVIPOWER AS

Nils Peter Astrupgaard
Snerlevej 1 DK-2800 Kgs. Lyngby
+45 4061 5600
npa at envipower.dk

-----Original Message-----
From: gasification-bounces at listserv.repp.org
[mailto:gasification-bounces at listserv.repp.org] On Behalf Of Dries
Vansteenkiste
Sent: 24. april 2006 10:43
To: gasification at listserv.repp.org; Stoves
Subject: Re: [Gasification] variability of energy content in woody biomass

(i cross-posted this to Stoves-list)

the taxonomical classification into hardwoods and softwoods has indeed to do

with reproduction.
Hardwoods are Angiosperms (seeds are covered, includes most broadleaved
species such as poplars and oaks) and softwoods are Gymnosperms (seeds are
"naked", e.g. in cones of pines, coniferous species). Exceptions exist: 
Ginkgo biloba has broad leaves, but it is considered a softwood. Wood
structure also matters: hardwoods are characterised by the presence of large

pores (vessels), which may be viewed as long cylindrical tubes conducting
water from roots to leaves - these are absent in softwoods (they use
tracheids for water conduction). Wood density is a function of cell wall to
lumen ratio: the more cell wall matter, the denser (and therefore, most
often, the harder).

The wood of hardwoods may be "soft" or "hard", that of softwoods equally,
but most hardwoods (esp. certain tropical species) are harder and denser
than softwoods (such as Pine, Spruce, Fir).

Balsa (Ochroma lagopus) has a very soft light wood (OD density < 200 kg/m3)
but it is a broadleaved species, hence a hardwood species. Oak wood is much
harder and usually has a denser structure (OD density 600-900 kg/m3).  -

Growth rate usually plays an important role in determining the "hardness" or

density of wood: slow grown oak is much lighter and softer than fast grown
oak - the opposite is usually true for coniferous woods: the faster the
growth, the lighter and softer the wood.

We all have the perception that certain woods burn better or release more
heat than others: overall, from previous replies to my mail, dense woods are

considered to be more valuable from an thermodynamic point of view. 
Therefore, wood of heavy hardwoods (beech, birch, oak, black locust) is
considered a better firewood than wood of light hardwoods (poplar) or
softwoods (pine). However, the presence of resins seems to interfere with
this (release of volatiles improves burning efficiency esp. in softwoods
such as pine, larch?). Someone else mentioned that willow (a low to medium
density hardwood) is a very good firewood when it is sufficiently dry. The
latter is true for all woods (the drier, the higher the heating value). This

brings me back to the original reason for starting up this discussion
thread: wood structure and the way wood is processed for energetic purposes
seems to matter much more than we are forced to accept if we only use HHV
and LHV as absolute measures of the energetic potential of a fuel.

It is still not clear to me - perhaps I should start studying thermodynamics
- whether:

Scenario A: oxydative combustion of dry wood in excess oxygen (which yields
the higher heating value)

will yield the same, a lower or an equal amount of "energy" (being it heat,
electricity, kinetic energy) as

Scenario 2. the dry wood is pyrolysed, gasified or fermented and the
products (being it either tar, gas mixture, ethanol, hydrogen and/or
methane, etc.) are combusted or used as a fuel in sub-stoichiometric oxygen
conditions?

(to be continued)

Dries

Dries Vansteenkiste
Laboratory of Wood Technology
Faculty of Bioscience Engineering (FBE)
University of Ghent
Coupure Links 653
9000 Gent
Belgium
e-mail Dries.Vansteenkiste at UGent.be
web http://www.woodlab.be

----- Original Message -----
From: "Mark Ludlow" <mark at ludlow.com>
To: "'Kurt T'" <rkurt at tadaust.org.au>; <gasification at listserv.repp.org>
Sent: Saturday, April 22, 2006 1:36 AM
Subject: RE: [Gasification] variability of energy content in woody biomass

> Something to do with sex.
>
> All plants are classified according to their means of reproduction.
>
> Hardwood (angiospermous) trees are grown here in the NW on 7-year 
> rotations,
> for Kraft pulp. Coniferous trees are all classified as softwood, 
> regardless
> of whether their woods are hard or soft.
>
> For those that heat with wood, pitch-pine ("Georgia Fatwood") or its
> equivalent, is favored as a fire starter--due to its high resinous VOC
> content.
>
> Mark
>
> -----Original Message-----
> From: gasification-bounces at listserv.repp.org
> [mailto:gasification-bounces at listserv.repp.org] On Behalf Of Kurt T
> Sent: Thursday, April 20, 2006 6:58 PM
> To: gasification at listserv.repp.org
> Subject: Re: [Gasification] variability of energy content in woody biomass
>
>
> At 12:34 AM 4/21/06, Brad Clements wrote:
>
>>On 20 Apr 2006 at 15:52, Dries Vansteenkiste wrote:
>><<snipped>>
>>But this still gets back to biotech. Does softwood grow faster than
> hardwood?
>
> The technical difference between "soft wood" and "hard wood" is a matter 
> of
> structure, not density. Balsa for instance is actually classed as a "hard
> wood". Something to do with the vesicles, I vaguely seem to remember.
>
> Kurt
> n
>
>
> -- 
> No virus found in this outgoing message.
> Checked by AVG Anti-Virus.
> Version: 7.1.385 / Virus Database: 268.4.4/318 - Release Date: 4/18/06
>
>
> _______________________________________________
> Gasification mailing list
> Gasification at listserv.repp.org
> http://listserv.repp.org/mailman/listinfo/gasification
>
>
> _______________________________________________
> Gasification mailing list
> Gasification at listserv.repp.org
> http://listserv.repp.org/mailman/listinfo/gasification
> 

_______________________________________________
Gasification mailing list
Gasification at listserv.repp.org
http://listserv.repp.org/mailman/listinfo/gasification
_______________________________________________
Gasification mailing list
Gasification at listserv.repp.org
http://listserv.repp.org/mailman/listinfo/gasification