[Digestion] Digestion Digest, Vol 16, Issue 2

Tue Oct 9 23:42:55 EDT 2007

> Message: 1
> Date: Mon, 8 Oct 2007 12:27:28 -0400
> From: "mrcdb" <mrcdb at charter.net>
> Subject: Re: [Digestion] Digestion Digest, Vol 16, Issue 1
> To: <digestion at listserv.repp.org>
> Message-ID: <001801c809c8$1e424d70$9865fea9 at Wanderer>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> 	reply-type=original
>
> Hello All,
>
> I am an Energy Consultant in Erie, MI,  USA
>
> I have been researching anerobic digestion lately as related to Municipal
> Solid Waste (MSW) landfills and landfill gas to electric plants.
>
> I am a member of the Solid Waste Association of North America (SWANA) and
> just completed their landfill gas ecourse.
>
> Anyway, in their course they state that "a moisture content, of the
> digestion material, of 38-40% is ideal for the most methane production"
> and
> that "recirculating the leachate produces lots of gas"
> They say that a moisture content much over 40% is a saturated condition,
> and
> will slow or stop methane production!
>
> So, it seems to me, that a digester full of water is not an efficient way
> to
> produce methane?
>
> Does anyone have any thoughts on this subject?
>
> Thanks,
>
> Charles Bagwell
> President
> Zerwell Energy
> www.zerwellenergy.com
> Erie, MI
>
>
>
>
>
> ------------------------------
>
> Message: 2
> Date: Mon, 8 Oct 2007 18:00:56 +0100
> From: "Duncan Martin" <duncanjmartin at eircom.net>
> Subject: Re: [Digestion] Sailing
> To: "Alejandro Bustamante" <labrava4 at yahoo.com>,
> 	<digestion at listserv.repp.org>
> Message-ID: <01c601c809d0$73a96cf0$7733869f at Dell1>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> 	reply-type=original
>
> I'm not so sure how far this analogy works! It might be quite misleading.
>
> If you conceptually replace your yacht with something with the size, cost
> and manoeuvrability of a crude oil tanker, you might be in the right frame
> of mind.
>
> Duncan
>
> Chair
> Republic of Ireland Centre
> Chartered Institution of Wastes Management
>
> ================================
> CONTACT DETAILS
> Duncan J Martin, PhD, CEng, CSci, MIEI, MCIWM, MIChemE
> 24 Townsfield, Cloughjordan, N Tipperary, Ireland
> Mobile: +353 86 8377 906
> Home: +353 505 42087
> Email: duncanjmartin at eircom.net
> ================================
>
>
>
>
> ----- Original Message -----
> From: "Alejandro Bustamante" <labrava4 at yahoo.com>
> To: <digestion at listserv.repp.org>
> Sent: Monday, October 08, 2007 2:27 PM
> Subject: [Digestion] Sailing
>
>
>>
>>
>> I am a sailor, I have been for all the 72 years of my
>> life, I started sailing as a baby on my fathers boat.
>> Now that I am landlocked I think that to convert
>> manure into gas is the closest thing to sailing you
>> can do on land.
>>
>> Alejandro Bustamante
>>
>>
>>
>> ____________________________________________________________________________________
>> Shape Yahoo! in your own image.  Join our Network Research Panel today!
>> http://surveylink.yahoo.com/gmrs/yahoo_panel_invite.asp?a=7
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>>
>>
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>> Beginner's Guide to Biogas
>> http://www.adelaide.edu.au/biogas/
>> http://info.bioenergylists.org
>>
>>
>>
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>> Version: 7.5.488 / Virus Database: 269.14.4/1056 - Release Date:
>> 07/10/2007 18:12
>>
>>
>
>
>
>
> ------------------------------
>
> Message: 3
> Date: Mon, 8 Oct 2007 20:28:15 +0100
> From: "Duncan Martin" <duncanjmartin at eircom.net>
> Subject: [Digestion] % water in landfills
> To: <digestion at listserv.repp.org>
> Message-ID: <020e01c809e1$60c11fa0$7733869f at Dell1>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> 	reply-type=original
>
> Charles and all
>
> I think the guideline that 38-40% H2O is best in landfills relates more to
> the need to avoid XS water, which greatly increases the volume of leachate
> to be contained and managed.
>
> Saturation with water doesn't seem likely to inhibit the process -
> otherwise, how does conventional AD work? It's often said to do so but I
> think that's based on the widespread assumption that the reaction
> mechanisms
> in LFG generation are the exact same as in AD.
>
> If you check out my research publications between 1999 and 2005, you'll
> find
> I propose an alternative that makes more sense: the Reaction Front (aka
> Microreactor in some earlier papers). The basic microbiology and
> biochemistry are the same but I think the major reactions in a landfill
> might take place INSIDE the solids.
>
> One reason for this is that the liquid fraction in a real landfill (unlike
> many lab models) is usually very high in inhibitory VFAs (Volatile Fatty
> Acids), so it's hard to see how much reaction could take place in the
> liquid
> phase. If so, any inhibitory effect of liquid saturation in landfill might
> be due to the much greater mass of VFA it would contain.
>
> Best regards
>
> Duncan J Martin
>
> Chair
> Republic of Ireland Centre
> Chartered Institution of Wastes Management
>
> ================================
> CONTACT DETAILS
> Duncan J Martin, PhD, CEng, CSci, MIEI, MCIWM, MIChemE
> 24 Townsfield, Cloughjordan, N Tipperary, Ireland
> Mobile: +353 86 8377 906
> Home: +353 505 42087
> Email: duncanjmartin at eircom.net
> ================================
>
>
>
>
> ----- Original Message -----
> From: "mrcdb" <mrcdb at charter.net>
> To: <digestion at listserv.repp.org>
> Sent: Monday, October 08, 2007 5:27 PM
> Subject: Re: [Digestion] Digestion Digest, Vol 16, Issue 1
>
>
>> Hello All,
>>
>> I am an Energy Consultant in Erie, MI,  USA
>>
>> I have been researching anerobic digestion lately as related to
>> Municipal
>> Solid Waste (MSW) landfills and landfill gas to electric plants.
>>
>> I am a member of the Solid Waste Association of North America (SWANA)
>> and
>> just completed their landfill gas ecourse.
>>
>> Anyway, in their course they state that "a moisture content, of the
>> digestion material, of 38-40% is ideal for the most methane production"
>> and
>> that "recirculating the leachate produces lots of gas"
>> They say that a moisture content much over 40% is a saturated condition,
>> and
>> will slow or stop methane production!
>>
>> So, it seems to me, that a digester full of water is not an efficient
>> way
>> to
>> produce methane?
>>
>> Does anyone have any thoughts on this subject?
>>
>> Thanks,
>>
>> Charles Bagwell
>> President
>> Zerwell Energy
>> www.zerwellenergy.com
>> Erie, MI
>>
>>
>>
>> _______________________________________________
>> Digestion mailing list
>> Digestion at listserv.repp.org
>> http://listserv.repp.org/mailman/listinfo/digestion_listserv.repp.org
>> Beginner's Guide to Biogas
>> http://www.adelaide.edu.au/biogas/
>> http://info.bioenergylists.org
>>
>>
>>
>> --
>> No virus found in this incoming message.
>> Checked by AVG Free Edition.
>> Version: 7.5.488 / Virus Database: 269.14.4/1056 - Release Date:
>> 07/10/2007 18:12
>>
>>
>
>
>
>
> ------------------------------
>
> _______________________________________________
> Digestion mailing list
> Digestion at listserv.repp.org
> http://listserv.repp.org/mailman/listinfo/digestion_listserv.repp.org
>
> End of Digestion Digest, Vol 16, Issue 2
> ****************************************
>
Charles,

Whatever it's validity int ehlandfill situation, it has no relevance for
anaerobic microbial action per se.

Mel

Melvin S. Finstein, Ph.D.
Emeritus Professor of Environmental Science
 Rutgers, The State University of New Jersey
Head, ArrowBio USA

105 Carmel Road
Wheeling, WV 26003
(304) 242-0341
Email: finstein at envsci.rutgers.edu
Skype: melvinfinstein