Both direct and indirect methods are used. Sometimes heat from the engine exhaust is transferred to drying air, or directly to the fuel, using a heat exchanger. The temperature of the moisture laden exhaust exiting from the dried material must be above the dew point of the gas. By the time you dilute the engine exhaust to a temperature suitable for drying the fuel without cooking it - usually 50C-120C/120F-250 F - the dew point is pretty low so you need to dry in a thin layer, like on a belt, or blow the gas through the fuel with enough velocity, and with enough time, to let the condensation layer work up through the pile of fuel. In a thick bed or bin the moisture condenses in a layer in the fuel until it gets hot enough to evaporate.
Tom -----Original Message----- From: Gasification [mailto:[email protected]] On Behalf Of Mark Elliott Ludlow Sent: Wednesday, March 23, 2016 8:34 PM To: 'Discussion of biomass pyrolysis and gasification' <[email protected]> Subject: Re: [Gasification] Gasification Digest, Vol 67, Issue 2 ...however, it's temperature quickly falls! Automotive exhaust systems rust away primarily because of condensation of moisture in the exhaust stream. Others have pointed-out that condensation is a very effective way to transfer thermal energy, which drives moisture from the interior of fuel particles. This is phenomenon is effectively used in very many counter-flow drying apparati. Mark -----Original Message----- From: Gasification [mailto:[email protected]] On Behalf Of [email protected] Sent: Wednesday, March 23, 2016 7:56 PM To: Discussion of biomass pyrolysis and gasification <[email protected]> Subject: Re: [Gasification] Gasification Digest, Vol 67, Issue 2 Hi Dimitris, Engine exhaust cannot be saturated because it is over 100 Deg C. Only pure steam can be considered saturated at 100 deg c and 1 atm. Engine exhaust will have a saturation temperature that is decided by the molar% of H2O in the exhaust. This is typically around 55 Deg C. Regards Shivanand On 2016-03-23 23:08, Dimitris Tzagkas - KOKARAS AND ASSOCIATES wrote: > Dear Rolf,Leland,Nicolo > thank you for your replies, > but still I got no clue what "saturated" genset exhaust looks like > from physics point of view... > Anybody? > Best Regards > Dimitris > > On 22/3/2016 8:00 μμ, [email protected] > wrote: >> Send Gasification mailing list submissions to >> [email protected] >> >> To subscribe or unsubscribe via the World Wide Web, visit >> >> http://lists.bioenergylists.org/mailman/listinfo/gasification_lists.b >> ioenergylists.org >> >> or, via email, send a message with subject or body 'help' to >> [email protected] >> >> You can reach the person managing the list at >> [email protected] >> >> When replying, please edit your Subject line so it is more specific >> than "Re: Contents of Gasification digest..." >> >> >> Today's Topics: >> >> 1. Drying using a syngas genset exhaust >> (DIMITRIS TZAGKAS-KOKARAS & ASSOCIATES) >> 2. Re: Drying using a syngas genset exhaust (Energies Naturals >> C.B.) >> 3. Re: Drying using a syngas genset exhaust ([email protected]) >> 4. Re: Drying using a syngas genset exhaust (Nicol? Cerni) >> >> >> --------------------------------------------------------------------- >> - >> >> Message: 1 >> Date: Mon, 21 Mar 2016 20:50:01 +0200 >> From: "DIMITRIS TZAGKAS-KOKARAS & ASSOCIATES" <[email protected]> >> To: <[email protected]> >> Subject: [Gasification] Drying using a syngas genset exhaust >> Message-ID: <42F812A1CF574A238B33CED7CDEFE230@DimitrisPC> >> Content-Type: text/plain; charset="utf-8" >> >> Hello all. >> Has anyone ever tried to use the genset exhaust of a syngas driven >> genset in order to use it in a biomass dryer(rotary or something)? >> I can read in the literature that the syngas engine?s exhaust is >> saturated, but I cannot find experimental data anywhere. >> What does ?saturated? mean in numbers of relative humidity (%) or >> absolute humidity (gr/kgr)? >> >> Best Regards >> Dimitris >> -------------- next part -------------- An HTML attachment was >> scrubbed... >> URL: >> <http://lists.bioenergylists.org/pipermail/gasification_lists.bioener >> gylists.org/attachments/20160321/bf5a7819/attachment-0001.html> >> >> ------------------------------ >> >> Message: 2 >> Date: Mon, 21 Mar 2016 21:59:08 +0100 >> From: "Energies Naturals C.B." <[email protected]> >> To: [email protected] >> Subject: Re: [Gasification] Drying using a syngas genset exhaust >> Message-ID: <[email protected]> >> Content-Type: text/plain; charset=UTF-8 >> >> >> Hallo Dimitris, >> >> no idea if syngas exhaust behaves differently from diesel exhaust, >> but the latter comes out at around 400 ?C and can be very well used >> to dry wet biomass. It should be mixed with ambient air so as not to >> pyrolize or even ignite the biomass. >> I once spoke to people from Central America who had a very simple >> setup: >> A sort of tower where the raw biomass is filled in at the top and the >> exhaust/air comes from below in counterflow. >> They said that the humidity was driven off to the top and dry stuff >> could be taken out below. >> Seems simple... >> >> best regards >> >> Rolf >> >> >> >> >> On Mon, 21 Mar 2016 20:50:01 +0200 >> "DIMITRIS TZAGKAS-KOKARAS & ASSOCIATES" <[email protected]> wrote: >> >>> Hello all. >>> Has anyone ever tried to use the genset exhaust of a syngas driven >>> genset in order to use it in a biomass dryer(rotary or something)? >>> I can read in the literature that the syngas engine?s exhaust is >>> saturated, but I cannot find experimental data anywhere. >>> What does ?saturated? mean in numbers of relative humidity (%) or >>> absolute humidity (gr/kgr)? >>> >>> Best Regards >>> Dimitris >> > > -- > Φιλικά, > > Δημήτρης Τζάγκας > Διπλ.Ηλεκτρολόγος Μηχανικός - MSc > _______________________________________ > ΚΟΚΑΡΑΣ & ΣΥΝΕΡΓΑΤΕΣ > ΚΑΡΑΪΣΚΑΚΗ 12 > ΛΑΡΙΣΑ > Τ.Κ. 41222 > ΤΗΛ./FAX:2410256400 > www.kokaras.gr > _______________________________________ > > > _______________________________________________ > Gasification mailing list > > to Send a Message to the list, use the email address > [email protected] > > to UNSUBSCRIBE or Change your List Settings use the web page > http://lists.bioenergylists.org/mailman/listinfo/gasification_lists.bi > oenergylists.org > > for more Gasifiers, News and Information see our web site: > http://gasifiers.bioenergylists.org/ _______________________________________________ Gasification mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/gasification_lists.bioenergylists.org for more Gasifiers, News and Information see our web site: http://gasifiers.bioenergylists.org/ _______________________________________________ Gasification mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/gasification_lists.bioenergylists.org for more Gasifiers, News and Information see our web site: http://gasifiers.bioenergylists.org/ _______________________________________________ Gasification mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/gasification_lists.bioenergylists.org for more Gasifiers, News and Information see our web site: http://gasifiers.bioenergylists.org/
