G'day All,
The physical/chemical/thermodynamic(?) properties of methane mean it won't liquefy at ambient temperatures (at any pressure!), so LNG transport has to be refrigerated (MORE energy!). It's a bit like nitrogen (but does not need to be quite that cold). My simple engineers explanation is to look at the series of methane, ethane, propane, butane, heptane, hexane, septane, oxane, nonane, decane, .... (with one, two, 3, ..., 10, ... carbon atoms). The first couple are gases at ambient temperatures, the next couple volatile liquids, then more stable liquids then greases and eventually solids - the conclusion is the lower the number of carbons the lower the boiling point. Happy digesting, HOOROO Mr. Paul Harris, Room S116b, Waite Main Building Faculty of Sciences, The University of Adelaide, Waite Campus, PMB 1, Glen Osmond SA 5064 Ph : +61 8 8303 7880 Fax : +61 8 8303 4386 <mailto:[email protected]> mailto:[email protected] <http://www.adelaide.edu.au/directory/paul.harris> http://www.adelaide.edu.au/directory/paul.harris CRICOS Provider Number 00123M This email message is intended only for the addressee(s) and contains information that may be confidential and/or copyright. If you are not the intended recipient please notify the sender by reply email and immediately delete this email. Use, disclosure or reproduction of this email by anyone other than the intended recipient(s) is strictly prohibited. No representation is made that this email or any attachments are free of viruses. Virus scanning is recommended and is the responsibility of the recipient. From: [email protected] [mailto:[email protected]] On Behalf Of Reuben Deumling Sent: Wednesday, 24 November 2010 3:33 AM To: For Discussion of Anaerobic Digestion Subject: Re: [Digestion] Compressing of biogas Can you say a bit more about - why separating out the CO2 is ruled out? and - why if methane 'does not like to be compressed' so many other similar gases are compressed regularly? Perhaps I'm missing something. I do appreciate the transport ideas without compression or a pipeline. Reuben Deumling On Tue, Nov 23, 2010 at 8:58 AM, Alexander Eaton <[email protected]> wrote: We go around this issue frequently, as end users often come up with the same idea. It is hard to tell them no, so we always take a fresh look under the circumstances. At the end of the day filtration of CO2 i always ruled out, and that means 40% of the volume of gas you are compressing serves no energetic purpose. Add that to the fact that methane does not like to be compressed, and we arrive again at a "no" response. The one option we always examine is the non-compressed transportation of large gas reservoirs. This we have tried for distances that are too long for a simple gas line, and short enough to be practical by cart. Since we can make durable gas reservoirs of any size and shape, this is not unfeasible. Once transported, the gas is connected and used as usual, while a second reservoir is filling. If you can create value for this use, and the transport logistics to not out-weight the value of the energy provided, you may have an option for success. Others have used large truck inner-tubes in the same way, that are then rolled down the street to the end use. I suspect that in certain locations, systems that considered low-pressure distribution could gain some traction. Saludos, A On Tue, Nov 23, 2010 at 6:21 AM, Vianney Tumwesige <[email protected]> wrote: Hello Harold, I completely agree withYvonne, it will be economically expensive to compress the gas. P.S. Yvonne, could you send me a copy of the paper and ppt as well? Best regards On Tue, Nov 23, 2010 at 1:49 PM, Harold leffertstra <[email protected]> wrote: hello Got a question from the owner of a small biogass plant in Tanzania. He is expanding a small existing biogas plant to be able to digest waste from 200 households and manure from 100 cows. He is interested in using the biogas for fueling vehicles. In our part of the world we think it will be necessary with cleaning, uppgrading of the gas and compressing. Do any of you have experience/ideas about whether this is feasible for such a small plant? 1)What is necessary to use the biogas for fueling vehicles and 2) what are the technical and economical consequences? Thank you Harold Leffertstra Senior Advisor Norwegian Climate and Pollution Agency Oslo _______________________________________________ Digestion 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/digestion_lists.bioenergyli sts.org for more information about digestion, see Beginner's Guide to Biogas http://www.adelaide.edu.au/biogas/ and the Biogas Wiki http://biogas.wikispaces.com/ -- Vianney Tumwesige Director - Green Heat (U) Ltd Error! Filename not specified. P.O. Box 10235 Kampala-Uganda 256 (0) 71 237 9889 "The more people are self sufficient in cooking fuel, the more personal and financial freedom they have." - Emma Casson <http://trustvianney.wordpress.com/> _______________________________________________ Digestion 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/digestion_lists.bioenergyli sts.org for more information about digestion, see Beginner's Guide to Biogas http://www.adelaide.edu.au/biogas/ and the Biogas Wiki http://biogas.wikispaces.com/ -- Alexander Eaton Sistema Biobolsa IRRI-Mexico RedBioLAC Mex cel: (55) 11522786 US cel: 970 275 4505 [email protected] [email protected] sistemabiobolsa.com www.irrimexico.org www.redbiolac.org _______________________________________________ Digestion 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/digestion_lists.bioenergyli sts.org for more information about digestion, see Beginner's Guide to Biogas http://www.adelaide.edu.au/biogas/ and the Biogas Wiki http://biogas.wikispaces.com/
_______________________________________________ Digestion 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/digestion_lists.bioenergylists.org for more information about digestion, see Beginner's Guide to Biogas http://www.adelaide.edu.au/biogas/ and the Biogas Wiki http://biogas.wikispaces.com/
