>My question to the group involves a 55 gallon drum used as a >processing tank. If the mixing shaft were to be lowered straight >down into the center of the tank, would adequate mixing take place? >Or would a vortex form in the mixture and inadequate mixing take >place? I see some tanks have the mixer angled on the side of the >drum, I'm assuming to avoid having a vortex form. Would baffles >along the inside of the drum help? Thanks. Jonathan.
Yes, baffles would help to increase agitation, presuming you know how much agitation you need. Why would a vortex mean inadequate mixing? Chuck Ranum has his mixer set at an angle from the side but still talks of a vortex. If the mixer turns fast enough you'll get a vortex whatever angle it's set at. How far down does the vortex go, all the way down to the mixing blades? Perhaps that would be too much, but the answer would be to decrease the speed or the angle or size of the mixing blades. Anyway, Jonathan, why not use a pump instead? Aleks Kac did some research on this and told me this: "As a rule of thumb you need 1000 W of shaft power for pump stirring on a 1000 litre/batch reactor as opposed to 3000 W of shaft power for turbine stirring for the same volume." I think pumps work better than stirrers, and it's a lot simpler to build a closed, fume-free processor with a pump. These 1" Clear Water Pumps are cheap and reliable, and work very well. Harbor Freight Tools -- 1" Clear Water Pump -- Item 1479-1VGA http://www.harborfreight.com/ Northern Tools -- Cast Iron 1in. Clear Water Pump, Model# 109955 (Warning -- very BAD at dealing with international orders!) http://www.northerntool.com/ Northern Tool & Equipment Co. (UK) Ltd. -- 1" Clear Water Pump, Item No. 109955E http://www.northerntooluk.com/ Best Keith ------------------------ Yahoo! Groups Sponsor ---------------------~--> Buy Ink Cartridges or Refill Kits for your HP, Epson, Canon or Lexmark Printer at MyInks.com. Free s/h on orders $50 or more to the US & Canada. http://www.c1tracking.com/l.asp?cid=5511 http://us.click.yahoo.com/mOAaAA/3exGAA/qnsNAA/FGYolB/TM ---------------------------------------------------------------------~-> Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Biofuels list archives: http://infoarchive.net/sgroup/biofuel/ Please do NOT send Unsubscribe messages to the list address. To unsubscribe, send an email to: [EMAIL PROTECTED] Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/biofuel/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/