I have just started this process and with posting on a biodiesel board most seem to think you can build a better, more cost efficient, processor if you are comfortable with fabrication and plumbing.
People seem to like plans supplied by Murphy's Machines.com if you are going to buy plans and would be interested in splitting some costs I would be interested or if you wouldlike to join me I am open to that.
Check out www.biodieselcommunity.org Theres plenty of info and diagrams to build your processor with out buying plans. Im building one now and its easy. If your lucky you sometimes can find a used electric water heater which you need for cheap or free.
I was going to get a few drums and some tanks to get started fabricating a BD setup. I was just planning on working with 55gal drums ($12ea for the open head drums). $55 for a drum with a cone bottom welded on it. Also for $35 I found a guy making a fitting to fit the 2" bung on a drum and threaded two 3/4" NPT ports.. install a pipe down into the drum and connect your pump to draw the oil up and connect to the other port for a simple way to mix. Add a inline injector to feed your methodixe. You can also get a tee connector ($10) where you could install your electric heating element inline with the pump then no need to weld a bung on the side of the drum.
But he also has 3 120gal propane tanks that have been washed out with acid.. $300 for all three if I wanted to go that route instead. Would it be worth it? Heavier guage steel and would allow larger batches. I was also thinking wouldn't a propane tank work well for collecting? Use a vacuum pump to draw the air out, then when collecting simply slowly open the valve to suck up the oil, then connect the compressor back at the shop to blow the oil out. No need for a pump and no worries of wearing a pump out.
I actually saw a electric water heater thrown out by the trash behind a restaurant.. what would you need one for? The elements are cheap, I can get a 18" long (doulbes back) 220V 6000W for $16 (put 110V to it and effectively you have a 2000W heater with a large surface area)
The part that I am not sure about how to design is the meoh recovery. I have seen a few diagrams but I still don't see how to do it in a way that makes for simple and straight forward operation. Also the water wash.. where am I to put all that water? The shop doesn't have any drains, and the house in on septic so I wouldn't want to be filling it with water. Do I need to build settling ponds? Or is the volume less than I am imagining it to be?
I was looking in to getting a processer from beachbioinc.com looks good and comes with the purolite filter. I have the know how to make one if I just could find one to look at. I am a diesel tech for a large rental company and allready have plenty of equipment to test on.