TDI Bio

With any luck, I'm only 2-3 weeks from having my processor setup. Which is good, since my WVO supply is kicking out 30-40 gallons a week! I've included a picture of my draft plans. Click on the picture to see it magnified. It's currently in Visio.

Comments on some of my design decisions:
1) I can't weld, so can't fix-up a discarded water tank. I also don't want to spend $220 on a new water tank, so I've decided to forego a water-heater tank and go with a 55-gallon drum with built-in agitator. I added the built-in agitator to compensate for my smallish pump, and to permit me to process batches of up to 40 gallons WVO at a time, but also accomodate 10-gallon batches if I so choose. By using both agitation and circulation, it should mix my processing tank nicely.
2) I'm wondering about going pure gravity feed for the methanol/KOH mix.
3) I'm not sure if I'll want to put additional valves on the filters to isolate them, so there would be valves both upstream and downstream from the filters, while keeping them serial.
4) There are a few fuzzy details on my design:
a) agitator motor - will likely be salvage motor from the first major appliance I see by a curb, or a drill.
b) methanol tank - to process batches of 40 gallons, I'd need an 8-gallon tank. I've got lots of 10-gallon drums I could use, but then I can't see when the methanol is mixed up. Serially-linked carboys perhaps? I'm still working on an economical solution for the methanol tank, suggestions welcomed. (Sure $46 HDPE carboys are easy to suggest, but that'd be over $100 with shipping!)
c) agitation of methanol tank - if I wind up using a 10-gallon closed drum, how to agitate, and how to ensure the mix is mixed?
d) wash tank - would I need to heat the wash tank?
e) distillation of methanol - how to recover the precious methanol from the glycol byproduct?

As you can see, several more questions to be addressed in the design.