55gal processor

Hello,

I'm about to build a 55gal processor and wanted to run the design past 
ya'll.

I've got a 55gal drum w/ top + ring seal.
I'm going to have a buddy weld a drain pipe in the bottom and an inlet 
pipe near the top on the side. Not using the cone
bottom design.

I'll be putting the barrel up on a stand to allow clearance 
of the drain pipe.

I'm going to get two 220v water heater elements + themostat from 
HomeDepot. Drill two holes in the sides and mount the
elements in the holes, seal & weld it up.
The plumbing of recirculation, methoxide mixing, draining, will be done
similar to the appleseed piping.

I've got two food grade barrels for storage of wvo and fuel.

Any issues I should think about before punching holes in my steel drum?

I'm still working on my 1/2 liter process with old canolda oil + KOH + 
methanol. First batch failed the wash test and turned into a white 
solution on top, dirty water on the bottom. Is there any recovery from this point 
or should I dispose of it?

People say 'wash gently' or 'mist' but it seems like those are avoiding
what is really a quality problem.

Thanks
-Zetan