It's called "black diesel" I know of a lot of guys that run it in IDI trucks and off-road equipment (industrial).
I wouldn't think it'd be that bad to run, after all, #2 is only filtered between 3 and 10 microns at the pump (if you're lucky), if you filtered WMO to 1-3 microns, and mixed it with regular diesel, I would think you'd be fine.
or you could do this:Waste Oil diesel refinery
2003 Chevy 2500HD D/A ECSB 221K (Sale pending)
EFI Live DSP5 (thank you to Dustin and Idaho Rob @ATP Trucks), batmowheel & BD wastegate (thanks to MrManners @ Synthetic Motorsports), Kryptonite tie-rods, MBRP downpipe and 4" straight pipe, 33" BF Goodrich A/T KOs on H2s
2007 LMM/Alli CCSB 4x4
EFI Live and downpipe/5"