1000 Liter Polyethylene Wash Tank Plans
By Rick Da Tech
Washing has always been a bottleneck in making biodiesel. While you can make a batch in a few hours, it can take days to wash it. ProjectPurity from infopop overcame that bottleneck with this standpipe wash tank using a 275 gallon tote tank. He would make multiple 55 gallon batches loading them into the tote after settling. The tote can wash up to four batches reducing overall production time for the four batches by a week.
The problem with making a standpipe tote is that there is only one drain. In order to make a second drain he used the manifold. The key component is the double sided bushing. It has three sets of pipe threads in it. One set of 2" male threads and two 3/4" female pipe threads. When this bushing is screwed into the 2" Tee mounted on the tote's drain, run a 3/4" pipe inside of the TEE and through the tote's drain. On the side of the tee is the low drain. Oil flows around the 3/4" pipe in the drain out the side of the TEE. One outlet on the side of the tee is all that's needed, but he added a second outlet in order to be able to use dedicated plumbing for the unwashed biodiesel in and the water drain out. The third outlet on the end of the tee is from the standpipe.
In the picture below showing the inside of the inside of the tote the long black pipe is where the standpipe connects. The length is such that the elbow is directly below the opening on the top of the tote.
In this picture you can see the original PVC standpipe leaning against the tote. It has been replaced with black pipe. The standpipe is a pipe nipple to give the standpipe height, a 3/4" cross for the drain, and an extension going up to just below the lid for attaching a wrench to tighten everything up without cutting a big access hole in the top of the tote.
Large (200gal) Wash Tank - archived infopop thread