I ran the Orion diesel making machine after a lengthy refitting. A number of refinements were commissioned including brick refractory, revised retort weighing mechanism, I.D. (induced draft)fan and preheater.
240 liters of .848SG was made during actual production time of about 8 hours. Feedstock was a variety of waste mineral oils.
There was number of problems:
The reflux vessel had some leaks which were fixed.
Extra retort insulation was added and it was noted there was 60+ degrees of difference between lower and upper TC sensor probes.
The feed pump struggled, the cause discovered the following day as a kinked hose.
Improved feedstock quality put an end to previous boil-over episodes. Throughout the 8 hour production, amber diesel never ceased to flow through the sight glass, albeit at varying rate.
The run highlighted some useful information.
High flame temperature was needed so more insulation is required on the retort vessel.
The preheater can get really hot with temperature of 400°C+ noted. More insulation would benefit efficiency. Hot feedstock was optionally be piped back to the in-tank allowing heating of the vessel and separation of suspended water.
The production rate at low retort levels has some good things going for it. It requires less heat to evaporate and runs at a good speed. Sadly the failing feedstock pump didn't allow proper testing.
Next run I'll start with little or no feedstock in the retort then begin to add enough to suit the applied temperature. Ultimately I hope to adjust feed flow to raise/lower retort target temperature.
The retort weighing device worked much better than previous iterations. With reasonable accuracy I could determine empty-to-full status. Later refinements could include a strain gauge with LCD readout, alarms and programmed automation of pumps and valves.
It appears that the refractory bricks require a lot of warming up but they are impervious to direct flame heat. In addition these dense bricks are heat stores/conductors but poor insulators.
Various pipe threads throughout the plant (except retort/reflux zone) were sealed with automotive exhaust cement. This worked well so I'll be carefully evaluating.
Pics of the various modifications to follow, see appropriate pages of this blog..
Upgrades before next run could include: heat recovery, insulation, preheater. Also I'm pondering on making an operator checklist to ensure vital components like valves are correctly set.