Wiped Film Distillation Operation - Post 4

Wiped Film Still Operation - Post 4

Shutting Down

Shutting down is actually quite easy. It is a reverse of the start-up steps, except generally you don't get a cup of coffee.

The first thing to do is to start collecting the distillate and residue streams in a single container. That was any material collected during shutdown can be run the next day.

Then the evaporator should be cooled. It should be at least 150°C or cooler before continuing to the next step.

At this point the rest of the shutdown can be performed. The feed pump can be shut off, the wipers slowed down, the vacuum can be released and the cold trap can be turned off.

Once material stops coming out of the still, the gear pumps and condensers can be shut off. The system is ready to go for the next day.

In cases where a pass is concluding and another pass with one of the streams is next, there is a little trick to prepare for that. Prior to running out of materials, collect a decent amount (about 5 minutes of run time worth) of the stream that will be processed further.

Then, use that material for the shutdown material. That way all of the original feed can be fully run at the desired conditions, and the machine is left wet with the feed for the next pass. There won't be any lights left over from the original pass because that material was fully processed. Using the clean material as a "chaser" is a good way to prepare for the next pass. The chaser material can be collected and combined with the feed for the next day, because it is the same material.

I hope this little series has been helpful. Let me know if there is something you would like to learn about next. Please visit https://lnkd.in/gjQHSzPr to learn more about wiped film distillation and my services.

Photo courtesy of Pope Scientific, Inc.