I thought I'd throw this question out in this forum, knowing there are some 'guru's' here on the subject of biodiesel processing. By the way, I've posted this same question on another biodiesel forum without any definitive answers.

I am in the process of making another processor, and ideally would like to use copper tubing in the plumbing. My main reason is to enable me to create a more compact, cleaner draining, and tidier system. It's a 55 gallon drum set up, and I do a single stage process with KOH. I also use the same processor to spray dry the bio with heat, so after it's done in the wash tank, it gets transferred back to the cleaned processor for drying.

The reason I even considered using copper was after seeing pictures of Graham Lamings processor. He uses copper in the plumbing, so one would think that this is ok. However, when it was brought up on another forum, most of the responses were that it should not be done. It was never adressed, however, how Graham was able to get away with it and I would think that if anyone knew what they were doing it would be him.

Any and all thoughts on this would be appreciated.

 

I've used copper and brass for years and have not noticed any problems. LONG term STORAGE in copper might corrode some of the copper away, but if you drain the system on a regular basis I don't see any problem.

 

Thanks Don, I was hoping you'd chime in on this. I think I will move forward with plumbing my new processor with copper.

 

The fact is copper accelerates polymerization in VO and biodiesel. While it may not pose a noticable problem for some, avoiding it in your design would be best. Aluminum tubing is cheaper and has almost no effect on VO/bio-d. (I use compression fittings etc commonly used on copper)

 

Thanks for your input. It's greatly appreciated. Since copper is so widely used in the UK, I figured it would be ok. I've even seen entire processor tanks made of copper. Turns out many of the water heater tanks across the pond are constructed with copper.

Anyway, with regard to the polymerization issue, I produce bio for myself (and some for my dad too), and make fairly small quantities (45-90 gal./month), so none of it sits for any longer than a month to 6 weeks. My thinking here is that any effects of polymerization would be fairly minimal.