Hi Chester,

The indirect tank is fine, same as mine.

Regards,

Did you have to cut out the internal coil?

Hi Chester,

No, just leave it in.

Regards,

Makes sense now that I think about it, I suppose the coil would actually aid the mixing process

Do you know if those central heating pumps can be run dry, even for a short period of time?

Hi Chester,

I don't recommend running dry, though I'm sure after running a brew of BD there's plenty of lube available. More so than with water.

I run mine dry for a few seconds before making a brew, just to make sure the impeller is still running free. Always been OK.

Considering how little time a pump will run in a biodiesel process, compared with central heating, I expect it should last many many years, and should tolerate a fair amount of dry running provided you've run BD thru it recently.

As to the coil, yes, it gets hit with the flow from the pump, so as you say, probably helps the mixing a bit.

Hi,
I have just tried my first batch(70l)of bio-diesel in a hot water cylinder reactor.Followed all the steps in Girl Marks book,everything went according to plan,mixed for 2 hours,left overnight.When i checked next day,'DISASTER',during the night the tank was completely sealed and a vacumn must have formed in it(due to the cooling?).As a result the sides of the tank collasped inwards,worse still,I got very little conversion in the oil.Has anyone else had this problem?What can I do with the part processed oil?
Regards VINO

Oops!

Don't forget the vent tube in the top of the tank.

What makes you say you got very little conversion?

How did you fix the vent into the bottom (top) of the water tank? mine is solid copper

Welding sounds far too difficult for me.

Hi Chester

I drilled a hole in the base to take a brass 15mm tank coupling.

I got a broomstick with bluetack on the end and stuck the tank fitting onto it.

I poked the broomstick in thru the electric heater hole and pushed the male threaded section of the tank connector out thru the hole and then spun the nut on it so it wouldn't fall inside again.

Then I soldered the thing in place. You don't have to solder it, but it keeps it put!

Then fit your pipe into the compression fitting. If you didn't solder it in, use a pipe wrench to grab onto the male thread to stop it turning as you tighten up the comp. fitting.

Here's a pic ...



Hope that helps

quote:

Originally posted by Chester:
How did you fix the vent into the bottom (top) of the water tank? mine is solid copper

Welding sounds far too difficult for me.

I used a similar method to Graham 'cept I used 22mm pipe rather than 15 (extra safety!) and a 1" iron to 22mm compression fitting like this:-

I turned off the pipe thread and soldered the modified fitting into the hole I made in the top (bottom!!) of the tank. There's no real need to turn the thread down in a lathe - it just gives you a wider flange for a more secure soldered joint. It works fine but Graham's way is probably easier, especially if you can't solder - in which case, silicone sealer is your friend!

Nick

HI,
I had a vent on top with a valve which I opened during filling and heating the oil,but I kept closed during mixing and overnight while the oil settled.Is this not the idea of a closed system?
Last night I emptied the reactor,got about 10L dark brown liquid(glycerol),the rest a cloudy light brown colour.Started with 70L oil+15L methanol.What can I do with the oil?
P.S.Used compressed air to get the copper tank back into shape.
Regards
vino

quote:

Originally posted by vino:
HI,
I had a vent on top with a valve which I opened during filling and heating the oil,but I kept closed during mixing and overnight while the oil settled.Is this not the idea of a closed system?

Definately not with the copper cylinders we use in the UK. They are not pressure vessels in the way that the stainless steel water tanks our friends across the pond use in their Appleseed processors are. Theirs are built to work at mains water pressure but ours are only meant to withstand a positive pressure equivalent to the head of water from the header tank (ie not much). They are not designed to withstand a negative pressure of any kind. It is crucial to leave a vent open to the outside, even when reacting, unless you can devise a presure relief valve that will operate below the safe working pressure of the cylinder and also allow the ingress of air when under negative pressure to prevent the cylinder collapsing.

Cheers
24/7

quote:

Originally posted by vino:
HI,
I had a vent on top with a valve which I opened during filling and heating the oil,but I kept closed during mixing and overnight while the oil settled.Is this not the idea of a closed system?

Having further considered this, I am very concerned that someone is going to get hurt because they follow widely published procedures that are fine when using a stainless steel vessel but potentially deadly using a copper immersion heater tank.

THE UK PROCESSOR DESCRIBED IN THIS THREAD IS NOT AN APPLESEED - DO NOT USE THIS SYSTEM WITHOUT A VENT TO THE OUTSIDE.

I think this warning should be made a sticky in the UK forum - how do we go about doing this?

Cheers

24/7

I've added a note to this effect on the opening message.

Thanks for your help,will keep vent open from now on.Any help with the remaining oil?
Many thanks

Graham

I hope you don't think my comments are in any way a critisism of your design - it is excellent and was the inspiration for my own processor. You did show the vent clearly in the pdf of the layout and in a subsequent photograph. If people would read your postings and understand them fully, there's no problem. Unfortunately, most of the info on the infopop board and in written work, focuses on the Appleseed design which does recommend closing the vent when reacting........
...... play safely....

24/7

No trouble!

Good point made. Rather be cautious than careless.

Vino

Sounds to me like your conversion went OK.

BD will always look cloudy immediately after the reaction.

Your BD will be cloudy until its been properly washed and dried.

Graham, I remember you saying you used a 5% prewash, do you find the glycerine is any runnier?

I can only get hold of NaOH locally, not sure if this would be a problem.

Hi Chester,

Yes, remains liquid longer too.
I only use NaOH.

regards,