Here's a simple, compact, efficient condenser which can be made in a couple of hours.

Plumber's Delight Condenser

This message has been edited. Last edited by: GrahamLaming,

Smashing the inner tube is brilliant- I have made lots of these without doing so, but commercial counterflow heat exchangers are set up with flutes in the inner tube.

For those in the USA, there are two kinds of reducer fittings and one is easier to work with than the other. Some of them have a ridge inside which is supposed to prevent the tube from passing all the way through the reducer (in regular plumbing, you never want to turn a pipe in on itself, which is what we essentially are doing when building these).

The other available style of reducer has just a little 'bump' inside which prevents the tube from passing through. These are available at Lowes usually. They're the type you want- file the ridge off with a small chainsaw file, and your tube should now pass all the way through so as to make building the tube-in-=shell heat exchanger possible.

These were about $40 at current copper prices when I last built some 4-foot-long ones.

Thanks for that great info.

I used your idea to make a similar design, except I used a 2" DWV PVC pipe as the outer cover (I don't have knowledge or tools to do the plumbing with solder, etc. )

I used 2" becuase I have a stick of it spare, and some drum bungs which I used to reduce the 2" Wye connectors to 3/4". But it could be done with 1" pipe, even 3/4 maybe, and probably save some money becuase the ends wouldn't need the adapters I used.

Also, I made it 7 foot long. The 1/2" copper pipe was the most expensive - $14 at lowes for 10 ft. I have yet to use it, but I think it will do well. The crimping of the pipe is genius! Love it!

If there is interest, I can post some pics and parts list.

I used the same design as the OP: 1/2" copper pipe with a 3/4" water jacket. The only difference is I packed the column with copper scouring pads insted of crimping the pipe for better condensation.

That would help create turbulance in the vapour but not in the cooling water.

Hi Paul,

If you could put together a list of parts and a 'how to', I'm sure others would appreciate it.

Not everyone is a fan of soldering, and if you are all going lead-free in the States, as we are in the UK, soldering is becoming a lot more of a challenge if you've only got a simple propane torch to heat with.

The melting point of today's solder is a lot higher than the solders of last year and before, now that the lead content has been completely eliminated.

quote:

Originally posted by Ant:
That would help create turbulance in the vapour but not in the cooling water.

Not so. The "wet" side of the copper tube is just as deformed as the inside. The water will not form smooth non-turbulent laminar flow along the pinched pipe.

Of course, if you could somehow deform the outer pipe as well, that would be swell, but overkill I think.

Finest regards,

troy

I was talking about the copper scouring pad packed column, compared to the pinched pipe which would of course cause turbulant flow in the water as well; that was my point really.

quote:

Originally posted by Ant:
I was talking about the copper scouring pad packed column, compared to the pinched pipe which would of course cause turbulant flow in the water as well; that was my point really.

Dear Ant,

How atypically unobservant of me. You are entirely correct in your analysis. I will read more carefully in future.

Thank you for pointing out my error.

Very finest regards, as always,

troy

Graham, I wanted to let you know that your "Plumbers-Delight compact condenser" is a big success. I did the 2 stage base/base process. I used 22% methanol and 5g/l NaOH in 100L of dried oil that titrated at 3.4g/l. I did 80% in the first stage and 20% in the second stage. I ran stage 1 for 1 hour and drained about 5gal of glyserol off. started the pump and put in the remaining methoxide and ran the pump for another hour and shut it down for the night. In the morning I drained off another gallon of glyserol.
I then started the heater and turned the thermostat all the way to 150F. The methanol started to run! I have a 1/4 inch steel line mounted in a brass compression fitting sticking straight down into the BD with a very low setting on the air regulator. It is almost shut off. The temp went to 180F without the heater on. The methanol just kept running! It has run for 4 hours and I have collected over 2L of methanol.Is that normal? The volumn has slowed and the temp has come down to 170F. I was pretty excited........Roy

There should have been 3.3 litres methanol in your biodiesel so you 60% of the way there. You need to go hotter to get the more.

neutral, how do you arrive at the 3.3 liter amount? How can I get it hotter? I have a 1500 watt 115v heater element. Should I get a 4500 or 5500 watt 240 v element, and run it on 115v?

Hi bigroy

Glad it's working well for you! The boiling point rises as the concentration of methanol in your biodiesel drops.

Adding more heat energy will help. Keep a close eye on temperature and don't run the process unattended. Make sure all your components can take the higher temperature - tubing, pump etc.

Adding more insulation will help, especially around the top of the condenser and your pipework.

Injecting a VERY slow feed of air into the tank AFTER your distillation has come to a halt, but while still heating and keeping the pump running will also help you to recover more methanol. I inject air into the space at the top of the tank.

If you run a 5500 watt 240V element on 115V you will get only around 1300 Watts of heat power, because power is proportional to the square of voltage. Halve the voltage and you get 1/4 the power.

Some useful links ...

http://biodiesel.infopop.cc/eve/forums/a/tpc/f/4441089311/m/6101057961

http://biodiesel.infopop.cc/eve/forums/a/tpc/f/4441089311/m/3331008071

The condensor looks like a great idea. I am just beginning to process bio-diesel (& forums as well), and have had great success so far.

How much success is there in capturing the Methanol? How much could one exspect to retain? % wise How much water would I expect to use the cool the condensor? How long should I run it? I was wondering what I might exspect if I tried this?

Graham, Are you familiar with our hot water heaters, that we use as a processor? They have (2) elements, one that is low and one that is about 3/4 of the way to the top. We only have the lower one working. The top one is in place but not wired. If I wired the top one, it would only be under the BD a little bit. When the pump would start the BD level would drop. I don't want the element to be out of the BD with methanol vapor present. Got any ideas?

Doyle, the one that I made is based on GL's plan.I used 3/4 copper pipe as the outside water jacket. The condenser tube is 1/2 copper pipe that I crimped at 90 degree intervals the entire length except the ends that slide through a 3/4x1/2x1/2 tee. I have city water and a well for irrigation. I put 5/8 auto heater hose on the water inlet and outlet with 5/8 female garden hose repair ends. I just trickle the water through. It is cool on both the inlet and the outlet. I got 2 liter 380 ml methanol off of 100 liter BD after the glyserol was drained. I use a little compressed air in the vapor area above the BD. I only have a 1500 watt, 115v element in the Appleseed. It worked fine till the % of methanol was lowered and I was not able to heat the BD higher

Thanks bigroy,
It looks like very little water is used. I had thought about routing the water to the wash tank through the condensor. I guess it wouldn't warm the water up enough to really make a difference. What do you use to catch the methanol in as it comes out the condensor?

you are going to laugh! I have a piece of 1/2 clear pvc tubing into a 1 gal milk jug. The methanol is crystal clear and I checked it with a hydrometer to be 97%. I think it has to be able to run without going into a sealed container.......Roy

The condensor is a very elegant solution to this problem. I see from your picture that you are using a Grundfos circ pump for your processor. The choice on this side of the pond has been what to utilize instead of the crap HF pump, which though cheap has many deficencies. I would appreciate your comments on how well the the Grundfos Pump works. They are commonly available not too expensive and a great deal more reliable than the HF. Cheers Dan

Hi Dan

The Grundfoss has been a champ - I'm really impressed with it.

I posted about it recently here.

Good luck!