bubbler cooling system

[warramungas]

Couldn't you just run water through the tap and run a return hose (pc & rc waste) to the top of the water tank? If you have awater tank tap that is.

[Lowie]

Just need the FSD Eliminator to arrive.

Patience young Jedi. Your first born will arrive in due course.... :teasing-neener: :handgestures-thumbupleft:
Cheers, Lowie.

[Thiele]

interesting...why is the column separation section being cooled? What temperatures are attained across the column length? What difference is made to the final product?

[Zak Griffin]

What do you mean by column separation section? Are you talking about the reflux condenser?

[Thiele]

What do you mean by column separation section? Are you talking about the reflux condenser?

meant the mass transfer section - column section containing the packing

[bluc]

Only things being cooled are the rc and the pc..

[Teddysad]

Up to this stage my cooling has been a recirculating system using 2 x 200l barrels.
A pump in barrel 1 sends the water to the still.
Output from the still ( PC and RC combined via a T junction) then goes to Barrel 2 which is elevated.
I took a hose from the side of barrel 2 about 200mm from the top and as Barrel 2 filled the water flowed down into barrel 1.
This worked well - up to a point. I was running a 25l Alex 25 still with a 1500w element.

With the new FSD 4" SSG column I found that after a few hours of running the water temp crept up.
If I want to do multiple runs I did not want to start with a temp of 30C +

My options were either cooling, running water to waste with a flow from the tap or a bigger reservoir.
An IBC was considered but takes up too much room and my submersible pump (550w) would be a hassle.

I have now added a cooling system to the flow.

I visited a local car wrecker and purchased a radiator complete with fan (cost me $50)

Rad1.jpg

RAD2.jpg

Showing reverse with an outlet hose fitted

Top outlet.jpg

Close up of top outlet. I used an irrigation fitting and the remains of the original radiator hose and 19mm hose - this goes into the barrel.

20170629_170257.jpg

I used the same system at the bottom for inlet although smaller to match the hoses from the still.

This is now set up over a single barrel with the output from the radiator returning to the barrel.

I hooked up the fan to 12v and away she went. Power source = car battery attached to trickle charger so plenty of amps for that fan.


The water exiting the still goes through the radiator, the fan cools it and the water is then returned, cooled to the barrel and temperature remains constant in the system.

Yesterday did 2 runs so about 9hrs total. 200l Water never got above 24.5C and that is chucking 2400w at it.

In addition space taken up by one 200l barrel now available with not a lot of noise from the fan.

One Happy Teddy.

[Yurugaboy]

I discovered that my FSD 4 plate runs very differently if yo swap the supply hose from bottom to top in the condenser.

I swapped them at setup and found my reflux wasn't working and wondered why. I checked the water rate- same slow flow and then checked the hoses . Oops . Once back to supply at bottom I could bring it back to total reflux . Noticed it once before .runs way better with supply from bottom of RC especially . PCalc is not as quirky.

After 4 runs I'm seeing it's foibles . Very cool.

It sits and rocks quietly . Very relaxing .

[bluc]

If you feed water in top it "falls" through if it goes in bottom it sits for a while before draining. The "stationary" water absorbs heat and drags it away :handgestures-thumbupleft:

[db1979]

If you feed water in top it "falls" through if it goes in bottom it sits for a while before draining. The "stationary" water absorbs heat and drags it away :handgestures-thumbupleft:

The reason why we run water in at the bottom is because the cold water hitting the RC has dissolved air which become insoluble as the temperature increases inside the RC. This forms bubbles of air that can accumulate in the RC.
If the water enters at the bottom the bubbles of gas that were dissolved get pushed out of the top. If you have transparent water lines then you'll see the gas bubbles constantly coming from the RC as soon as the RC gets some action.
If the cooling water enters at the top, the dissolved air again becomes insoluble due to the higher temperature, the bubbles of air don't get pushed out as well (the bubbles just float up past the moving water) and you get an RC that mostly fills up with air.
In at the bottom, out at the top, get your water flowing in the direction that air bubbles want to go.

[Yurugaboy]

If you feed water in top it "falls" through if it goes in bottom it sits for a while before draining. The "stationary" water absorbs heat and drags it away :handgestures-thumbupleft:

The reason why we run water in at the bottom is because the cold water hitting the RC has dissolved air which become insoluble as the temperature increases inside the RC. This forms bubbles of air that can accumulate in the RC.
If the water enters at the bottom the bubbles of gas that were dissolved get pushed out of the top. If you have transparent water lines then you'll see the gas bubbles constantly coming from the RC as soon as the RC gets some action.
If the cooling water enters at the top, the dissolved air again becomes insoluble due to the higher temperature, the bubbles of air don't get pushed out as well (the bubbles just float up past the moving water) and you get an RC that mostly fills up with air.
In at the bottom, out at the top, get your water flowing in the direction that air bubbles want to go.

:text-+1:

[bluc]

So getting closer to seeing some bubbles with my bits hopefully arriving before the weekend.
Wondering just how much cooling water temp effects the amount of reflux produced. I am guessing constant water temp is best but how much will a 5-10 degree increase affect things?
Will it result in needing to constatly adjust the needle valve?

[bluc]

Guessing it will be pretty crucial maybe I will run my rc water straight from tap to waste.. :happy-partydance:

[db1979]

This used to be a problem for me until I got my radiator sorted out. I used to discard a portion of the warmer water and replace it with cool tap water. If I didn't I found that tails came on way too soon as the RC wasn't able to keep them back. It doesn't matter for the PC though. You could try running the RC off the tap only as it will only need a trickle. I can't remember who originally suggested this approach.

You just beat me.

[Yurugaboy]

You can still control simply reflux with a few adjustments. In put water from town water has risen over summer so needs closer attention. I just water the lawn with waste.

[bluc]

Yea add more and more flow in small amounts as water warms up...but that sounds like a pain in the ass. Would rather constant temp and more stable cooling. Will look at an ibc but not sure how I would set it up incognito...

[db1979]

sounds like a pain in the ass

Yep.

Did you give up on running a radiator bluc?

[bluc]

Havnt totally decided yet but dont have couple hundred for decent thermo fans to replace the pathetic ones i currently have. Gotta ask does your water increase in temp and is temp stable by time full reflux is finished, then remains stable for rest of run? Was it you that only used 50l water?

[db1979]

I think my temp increases a little but then stays constant. It's all to do with the ambient air temp. It sits a few degrees above ambient. More efficient in winter. I run off about 20 L. I'll put up a thread of my system one day.

Why not just go to a local wreckers? Mine is a twin fan and only cost $50. I bought two 12v transformers (25 amp, 300 W) from www.5stardistilling.com.au for about $20 US each. Hot water from the still in at the bottom and cooled water out at the top back into my reservoir.

[A&O]

I may have a cooling option for people. When I was a service manager at the local JD dealership, I had to solve a cooling issue with the pto dyno. When load testing 400hp, the oil & cooling water certainly get hot quick. We used the big metal fans from Bunnings over the radiators with some pretty rough shrouds made from 20l oil drums and a hundred rivets. Wasn’t pretty but certainly effective. So if your thermos sent cutting the mustard, grab from Bunnings a high flow fan and fashion a shroud out of anything on hand, you’ll be surprised how well it works.