Building an IC69 Heat Exchanger

[gholladay]

Ya'll welcome and that reminds me that I keep forgetting to post the results of our counter flow heat exchanger at the butane injector, using N2 as the coolant.

We were able to clean a $1500 Apex counter flow exchanger donated to the cause by Permaculture, by pumping solvent through it, and we ran it on Joe's WolfWurx Mk IVB with great success.

We likes it a lot with N2 vapor from liquid on the cold side!! Thank you Permaculture!!

I have metric fitting ordered to fit the counterflow exchanger I found on e-bay for $199, and will follow up with it once we receive the fittings from Swageloc.

Wahoo!! Sounds awesome. I think I'm going to get on board with the counterflow option as soon as I can. Seems like a winner.

Did you guys use a regulator on the exit of the counterflow coil to control the flow of N2, or did you just crack the tank valve as needed?

GH

 

[HG23]

Excellent news about the counter flow exchanger! I am also very interested in making the change from DI to LN2 for cooling.

GW, it seems I've heard that regenerating the vapor head in a liquid nitrogen dewar is kind of a chore once it's been used up so I'm glad you've had success with the liquid phase. What has been your experience regenerating the vapor head?

 

[Gray Wolf]

Excellent news about the counter flow exchanger! I am also very interested in making the change from DI to LN2 for cooling.

GW, it seems I've heard that regenerating the vapor head in a liquid nitrogen dewar is kind of a chore once it's been used up so I'm glad you've had success with the liquid phase. What has been your experience regenerating the vapor head?

Joe just cracks the liquid valve and spits a mixture of gas and liquid. He isn't running a back pressure regulator, and the discharge end of the exchanger is open to atmosphere, so the system pressure seeks its own level.

It doesn't take much, so Joe says he's never had head pressure issues. When called upon, the vaporizer can easily build pressure faster than the flow rate his system requires. He indicated that he usually only uses it on frosty mornings, and otherwise mostly ignores it.

 

[pbard1]

Joe just cracks the vapor valve and spits a mixture of gas and liquid. He isn't running a back pressure regulator, and the discharge end of the exchanger is open to atmosphere, so the system pressure seeks its own level.

It doesn't take much, so Joe says he's never had head pressure issues. When called upon, the vaporizer can easily build pressure faster than the flow rate his system requires. He indicated that he usually only uses it on frosty mornings, and otherwise mostly ignores it.

Could you please explain the spitting of gas and liquid?

I shoot optical fiber using N2. Have never seen it spit

Am considering going the N2 route. Could use an little more info on specific hardware setups users are utilizing.

Thanks

 

[Gray Wolf]

Could you please explain the spitting of gas and liquid?

I shoot optical fiber using N2. Have never seen it spit

Am considering going the N2 route. Could use an little more info on specific hardware setups users are utilizing.

Thanks

Let me start out by explaining front paw/brain disconnects and acknowledge a typo, which I corrected to say liquid valve, instead of vapor valve, so it probably makes more sense.

The gas exits the dewar as a liquid, but flashes off in the tubing to and through the heat exchanger, so that what exits the counter flow heat exchanger discharge, is a mixture of gas and liquid.

A simple flow through, without back pressure regulator.

 

[Gray Wolf]

Joe is using a salvaged counterflow heat exchanger from a Apex CO2 unit, donated by Permaculture and we are getting quotes for having custom ones wound, but in the interim are playing with two units similar to this one, though we are using stainless Swageloc compression connectors, not brass hose bibs.

http://www.williamsbrewing.com/STAINLESS-CONVOLUTED-COUNTERFLOW-CHILLER-P3452.aspx

Connection to the dewar is insulated stainless tubing with compression fittings.

 

[gholladay]

Looks sweet GW!

GH

 

[pbard1]

Let me start out by explaining front paw/brain disconnects and acknowledge a typo, which I corrected to say liquid valve, instead of vapor valve, so it probably makes more sense.

The gas exits the dewar as a liquid, but flashes off in the tubing to and through the heat exchanger, so that what exits the counter flow heat exchanger discharge, is a mixture of gas and liquid.

A simple flow through, without back pressure regulator.

Thanks GW.

Makes a lot more sense to me. Tried similar using dipper CO2 tank. Used too much gas from a 75# tank to make it worth the trouble.

What size dewar are you using? Rep told me the capacity was approximately 16x that of 200# tanks I was using for blowing fiber.

I guess they deliver..

 

[Gray Wolf]

Thanks GW.

Makes a lot more sense to me. Tried similar using dipper CO2 tank. Used too much gas from a 75# tank to make it worth the trouble.

What size dewar are you using? Rep told me the capacity was approximately 16x that of 200# tanks I was using for blowing fiber.

I guess they deliver..

Like this

 

[pbard1]

Like this

GW, what size tubing are you using for your liquid to gas phase change. When I was running liquid CO2, I used a 1/4 line to run to my exchange bath. In the bath (Alcohol), I coupled to a 1/2" copper line, about 12' long. I had mixed results; with the desired cooling effect, but also had issues with CO2 snow constantly building up in the line. Also blew thru a tank of gas way too fast. After that experience, I shelved the idea.

 

[Gray Wolf]

GW, what size tubing are you using for your liquid to gas phase change. When I was running liquid CO2, I used a 1/4 line to run to my exchange bath. In the bath (Alcohol), I coupled to a 1/2" copper line, about 12' long. I had mixed results; with the desired cooling effect, but also had issues with CO2 snow constantly building up in the line. Also blew thru a tank of gas way too fast. After that experience, I shelved the idea.

1/4" stainless N2 lines and 3/8" heat exchangers. It doesn't turn to dry ice.

 

[pbard1]

1/4" stainless N2 lines and 3/8" heat exchangers. It doesn't turn to dry ice.

Thanks for your input.

Who would have thought the the thermodynamics class I took 25 years ago would have been useful for anything other that figuring why my inflatable boats got limp after putting into the lake...

 

[HG23]

How is the counterflow heat exchanger working out for Skunk Pharm?

 

[Gray Wolf]

How is the counterflow heat exchanger working out for Skunk Pharm?

Joe is loving his on liquid N2, running 50/50% mix.

 

[cyclopath]

It pays to read...

It pays to read...

I wish I'd gotten here a tad earlier.

I purchased an MT69 with my TR21, and built the MT6900 (50' 3/8" coil with valves and pressure gauge) about a week later.

So much for inventing a wheel.

Self draining would have been a nice touch.

 

[cyclopath]

Although now that I've traded the TR21 for a CMEP-OL I might have to use it as an injection cooler.

 

[maxinum]

Joe is loving his on liquid N2, running 50/50% mix.

thanks for all the great info built my mk4 from icmag may be some one can help me been doing dri ice with a ic69 I'm going to try Liquid N2. I'm not sure ? can you use a nickel brazed plated heat exchanger for sub zero butane or are the plates to close to gather for the butane move thew at-0f ? or is a ss counterflow coil heat exchanger better? thanks all & GW

 

[Gray Wolf]

thanks for all the great info built my mk4 from icmag may be some one can help me been doing dri ice with a ic69 I'm going to try Liquid N2. I'm not sure ? can you use a nickel brazed plated heat exchanger for sub zero butane or are the plates to close to gather for the butane move thew at-0f ? or is a ss counterflow coil heat exchanger better? thanks all & GW

I prefer a counter flow because of their higher pressure rating and lower probability of a leak, but haven run a plate exchanger in our application to see how it flows at zero.

Over the years in industry, I don't remember ever having lost a tube exchanger, but have suffered plate exchanger failures.

 

[HG23]

Is it very loud to run the counterflow exchanger?

 

[Gray Wolf]

Is it very loud to run the counterflow exchanger?

It isn't excessively loud to run butane through one side and liquid N2 through the other on the Mk IV test sled and it would be quieter with a process chiller.

With the liquid N2, pharmer Joe is just cracking the liquid valve on the Dewar, so that liquid starts in one end and gas, with some spitting, comes out the other as it absorbs heat from the system and vaporizes.