Pairing a chiller w collectiin need some advice on jacketed capacities

Agree with @Dred_pirate’s questions: what kind of “capacity” are you asking about? Happy to help with calculations any day of the week but what are we calculating?

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Im asking the liquid capacity of the jackets.

i already have an AI -40 48L recirculating chiller keeping my dual 50ft coils cold in bath. Im trying to size out chiller for collection was gonna go w a polyscience heated refrigerated 28L -20 -to 105 on 12x28 collection. Next step will be finding a chiller adequete to cool a 200lb solvent tank without 3 phase electricity. First step of this journey i need to determine the capacity of jackets or a calculation on how to do this. So the question is:

How to determine jackets liquid capacity to size the resevoir capacity needed of recirculators.

Also is the heater in 1500w poly gonna be enough heat to create vapor for two cmeps?

Thanks everyone for ur input!

Fill them with water and record how much you used.

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From your answer im gonna assume that theres no industry standard to making/sizing these jackets? Guess filling with water is easy enough.

Ding ding ding

You can calculate it as @TheGratefulPhil directed fairly easily, certainly filling it and finding out by experimentation will get you a more precise result. I don’t think the volume of your jackets is relevant for the bath size of your circulator. You an attach a million liters to a 30 liter chiller if you want to and it will still work. The real question is how many watts/BTUs do you need to achieve some amount of flow at some temperature using some solvent.

On the heater, Google says the latent heat of butane is 165 btu/lb and 1500w is 5116 btu/hr, meaning you can boil about 31lb of butane per hour. Or 1/2lb per minute. That’s assuming no loss or gain to the environment and the latent heat varies slightly by pressure. Also not sure which variety of tane you are running because that affects the latent heat as well

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You also need that same amount of energy to condense that you are boiling off. Probably more coming out of two pumps.

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Yep, roughly the same amount of energy as the heater plus the work done by the pumps. So if a CMEP draws about 750w, you’d need 2250w of cooling at whatever the saturation temp of the discharge pressure is. Rough numbers.

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This seems to be a common misconception.

The size of the reservoir on the circulator is of very little (if any) relationship to the volume of the loop being cooled.

What matters is Watts! (you might find being able to convert other units like Btu or AC tons useful too).

You figure out how much cold you need based on how much solvent you’re trying to cool/condense. There are calculators to help.

The ULTIMATE chiller calculator thread

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Hmm. Looks like adding the 2nd cmep is gonna be a lot of extra load on chiller. Currently running one cmep into 2 coils then into recovery tank. I keep water temp at about 94 degrees via a hottub (not an element in a bucket, an actual hottub) and 40ft run w 3/4 garden hose from sump pump, direcrly into collection jacket. By end of recovery my chiller has gone done to -25. The plan was to add another cmep and make collection a 12x24. I incorrectly figured adding a 2nd pump would offset the increase of collection from 12x16 to 12x24 . Screenshot_20200924-180605_Samsung Internet|236x500

That link was excellent. Thanks for info it makes a lot more sense to determine it like this.

The big thing I would suggest is to stage the discharge chilling. If you can dump some of that heat using something like a tap water waster (fancy word for hose to drain) and then cool the solvent further with the chiller afterwards, you can reduce the BTU requirement of the chiller. I’ve always wondered if a BPR to increase the discharge pressure, allowing condensing to happen at higher temps would be effective. It would shift the load to the pumps though which might not be the right way to go

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You can get jacketed radiators for the cmep’s that help alot just running ice water thru them, that will take alot of your heat out if adding another one.

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This is my current Cooling capacity: 6300 BTU / 1588 Kcal/h / 1846W. What is a BPR?

Where are those jacketed radiator sold at?

A back pressure regulator is a valve that maintains upstream pressure at a fixed value. This is non-traditional and I’ve never heard of anyone doing it but the idea is this: you can compress the tane up to around 45 psi and it will condense at 30C. Go up to 55 psi and it’s 36. If you can maintain that discharge pressure and condense the tane between the pump and BPR, you can use water in a kiddie pool to provide all the BTUs you could ever need. Then when it expands into the recovery tank you’ll get the bonus temp drop from expansion cooling. The downside is that the pump will be doing more work than it otherwise would, meaning it will likely be the limitation. Also BPRs aren’t all that inexpensive.

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Ecogreen has them on there website

Industry standard for creating rated jackets would include the volume on the name plate. Its part of the ASME process for certifying your tanks. Also - the jacket volume is included on industry standard drawings. If you have either the name plate or the drawings of your tank you can get this information and use SidViscous link to dig out the rest for your specific process.

If you don’t have a certified tank - the only process I’ve found that works good is what Dred_pirate recommended. I cannot tell you how many times I’ve had to fill up tanks, jackets, and hidden piping to be able to calculate volumes. Its amazing what people won’t write down that they should some times. Now any time I do new construction or retrofits, I make sure everything gets photos, with checks on sizing with drawings. I want all of my customers to have what they need for future improvements, you know?

Sure hope you get it settled out. And I’d love to see pictures with a kiddie pool… you know for posterity. :smiley:

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So i ended up going with a polyscience 6860T 1.5hp durachiller to keep recovery cold seems like good specs at 0-10c 4400 watts or something… I used to have my coils in a recirculating AI ethanol chiller but I need to build or purchase a heat exchanger. What is proper way to size the heat exchamgers? I

m running 66lbs of gas per run. Im heating at 2500watts + two inline cmep ea with dedicated sieve and dedicated recovery tank…