Hi everybody, I’m currently trying to figure out the right size cooling tower to buy for my condenser on my evaporation skid. Ive got a 2,000,000 btu boiler heating my ~300 gallon reactor to evap ethanol, so for my condenser I’m thinking I need a 3,000,000 btu cooling capacity cooling tower to keep up with 500-700 gph evaporation rate. Originally I thought 150 tons of cooling capacity would do it, but since Im at 5000 ft elevation I believe I need an extra 50 tons of cooling (200 tons total) which is 3,000,000 btu. Anybody have any input on if that size cooling tower will do the trick? P.S. Im not trying to spend 100k+ on a chiller for this. Thanks in advance!
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You should run your alcohol tincture through the first condenser. This will preheat the feed and reduce your energy needs on second stage condenser
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Why would you need to upsize a cooling tower at altitude? Doesn’t water evaporate faster at altitude for a given temperature or am I missing something?
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I doubt you will be able to hit that boil off rate with a 2,000,000 unless you have zero inefficiency’s in your system. but if you are able to transfer all of that energy into the Reactor you will need a 200 ton cooling tower. ebay has used units.
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Usually cooling towers refers to a liquid to air heat exchanger. They are often used with refrigeration systems but are only a component. Your post is a little confusing because we aren’t sure if you just need a heat exchanger or if you need a refrigeration system. What is your required operating temp?
Needs a cooling tower…
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So, usually I’ll post the math for chiller sizing, but this is much more involved. The heating and cooling dynamics at this level are much more involved and using ideal equations can lead to big miscalculations.
If you pay me, I’ll size it for ya—it’d probably take me a few hours.
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yep, better find yourself 200 tons of chilling.
what kind of surface area and ports are on your condenser?
what is average ambient temperature? recovery at pressure or vac?
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That’s not exactly true. The most efficient way is actually a mixture of both water and air heat exchange. I worked on yachts for a few years and it was all liquid heat exchange (obviously no cooling tower because there was the ocean). My biggest wonder is what type of pump would be used for the tower in this instance. I have just recently gotten into cooling and heating mechanisms for extraction and it’s pretty fascinating.
its a shell and tube about 5 ft tall, 5" in diameter. The company that put the evap skid together for me sized the condenser to handle the capability of 700 gph evap and condense.
Ambient temp of the EtOH vapors I would imagine are around 70-80 celsius, I will be putting under vac for sure, Im currently tryingt to decide which vacuum pump to get, can spend up to 10k on the vac ideally
The engineer at CTS in Macon, GA that sells the cooling tower Im looking at that is a 200 ton for 23K$ asked me what elevation and said I need to add 50 tons to account for it, not sure why
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I figured 1,600,000 would hit 500 gph, so went with a 2,000,000 btu boiler. The company that put the evap skid together for me said it should do the trick no problem. The plan is to feed 1 gallon of “juice” in while 1 gallon of EtOH comes out
Whats your price?
Rather than most efficient, I’m going for the cheapest way to handle this load which is definitely a cooling tower, the only power is for the fan on top and a water pump and it only costs 23k vs a chiller that would cost 150-200k$
In a perfect world yes, but that’s not the one we live in lol. Your gonna have losses in the lines and inefficiency’s in the heat transfer in the evaporator. Plus flow rates of the heater water will affect boil off rate as well. I would say if your 70% efficient at transferring the energy your doing great. My conservative guesstimate would be that you will hit somewhere between 400-500gph depending on the rise in temp. I would be very curious I’ve the condenser it self would handle that flow rate and btu load. My condenser is 8” in diameter and 48” in length and I believe it’s only rated to 1.2 million BTU’s.
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Cooling towers the way to go man for sure. I’ve run chillers, liquid to air sealed cooling systems, and cooling towers. Cooling tower al the way!
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How about you post some pictures and more information. How many ft above sea level sir?
I really appreciate your insight! The boiler will be right next to the evap and I’ll be buying the best insulated piping possible and will do my best to make it as efficient as possible. Sounds like I may have to put a bigger condenser on the skid! lol
Yeah ive been using cooling towers for 2 years now, chillers just dont make sense for condensing EtOH lol, wayyyy to expensive
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Pretty sure JedClampet just answered my questions, but thanks for joining! im just outside Denver, so like 5000-5280 ft