Evaporative condenser working with propane/butane

First you need to know the Specific heat of the propane, the mass of propane the compressor can pump and the temperature rise through the compressor. The calculation is in two parts Sensible heat and Latent heat

The Sensible heat formula is BTU = MTS

where M = Mass of propane in Lbs

T = Temperature rise through compressor ( you may need to calculate this using the heat of compression figure for propane) in degree F

S = specific heat

The latent heat content, you simply multiply the mass as above by the latent heat of vaporisation for propane.

Add both together and it will give you a total heat of rejection you can convert your BTUs to Kw if you require. You then give the information to the evaporative condenser manufacturer who will also require the dry and wet bulb design conditions for the area where the unit will be sited. Hope this helps. Good luck

Phill.

Hello philiplyon,

Thanks for your answer. I already done this calculations.

I usually works with this kind of condenser with ammonia. I consult to the manufacturer of the condensers that we sold, but they don't have any experience.

I will try with another manufacturers, like Evapco or BAC.

Thanks again!

Best regards.

Hi,martinobrusa,

you mean that " How to calculation the heat out-put from compressor? isn't that? Pls send me the detail data, I will help you for this matter, may you need some simulation software (i.e ProII, HTRI) to solve it.

With experience in some refrigerated storage tank project (basic design) I think, I can do something for this matter

Hello Doan Ngoc Son,

Thanks for your answer.

What I need is calculate the total heat rejection of an evaporative condenser, which usually works with ammonia, working with a mix of gasses, mainly propane.

In other terms, I want to know the average heat transfer coefficient, "U" for this type of condenser, to input in the formula Q = U x S x LMDT, where:

Q = Total heat

U = Average heat transfer coefficient

S = Heta transfer surface

LMDT = logaritmic mean delta temp.

Best regards,

Martin.

Hi Matin,

In process view of point, this is easy to made the calculation,

The total Heat is depending on the inlet condition of fluid from compressor (such as fluid physical property, flowrate, P, T..) and the outlet condition, which you want.

The average heat transfer coefficient are function of type of H.E(Condenser), it's material (CS, stainless Steel...) and physical property of fluid...

Let find out the GPSA data book (volume 1 section 9) for more detail of calculation.

In case of you want to get the detail design for this matter, pls send to me the detail input data, I will help you to calculation and design it. Pls be noted that, everything is free..hi..hi