Half-Pipe Jacketed Batch Reactor

[RJB32482]

Hello,
I am looking at an existing half-pipe jacketed reactor and seeing if we can perform the exothermic reaction in it and provide enough cooling. My question is what parameters would I need to calculate the heat transfer from the vessel to the jacket? Also, any calc methods in Process Heat Transfer by Kern to help me out? Didn't see any for the half-pipe jackets in there at first pass.

Thanks.

 

[mechprocess]

I'm working on one also. Kern has a great example of a pipe in pipe exchanger but none for a half pipe although the theory is the same. I used the pipe in pipe method to do my half pipe analysis. Use the hydraulic diameter to calculate the Reynolds number for pressure drop and use the equivalent diameter to calculate the Reynolds number that is used in the Sieder & Tate Equation for heat transfer coeff., and note that the wetted area for heat transfer will be based on the perimeter of the half pipe coincident to the tank wall. Other than that, you can find formulas in mathcenral for archimedes spiral lengths and for helix lengths in mathworld.

Getting the jacket film coefficient is the easy part.
I need help on the tank film coefficient. My tank is not mixed with a mechanical mixer. Do you have anything related to turnoveres per hour and film coeff.?

 

[StoneCold]

RJB32482
This is what I would suggest. Exothermic reactions in batch reactors are usually performed in a semi batch method. Meaning that one reactant (usually the limiting but not always) is fed slowly into the reactor. The exotherm and the pressure are monitored and the feed rate adjusted accordingly. Dumping both reactants in and letting it run is what kills people.
If you still want to calculate the heat transfer capability of your reactor I would suggest running a heat transfer test by heating and cooling water and running the numbers on that.
If modeling the reactor is still what you want here are some articles on the subject. Most of them I got from other theads on eng-tips.
Heat transfer in agitated vessels Chemical Engineering April 4 1983
Simplified Equations for Jacketed Reacot Design Chemical Engineering July 1999
Heat transfer in Agitated Jacketed Vessels Chemical Engineering January 1999
Predicting Heating and cooling Times Accurately Chemical Engineering November 1993
Heat transfer Coefficients and Jacket Flowrates Pfaudler Corporation.

Goodluck
StoneCold