ivanzyt
Industrial
- Feb 2, 2011
- 1
I am working on an application for a customer that is looking to deploy a 2 stage gas cooling system. The first stage is a adiabatic quench system that will take the gas from dry to saturated thus cooling it in the process. This is the easy bit which I've already speced up.
They then want to cool the now saturated gas stream with a secondary fine water mist spray. This will essentially be direct cooling by conduction between the cool spray and the saturated gas.
I'm trying to work out how mcuh water they need to spray an what droplet size.
My thinking is as follows.
The cooling mist is simply a heat exchanger between the hot saturated gas and the cool water mist.
For any two substances there is a coefficient of heat transfer which is
C= Watts/A/T
Where A is the surface area of the spray
T is the temperature differential between the spray and the hot saturated gas.
I'll need to look up what C is but I'm guessing its going to be close to that of water
I I know the flow rate of the gas and the dimensiosn of the cooling chamber I can work out the dwell time of the spray in the chamber and if I know the sauter mean drop size and flow rate I can thus calculate the surface area of the cooling spray present in the chamber.
The temperature differential will be the average of the initial differential and the 0 differential required at the end of the process i.e. when the cooling mist and the hot saturated gas are at equilibrium.
With all this I should be able to work out the required droplet size for a given flow rate of fluid.
I've not designed on the these systems myself so was wondering if the general approach above was sensible or whether I'm missing something obvious.
They then want to cool the now saturated gas stream with a secondary fine water mist spray. This will essentially be direct cooling by conduction between the cool spray and the saturated gas.
I'm trying to work out how mcuh water they need to spray an what droplet size.
My thinking is as follows.
The cooling mist is simply a heat exchanger between the hot saturated gas and the cool water mist.
For any two substances there is a coefficient of heat transfer which is
C= Watts/A/T
Where A is the surface area of the spray
T is the temperature differential between the spray and the hot saturated gas.
I'll need to look up what C is but I'm guessing its going to be close to that of water
I I know the flow rate of the gas and the dimensiosn of the cooling chamber I can work out the dwell time of the spray in the chamber and if I know the sauter mean drop size and flow rate I can thus calculate the surface area of the cooling spray present in the chamber.
The temperature differential will be the average of the initial differential and the 0 differential required at the end of the process i.e. when the cooling mist and the hot saturated gas are at equilibrium.
With all this I should be able to work out the required droplet size for a given flow rate of fluid.
I've not designed on the these systems myself so was wondering if the general approach above was sensible or whether I'm missing something obvious.