Estimate water dissolved in hydrocarbon 1

[DianeW]

I am trying to determine the amount of water that will dissovled in hydrocarbon (jet fuel range) at high pressure, like 400 to 1000 psig. I have HYSYS simulation program at work and it is telling me that at 1000 psig and 500 F, the liquid hydrocarbon phase has as much as 20wt% dissolved water. It is quite a bit based on conventional thinking.

I am wondering if any guru out there may have some good info to help me figure this one out. Thanks in advance.

 

[DickRussell]

500 F is quite an extrapolation of most data upon which a correlation may have been based. A quick look at a chart in the 1982 version of the API Technical Data Book sitting on my shelf (a bit dated) shows a curve for kerosine going up to 500 F. The value is 0.27 mol fraction water, which would be on the order of 3% on a weight basis. Many software packages have used the kerosine curve for general application to hydrocarbon systems. The real solubility is somewhat dependent on molecular type within the mixture. On that same chart I mentioned, there are short curves for JP-4 and JP-3 fuel, stopping at 150 F. The JP-4 curve extrapolates to 0.03 mol fraction, an order of magnitude less than for kerosine. Hopefully some better versed in solubility will respond.

 

[owg]

I have some graphs from John J. McKetta who published a lot of work on the solubility of water in hydrocarbons. The solubilities are for various cuts, at various temperatures, "under the equilibrium vapor pressure... for the co-existing phases". For a kero/naphtha cut of MW=150 and at 400 deg F, the top end of the graph, the wt% water in hydrocarbon is about 1.8 and the the mole% water in hydrocarbon is about 15%.

HAZOP at

http://www.curryhydrocarbons.ca