Hey everybody I have a quick question. I am am wondering if anyone knows how to calculate how much water is evaporating per hour in a given solution.

I am on an rig and we are drilling a hole and i know i am lossing water to evaporation at surface and i would like to calculate an exact figure instead of guessing like i am told to do. So looking around at various websights i found a formula for the rate of evaporation

E=KA(Xs-X)

E= rate of evaportation kg/hr

K=evaporation coeffieceint of

A=surface area

Xs=humidity ratio in saturated air at same temp

x=humidity ratio

Now Since i Have a solution and in fact the water is incased in the mineral oil through the use of an emulisfier i dont think this equation will work. SO how do i calculate it. Right now I am using the change in ratio between the water and the oil. Ie with no additions of water or oil if the ratio of oil to water goes from 70% oil to 78% oil and the water goes from 30% to 22% then we are seeing an 8% decrese in water so therefore i take the system which is x number of gallons and times it by 8% and that should give me the amount of water I lost. is this correct is there a better way.

The solution is 78% mineral oil and water is 22% right now. Now the flow rate of this particular liquid is 732 gpm. The temperature of the solution where it is exposed to air is 150 F.