Heat calculations

In my new colony i want to make a 10 kg/s petroleum boiler. The boiler fuels 5 self cooled petroleum generators, which outputs 3,75 kg/s of pWater at 95°.

I was wondering if one volcano is enough heat alone to turn the pW into steam and back into water? Can anyone take me trough the heat calculations to show average input of magma needed to clean the water?