Does it have to be batches?

Can't it be like the reverse of a rocket engine where they use regenerative cooling from the fuel to cool the rocket nozzle, but just in reverse.

Or like they way my grandpa was doing moonshine -- the alcohol vapors pass through a serpentine in a water tank, condense, at the end you obtain alcohol, the water in the tank gets warmer -- instead, heat water coming from the water cooling tank that is preheated by the vapors of water that is condensing in the serpentine pipe.