Re: Flash Evaporation?
The larger ships have dry exhaust up a stack. Your sailboat will not. The ships run the engine all the time (or at least a large diesel electric gen set), your sailboat will not (hopefully!!). The ships have acreage to spare for an engine room, your sailboat does not (or if it does, we NEED pictures!!!!).
The biggest problems I see are redesign of the diesel exhaust system and real estate dedication in the engine room.
The biggest advantage to an RO watermaker is that you can add it to an existing cabinet space without a complete mechanical redesign of the existing systems and pipe the water to and from it. It is an easier add on. If you are starting with an empty shell of a hull and designing the mechanical systems first, then you have a shot at making this work.