The water filtration thread got me thinking:
I see a lot of reverse osmosis watermakers, but it's a very energy-intensive process. Why hasn't anyone invented a flash evaporation process for small boats?
That's what the cruise ships use. Waste heat from the engines raises the temperature of the water, and the pressure is reduced until it "flashes" to steam, which is condensed back into pure water. I tried researching how much vacuum would be required to boil, say, 140 degree water. But it's hard to convert the ratings of vacuum pumps to figure out whether this would be more, or less, efficient than reverse osmosis.
If it worked, you could use your waste engine heat while motoring to make pure water.
I see a lot of reverse osmosis watermakers, but it's a very energy-intensive process. Why hasn't anyone invented a flash evaporation process for small boats?
That's what the cruise ships use. Waste heat from the engines raises the temperature of the water, and the pressure is reduced until it "flashes" to steam, which is condensed back into pure water. I tried researching how much vacuum would be required to boil, say, 140 degree water. But it's hard to convert the ratings of vacuum pumps to figure out whether this would be more, or less, efficient than reverse osmosis.
If it worked, you could use your waste engine heat while motoring to make pure water.