DIY Saltwater Survival Bottle (Compact Desalination Kit)

Any water we harvest in the wild should be purified. But what do we do when the only water available is saltwater? In this video, NightHawkInLight explains how to make a DIY saltwater survival bottle.

This portable desalination kit will make short work of converting saltwater to freshwater by capturing steam. The steam is concentrated through cooled, copper coils and the result is pure, distilled water. Here’s how to make it…

Equipment

• 1 stainless steel, non-insulated water bottle with metal cap
• 4 feet of flexible ¼” copper tubing
• Right angle brass compression fitting with ¼“ openings
• Plumbing solder (lead free)
• Soldering flux/paste
• Fine grit sandpaper
• Butane torch for soldering
• Drill
• 1/4” drill bit
• 1/16” drill bit
• Pipe cutter

Directions:

1. Remove the metal cap and any rubber or plastic gasket on the cap
2. Drill a ¼” hole through the top of the cap
3. Drill a second hole with the 1/16” bit between the hole in the top and the rim to let heat escape while soldering
4. Cut a length of copper tubing that will emerge ½” from the top and bottom of the cap
5. Cut 2 small pieces of solder and wrap them around the tubing on the top and bottom of the lid
6. Coat the solder with flux and melt to solder to create a weld
7. Solder and seal the 1/16” hole
8. Reattach the gasket after the cap has cooled and screw the cap back on the bottle
9. Attach the right-angle brass compression fitting to the tube at the top of the cap
10. You can insert a rubber gasket into the fitting to create a watertight seal to use the bottle as a conventional water bottle
11. Take the copper tubing and wrap it tightly around the bottle 8 or 9 times
12. Bend the top of the tubing up along the bottle and the other end down along the sides of the bottle
13. Remove the coiled tubing and attach one end to the brass fitting and tighten
14. Remove the rubber stop gasket from the brass fitting if installed
15. Fill the water bottle with saltwater and suspend the bottle of over an open fire or a fire contained in a can or hobo stove
16. Set a container at the other end of the tubing protruding away from the water bottle
17. As the water begins to steam it will condense in the tubing and begin to drip fresh water into your container
18. To better condense the water, immerse half of the coiled tubing in a pan or can of cold water so the bottom is surrounded by water or wrap the coils with a continuously wet rag
19. Stop the process before the bottle is empty so you don’t concentrate salt and minerals on the side
20. Add a splash of the saltwater to the distilled drinking water to provide electrolytes
21. You can also use a solar reflector oven to heat the bottle but paint the bottle black

Watch the video below to see it done.