Purifying Water

Most recent answer: 02/05/2018

Q:
How do I calculate whether my idea of converting sea water to drinking water will work? You'll need more info obviously! Cape Town and just North and west of it has icy ocean current passing it. Particularly in summer. The idea is to pump this cold water over steel piping which contains humid air from heated sea water. Seawater heated in shallow tanks and flows to evaporation chamber with transparent roof and conically shaped with a hole at the top with an adjustable speed extractor fan and the humidified air is pushed into the steel piping and will exhaust( have a small extractor fan there too) after water has been condensed out of it. Loads of questions - trying to keep this short - but will be able to control speed of fans, therefore the movement of air. I want to see if yields are theoretically good enough to design a prototype. The technology needs are low and the heating and cooling energy comes from the sun and the sea - as does the water. Cape Town and surrounds is in a devastating drought with Day Zero currently being 19 April, 2018. (Day Zero is when city stops supplying water to our taps!) There are going to be dedicated collection points where you can queue for drinking water! This is no joke. Would appreciate assistance in this project.
- David Mitchell (age 52)
Cape Town, South Africa
A:

Your idea certainly makes sense in principle. Whether the actual costs (initial capital outlays plus energy costs for the various pumps and fans) make it efficient is beyond our ability to answer. You need a good engineer with the right expertise. Perhaps a civil engineer at the University of Cape Town would either be able to help or know someone who could. The motivation is strong!

Mike W.


(published on 02/05/2018)