May 9, 2015

MIT comes up with solar desalinatin machine

Daily Kos - MIT engineers have invented a new desalination machine that runs on solar energy. The project began in 2013 when the engineers went to India with the hopes of helping poorer villages and townships with their drinking water.

Business insider - The group came up with a method that uses solar panels to charge a bank of batteries. The batteries then power a system that removes salt from the water through electrodialysis. On the most basic level, that means that dissolved salt particles, which have a slight electric charge, are drawn out of the water when a small electrical current is applied. In addition to getting rid of salt (which makes water unusable for crops and for drinking), the team also applied UV light to disinfect some of the water as it passed through the system.


Anonymous said...

In addition to getting rid of salt (which makes water unusable for crops and for drinking)

I don't think extracting salt from water "gets rid of" it. In fact, I always wonder what we'd do with all the salt if desalinisation became commonplace. I believe there's a certain lake out in the western US that underwent a natural desalinisation by evaporation, and now goes by the name of Great Salt Lake, a tourist attraction that will forever be "unusable for crops". How much of that can we do artificially before we poison too much of the land?

Anonymous said...

I read many years ago that the salts left over from desalination processes can be combined with other minerals to produce bricks, blocks, and similar building and paving materials.

Anonymous said...

If it's sea water that is being used in desalination, then why couldn't the waste salt be returned to the sea? As long as the salt is returned in a fashion that avoids too high a salt concentration in any single area, and the process does not turn the salt into something noxious, then returning the salt to the sea seems less harmful then trying to store it long term on land.