When salt is removed from seawater in desalination plants, the byproduct is – not surprisingly – a lot of highly-concentrated salty brine.

Ordinarily, this is just dumped back into the sea, which can harm the environment. Thanks to a new treatment process, however, that brine could actually be used to desalinate more water.

Developed by a research team at MIT, the proprietary system incorporates what are described as “well-known and standard chemical processes.” These include a nano-filtration process to initially remove unwanted compounds from the brine, followed by one or more stages of electrodialysis.

As a result, the brine is converted into useful chemicals such as sodium hydroxide.