Scientists figure out new way to remove salt from water

91

Brine water produced by the oil and gas industry contains even more dissolved salts than ocean water, and is a growing environmental concern – but scientists have figured out a new way to treat it.

These hypersaline brines can pollute the fresh water resources which communities depend on, and are difficult to treat.

But a team of engineers from Columbia University in the US say they have now developed a radical new approach to desalinating them.

Image: Hypersaline brine can poison natural water sources if it is left untreated

The method, known as "temperature swing solvent extraction" (TSSE), involves mixing the hypersaline brine with an amine solvent.

Scientists say the method can desalinate very high-salinity brines, up to seven times the concentration of seawater. This is more than both the method currently used for seawater desalination, known as reverse osmosis, and the water evaporation method can achieve.

Advertisement

The method was published in the scientific journal Environmental Science & Technology Letters.

Once it is mixed in the brine, the solvent, which is less dense, is lifted to the top of the brine.

More from Science & Tech

Amine solvent. Pic: Jane Nisselson/Columbia Engineering
Image: The method uses an amine solvent. Pic: Jane Nisselson/Columbia Engineering
Hypersaline brine. Pic: Jane Nisselson/Columbia Engineering
Image: Hypersaline brine is added to this solvent. Pic: Jane Nisselson/Columbia Engineering
The fluids have different densities. Pic: Jane Nisselson/Columbia Engineering
Image: The solvent absorbs some of the water. Pic: Jane Nisselson/Columbia Engineering

The mix is then placed on a room temperature bath to help complete the water extraction – and after that the solvent is decanted from the mixture.

A warm water bath then provides a temperature swing which de-mixes the processed water from the solvent – because the solvent is less able to hold water at higher temperatures.

When the solvent releases the water, it sinks to the bottom of the bottle – from where it can be collected.

Pic: Jane Nisselson/Columbia Engineering
Image: The solvent releases some of the water due to the heat. Pic: Jane Nisselson/Columbia Engineering

Read More – Source

[contf] [contfnew]

Sky News
[contfnewc] [contfnewc]
You might also like

Comments are closed.