Tesla has developed a patent for a waste water treatment system that could pave the way for more cost savings in operational expenses.  

The patent, titled System for Regenerating Sodium Hydroxide and Sulfuric Acid from Waste Water Stream Containing Sodium and Sulfate Ions was recently published and details how the system utilises membrane concentration systems as a cornerstone to develop a system where waste water is treated and possibly even reused.

In its patent description Tesla explains that common processes used in manufacturing often see large quantities of wastewater being disposed of, a practice it notes is both expensive and harmful for the environment.

How it works

The electric car maker describes its system in the following description:

“As compared to prior waste water treatment systems, the waste water treatment system of the present disclosure uses the three dedicated membrane concentration systems to maintain high ion concentrations in the feed and low ion concentrations in the product chambers.”

“The first thermal concentration system takes in the dilute acid produced by the electrolysis treatment system that allows pure water to permeate while the dissolved acid species are rejected. The pure water is recycled back to the second chamber of the electrolysis treatment system to dilute this stream, while the reject concentrated acid is extracted as a product.

“The second thermal concentration system takes in the dilute caustic produced by the electrolysis treatment system and allows pure water to permeate while the dissolved caustic species are rejected. The pure water is recycled back to the third chamber of the electrolysis treatment system to dilute this stream, while the reject concentrated caustic is extracted as a product.

“The membrane concentration system takes in the existing waste water that still contains significant dissolved sodium and sulfate. Pure water is extracted as a product, and the concentrate reject is sent back to the electrolysis treatment system waste water feed to maintain a high concentration of sodium and sulfate ions in the waste water feed.”

Further cost savings

With such a system in place, Tesla expects to see optimizations in its operations. The Silicon Valley-based carmaker noted in its patent that its waste water treatment system would likely even extend the lifetime of components such as the AEM and CEM, resulting in more cost savings.