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Creating drinking water as a byproduct
June 4, 2007

Over the last several days, we have received three press releases from General Electric about their reverse osmosis equipment to desalinize seawater for drinking purposes. It's no surprise that two of them will be installed in Saudi Arabia and Dubai, countries long on energy but short on water. The stories are compelling in that this technology seems ready for commercial use, even though it still might not be the most cost attractive alternative except in these more extreme applications.

The third story is more interesting in that the desalination operation is part of a chlorine refinery and the drinking water is essentially a byproduct. This project is located near Johannesburg, South Africa, and will be the first of its kind in that country. The primary product is the high concentration brine stream from the RO units which will be used to provide 630,000 tons of ultra-pure salt annually for the production of chlorine, caustic soda, and hydrochloric acid. The fact that they get 70,000 cubic meters (18.5 million gallons) of drinking water every day is almost a bonus. Actually, the value of the water and high-purity salt support each other and mitigate the total cost of the project, estimated at $220 million. That water will go a long way supporting the 150,000 residents surrounding the plant. Water scarcity is a serious problem in that part of the world.

"Reclaiming salt from the desalination brine stream not only improves the overall economics of the refinery project, but also removes logistical issues by ensuring a reliable and locally available supply of high grade salt for use in the refining of chlorine," says Earl Jones, general manager, GE water & process technologies. "Our customer, Straits Chemicals, has an exciting vision for infrastructure development in South Africa, and we are excited to contribute great technology and innovative solutions in support of this vision."

During plant construction, 600 jobs will be created, and the plant will employ around 250 on an ongoing basis. The plant expects to go online in late 2009. It sounds like a good deal for everybody involved. Kudos to General Electric.

We have commercially viable technology to drink seawater. All we need now is a commercially viable scrubber to break carbon dioxide into coke and oxygen, and a handy unit to separate water into hydrogen and oxygen. Something that runs off solar energy would be nice. Contact me if you have any ideas. We will share the profits.

Posted by Peter Welander on June 4, 2007 | Comments (0)