Following the recent news that it had won contracts for four new build-own-operate produced water treatment projects in the US oil and gas industry, Boston-based Gradiant announced that it is currently developing six brine concentration projects in China. Two of the projects are said to be in the final stages of negotiation.
On the eve of his sixth trip to China during the last twelve months, Gradiant CTO Prakash Govindan told WDR that the company is working with Shanghai Electric, a Hong Kong and Shanghai listed state-owned enterprise and one of China’s largest industrial equipment manufacturing conglomerates, to secure the contracts. He said that the cooperation stems from a strategic investment that the company made in Gradiant earlier this year.
“Besides designing and manufacturing power generation, transmission and distribution equipment, Shanghai Electric has an auxiliary equipment group that offers a wide range of products, including thermal desalination technology. Their engineers fully vetted our CGE [Carrier Gas Extraction] process and recognized that it has significant cost advantages over more traditional brine concentration or ZLD technologies,” said Govindan.
CGE is a humidification/dehumidification process that uses air as a carrier gas operating in a closed loop to extract water from a high-TDS wastewater. Water is separated from the impurities by using it to humidify the carrier gas stream. Purified water is then recovered from the gas in a subsequent dehumidification process, which employs a unique bubble column heat and mass exchanger.
“We are now pursuing CGE projects together in China to treat power plant FGD wastewaters and oilfield produced water with distillate capacities that range from 500 to 36,000 m3/d [0.13 to 9.5 MGD]. This compares to our largest US installation, which has a production capacity of 2,000 m3/d [0.53 MGD],” he added. “Even though Shanghai Electric is an investor, we are working together on a non-exclusive basis and our plans are to manufacture the CGE systems in the US. It is, however, possible that some future projects could be manufactured in China.”