Water. desalination + reuse

business | 8 | Desalination & Water Reuse | November-December 2014 Green engineering firm scores offshore desalination funding Renewable engineering company 4NRg has won £42,000 in funding for its development of a prototype mechanical offshore desalination unit. The grant from the European Supply Chain innovation for Offshore Renewable Energy (SCORE) programme is to develop a pioneering desalination unit that requires no electricity. 4NRg's unit will harness the mechanical wave or tidal energy to create fresh drinking water. The system is suitable for remote areas making it particularly appropriate for the renewables energy sector, the manufacturer said. 4NRg business development director, Mark Aspinall, said: "If all goes to plan this unit could also be widely used in disaster areas where fresh water is often a scarce, yet crucial, resource." The next step for 4NRg is to scale the prototype up to be tested independently for its commercial potential. This pilot project is planned to take nine months, with the first scaled-up device ready for testing in three to six months, either in a large testing tank or in the sea. Clean water for offshore sector engineers and other workers spending long periods of time offshore has either to be transported out to sea in large tanks or generated at the offshore site, the manufacturer said. Both these options are often costly and inconvenient. 4NRg anticipates growing demand for its plant as wind farms are built further from the shore to access higher-speed, more stable winds. The SCORE programme delivers a £2.5 million funding investment through the European Regional Development Fund. CoNtRaCt&teNDeRNeWs Oasys bags China's first zero discharge contract Massachusetts-based Oasys Water has claimed its recent contract to supply a forward osmosis brine concentrator to a fossil-fuelled power plant in China as a groundbreaking application for the technology. The membrane brine concentrator (MBC) will treat wastewater at a rate of 650 m³/d from the 1,320 MW, coal-fired Changxing Power Plant in China's northern Zhejiang province. The wastewater is from flue gas desulphurization (FGD) in which sulphur oxides are stripped chemically from a power station's exhaust gases. The MBC incorporates Oasys' forward osmosis process to concentrate further the reverse osmosis reject from a total dissolved solids level of 60,000 mg/l to about 280,000 mg/l. This, according to Oasys, is the first commercial power plant application of the technology in a zero liquid discharge (ZLD) system. Oasys's forward osmosis process has been used to concentrate oil field brines in Texas' Permian Basin and shale gas fracking liquid in Pennsylvania's Marcellus shale. FGD has become mandatory for coal-fired plant in China since the introduction of stricter air pollution regulations and estimates suggest the installed FGD capacity in the country could double by 2020. But increasing water scarcity has stepped up the need for FGD wastewater treatment, Oasys said. Oasys' chief executive officer, Jim Matheson, said he was excited about his company's prospects for capturing a significant share of the resulting ZLD market. "The Changxing project is a promising model to showcase the merits of our MBC technology," he said. Oasys' MBC uses a proprietary, high-salinity, ammonium bicarbonate draw solution and a patented semi-permeable membrane. The salinity gradient between the draw solution and the reverse osmosis concentrate generates the osmotic pressure to drive water across the membrane while rejecting up to 99% of the dissolved solids. The diluted draw solution is re-concentrated continuously in a recovery system where draw solution solutes are removed by thermolysis at 70°C and the resultant low-TDS water is returned to the RO feedwater. This lowers the RO system's operating pressure which reduces the treatment train's energy consumption and capital cost. The winning bid was evaluated against six other offers, including those from three of the largest brine concentrator evaporator suppliers said Oasys. Inexia wins US$ 8.6 million Bahrain desalination contract Bahrain's Arab Shipbuilding and Repair Yard company (Asry) has awarded a US$ 8.6 million contract to Gulf Marketing House to complete and upgrade a reverse osmosis seawater desalination plant at Asry's yard in the Bahrain capital, Manama. Under the build-operate-transfer deal Spanish engineering firm, Inexa, will construct the plant. Gulf Marketing House has contracted Inexa to supply all technical resources and equipment required for the upgrade and to commission the 7 Ml/d plant. "The plant will be built according to the latest, state-of-the-art water desalination technology by Inexa, a technical partner of Gulf Marketing House," said Asry chief executive officer, Nils Kristian Berge. He emphasized that the plant would be run on a commercial basis.

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