This represents a vast improvement, GE says, since bottling companies can typically use 75 to 85 percent of the water supplied to their treatment room for bottled water and soft drinks. The rest is discharged as a waste stream.
A major global beverage company in Asia used GE’s AquaSel non-thermal brine concentrator technology in the pilot. The system runs at a very high recovery on reverse osmosis reject water, producing a clean filtrate stream plus a small blowdown stream and a dry salt cake for disposal. The filtrate produced has total dissolved solids at or below the levels found in the raw water, and can be looped back to the front of the ingredient water system.
The pilot AquaSel system had a capacity of 36,000 gallons per day. In more than 1,000 hours of operation with this system, the bottler was able to capture and convert 1.5 million gallons of what was previously considered a waste stream into water suitable for reuse, with a quality equivalent to that of the incoming water to the plant, according to GE. Less than one percent of the influent water was a byproduct.
Based on pilot results and the increase in the amount of water that could be treated and reused for bottling, GE says as much as 30 million gallons per day could be saved by major bottlers if they used this technology at all of their plants around the world.
GE has also announced a system that it says overcomes a major technical obstacle for larger desalination facilities, by reducing the energy demands associated with pumping water by at least 10 percent.
Water and Sewerage Corporation, a desalination facility in Tarpum Bay, Bahamas, has installed a pilot Integrated Pump and Energy Recovery system (pictured) to further test the technology.
Lower-capacity desalination plants traditionally use positive displacement (PD) pumps because of their high efficiency and availability. These small pumps are based on the use of a fixed geometry and either rotating axial pistons or crank-driven pistons to pressurize water in the chambers.
Larger PD pumps, however, face mechanical challenges. They usually either feature a larger crankshaft or high crankshaft speeds to overcome these. But due to the larger size and operating speeds, these solutions have led to significant vibration and maintenance issues, GE says.