A new technology unveiled by GE during early July’s Singapore International Water Week potentially saves millions of gallons of water a day from being flushed down the drain by the world’s beverage makers.
The company recently completed a pilot run of its new AquaSel water treatment system at an Asian bottling plant. During the two-and-a-half-month production-scale study, the technology helped the plant use almost all the water it took in and reduce its liquid waste stream to less than 1 percent.
“This means unprecedented water recovery,” says Juan Alfredo Zepeda, food and beverage industry product manager, water and process technologies for GE’s power and water. “It’s a powerful tool that helps companies use water that they would otherwise send to the drain.”
Companies can use water that they would otherwise send to the drain
Many bottling plants today use reverse osmosis systems to purify the huge amounts of municipal, river or well water they need to produce beverages. That process forces raw water against a membrane that separates out unwanted salts. As a result, about 80 percent of the water that was brought in is cleansed of salts and can be used to make drinks. The remaining 20 percent, waste that contains high salt concentrations, is called brine.
GE’s AquaSel is built to treat the brine, and at its heart is an innovation called a non-thermal brine concentrator (NTBC). It contains two key components, one that removes salt from the brine to recover most of the stream as usable water and a small byproduct of an even more concentrated solution and a second that uses a chemical and mechanical process on the concentrated brine to precipitate salt crystals out of it. The resulting treated water is the same quality as that which first flowed into the plant and is reintroduced into the manufacturing process. Combining reverse osmosis with NTBC allows bottling plants to use 99.5 percent of the water they bring in.
Zepeda says that a typical AquaSel system will be able to process 150,000 gallons of brine per day. Of that, 143,000 gallons of treated water can be recovered and around 7,000 gallons of waste will head to the drain. Traditional water treatment methods currently employed by bottlers would see all 150,000 gallons of brine leaving the plant as waste.
AquaSel’s efficiency upgrades will translate into reductions in a plant’s wastewater volume by 10 to 50 times and its freshwater intake by 10-20 percent.
Another option for bottling plants to avoid dumping the brine that AquaSel treats is to use thermal evaporation to purify it, but this requires huge amounts of energy that is friendly to neither the environment nor the manufacturer’s bottom line.
“Companies today face higher water usage and discharge costs,” says Zepeda. “This technology gives them a tool to meet higher water efficiencies without the capital and energy costs of putting in a thermal system.”
The technology could be useful in petrochemical, wastewater management and water supply sectors
Zepeda says the NTBC technology is the greenest choice for treating brine because it harnesses the liquid’s water chemistry without adding any chemicals in. By controlling only its pH, temperature and other environmental properties, NTBC forces salt crystals to precipitate out of solution.
He also believes AquaSel, which took GE engineers two-and-a-half years to develop and test, could prove useful in fields beyond the food and beverage industry. His group is investigating its potential in the petrochemical, wastewater management and water supply sectors.
Heiner Markhoff, president and CEO of water and process technologies for GE’s power and water business unit, says billions of gallons of water are pulled out of the world’s freshwater supplies needlessly because of technical and economic limitations on bottlers’ abilities to treat and reuse wastewater.
“GE’s NTBC technology can turn billions of gallons of lost water into clean, usable water by virtually eliminating the wastewater streams in a variety of industrial and municipal treatment processes,” Markhoff said in a statement.
Top image: A rendering of GE’s AquaSel system.