SUSTAINABILITY
PPG filters
Beyond the food sector , the interconnected global supply chain makes all types of industries vulnerable to the dangers of water scarcity . Water is used in the transportation of many foods and goods . Petroleum refineries require large amounts of water to produce petrol and diesel fuels . Energy production and manufacturing rely heavily on water for heating , cooling and cleaning .
Increasing water efficiency
A sustainable approach to water use is vital to addressing water availability and accessibility issues . In order to combat water scarcity , government and industry must work to improve water use efficiency , working toward using less water , and reclaiming and recycling more water after it has been used .
Manufacturing , urbanisation and industrial agriculture are all affecting the way we use water , as well as generating large amounts of wastewater . This is often transported for treatment , further contributing to carbon emissions .
Companies have begun to pursue important environmental , social and governance ( ESG ) goals . In addition to ambitious emissions reduction goals , the reuse of industrial process water and wastewater is a paramount concern and a key enabler of a more circular production process .
Different types of wastewater and final applications require customised approaches that allow fit-forpurpose treatment , from removing bacteria found in greywater ( used water from washing or bathing ) to treating produced water from oil rigs . Advances in filtration technology have made treating and recycling water an economically and environmentally viable option for more businesses and industries than ever before .
Wastewater treatment methods
Multiple methods have been developed to treat industrial wastewater , though they face many challenges when implemented at large scale . Some methods use chemicals , require physical agitation to separate solids and result in sludge that requires disposal .
Other mechanisms , such as chemical precipitation or centrifugation , are useful but still plagued by barriers like high energy requirements , high cost and low efficiency , or incomplete contaminant removal . Oil droplet particles in particular are very small and difficult to remove from wastewater .
Membrane filtration uses permeable membranes to separate solids and free oil from wastewater . Polyacrylonitrile ( PAN ) and polyvinylidene fluoride ( PVDF ) are two of the most common membrane materials , often designed with a
thin cast surface layer that controls porosity . They require low amounts of energy , no reagents , and are highly efficient , but historically suffered from the risk of low flow rates , poor durability and oil accumulation on the membrane known as fouling .
High-flux membrane technology
Recent advancements in material science at PPG have created a high-flux polymeric membrane that features a unique single-layer construction suited for microfiltration and ultrafiltration processes .
The material is a thermoplastic composite made of a hydrophobic polymer matrix and a microporous , hydrophilic , inorganic filler ( Figure 1 ). Proprietary manufacturing processes can adjust the membrane ’ s micro- and ultra-range pore size to fit the needs of the end user .
Unlike some conventional membranes , PPG ’ s unique chemistry has a higher throughput with reduced fouling . It removes free and emulsified oils , soaps , bacteria and suspended solids to less than 10 ppm , demonstrating higher efficiency than PAN and PVDF filters and lower amounts of oils in the permeate and better clarity in head-to-head testing .
The single-layer design results in flux rates that are two to four times higher than conventionally cast polymeric membranes . This design also gives the membrane the ability
JUL / AUG 2023 SPECCHEMONLINE . COM
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