SBIR-STTR Award

Ultrasonic PVDF In Commercial Membrane Systems Reduces Fouling for Efficient Water Reuse
Award last edited on: 2/8/23

Sponsored Program
SBIR
Awarding Agency
EPA
Total Award Amount
$600,000
Award Phase
2
Solicitation Topic Code
20-OSAPE-1B
Principal Investigator
Chris Jones

Company Information

Pure Blue Tech Inc

2815 Elliott Avenue Suite 100
Seattle, WA 98121
   (206) 802-2711
   info@purebluetech.com
   www.purebluetech.com
Location: Single
Congr. District: 07
County: King

Phase I

Contract Number: 68HERC21C0036
Start Date: 3/1/21    Completed: 8/31/21
Phase I year
2021
Phase I Amount
$100,000
Membranes are the gold standard for water treatment and reuse. However, membrane fouling inhibits flux, wastes energy, requires cleaning and replacement, and disables concentrate recirculation. Pure Blue Tech proposes ultrasonic PVDF transducers be embedded within membrane systems to reduce fouling. This innovation has potential to transform the economics of membrane operations and water reuse. Pure Blue Tech will develop the approach of integrating PVDF transducer into layers of the membrane system. Ultrasonic wave energy is non-intrusively applied to the operating membrane, preemptively mitigating fouling before and while it occurs by disrupting cake layer formation, organic and biological fouling, particle agglomeration, salt and silica precipitation, and concentration polarization. The goal of this new approach is to reduce attenuation, power intensity, system complexity, and costs relative to traditional attempts that used thick PZT transducers. In Phase I we will place thin, flexible PVDF transducers close to the membranes in a minimal ratio for flat-sheet crossflow cells and plate-and-frame systems. We will then design a spiral wound element configuration and calculate its technical and operational potential for the target market, Wastewater Reverse Osmosis (WWRO). WWRO is a cornerstone for water reuse. Municipal and industrial element sales in 2018 totaled about $200 million, constituting about 10% of the total membrane market. This innovation can retrofit existing or new build membrane-based water reuse systems. Our target municipal customers are city and county wastewater treatment plants with WWRO systems or plans. Our target industrial customers are plant owners and operators at companies committed to reuse, sustainability, and process improvements. For wastewater installations mat tolerate filtration and chemical cleaning cycles, the payback may be as short as one year because cleanings have multiple costs including power, downtime (production loss), labor to clean, chemical cost, cost of disposing chemicals, and shortened membrane life if the chemicals are harsh. Relative to current technologies, PVDF ultrasound has potential to eliminate or reduce the need for MF /UF pretreatment systems. If successful, the capital cost of the overall systems could be cut up to 50%. This would save tens of millions of dollars for a large municipal WWRO facility and space would be reduced by almost half. Environmentally, we recognize benefits including reduced cleaning chemicals and reduced discharge volume. Reducing fouling may enable recirculation of concentrate because membranes can withstand higher feed concentrations. Thus, this technology can minimize concentrate while generating product water that properly removes salts, organics, chemicals, and pathogens.

Phase II

Contract Number: 68HERC22C0035
Start Date: 1/1/22    Completed: 12/31/23
Phase II year
2022
Phase II Amount
$500,000
Ultrasound generated by polyvinylidene fluoride (PVDF) transducers effectively reduced membrane fouling in Pure Blue Tech Inc.'s EPA SBIR Phase I project. This innovation is of paramount importance to all membrane separations applications because fouling is the chief problem and managing it is the dominant focus of membrane operators. Reducing membrane fouling by integrated ultrasound can shift membrane economics, boost production, enhance efficiency, reduce cleaning, and potentially reduce waste volume. Membranes are the gold standard for water and wastewater treatment and reuse applications including food and beverage, microelectronics, power, extraction, automotive, and textiles. The value to United States include water security, ecological health, energy efficiency, and global competitiveness. The U.S. Water Reuse Action Plan (WRAP, Action 7.5) acknowledges this innovation to advance water reuse. In Phase I, Pure Blue Tech proved the concept by embedding a PVDF ultrasound transducer within a benchtop cross-flow cell and simulated plate-and-frame equipment and conducting fouling studies to measure the technology�s relative benefit. Compared to current approaches to reduce membrane fouling, this ultrasound generation approach can reduce fouling up to half. Relative to historical attempts that thick lead zirconate titanate (PZT) transducers and high-powered drivers, this approach reduces attenuation, power intensity, system complexity, and costs. In Phase II, Pure Blue Tech will develop, manufacture, internally test, and pilot field test commercial-scale membrane elements with commercial-quality thin, flexible PVDF transducers. Spiral wound reverse osmosis membrane elements and hollow fiber ultrafiltration membrane elements for wastewater treatment and water reuse will be evaluated for flux, rejection, fouling, net economic savings, manufacturability, maintenance, and reliability. Wastewater reverse osmosis (WWRO) is a cornerstone for water reuse. Municipal and industrial element sales in 2018 totaled about $200 million, constituting about 10% of the total membrane market. This innovation applies to both the new build and retrofit water reuse markets. Our target municipal customers are city and county wastewater treatment plants with WWRO systems or plans. Our target industrial customers are plant owners and operators at companies committed to reuse, sustainability, and process improvements. For wastewater installations that tolerate filtration and chemical cleaning cycles, the payback may be as short as one year. Relative to current technologies, PVDF ultrasound has potential to eliminate or reduce the need for expensive microfiltration (MF) / ultrafiltration (UF) pretreatment systems. If successful, the capital cost of the overall systems could be cut up to 50%. This could save millions of dollars for a five million gallon per day (5 MGD) municipal WWRO facility and would simultaneously reduce space requirements by almost half. Environmentally, benefits would include reductions in cleaning chemical usage and discharge volumes, thus enabling minimal liquid discharge (MLD), a common goal of corporate social responsibility (CSR) and sustainability departments