Nanofiltration system expands production & reduces water consumption
A medical device manufacturer in the United States wanted to expand production capacity without exceeding discharge limits that could result in crippling financial penalties. A city mandate of 10% reduction in water consumption for industrial users challenged the plant’s desire to expand, as water discharged from its operations was already rapidly approaching discharge limits. Additionally, it wished to drastically reduce its raw water requirements and waste disposal cost of operation.
The plant was producing a waste stream of 375 gal per minute (gpm) containing organic and inorganic manufacturing byproducts, which contaminated the process waste stream. Historically, this process waste stream would be sent to a waste treatment and disposal process. A significant reduction of this waste stream was required to facilitate plant growth without expanding the waste discharge.
Real Depth of Solutions
Evoqua Water Technologies was chosen for this project based on its extensive process knowledge, piloting capacity and full complement of filtration technologies to allow a comprehensive, integrated treatment package. Of five membrane design options provided by Evoqua, a nanofiltration design employing a packaged nanofiltration system—the Vantage Series M86 System—was selected for piloting based on specific organic and ionic rejection characteristics and cost-efficiency of operation.
The design solution was piloted for an extended period of time to verify its capability to effectively remove the organic compound, maintain acceptable operating characteristics and avoid excessive cleaning or fouling. Additionally, the system would selectively pass a specific inorganic compound that was injected upstream and utilized for manufacturing. By not removing this inorganic constituent, the company could avoid the cost and complexity of reinjecting this pretreatment chemical.
Real Results for Real Impact
After installation and piloting, the nanofiltration system proved to be the best-suited technology for this wastewater stream recovery and reuse, performing exactly as designed and predicted. The new system successfully recovers 80% (300 gpm) of the 375 gpm complex waste stream, producing a new permeate stream that is superior to the plant’s feed water system. This eliminates 300 gpm of feed water requirements and the need to dispose of 300 gpm of a complex waste, saving the plant more than 52 million gal of feed water per year and lowering waste disposal by more than 52 million gal per year. Furthermore, these improvements allow the plant to achieve its requirements to reduce water consumption by 10%, while still expanding production of medical device products.
The plant’s water reuse system saves approximately $3.36 million over a 10-year period. These savings do not include the regulatory penalties avoided or the financial impact of the facility‘s inability to grow in production capacity. The tremendous success of this system has resulted in multiple duplicate or closely related system designs around the globe for this progressive pharma manufacturer.