CASE STUDY
CITY OF MILLHEIM
THE BACKGROUND
For years, the trickling filter used by the city of Millheim had not consistently met the BOD and TSS standards for discharge into the nearby river for several reasons. With a higher than normal influent strength due to the influence of industrial waste streams, it relied very heavily on healthy biomass to produce a clean effluent. In the summer, when the weather was warm, all was well. But in the winter, when the weather contributed to a slow and inefficient biomass, the effluent quality was greatly affected and the system was unable to meet discharge standards.
THE CHALLENGE
To provide a long-term, affordable, and easy-to-operate solution that could withstand the seasonal temperature swings, as well as wide fluctuations in influent from the local industrial facilities – and still meet the stringent effluent standards required by the State.
THE RESULTS
BOD₅
ND
TSS
ND
TN
<5 mg/l
NH₄
<5 mg/l
Location:
Influent:
Effluent:
Capacity:
Year:
Millheim, PA, USA
450 – 1,000mg/l BOD
Non-Detec. BOD
100,000 GPD
2007
FAST FACTS
THE SOLUTION
In 2007, a new MBR plant was built using the patented and proven MaxFlow© membranes from A3-GmbH. Because an MBR operates in a high MLSS concentration (typically 12,000 to 15,000), the system is able to produce and maintain a healthy and robust biomass, even through the coldest of winters.
As a result, the Millheim MBR plant has consistently produced a high-quality, superior effluent over the past seven years, regardless of the temperature or weather conditions.