Researchers at Purdue University have...
Microbial reduction filtration system provides clean water for summer home in The Berkshires
Otis is located in Berkshire County, Mass., and has a population of 572, according to the 2000 U.S. Census Bureau data. The town is surrounded by several lakes and ponds. Berkshire County, located in the western part of the state, was founded in the early 18th century, prior to American independence. The Berkshires, as the general region is referred to, are the southern continuation of the Green Mountains, which are located directly to the north in Vermont.
The area is highly rural and agricultural, populated with small towns and picturesque villages featuring colonial-era architecture and quaint shops. The area is also famous for its thriving arts scene, with several theater, art, music and symphony venues. The Berkshires are considered one of the most beautiful regions in New England; as such, tourism abounds and summer homes situated around the abundant lakes are common. Few of these homes are connected to any municipal water or sewer system. Residents must rely on wells or surface water for their water supply, and septic systems or more rustic outhouses for their sewage disposal. A typical summer season at a home may run from before Memorial Day until just after Labor Day.
On July 7, 2010, a KX Technologies point-of-use (POU) fibrillated adsorbent cellulose technology (FACT) microbial reduction water filtration system was installed at a summer home located in East Otis.
The home’s water source for the bathroom and sinks is Big Pond, which is situated directly in front of the home. Drinking water has traditionally been bottles of city water brought up on every trip for immediate use.
The filtration system consists of a 30-micron sediment filter and a dual filtration system comprised of a 5-micron carbon block pre-filter and an encapsulated microbial reduction (MR) filter utilizing KX Technologies’ FACT media tested to the U.S. Environmental Protection Agency Guide Protocol.
No other forms of filtration or disinfectants, such as chlorine, were used in this application. The filtration system is located in an unheated open space under the floorboards of the house.
KX Technologies’ FACT Media is made using various adsorbents immobilized by fibrillated nanofibers. The media is produced in a wet laid process, yielding an extremely uniform fabric, where high percentages of very small adsorbents can be efficiently immobilized down to 1-micron average particle size. Smaller fibers produce a larger relative pore area for a given pore size, and most of the fibrils remain connected to the core fiber, reducing material loss. The fibrils reach out from the core fiber and entangle particles and other fibers. FACT media allows immobilization of a wide range of particle types and sizes, and can be formulated for microbiological reduction capability.
The media’s small pore size, coupled with the microbiological chemistry and large pore area, allows for low pressure drop and high activity. Microbiological reduction filters (MR FACT) are constructed to flow under gravity or pressure conditions, and provide high sediment capacity and longer filter life.
Big Pond contains approximately 1.0x106 cfu/100 mL heterotrophic (HPC) bacteria, and free living protozoa such as Chlamedomonas sp, Spirijera, Euglina species. Pond water was pumped through the filtration system at a flow rate of 1.7 liters per minute. After passing 1 gal of the pond water through the system, water samples from influent and effluent were collected in sterile containers and transported to KX Technologies’ microbiological laboratory for microbial testing. Visually, the influent pond water samples looked slightly turbid and yellowish (similar to diluted tea), and the effluent samples looked clear.
The samples were tested for volatile organic compounds and total elements using a GC-MS and ICP-MS, respectively. Samples also were checked for total organic carbon (TOC) using a Shimadzu TOC analyzer. On Sept. 9, 2010, after two months of typical summer use at the house, total filtration through the system was measured at 68 gal; this indicates significant periods when the filters were not in use, increasing the potential for microbial growth within the filter. A second set of influent and effluent samples was brought to the KX Technologies’ microbiological laboratory for analysis. The samples were tested in the same manner described above.
The filtration system featuring the MR FACT media filter removed all of the influent bacteria, thus providing clean, clear and safe drinking water to the homeowner.
At the end of the summer season in East Otis, it was recommended that the filters be removed from the system as the entire water distribution system is drained and closed for the upcoming winter season. Each filter should be replaced with a new filter for the following season’s use.
Author’s Note: The certification achieved by the MR FACT media filter used in this application is conditional upon use with microbiologically safe water. KX Technologies does not recommend using this type of filter or filtration system with water that is not microbiologically safe. Test results in this application indicate the MR FACT media filter is successful at reducing bacterial contaminants.