After several years of looking for a logical and practical system, we
feel we have finally found it! This system is based on the high performance
of a remarkably inexpensive filter cartridge, Harmsco
Poly- Pleat TM. In the past, you would have
to spend ten times the cost ($150.00 per 10” length or $35.00 per
sq ft) for an equivalent performance. Now, with this filter cartridge
as the foundation, it’s practical to provide barrier filtration
with filter cartridges.
Included in the system are: an optional Repressurization Pump, Pressure Transducers,
Pressure Gages, optional Automatic Switching Duplex and either Parallel or
Series Operation.
The entire system does not have to be used, as shown below. In
many cases, one or two phases may be eliminated. For example, the
duplex feature can be optional, as can the use of a prefilter housing,
depending on the water quality. Each system varies slightly due
to changing conditions of your water source. Some systems will
require duplex automatic switchover to maintain flow rates. Other
systems do not require a prefilter because of the extreme cleanliness
of the water or low water use. Still other systems can be run without
a pump; they simply use the pressure available from the water source.
First, we can help determine specific requirements by pilot scale testing
to decide if these filters are practical and efficient for your water
supply. Lastly, we will determine whether your need requires prefilter
housings and a duplex system as shown in the system above.
A Practical Solution
Finally, there is a practical, inexpensive solution for surface
water or ground water under the influence of surface water, requiring
barrier filtration to meet SWTR (Surface Water and Treatment Rule)
requirements. In 1996, the EPA approved legislation establishing
more stringent standards to control giardia cysts, cryptosporidium
and other common drinking water contaminants.
One application requiring treatment, is high water consumption
on a clean supply. A slow, sand filter is ineffective, because
the organic digestion layer cannot build on the upper surface;
the water is too clean. Since the water is so clean, under these
circumstances, it is practical to consider using disposable cartridge
filters. Disposable filters will not be plugged by particles in
the water. However, you still need barrier filtration as mandated
for surface water and ground water under the influence of surface
water.
Absolute rated POLY-PLEAT TM cartridges meet the 99.9% removal
requirements mandated by SWTR. These cartridges consist of a pleated
polypropylene filter media which provides a greater surface area
for longer filter life and increased particle removal. The end
caps, media and center tubes are one integral component for added
strength and seal.
Another application would be if the water has some of the typical
contamination associated with surface water or ground water under
the influence of surface water, but the use of the water is not
high enough to warrant a full scale capital approach. For example,
seasonal use: campsites, trailor parks, small hotels and condominiums.
These low intensity uses can now be treated inexpensively and practically
with this filtration approach.
The System