Wastewater Recirculated to the Chiller Or Tower Loop

Before governments began monitoring wastewater"In addition to the extreme black water on install, it
discharges and long before it was popular to bewas determined that fusaria and nematode
"green" in your process, a Swedish company namedinfestations to the cooling trough water existed as
Wirsbo partnered with a Minnesota based waterloading dock doors allowed these common spores to
treatment company to solve both a processenter the open trough water on each robotic
wastewater problem and develop a system to reuseprocess line."
the process water.Wirsbo implemented programmable controllers and an
Wirsbo, founded in 1694 in Sweden is most famousionization test on every shift to prevent recurrence
for its world leading in floor radiant heat tubing.of the microbes.
Wirsbo manufactures its tubing through a roboticGlass media was implemented in 2006 at flow rates
extrusion process, cooling the tubing in water troughsof 60 GPM to 400 GPM to further lower microns of
fed 24/7 by the robots. Because of the highfiltration and maintenance cost. Filtration has evolved
temperature, and the open air trough, the coolingfrom bag to DE, DE to Zeolite, Zeolite to Glass over
water in the trough was black and oily, with a burningthe 13 year site history, with Glass media extending
odor. The trough itself had string algae 1-2" thick onboth media life and reducing backwash by 50%. The
the sides. Minnesota Water Treatment arrived withglass media is used in Pentair TA 60, TA 100 and TR
ionization and oxygenation technology in 1996 to140 low pressure, high flow rate sand filters with high
design and develop a chemical free system.flow rate valves. Two years without re-bedding is
Wirsbo has a 50 year warranty on their tubing, thenow historical.
use of chlorine or other chemicals degrade the life ofThe use of ASAHI differential pressure valves has
their product. Tests after cooling, in chemicallyallowed a headered bank of filters to automatically
treated water were employed and were the same.shift filters for backwashing at the convenience of
Chemicals were not an option!on-site personnel. Previous bag filter systems did not
Minnesota Water Treatment not only solved thepermit the recirculation and rinse of the water and
"black water" cooling trough issue, a recirculationwould shut down flow in the troughs requiring
strategy was ultimately developed allowing water tocleaning or change out to continue manufacturing
recirculate through 60 ton EVAPCO cooling towerstubing.
and chiller bundles in later years.