IDM ¦ Technology/IT
Long pre-soak, thorough
cleaning, long hot caustic
spray zone
PAC Global supplied a 10.6 metre long and
1.86 metre wide single-end bottle washing
machine to Oberweis Dairy in North Aurora,
in which 5,000 half gallons can be perfectly
cleaned every hour. Before the bottles are immersed
in the pre-soak, they are emptied of
any residues with absolute reliability. Thanks
to the long pre-soak time, the high caustic
temperature of 80 °C is already optimally
utilised when the bottles are immersed, and
the caustic in the immersion soak is regularly
circulated. This is followed by an extremely
extensive dwell time in the subsequent hot
caustic zone with just under 85 °C and 15 internal
spray tubes. Seven spray zones with 42
stationary, high-volume low-pressure spray
nozzles have an intensive residue removal
effect and guarantee the bottles' perfect microbiological
condition. Finally, there is slow
cooling and several rinsing and spraying with
fresh water. Each bottle is in the machine
for 17 minutes, passes through five stages
of heating and pre-soaking, a long caustic
bath and a long hot caustic spraying zone,
and after washing, six water spraying zones
for cooling. The absolutely clean bottles leave
the machine at around 25 °C. At the same
time, there are always 1,413 bottles inside
the washer. The machine's longitudinal sides
have large inspection windows, and all areas
are very easily accessible for cleaning.
Low energy and caustic
consumption
The very low overall energy consumption of the
machine is the result of the combination of long
The "CB 9-1.89-RV-10.6 Mi ng" from Swiss specialist PAC Global, 10.6 metres long
and 1.86 metres wide, can perfectly clean 5,000 half-gallon bottles every hour
(Photo: PAC Global)
pre-soak, a seven-stage bottle cooling after
hot caustic spraying, and fully insulated hightemperature
zones. The design of the caustic
zones in stainless steel results in a reduction of
the radiant heat by almost 50 per cent. The entire
machine housing is double-walled in all hot
zones (floor, ceiling, side walls, and rear wall)
and insulated with 5 cm thick material. The entire
machine therefore radiates very little heat.
Significant energy savings are also achieved by
the five-stage pre-heating of all bottles before
immersion in the caustic soak and the use of a
small amount of water and caustic (therefore,
heat losses are minimal). In addition, there is
heat recuperation between caustic II and the
pre-warm pre-spray water, compensation of
caustic carry-over by automatic re-dosing of
caustic II, and optimised liquid guidance including
ideal chain guidance, which leads to a reduction
of the connected electrical load.
Excellent cleanliness and spare
parts available at any time
Marty Rodriguez from Oberweis in Chicago
Founded in 1927 by Peter Oberweis in Kane County, Illinois, the company now
includes not only numerous "milk and ice cream stores" but also a hamburger and
pizza chain. The dairy has long relied on returnable glass bottles in various sizes
for its milk, especially for its top and organic products (Photo: PAC Global)
summarises the reasons for the decision
to purchase a new bottle washer at PAC
Global: "The straightforward, manageable
design, the additional, sophisticated mechanical
cleaning through five spray zones,
simple and reliable electrics and electronics.
Added to this are the uncomplicated, globally
available drive units, the full stainless
steel machine with its insulation in the hot
zones, thus low heat emission and thus low
energy consumption. An important reason
for the decision in favour of PAC Global was
the much better support and possibilities
in terms of spare parts and improvements
compared to the previous machine. The entire
process from purchase to commissioning
was not only a business experience, but
also a very cooperative one. We bet on the
right horse, because above all we have perfect
cleaning – even of extremely dirty milk
bottles," says Rodriguez.
Many years of perfect cleaning
PAC Global also attaches great importance to
the machines' service life of decades, an interplay
of compact, completely stainless steel design,
15 mm thick chain guides, extra-strong
main conveyor chains, bottle cell carriers and
bottle cells made of high-strength steel. All
components are easily accessible, the mechanical
structure is clearly arranged, the electrical
system is future-proof, and the control system
is decentralised. The PAC Global principle is:
Electronics as much as necessary, but not as
much as possible. If a single system fails, it can
be easily replaced by a more modern component
even after many years. "Each of our
machines is completely connected to our factory,
we carry out a test run under operating
conditions. Only then will we hand over our
systems to our customers," emphasises PAC
Global owner Günther Zimmermann.
38 · November/December 2020 ¦ international-dairy.com
/international-dairy.com
