EDITOR’S CHOICE
SUBMERSIBLE SOLUTION
ALTRA
SUBMERSIBLE GEARED MOTORS SOLUTION FOR STATE-
OF-THE-ART WASTEWATER TREATMENT PLANT
Conducting an effective and up-to-date
wastewater treatment service is challenging.
When a plant in the Netherlands needed
to renovate its systems in one of its post-
sedimentation tanks, it chose Bauer Gear
Motor to provide a durable, submersible
solution.
The Hague,
Netherlands. One of
the plants, located
in Houtrust, covers
5 hectares and, on
average, can treat
nearly 79,000 cubic
metres of waste water
a day.
Delfluent Services BV is a consortium
of specialised companies working on
wastewater treatment facilities in The Hague,
Netherlands. One of the plants, located in
Houtrust, covers 5 hectares and, on average,
can treat nearly 79,000 cubic metres of waste
water a day.
The treatment process at Houtrust begins
with the removal of large, solid material.
Subsequently, the wastewater goes through
pre-sedimentation tanks, activated sludge,
biological treatment and post-sedimentation
tanks.
The wastewater treatment plant was originally
built in 1967 and needed to be refurbished
to be in line with current environmental
regulations. Included in the maintenance
project was the replacement of a gear unit
that was used to drive the chainwheel in
one of the sedimentation tanks. The original
equipment gear had always required a high
degree of maintenance, demanding the
tank’s basin be emptied twice a year to carry
out regular services. This level of ongoing
maintenance resulted in production losses
and high maintenance costs. Delfluent chose
to use the refurbishment as an opportunity to
upgrade the system to a solution that could
be easily maintained.
The original supplier had designed a solution
which employed a single stage bevel gearbox
fully submerged in the water. A connection
tube was used to connect the gearbox to
the rest of the power train, positioned above
the water level. The tube connected to a pre-
stage gearbox and an overload coupling, with
a 0.55 kW motor driving the application.
In order to replace the existing motors and
gears, Delfluent contacted Bauer Gear Motor,
worldwide supplier of high quality, reliable
geared motors, and part of Altra Industrial
Motion Corporation.
Bauer has a proven track record of developing
geared motors for challenging conditions
and was particularly suited to help design a
44
PECM Issue 38
Below, Specific
advantages of the BK
series include: simple
and cost-effective
installation together
with submersible
options in compliance
with IP68.
replacement to the original equipment. In
particular, Bauer produces IP68-rated versions
of its motors, which are fully submersible and
impervious to water and dust ingress.
To provide the optimal service, Bauer
conducted the replacement operations with
its strategy partner Vos Gekas & Boot (VGB),
expert in rotating equipment, including
pumps – a supplier familiar to the wastewater
treatment facility where the activity took
place.
The solution provided by Bauer consisted
of a drive belonging to the BK series of
bevel geared motors (type BK70G20X-
82W/DHEU09SA4/SP) that can operate
continuously underwater. This motor series
is available with power ratings between 0.03
kW-75 kW and operates at 110-690 V and
50/60 Hz.
From two one-stage gears, Bauer moved to a
multi-stage geared motor. The bevel gearbox
range can withstand torque of 80 Nm up to
18,500 Nm and gear ratios of 3.67-108.60 for
two-stage gears or 7.29-441.3 for three-
stage gears. In this way, the equipment was
simplified, making future maintenance easier.
In addition, by removing the gear, the
tube and the coupling, Bauer reduced the
oscillations in the system and provided a
more energy efficient solution.
Specific advantages of the BK series, besides
IP protection against dust and water, include
simple and cost-effective installation, high
energy efficiency, robustness and durability,
low maintenance requirements and low
running costs.
This particular application runs at a set speed
and so there was no need for a variable speed
drive that might prove advantageous in
other situations. Using a lower power-rated
0,37kW IE2 direct on line (DOL) motor offered
the most energy efficient and cost-effective
solution for this application.
Ferry Spaans, Project Leader, Innovation
Projects at Delfluent Services BV, commented:
“Our main goal at Delfluent is to develop,
refurbish and manage wastewater treatment
plants in The Hague. The wastewater
treatment plant in Houtrust has been
operating for 50 years and has been
renovated three times since then. Now,
thanks to Bauer, we can continue providing
an optimal service, treating the waste water
flow from the homes and companies in The
Hague with an innovative solution.”
For further information visit
www.altramotion.com