Large-capacity nozzle centrifuge for starch applications0 pages

Large-capacity nozzle centrifuge for starch applications
Merco CH-36B GOF
Alfa Laval separator centrifuges for the starch industry are
available in many different sizes and confi gurations, each
one designed and adapted for dealing with the widely varying
separation tasks required. The Merco CH-36B GOF is a
dedicated starch centrifuge, designed for several applications
in the maize wet milling process.
Applications
The Merco CH-36B GOF is a nozzle centrifuge designed
for continuous discharge of solids. It is used for classifying,
concentrating and washing solids, and for clarifying liquids
that contain relatively high solids concentrations. The Merco
CH-36B GOF is widely used in the maize starch industry for
processes that include primary starch separation, gluten thickening,
millstream thickening and middling concentration.
Standard design
Separation takes place in the bowl, which is mounted on
a vertical spindle. The vertically mounted motor drives the
spindle near the top via two bound V-belts. All metallic parts
that come in contact with the process liquid are made of
high-grade stainless steel. Thirty nozzles are placed in the
bowl periphery at a narrow angle from the tangent, in order to
recover energy from the material being discharged through the
nozzles. The nozzles are made of tungsten carbide, suitable
for abrasive solids. The centrifuge is equipped with sensors
for monitoring the bowl speed, vibration and bearing temperature.
The inlet and outlet devices are equipped with fl anges.
Circulating oil ensures that the bearings are lubricated. An
external pump maintains the necessary pressure.
Special features
The Merco CH-36B GOF employs a special recirculation
system that provides highly effi cient separation. Solids can be
recirculated to the nozzles at the same time as wash water is
added. Working with the underfl ow draw-off valve, the return
fl ow system provides a unique means of controlling the separation
process. It allows the operator to control and optimize
the separation process by determining how much underfl ow
is to be removed, how much is to be recycled back to the
rotor and how much wash water is to be added. This makes
it possible to use nozzles with a large diameter, which allows
variations in feed concentration and prevents blockages.
The centrifuge thus becomes more versatile, and can be
easily adapted to changes in procedure. The Merco CH-36B
Fig. 1 Merco CH-36B GOF with motor
GOF has a built-in hydraulic hoist that eliminates the need
for an external lifting device, and thus reduces the downtime
required for servicing the centrifuge.
Basic equipment
The centrifuge is equipped with a motor, a self-cleaning
strainer for the feed, speed and vibration sensors, oil temperature
sensors for the spindle bearings and the motor winding,
a hydraulic power unit for the lifting hoist, a set of special tools
and a standard set of spare parts.
Options
Control-torque motors of two different power ratings are available.
Frequency drive is also possible. The centrifuge bowl is
available in classifi er (PS) or clarifi er (GT, MST, CL) execution,
with different disc spacings. A double underfl ow outlet is available
for the MST version.