INTRODUCTION:
Broken
Bag Detectors are also called
Solids Flow Monitor - FM-10).
MOST EFFECTIVE &
ADVANCED TECHNIQUE FOR
A) DETECTION OF A BROKEN BAG in Fluid Bed Drier
(FBD) / Processor (FBP) / Rotary Vacuum Dryer
(RVD), resulting in saving of product losses.
B) DETECTION OF A BROKEN BAG in Filter Bag
House, resulting in efficient pollution and
emission monitoring / saving of product losses
/ prevention of contamination of production
line / preventing damage to downstream equipment.
In all Process Industries where
Filter Bags are used, frequent problems are
encountered due to BROKEN OR TORN FILTER BAGS.
Some of the problems are :
 |
Product losses due to broken / torn filter
bags; |
 |
Emission of solids at levels higher than
that permitted by pollution control / environment
/ health and safety standards; |
 |
Damage to downstream equipment like Fans
/ Blowers / Pumps etc.; |
 |
Contamination of production line; |
 |
Increased production / process down-time; |
 |
Inefficient operations of E.S.P.s, Filter
Bag Houses etc. |
The principal on which
our Broken Bag (or Sieve) Detector works is
as follows
When the drug / product is being dried in the
FBD / RVD, product losses often occur due to
ruptured filter bags. Significant product losses
can occur by the time the filter bag rupture
is detected & the FBD / RVD is stopped.
The Broken Bag Detector is used along with the
FBD / RVD for preventing product losses
due to ruptured filter bags (or broken sieves)
by immediately sensing the leakage
and stopping the motor of the FBD / RVD.
It has been observed that the filter bags are
replaced every 2-3 months to avoid leakages.
BBD can serve as an early warning system
indicating possible failure of bag in the near
future by detecting higher emission levels enabling
the bag to be replaced in time. This is possible
by using an analog output (optional
feature) which would be proportional
to the mass flow of solids / particulates.
This analog signal can be connected to an indicator
or recorder in the control room or to the PLC
of the FBD (as shown in Figure 1 &
2).
 |
 |
FIGURE 1 - TYPICAL ACTIVITY OF
BROKEN BAG DETECTOR |
FIGURE 2 - TYPICAL INSTALLATION OF
BROKEN BAG DETECTOR |
Maintenance costs are reduced
since the downstream equipment such as blowers,
fans etc., are protected from spilling powder.
Labour required for cleaning operations after
bag ruptures is also saved. Above all, bag ruptures
may lead to batch losses, forward
sections of the plant remaining idle, production
targets not being met, penalty clauses
/ order cancellation and lowering of corporate
image which could be avoided by installing the
Broken Bag Detector.
The Broken Bag Detector is highly sensitive
and reliable. It consists of a Sensor with shielded
cable and an Electronic Control Unit. The Sensor
is a 316 stainless steel rod with Teflon Insulator.
The Sensor is installed in the duct of the FBD
as shown in Figure 3.
When the leakage of the product takes place
through the ruptured filter bags (or broken
sieves), the product strikes the Sensor. This
results in the generation of an analog electric
signal directly proportional to the mass flow
of the colliding solid particles. This signal
is then conditioned, amplified & processed
through sophisticated electronic circuitry and
then used to give an alarm and finally to stop
the motor of the FBD / RVD thereby preventing
product losses.
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| FIGURE 3 - FBD WITH BROKEN BAG DETECTOR |
The Broken Bag Detector is not only used in
the Pharma industry, but is also used wherever
an FBD with Filter Bags is used – Chemical,
Fertilizer & other such industries. The
FM-10 is also used for other applications like
monitoring the flow of materials from hoppers
/ silos / bins / any type of vessel to the downstream
equipment & giving an alarm in the event
of failure / stoppage of the flows.
The FM-10 has several inherent
advantages
 |
The only device based upon direct measurement
of quantity of solids / particulates. |
 |
Price wise it is the most economical
device. |
 |
It has no moving parts & thus, it
is very versatile, robust & maintenance
free. |
 |
It helps prevent costly drug losses and
also saves time & labour required for
cleaning operations which are required after
any bag rupture. |
 |
With a meager investment, the device
can enable you to prevent production loss,
down time & penalties arising out of
atmospheric contamination. |