Every
plant has a unique system for collecting and separating gases
and dust
during the melting operation. Conventional systems typically
include a single radiation detection system with a large volume
of scintillation material located in a strategic location on
the Off Gas systems screw conveyor.
With a single radiation detector the false alarm rate will
be high unless the systems sensitivity (detection capability)
has
been decreased significantly. In addition, with a single radiation
detector there is only one alarm signal. This is not enough
information for personnel to make an instant decision on
what steps should
be followed for the alarm condition. Stopping the melting process
and evacuating personnel is a big critical decision that has
to be made very quickly. It is therefore just as critical that
the person making the decision have as much information as
possible regarding the status of radiation level at multiple
points on
the Off Gas/Dust collection system.
RadComm
has addressed this problem and has taken a different approach
to monitoring
the Off Gas/Dust Collection system for
radioactivity. With our RC/300 detection system design the
customer can configure the system to suit the requirement of
the application. For example, with the RC/300 we utilize multiple
detection units situated at strategic points on the Off-Gas/Dust
Collection system System Layout and Detector Mounting Locations).
Each detector assembly includes state-of-the-art scintillation
material and electronic hardware that allows maximum detection
capability to be achieved for low level radiation emissions
in a Dynamic and Static mode. The assemblies will be connected
to a central detector controller via low voltage signal cable
where all signals are processed at an extremely high sampling
rate allowing detailed statistical analyses to be performed
on each detector signal. From the data analyses, the “Lowest-Achievable-Alarm-Level” (LAAL)
is set on an automatic continuous basis. The Detector Controller
can simultaneously monitor up to 4 detector assemblies from
a distance of up to 300 meters away. The detector controller
will be coupled to a Central Control Console (mounted in an
occupied area) via low voltage signal cable or by wireless
communication (optional). The Central Controller will include
an illuminated display readout, keypad, alarm indicator, alarm
reset and PLC I/O port. The Control Console will provide the
user with measured radiation levels for each detector, alarm
information, power interruption data, system maintenance messages
and date/time. The Console will also allow the adjustment of
alarm threshold levels, printout of alarm and power interruption
data and various other system configuration functions. There
is an option to connect the plants PLC system for the downloading
of alarm locations.
The system user will have full and complete control over the
systems operating condition. Because of the critical function
of the Off-Gas/Dust Collection system radiation detection system,
it is extremely important that the more information that can
be provided to the User the better. The detectors signal discriminator
settings and signal process algorithms cannot be adjusted but
there will be full adjustment capability of the RC/300 Controllers
permutations and combinations alarm algorithms. In addition,
the resultants (alarms) of the User set permutations and combinations
analyses will be made available via the PLC I/O port. This
information together with selected variables from the Off-Gas/Dust
Collection system, such as, flow rates and mechanical valve
I/O signals, the Rad/Comm PLC flow chart alarm algorithm can
be customized for each plant application.
|
