this unit is equipped with additional protection methods to avoid dangerous
pressure build-up in the filter.
E-PAK 150 DX/300 DX/500 DX is equipped with either an explosion relief
panel, see Section 4.1.1 Method 1: Explosion relief venting, or an explosion
suppression system, see Section 4.1.2 Method 2: Explosion suppression system.
The suppression system is normally only used if venting is impossible due to
the location of the filter, dangerous material properties or a resulting flame.
4.1.1
Method 1: Explosion relief venting
The harmful effects of an explosion are minimized by venting the pressure
and flame of the explosion through an explosion relief panel. In case of an
explosion, the resulting flame and pressure escape through the explosion relief
panel which is to be directed towards a safe area without any people. This area
is referred to as the 'risk area'.
The risk area is to be clearly marked, for example with a fence, warning lines
and signs, and entry is prohibited when the filter is in operation. The area is to
be free of any flammable or combustible material or other objects which may
be damaged by the flames and explosion pressure.
The general size of the risk area is shown in Figure 6. The following
dimensions apply:
•
A=8 m (26.2 ft)
•
B=2 m (6.6 ft)
•
C=3.5 m (11.5 ft) or ground level, if elevated
•
D=4 m (13.1 ft)
NOTE!
The risk area may extend beyond the values given above. The
final risk area is to be evaluated with regards to affecting factors found in
Standard EN 14491.
4.1.2
Method 2: Explosion suppression system
With an explosion suppression system, the early stage of an explosion is
detected with optical and/or pressure-sensitive devices, and an extinguishing
agent is quickly dispersed into the filter. The suppression of the explosion
is initiated an extremely short time after detection of the explosion (in
milliseconds), and stops the pressure rising and extinguishes (suppresses) the
flames of the explosion.
This ensures that the filter is not stressed to a dangerous level by the explosion.
The key components of the explosion suppression system are the following:
•
An explosion detection device (optical/pressure-sensitive).
•
A computer-operated control unit.
•
Action elements such as pressure cylinders containing an extinguish agent
with an extra fast opening valve.
Detailed information regarding system installation, function, operation and
maintenance can be found in the suppression system manual.
E-PAK 150 DX/300 DX/500 DX
EN
27