Buhler GAS 222.30 Ex2, Installation And Operation Instructions Manual

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GAS 222.30 Ex2
6.2 Backwashing the Intake Filter (within the process stream)
DANGER Adiabatic compression during gas blowback (explosion hazard)!
Adiabatic compression may cause high gas temperatures and must be checked by the
user.
Gas blowback may result in high gas temperatures due to adiabatic compression. This
can cause flammable gases to ignite spontaneously.
a) Blowback of explosive atmosphere / gases is prohibited.
b) Flammable atmosphere / gases (non-explosive) may only be blown back with nitro-
gen (inert gas).
Be sure to use filtered air with a minimum rating of PNEUROP / ISO Class 4 for blowback:
Class Particles / m
3
Particle size:
(1 to 5) µm
Pressure dew point
[°C]
Residual oil content
[mg / m
3
]
4 to 1000
(no particles ≥ 15 µm)
≤ 3 ≤ 5
6.2.1 Manual Blowback (Without Blowback Control)
The shut-off valve in the air supply (inert gas supply) to the pressure vessel must be open. The optional pressure gauge on the
pressure vessel shows the current operating pressure.
– To blowback, first close the shut-off valve in the gas probe (handle below the probe/weather hood).
– Then
abruptly
open the ball valve inside the connecting line from the pressure vessel to the probe until the display on the
pressure gauge has dropped to the lowest reading.
– After blowback, close the ball valve and open the shut-off valve in the probe.
6.2.2 Automatic Blowback (External Blowback Control)
For automatic blowback, the shut-off valve in the probe with must have a pneumatic control (optional). The control unit for the
system is designed for sequential valve control, i.e.:
1. Close the shut-off valve in the probe using the pneumatic control.
2. Open the solenoid valve between the pressure vessel and probe for approx. 10 seconds.
3. Open the shut-off valve in the probe.
Blowback can also be set as a closed process at intervals ranging from several minutes to hours or even days based on require-
ments.
15 Bühler Technologies GmbH BE460064 ◦ 08/2019