GR- Gaseous Radwaste Flashcards
[GR] purpose?
- Collects and processes high/potentially radioactive waste gases (Primarily Hydrogen & Nitrogen) generated in plant in an oxygen free system to permit decay of short-lived isotopes.
- Keeps exposure of onsite and offsite personnel within acceptable limits
[GR] Components?
gas surge header,
waste gas surge tank,
two waste gas compressors,
three waste gas decay tanks and associated piping
[GR] Flowpath
Waste Gas Surge Header
Waste Gas Surge Tank
Filter
Compressor - (2 parallel/redundant)
Compressor Discharge Header
Waste Gas Decay Tanks
AOV Isolation Values (2)
Gaseous Discharge Filter
Flow Element,
RU- 12
Flow Control Valve
RW Exhaust
plant vent (w/ additional radiation monitors)
RU - 1
[GR]
RW CR [GR] instrumentation power?
NN
[GR]
Waste Gas Compressors power? Location?
NH
140” RW building
[GR]
[GA - N2] interaction with [GR]?
Nitrogen for the initial system purge
- subsequent purges to allow for maintenance
- Auto Purge - O2 Analyzer hi alarm in surge header
[GR]
What causes gas surge header isolation valves to auto close?
Where does the relief valve on this header discharge to?
CIAS
RW Exhaust
[GR]
Gas Surge header MOV isolation valve power?
PH
[GR]
Gas surge header solenoid operated isolation valve power?
PK
[GR]
Gas Surge Tank purpose?
Absorbs fluctuations in system gas volume to minimize compressor operating time
[GR]
Design temperature of Gas Surge Tank plastic liner?
200 F
[GR]
Gas Surge Tank location?
RW 140’
[GR]
Gaseous Radwaste compressor purpose?
- Pump LP gas from surge tank to decay tanks.
-Auto controlling surge tank pressure
[GR]
In auto, which compressor will start if there is a high surge tank pressure and the mode selector switch is in:
A-lead, B-STNBY
“A” Compressor
[GR]
What starts both compressors in auto ?
Hi-Hi surge tank pressure
[GR] Decay Tanks Purpose?
-holding area for waste gas to undergo radioactive day prior to atmospheric discharge.
[GR]
What automatically causes Decay Tank Discharge Header isolation valves (34A/34B) to close? (4)
What else closes?
Is it auto or manually reopened?
1- Low D/P of [HR] exhaust fan A & B
2 - High waste gas discharge flow
3 - High Rad level
4 - High Pressure - rad monitor supply line
Solenoid AOV flow valve FV-33 causing it to close.
Manually