Term
OG
Describe the function of the preheater. |
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Definition
-Adds an addition 50F of superheat to offgas before getting to recombiner.
-Prevents condensation in the recombiner and wetting the catalyst.
-Uses main steam from the SJAE supply line at 260#. |
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Term
OG
Describe the state of the gas at the preheater. |
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Definition
-Enters at low pressure (alarm at 19.5#).
-Leaves at 370F (alarm at 270F). |
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Term
OG
Describe where preheater condensate goes. |
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Definition
-Condensate produced in the preheaters shell side is collected in the hotwell and discharged to the condensate flash tank.
-Has a high level alarm at 3/4. |
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Term
OG
Describe dilution steam. |
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Definition
-Yields H2 at <4% by volume.
-Keeps recombiner <850F.
-Main Steam that taps off of the A & B steam lines. |
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Term
OG
Describe the minimum operating temperature of the catalyst. |
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Definition
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Term
OG
Describe the electric heaters for the recombiners. |
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Definition
-Mounted at bottom of recombiner right after the preheater.
-Cycle at wall temp of 300-350F.
-Keeps catalyst bed >212F. |
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Term
OG
Describe the recombiner effluent. |
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Definition
-Wet high temp (500F) leaves recombiner and enters desuperheating condenser.
-Cooled by condensate water and steam is collected in hotwell.
-Dry cool off gas (115F) goes to 42" delay line. |
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Term
OG
Describe the condensate flash tank. |
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Definition
-Seperates high temp from low temp influents to tank by allowing high temp influents to flash to steam at low press (8psia).
-Vents flashed vapor to main condenser.
-Low temp influents drain to Drain Cooler. |
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Term
OG
Describe the Drain Cooler. |
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Definition
-Reduces condensate flash tank drain temps before returning them to main condenser.
-Cooled by main condensate. |
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Term
OG
Describe H2 & O2 analyzer. |
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Definition
-Draws suction from upstream of AO-7557A/B on discharge of desuper condenser.
-Sampling is returned to main condenser. |
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Term
OG
Describe the H2 & O2 analyzer alarm and trips. |
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Definition
-Any 1 of 3 analyzers can cause alarm.
-Alams at >2%.
-2 of 3 >4% and AO-7557A/B open and 10 seconds cause off gas compressor to trip. |
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Term
OG
Describe what instrument air does. |
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Definition
-Provides enough O2 for recombination.
-Purge recombinber after shutdown. |
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Term
OG
Describe pretreatment rad monitoring. |
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Definition
-Gives alarm and terminates off gas flow for high rad.
-2 of 2 logic.
-2 high, 2 low, 1 high 1 low, trips.
-Starts 30 minute timer and after timer off gas flow is terminated by shutting (AO-7557A/B) Desup condenser outlet and (AO-1085A/B) intercondenser outlet.
-These valves fail closed on loss of air. |
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Term
OG
Describe the desuperheating condeser high temp alarm and what happens. |
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Definition
-170F.
-Shuts condenser outlet valve (AO-7557A/B). |
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Term
OG
Describe air ejector low steam pressure trip. |
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Definition
| -If less than 110# for 5 seconds at 2nd stage nozzle will shut inter condenser outlet (AO-1085A/B) and desuper condenser outlet (AO-7557A/B). |
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