CTS and H2 Recombiners

Question 1

What is the purpose of the CTS system?

Answer 1

• Limits post-accident containment pressure and temperature to less than design values of 12#
• Removes radioactive elemental iodine from the containment atmosphere in the event of a DBA.

Question 2

What is the purpose of the H2 Recombiner?

Answer 2

• Control the hydrogen generated in the containment after a loss of coolant accident (LOCA)

Question 3

What is the purpose of DIS?

Answer 3

• The DIS eliminates hydrogen in the containment following a LOCA to prevent a detonation by period ignition of h2 mixtures

Question 4

What are the ESF systems in the plant?

Answer 4

• Ctmnt Structure
• ECCS System
• Ice Condenser
• CTS

Question 5

What are the CTS pump starts?

Answer 5

• Load Shed (W/ Phase B)
• Phase B
• Manual

Question 6

What are the CTS pump Trips?

Answer 6

• Load Shed
• Overload/Overcurrent
• Manual

Question 7

What causes a CTS signal?

Answer 7

• 2.8# (2/4)

Question 8

What are the fission product barriers?

Answer 8

• Fuel Clad
• RCS
• Ctmnt building

Question 9

What do you declare if you lose one or potential to lose one fission product barrier?

Answer 9

• Unusual event

Question 10

What do you declare if you lose two fission product barriers and potential to lose a thrid fission product barrier (Fuel Clad or RCS Barrier)?

Answer 10

• General Emergency

Question 11

What do you declare if you lose any TWO of the following:

1. Loss or Potential Loss of Fuel Clad.
2. Loss or Potential Loss of RCS.
3. Loss of Containment Barrier.

Answer 11

• Site Area Emergency

Question 12

What happens on a SAT low-low lvl?

Answer 12

• SAT outlet valves close and eductor suction valves should have closed prior to the SAT Low Low lvl alarm but it sends the signal again

Question 13

What is the CTS flow to upper ctmnt spray header?

Answer 13

• 2000gpm

Question 14

What is the CTS flow to lower ctmnt spray header?

Answer 14

• 1200gpm

Question 15

Which CTS header does RHR feed and how much flow?

Answer 15

• Upper ctmnt spray header only, and 2000gpm

Question 16

What is the intended pH of the recirc sump due to CTS?

Answer 16

• 7-10 pH

- want 8.5 pH to keep iodine in solution

Question 17

What is added to the SAT to help remove radioactive iodine?

Answer 17

• Sodium Hydroxide

Question 18

What do we use in the SAT to minimize moisture?

Answer 18

• Nitrogen overpressure

Question 19

Can the H2 Recombiners be started in modes 1-4?

Answer 19

• Yes, but you have to declare the EDGs inoperable because it will over load the EDGs in the event of an SI with LOOP

Question 20

What powers the H2 recombiners?

Answer 20

• 11/21 B

- 11/21 C

Question 21

Will the H2 recombiners trip on a load shed?

Answer 21

• No, they do not

Question 22

Will the CTS pump auto start on a Containment Spray Signal?

Answer 22

• No

Question 23

Main Steam Isolation comes from with Ctmnt iso phase?

Answer 23

• Phase B (Auto only)

Question 24

What will 2.8# in ctmnt cause?

Answer 24

• Phase B
• Ctmnt Spray Actuation
• Steam Line Iso (auto only)

Question 25

What are the auto actions of a Ctmnt Spray Actuation?

Answer 25

• CTS pump disch valves open
• SAT outlet valves open
• CTS pump seq on after approx. a 4 min time delay (as long as white light is lit)

Question 26

What are the H2 production sources?

Answer 26

• Zirc (Clad) H20 reaction
• Radiolytic decomp of H20
• Corrosion of metals inside containment

Question 27

How is Air drawn into the H2 recombiner units?

Answer 27

• natural convection. We ensure this happens by controlling the power to the units.

Question 28

What is the purpose of the Spray Add educator?

Answer 28

• Draws the NaOH solution from the SAT and mixes it with a portion of the CTS pump discharge flow

Question 29

What must be closed before you can open ICM-305 and 306?

Answer 29

• IMO-310/320 closed

- IMO215/225 closed

Question 30

When do the ESW to CTS Hx outlet valves throttle open and to what flow?

Answer 30

• Throttle open on a CTS Signal and ICM 305/306 open to 2400gpm