Liquid Radwaste System

Question 0

What liquid Radwaste is not normally processed by the LRS system?

Answer 0

Borated and tritium RCS quality water are normally treated by BAC.

Question 1

When do we send LRS distillate to the spent fuel pool?

Answer 1

Since the water is clean, we only send it there when we are making up for evaporative losses so we don’t dilute the boric acid concentration.

Question 2

What is aux steam used for in the LRS system?

Answer 2

AS provides steam to the LRS evaporator

Question 3

What provides cooling to the LRS evaporator surface condenser, distillate cooler, and vent cooler?

Answer 3

NC

Question 4

What are the subsystems of the LRS system?

Answer 4

Total Dissolved Solids 
evaporator
Concentrate monitor
Recycle monitor
Chemical drain

Question 5

What will cause the LRS holdup pumps to trip?

Answer 5

if any TDS holdup tank falls to 500 gallons the pumps will trip and the evaporator feed valve will close.
A LOW LOW LEVEL IN ANY TANK TRIPS ALL 3 PUMPS

Question 6

Where do LRS holdup tanks overflow to?

Answer 6

each other before overflowing to the radwaste building sump

Question 7

Why is there a caustic tank and a caustic batch tank?

Answer 7

to prevent inadvertent drainage of the storage tank contents to the LRS holdup tank

Question 8

Where does the caustic tank overflow go?

Answer 8

neutralizing bed south side of the RW building

Question 9

How is the caustic tank filled?

Answer 9

from a truck fill connection on the outside wall of the RW building. the fill valve will automatically close when level signal indicates 40”.

Question 10

Where can anti-foaming agent be added to in the LRS system?

Answer 10

the TDS tanks or the LRS Evaporator

Question 11

How is the anti-foam tank filled?

Answer 11

via a hand pump along with a hose

Question 12

What will trip the anti-foam pump?

Answer 12

low level in the tank at 13”

Question 13

What does the vapor body of the LRS evaporator do?

Answer 13

serves as the primary separation chamber to release vapor from boiling liquid. Houses the moisture separator pads that prevent carry over.

Question 14

Where are the non-condensable gases from the surface condenser vented?

Answer 14

radwaste building ventilation exhaust via the vent cooler

Question 15

How does the gas stripper improve distillate quality?

Answer 15

by removing volatile impurities from the distillate using the vapor produced in the reboiler. the distillate collects in the bottom of the gas stripper

Question 16

Where does the distillate go after it leaves the distillate cooler?

Answer 16

to the charcoal filter and then to the ion exchangers.

Question 17

How many distillate pumps are normally running?

Answer 17

one, the other is in standby.

Question 18

What does the main recycle pump do?

Answer 18

take a suction on the liquid portion of the vapor body and discharge to the heating element

Question 19

Where do the evaporator concentrate pumps send the concentrated liquid radwaste?

Answer 19

to the concentrate monitor tanks and the density transmitter

Question 20

What is the source of heat for the heating element in the vapor body?

Answer 20

Aux steam

Question 21

Where does the AS condensate from the heating element get directed to?

Answer 21

pumped to the AS condensate receiver tank using the steam condensate pump

Question 22

What type of resin is used in the ion exchangers?

Answer 22

mixed bed resin

Question 23

How are the ion exchangers normally operated?

Answer 23

in series but they may be operated in parallel if necessary

Question 24

What are the recycle monitor tanks used for?

Answer 24

store processed liquid radwaste from the ion exchangers.

Question 25

Where are the recycle monitor tanks vented to?

Answer 25

atmosphere

Question 26

Where can the recycle monitor pump send water to?

Answer 26

RMWT, CST, Spent resin tanks, spent fuel pool

If it’s not acceptable for reuse, then it can also go back to the LRS holdup tanks for re-processing

Question 27

What will trip the recycle monitor pump?

Answer 27

hi hi discharge pressure
lo lo level
or electrical protection

Question 28

Where are the concentrate monitor tanks?

Answer 28

inside the radwaste building 100’ level

Question 29

What happens if the cross tie valve is open and concentrate monitor tank A gets a low low level?

Answer 29

Both pumps will trip off. if the valve is closed, only the associated pump will trip off.

Question 30

What goes to the chemical drain system?

Answer 30

detergent and chemical wastes from the chem lab sinks and the decon laundry facility (unit 1)

Question 31

Where do the chemical drain tanks vent to?

Answer 31

the aux building ventilation exhaust header

Question 32

What will trip the chem drain pumps?

Answer 32

loss of power to associated pressure switches
low level its associated tank or if the cross tie valve is open, low level in either tank
high discharge pressure will stop the pump

Question 33

What happens if the LRS evaporator is down?

Answer 33

high TDS wastes can be sent directly to solidification and low TDS can be sent through the IX

Question 34

What happens to the LRS if NC is lost?

Answer 34

the evaporator secures to prevent resin damage

Question 35

What happens to the LRS if RX makeup water is lost?

Answer 35

all pumps that are operating that use rx makeup water as a source for its seal water must be shutdown