Reference Manual

10B −12
— Q = 500 gpm
D Typical valve selection:
— Kamyr has specified a V150 Vee-Ball
valve, NPS 2 – NPS 3 size, with stainless
steel body and ball, Nitronic 50 shaft, PEEK
bearings, and an HD metal seal. Typically, a
fail closed actuator is used.
Valve: LV-17 No. 2 Flash tank level
Black liquor level in the No. 2 flash tank is
controlled by LV-17, located between the No. 2
flash tank outlet and the evaporators.
D Typical process conditions:
— Fluid: Black liquor
— T = 220_F
— P = 60 psig
— dP = 10 – 20 psid
— Q = 1000 – 2000 gpm
D Typical valve selection:
— NPS 8 to NPS 10 butterfly valve that
Kamyr has specified as a stainless steel
HPBV with stainless steel disc, alloy 6
bearings, 17-4 shaft, and a NOVEX metal
seal.
Valve: LV-16 No. 1 Flash tank level
Black liquor level in the No. 1 flash tank is
controlled by LV-16 located at the outlet of the
tank. This valve flows into the No. 2 flash tank.
D Typical process conditions:
— Fluid: Foamy black liquor
— T = 260_F
— P = 20 – 50 psig
— dP = 2 – 12 psid
— Q = 500 – 1500 gpm
D Typical valve selection:
— This valve is specified by Kamyr as a
HPBV with a stainless steel body and disc
and a NOVEX metal seal. alloy 6 bushings
and a 17-4 shaft are recommended. This
valve is in the NPS 8 to NPS 14 size range.
Valve: LV-81 Clean condensate flash
tank level
D Typical process conditions:
— Fluid: Clean condensate
— T = 312_F
— P = 90 psig
— dP = 90 psi maximum
D Typical valve selection:
— This valve has been specified by Kamyr
to be a NPS 2 to NPS 3 V150 valve with
stainless steel body and trim, Nitronic 50
shaft, HD metal seal, PEEK bearings, and a
fail-close actuator.
Valve: LV-91 Contaminated condensate flash tank
level
D Typical process conditions:
— Fluid: Condensate
— T = 212_F
— P = 11 psig
— dP = 10 psi
D Typical valve selection:
— This valve has been specified by Kamyr
to be a NPS 2 to NPS 3 V150 valve with
stainless steel body and trim, Nitronic 50
shaft, HD metal seal, PEEK bearings, and a
fail-close actuator.
Valve: KV-24 Sand separator valve
This is also called the “pocket valve”. This is a full
bore ball valve with one of the normally open ends
of the ball sealed. It is used to collect sand at the
bottom of the sand separator. Occasionally, the
valve rotates 180_ to dump the collected sand.
D Typical valve selection:
— Full bore valves that can rotate 145
degrees are chosen. It is typically NPS 6 to
NPS 8, and cycles every five to ten minutes.
El-O-Matict actuators with 180 degree
rotation with an adjustment are used
commonly. Due to high cycle life, this valve
assembly needs to be inspected on a regular
basis.
Heating Stage
From the impregnation zone, the chip column
continues to move down until the upper cooking
zone is reached. Chips and liquor are pre-heated
to within 20_F of the actual cooking temperature
while the lower cooking zone controls the final
cooking temperature. This is accomplished by
withdrawing liquor from the digester through a
screen plate, circulating it through an indirect
heater and returning the heated liquor down
through a central distribution chamber. Then, it is
discharged at a point opposite and slightly above
the screen plates. This allows the chips to receive
uniform heating as the liquor enters at the center