Reference Manual

10B −16
Valve: KV-16A-D Digester extraction
switching valves
These valves provide screened liquor extraction
from the upper wash zone of the digester. This is
located near the middle of the digester vessel. The
extracted liquor is then sent to flash tank No. 1.
The KV tagged valves are required to fully stroke
approximately every 90 seconds. This causes a
flow reversal through the extraction screens
preventing the screens from plugging with chips
and fiber.
D Typical process conditions:
— Fluid: Black liquor
— T = 325_F
— P = 10 psig
— dP = 150 psi
— Q = 1500 gpm
D Typical valve selection:
— NPS 6 to NPS 8 size range. The DSV
valve is suitable for this application. This is a
modified 8510 body with a strengthened
shaft and no seal. Used in conjunction with
the 1061 actuator with a quad seal option,
this assembly is capable of a relatively long
life in this service.
Valve: TV-9H Modified cooking
circulation temperature valve
This valve controls steam to the Modified cooking
heater which, in turn, controls the temperature of
liquor going to the upper wash zone.
D Typical process conditions:
— Fluid: Steam
— T = 379_F
— P = 165 psig
— dP = 80 psi
D Typical valve selection:
— This is a throttling valve, typically NPS 4
to NPS 6, for which Kamyr has specified
V300 valves with stainless steel bodies and
stainless steel trim. Nitronic 50 shafts, PEEK
bearings, and HD metal seals are also called
for.
Valve: HV-20 Washer heater circulation
flow
This valve controls the flow of wash liquor from the
bottom of the digester to the wash circulation
heater of the main digester.
D Typical process conditions:
— Fluid: Black liquor
— T = 255_F
— P = 250 psig
— dP = 20 psi – 60 psi
D Typical valve selection:
— This is typically not a scaling application.
A V300 valve or a CV500 will be suitable.
Valve: FV-14 Inner counterwash flow
This valve controls the flow of washer filtrate to
the pulp washing section of the digester vessel
and is typically a NPS 4 valve.
D Typical process conditions:
— Fluid: Washer filtrate
— T = 170_F
— P = 235 – 350 psig
— dP = 5 – 130 psid
— Q = 100 – 1000 gpm
D Typical valve selection:
— Kamyr has specified a V300 valve with
stainless steel body and ball. The valve
should be offered with a Nitronic 50 shaft,
PEEK bearings, and an HD metal seal. A
piston actuator is normally specified.
Valve: TV-20 Wash circulation
temperature control
This valve controls the flow of low pressure steam
to the wash circulation heater for the digester.
D Typical process conditions:
— Fluid: Steam
— T = 379_F
— P = 165 psig
— dP = 55 psi
D Typical valve selection:
— This is a throttling valve, typically NPS 6
to NPS 8, for which Kamyr has specified
V300 valves with stainless steel bodies and
stainless steel trim. Nitronic 50 shafts, PEEK
bearings, and HD metal seals are also called
for.
Valve: KV-20A-D Wash extraction
switching valves
These valves extract wash water from screens
located near the bottom of the digester vessel.
The extracted wash water is then sent to the wash
heater.