Brochure

A batch digester is essentially a large pressure cooker. As steam is applied to the mass of chips and liquor, a quantity of resinous vapors are
distilled off. These vapors, along with entrained air in the chips and a small quantity of non-condensed steam, can collect at the top of the
digester. These accumulated additional gases can be sufficient to indicate false high pressures relative to the steam saturation temperature
inside the digester, thereby causing the wood chips to be undercooked.
If a gas relief valve is necessary, then gases, cooking liquors, cellulosic fibers and chips can severely erode and corrode the gas relief valve.
Batch Digester Gas Relief
Product Solutions
14 | Fisher
®
Pulp and Paper Solutions
Cooking
n EROSION CONTROL Specially designed valve body and trim combats the process of erosion.
n WEAR RESISTANCE Solid metal seat ring and valve plug for erosion resistance and long service life.
n RUGGED CONSTRUCTION Sealed metal bearings help prevent particle buildup and valve shaft seizure.
n TIGHT SHUTOFF Self-centering seat ring and rugged plug for tight shutoff and reduced internal wear.
n EASY INSTALLATION Centering holes and line ange bolts reduces valve centering issues for easy installation.
n POSITIONER FEEDBACK Linkage-less and non-contact feedback improves reliability in high vibration.
Fisher V500 control valve, 1061 actuator, and FIELDVUE DVC6200
Cooking