Right material selections
For black liquor with high solids content, ball and segment valves are preferred. For control services, the primary recommendation is the segment valve as well as the ball valve. For lower solids content, a butterfly valve is recommended. Butterfly valves are also preferred in large pipe size steam applications. When solids content rises above 75%, Metso recommends using 4A duplex as the valve material.
Raw white liquor and white liquor dregs require the use of ball valves with rugged metal seats and a scraping and locking mechanism, like the Metso ball valve. Lime mud is a very erosive flow medium. For such applications, our ceramic ball valve offers the best resistance to erosion.
Long life time and reliable operation
- Ball valves do not interrupt the flow as much as butterfly valves; therefore, they are preferred for use in viscous black liquor applications with high solids content
- For control services, more accurate flow control can be obtained by selecting a segment valve
- Butterfly valves are a cost-efficient way to handle low solids content, less viscous black liquor and large pipe size steam applications
- Due to the erosiveness of black liquor in high solids contents, normal stainless steel CF8M is usually not sufficient; with 4A duplex material, the valve can prevent corrosion and erosion
- Due to the erosiveness of lime mud, normal stainless steel CF8M is usually not sufficient; with ceramic material, the valve can prevent corrosion and erosion
Black liquor evaporation and recaustizing
Learn more about how Metso valves work in black liquor evaporation and the recausticizing process.