The problem
A major pulp mill in Louisiana was experiencing serious operating problems with its Cl₂/ClO₂ scrubbers. Gas flows had increased to the scrubbers, impairing performance. All scrubbers in the system were near flooding, and removal efficiency had fallen to only 45% — far below the mill's requirements for effective white liquor recovery. Recovered white liquor has direct cash value: it reduces lime makeup requirements and improves overall pulping yield.
A tiger team was formed to address the problem. The team determined that the scrubbers were in good condition but that the installed packing — 2″ Intalox saddles — was not meeting removal efficiency requirements and needed to be replaced.
Through years of continuous operation, the system averaging 98% removal efficiency and more than $400,000 per year in white liquor savings — compared to 45% efficiency with Intalox saddles.
Why LANPAC was selected
Several companies were contacted to propose solutions. They were told that the gas system would be monitored carefully and that removal efficiency of the packing would have to be guaranteed by the successful bidder. Lantec was the only company to offer a performance guarantee for scrubber efficiency, and was subsequently selected for the project.
Meeting the requirements
Through years of continuous operation, the system utilizing 3.5″ LANPAC averaged 98% removal efficiency — more than double the 45% achieved with Intalox saddles. Plugging problems were reduced significantly, gas flow increased more than 40% above the previous operating rate, and savings in white liquor costs reached more than $400,000 per year.
The mill's success with Lantec resulted in a conversion of all of their tower packings to 3.5″ LANPAC.