Implementation of a metering size press on PM2 at the Georgia Pulp and Paper Macon Mill

Abstract

The GPP-Macon Mill is in need of a strategic project to bring the mill into a better cost position. Currently the mill is limited by a machine bottleneck after the size press. A metering size press (MSP) can be installed to replace the current puddle size press to eliminate the production bottleneck. With the installation of a metering size press, starch can be added to the sheet at upwards of a 12 percent solids content. This higher solids content decreases the amount of drying needed after the size press. In addition to achieving a higher starch solids with the MSP, the necessary starch pickup can also be reduced to around 3.5 percent since less starch sizing penetrates the sheet with an MSP. The new metering size press can increase availability of the machine by causing fewer breaks due to a dryer sheet leaving the size press while maintaining the current sheet properties. However, availability may not be gained with an increase in machine speed. In case studies it has been shown that a machine speed up can be achieved with a metering size press.

WinGEMS analysis shows that replacement of the current puddle size press with a metering size press, decrease of starch pickup by 1.5% and a 5% speed increase on PM2 can net a cost savings of $9MM/year. These savings are due to less after size press drying required with the increased solids starch solution and starch cost savings from the decrease in pickup. With surface sizing starch being a major cost to the mill, the project can yield high returns.

Upon consideration of the full project analysis, it is recommended that GPP move forward with the option of installing a metering size press on PM2, increasing machine speed by 5%, and decreasing the starch pickup to 3.5%. This project yields a high IRR of 40.9% with low risk.