A Case Study in Replacing Chemical Scale Inhibitor
Abitibi Consolidated - Pulp & Paper Mill
Location: Ontario, Canada
Abitibi-Consolidated (Thorold, Ontario) produces 1,400 metric tonnes of newsprint daily in its FDI 1 & 2 mills. The mill uses recycled newsprint and office waste paper in the company’s de-inking plant. The process involves removing the contaminants in a semi-closed loop system. The white water used in the de-inking process contains large amounts of salts (carbonates of calcium silica and magnesium.)
Over the past 15 years of operation, calcium carbonate and
calcium silicate scale has accumulated in the piping system, disk thickeners, floatation cells and pressure screens. To deal with the scale problem the mill would have to spend approximately $150,000 annually on chemical scale inhibitor to reduce scale build-up in the process equipment. In addition, Abitibi would need to bring in high-pressure cleaners during their shutdowns to hydro-blast the equipment to remove the scale build-up.
Another major cost and maintenance problem was the scale build-up on the sector bags of the disk-thickeners. The FDI 1 mill has 488 sector bags on the 3-disk thickeners. The bags were deteriorating rapidly because of the scale build-up and would need to be replaced every 12-months at costs of approximately $120,000 annually.
GII Scale Control provided Abitibi Consolidated with a no-obligation trial, with the goal of eliminating the use the expensive chemical scale inhibitor. We installed the systems throughout the mill on the white water lines feeding the process equipment. The systems were installed without any shutdown or interruption to the mill's production schedule.
Abitibi Consolidated (now owned and operated by Resolute Forest Products) has since purchased the systems for the FDI 1 mill and has also purchased and installed GII Group Scale Control systems in the FDI 2 mill for complete scale removal and prevention. Further savings were also delivered when the subsequent sector bag change provided a 66% reduction in costs.
APPROXIMATE ANNUAL SAVINGS:
$250,000 - $300,000 in annual savings