Five years after the introduction of a transformative barge unloading system, our Hawesville Mill continues to embark on projects that help increase reliability and performance in producing pulp and paper. These continuous improvement projects are saving time, reducing costs, increasing efficiency and lowering our environmental impact.
Conveyor Belt Reduces Traffic, Pollution
In 2014, we worked with Ingram Barge Company to develop an innovative barge unloading system that uses a mile-long conveyor to deliver wood chips from the banks of the Ohio River to the mill. The system eliminates the need for truck transportation, which has drastically reduced traffic congestion and pollution. In its five years of operation, the conveyor has eliminated more than 270,000 truck trips from local roads and saved about 550,000 gallons of fuel.
“The Hawesville Mill chip conveyor is an agile and unique solution that’s paying dividends for us,” says Bill Edwards, vice president of manufacturing for communication papers. “It’s just one example of a number of continuous improvement projects at the mill — and across our entire mill system — that are allowing us to take another step forward in productivity and reliability.”
Data Analysis Increases Efficiency
In 21st-century manufacturing, data is king. That’s why one of our continuous improvement projects is a plant analysis and visualization tool called PARCview to monitor up-to-the-minute manufacturing data across our network of 13 pulp and paper mills.
In the same spirit, the Hawesville Mill is testing a state-of-the-art wood chip moisture analyzer to provide operators real-time data that keeps the mill’s chip digesters running smoothly.
Digesters are similar to large pressure cookers, where wood chips mix with chemicals and steam. Over a period of several hours, the digester separates the lignin from the wood fibers we use to make pulp. Strong process control is essential, particularly at this stage.
“Chip moisture can vary based on any number of conditions,” says Hawesville Mill Manager Grant Forrest. “Differences in wood density due to moisture can cause variability in our digester’s yield.”
Historically, the mill tested chip moisture weekly. Because that data wasn’t timely, it couldn’t be used to control digester operations. “Real-time data is key,” Forrest says. “With the chip moisture analyzer, we will be able to better manage our chip blends and liquor flow to optimize the digester and reduce variation.”
Better Design Reduces Downtime
Wood-chip flow through the wood digester is another area that is ripe for improvement. Over the past three years, the mill has lost an average of 3,500 air-dried metric tons of production due to chips flowing unevenly through the bin, creating plugs. So the team contacted the bin manufacturer to discuss the issue.
“In working with the equipment manufacturer, we discovered they made a design change after installing our bin that improved chip bin flow,” Forrest says. “We incorporated the design change and reoriented the bin during our fall 2018 outage, and the results have been much improved.” (Our Kamloops Mill saw similar improvements after updating its chip bin during one of its continuous improvement projects.)
“No matter how large or small, teams across our mill system are always looking for opportunities to improve efficiency, and I’m proud of the production gains we continue to make at each of our paper mills,” Edwards says.