By Graeme Rodden, Executive Editor, Pulp & Paper International magazine
Built in 1949, Green Bay Pulp & Paper was the first mill to commercially produce neutral sulfite semi-chemical pulp (NSSC). At startup, it produced corrugating medium from 100% virgin fiber (hardwood). It began using post-consumer waste (OCC) in 1957, setting the stage to using a 100% OCC furnish in 1991. In 1962, Green Bay Pulp & Paper merged with Green Bay Box (see sidebar) to become Green Bay Packaging.
The mill's first and only machine had its first wet end rebuild in 1982. Most of the original machine was Black Clawson. In 1989, the entire machine was rebuilt by Beloit. The rebuild included a primary headbox, fourdrinier table, redesigned first press, extended nip second press, high pressure dryers, AC drives, rewinder and a distributed control system (DCS). At this point the mill increased its recycled content to 50%.
A couple years later, in 1991, Phase II of the rebuild took place. This included the installation of a BelBond top former and secondary headbox. It was then that the mill closed its pulp mill and recovery plant, moving to a 100% recycled furnish. It also converted from producing medium to linerboard.
However, the Green Bay Packaging Mill Division has since returned to producing medium, which accounts for about half of its 232,000 tons/yr (660 tons/day).
Quality at the fore
Although quality was not a problem, the mill is always striving for continued improvement. "Over time, things were getting older and obsolete," Vandenberg says. "We needed to increase our productivity, but to do so we needed to continue to improve quality."
"There were a lot of issues," adds electronics and instrumentation superintendent Richland Allen. "There was a lack of `communication' between the systems. We had to reset the linear steppers too often. We would lose our mapping and get choppy profiles. We needed a unified source/system."
Operators were spending too much time maintaining the scanner. Also, calibrating the individual actuators was a problem connected with the communication issue.
800xA was the answer
Vandenberg says the mill started working on the project in 2008-2009 and it was approved in early 2010. The mill turned to ABB for the solution. The scope of supply included an 800xA Version 5 QCS with network platform, automatic grade change and coordinated dryer control as well as new 800xA hardware for the ABB 4-in. linear steppers.
With a Harmony connect, the system was interfaced to the existing MD actuators for speed, weight and moisture controls. Additionally, the 800xA system was interfaced to a new ABB Air Water Profiler for CD moisture control and existing CD weight actuators for CD weight control.
The new system was a standalone project for the mill other than a shower upgrade. The equipment was installed during the course of normal shutdown on October 14, 2010. The mill was able to install some pieces such as the Air Water Profiler during an earlier shutdown so maintenance and operations crews were able to complete the work in one day instead of the two scheduled.
Other work connected to the project such as the water supply system, piping, consoles, installing the hardware and software could be done when the mill was running. "The only thing left for the crews to do was take out the old scanner, install the new one and do the final tie-ins," explains Allen. "They were able to do it all in about 12 hours."
To be continued ... Read Part II here .
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