Taking on the world

Pulp & Paper, Oct 2004 by Shaw, Monica

SP Newsprint in Dublin, Ga., has used a can-do attitude in lieu of capital alone to take some of the world's top productivity prizes with its No. 2 paper machine

It has been six years since SP Newsprint completed the $25-million rebuild of its No. 2 paper machine, but the improvements have continued-and so have the accolades. Ranked as the most productive newsprint machine in the world for two consecutive years by the Pulp and Paper Products Council, the 100% recycled newsprint machine has achieved this and other awards through vigilant maintenance, employee innovation, and a quest for perfection up and down the paper machine.

The Dublin, Ga., mill also attained these rankings without the assistance of major capital. Since Pulp & Paper visited the mill in 2001 (see P&P, July 2001), only $4 million in capital improvements has been spent in the quest to remain highly productive for the media partners-Cox Enterprises, Knight-Ridder, and Media General-that own SP Newsprint. The partnership consumes about 40% of SP Newsprint's production.

"We feel like we owe it to our owners to provide a long-term supply of newsprint, and because it's a commodity grade, the only way to stay successful is to be a low-cost, quality producer," says Dublin mill manager Jack Carter. "We have to be highly productive and dilute fixed costs without creating higher variable costs. If we're going to stay in business, we can't stay where we are; we have to get better."

SP Newsprint's No. 2 paper machine was installed in 1989. Though the machine may be considered fairly new by North American standards, Carter considers it from its global "vintage" status. This broad outlook is what spurs the Dublin mill toward perfection on the No. 2 paper machine as it seeks to capture and hold recognition in the areas of speed and efficiency.

"Our competition isn't just Tennessee, Georgia, Alabama, and Canada," Carter describes. "It's Sweden, Belgium, Germany, England, and maybe even someday Korea and China. So, if you want to be a player in this area, you can't let bottlenecks go unaddressed. It's a challenge for ourselves and our suppliers in that what works today won't necessarily work tomorrow."

In 2001, SP Newsprint vice president Mark Rawlings told P&P that the Dublin mill would work through all bottlenecks if economically feasible in an effort to "keep trying to push the envelope." This focus has translated into adoption of new technology from suppliers, as well as innovations from mill personnel (see sidebar, p. 36). Pushing the envelope has even resulted in stepping away from supplier recommendations at times.

"Capital is tough to come by, so sometimes this leads to tweaking our design instead of buying something new," Carter explains. "Everything on the No. 2 paper machine has been touched. We don't mind taking risks in order to move forward."

During the past three years, the main areas of work for improving productivity have included new stock screens and former ceramics, as well as efforts to reduce vibration throughout the No. 2 paper machine. In addition, a focus on reducing center roll draw from the press into the dryers has received much attention.

Screening stock for contaminants

While most of the debottlenecking improvements made on the No. 2 paper machine since 2001 were not major capital projects, the $3.2-million installation of Metso thick stock screens marked an exception, as did installation of a new flat box and former ceramics. Despite equipment in the deink plant such as coarse screening, slotted screening, cleaning, and washing, contamination was still proceeding to the paper machine, so thick stock screens were needed to help reduce sheet breaks. The screens also allowed removal of the breaker stack, which was historically used as a "sticky catcher" but had been an efficiency drain. In addition, the mill had no way to screen broke on the No. 2 machine.

To correct the problems, the mill installed three stages of stock screens prior to stock entering the headbox. Each stage features 0.005-in. and 0.006-in. slotted screens, which helps compensate for the increasingly poor quality of incoming fiber.

"We are sorting our ONP more than we have historically, because SC or LWC grades used in inserts can really bog down our deink process, not to mention create problems with larger contaminants," says Carter. "We try to buy the best to begin with, and our internal divisions help by keeping track of which are the dirty and which are the clean streams."

Stable drying supports higher speeds

A major focus area on the No. 2 paper machine in the last year and a half has been the dryer section. As the Dublin mill tried bumping the speed to 5,700 fpm in 2003, mechanical vibration issues occurred throughout the machine, especially in the dryer section.

The mill backed the speed down by 50 fpm and began tackling the vibration issues through a variety of means, both during shutdowns and on the run. Modifications were both home grown and developed with help from suppliers, and the results have been excellent.