At Rayonier’ Jesup, Ga., mill, a five-year plan for automation and IT boosts fluff pulp and chemical cellulose quality, while reducing costs

Rayonier Uses Control/Information Technology to Improve Pulp Quality

Over the years, the company has continuously modernized the Jesup mill. As part of these efforts, Rayonier embarked upon an aggressive five-year plan in 1996 to further upgrade its pulp making operations, which include three fiber lines producing fluff pulp and chemical cellulose grades. The plan included both process control and information technology (IT) projects affecting virtually the entire mill.

Figure 1: To achieve its automation and information technology objectives, Rayonier devised a pyramid approach where initiatives in each area would simultaneously start at the top and bottom and meet in the middle via open systems technology and robust networks.

In the area of process control, Rayonier has automated all 28 digesters, a task that was especially crucial for the technically demanding production of chemical cellulose. In addition, all three fiber lines are now automated, and distributed control system (DCS) data from the digester and fiber line control systems are accessible from a standard user interface in a new, state-of-the-art control room.

In addition, new business and information systems are further leveraging the investment in process control by allowing information to flow throughout the pulping operations and business and research systems. These projects include an enterprise resource planning (ERP) system, as well as data historian and transportation software.

According to senior vice president of specialty pulp Bill Kindler, these projects were part of Rayonier's efforts to continually improve quality and performance and reduce costs.

“ produce highly technical pulps for highly technical uses,” states Kindler. “ is a specialty business, and customers make decisions based on product performance, not just price. We need all the tools available to provide them the best product possible.”

Although the digester automation resulted in the loss of operator jobs, Kindler notes that the systems have been accepted. “ worked closely with the union to overcome their understandable concerns,” Kindler says. Pulp mill operator and local PACE International Union vice president Bill Mercer confirms. He says, “ was difficult to accept all the changes, but we recognized the need to remain competitive, so we worked with the company to get the best result and minimize the impact on those we represent.”

All 28 batch digesters and three fiber lines are now automated at Rayonier’s Jesup, Ga., mill, and DCS data from these systems are accessible in a new, state-of-the-art control room.

SPECIALTY PRODUCTS DRIVE AUTOMATION. Products from Rayonier's Jesup mill are divided into two primary categories: chemical cellulose (dissolving pulp) and absorbent fluff pulps. The mill's 550,000-tpy capacity is typically split between the two categories, but can vary with market conditions.

Within the chemical cellulose category, the mill produces 3 primary pulp types: hardwood acetate pulps for products such as cigarette filters, high tenacity viscose pulps that are used for both tire cord and food applications, and a specialty paper type pulp that is used for high porosity filter applications.

Rayonier has a leading (number one or number two) global share position in each of its high-end chemical cellulose and specialty fiber market segments. It is ranked fourth in volume sold into the more commodity-driven fluff pulp market. The Jesup mill has nearly 400 customers and over two-thirds are international.

Demand for fluff pulps, used for personal hygiene products, and high porosity filter pulps continues to demonstrate steady growth. Also, the company has launched a major new product deployment effort that capitalizes on its mill technology and research expertise in cellulose chemistry. Rayonier is starting to see results from these initiatives -- particularly in the specialty fibers and pre-formed hygiene core areas.

Rayonier began examining automation as a way to secure its standing in specialty pulp markets in the mid-1990s. With two of three pulping facilities installed in the 1950s, it became obvious that modernization at the Jesup mill was needed to insure its technical leadership role with customers and to improve overall financial performance. Also, concerns for upcoming environmental requirements, as well as concerns for safety, were pressing factors.

Assuring a quality fiber supply. Modernization at the mill began in the woodyard with a $40 million investment in 1995. Old roundwood chipping operations were replaced with a modern chip receiving and chip, overs, and fines screening operation that incorporated an Allen-Bradley PLC. In addition, a new woodyard procurement strategy was also initiated, which involves Rayonier purchasing all its wood on the open market -- even that from its own timberlands -- through its Southeast wood procurement group.

According to Royce Daniel, company vice president and mill general manager, starting at the back end of the mill was crucial to improving reliability and reducing variability in the specialty pulp making process. The wood procurement strategy has allowed the mill to expand its 100 mile radius for purchasing wood to a 300 mile radius, while containing chip costs and improving quality and reliability of supply. Also, new software from Baywood Technologies has helped Rayonier closely track wood inventory and eliminate species contamination using smart card technology that prohibits drivers from unloading chips in the wrong area.

“ deal with about 30% in hardwood and the remainder in three varieties of pine chips -- low bark, sawmill residual, and generic pine,” describes Daniel. “ different product lines that use softwood or hardwood chips causes us to perform grade changes all the way at the back end of the mill. Our hardwood acetate grades are intolerant of any pine contamination -- zero.”

Justifying automation/IT projects. Rayonier began examining further automation projects in order to improve pulp quality and productivity in 1995. A five-year strategic plan was developed -- an initiative led by manager of controls and process information Horace Carter -- and presented to management in 1996. This plan not only included automating the pulp making process, but also featured a strong IT component, including an enterprise resource planning (ERP) system and transportation/logistics software.

“ had a lot of good ideas, but had not presented them to management in a convincing form,” explains Carter. “, we put together a detailed plan describing all projects we envisioned for the next five years, and their approximate cost, benefits, and timing. We had to show that we were doing it not just for the sake of doing it, but that the business objectives were strong -- to improve quality, cost, customer satisfaction, and productivity.”

The entire automation/IT effort was ultimately approved at the mill and corporate levels, and the five-year plan got underway in 1996. However, to insure project success, Jesup's request came with some unique stipulations.

Recognizing that many benefits from automation and IT projects are not predictable and often appear later as the systems are fine tuned, the Jesup mill lobbied Rayonier corporate to lower the expected initial financial return. However, managers within the mill were confident that certain results were achievable, so they rolled, and continue to roll, predicted results into the next year's budget Ð something Daniel describes as unique within the pulp and paper industry. “ other words,” Daniel says, “ official hurdle rate was lowered somewhat, but our expectations remained high and we haven't been disappointed.”

Combining process control and IT departments. Prior to instigating the five-year strategic plan, the Jesup mill's process control group functioned in isolation from the IT group, which managed business systems running on a mainframe and a few PCs.

In 1993, the mill had combined its process control, business systems, and PC network, and had formed one organization known as the information technology group. However, the individual mill areas continued to have little interaction until the five-year plan was invoked. By 1996, network, open systems, client/server, and distributed control had matured to a point where communication between the two areas was technically feasible, a fact recognized in the strategic plan.

In 1997, Jesup management hired the specialty pulp products director of IT, Hyder Ali. At that point, some process control projects had been completed and others were underway. Ali was first tasked with coming up with the detailed IT portion of the plan, as well as recruiting the required personnel. Ali's strategy entailed a phased plan of projects, with those capable of providing the most immediate business benefits scheduled first.

Carter and Ali devised the pyramid approach shown in Figure 1, where initiatives would simultaneously start at the top and bottom of the pyramid and meet in the middle via open systems technology and robust networks. Kindler is quick to point out that this sequenced approached has been crucial to the overall success of IT and automation projects.

“ this step-by-step plan, we could see how everything was integrated -- what came first, etc. -- so we did not start down paths and end up with systems that ultimately could not communicate,” states Kindler. “ It sounds simple, but being able to methodically Ôpick off' the pieces has made a huge difference in getting the necessary results.”

In the new control room, Jesup pulp mill manager George Hires (left), manager of controls and process information Horace Carter, and specialty pulp products director of IT Hyder Ali (right) address data transmission issues.

PULP COMPLEX PROCESS CONTROL. Rayonier has three separate fiber lines at the Jesup mill Ð Units A, B, and C. Unit A, installed in 1954 to produce high tenacity viscose pulps, now produces all of the mill's grades at a rate of 110,000 tpy. Installed in 1957, also for high tenacity viscose, Unit B now produces 160,000 tpy of hardwood acetate pulp. Unit C was built as a specialty acetate pulp line in 1972, but has since converted to a 280,000 tpy-capacity fluff pulp line.

As part of the Unit A and Unit B startups, eight batch digesters were installed with each pulp line, while 10 were installed with Unit C in 1972. In 1997, two more digesters were purchased for a total of 28 batch digesters.

Pulping complexity. In addition to grade change complexities when dealing with different wood species, other factors complicate production of specialty pulp at Jesup. For one, the mill is a prehydrolyzed kraft mill, meaning that there is an additional, prehydrolysis stage prior to the kraft cooking stage. Also, the exacting standards needed to produce hardwood acetates and high tenacity viscose pose more challenges, often requiring from four to ten phase cooks and individual cooks of up to five or six hours.

To meet the demanding specifications of its customers, Rayonier must closely monitor several parameters in its cooking stages, including variability of K numbers, which are used as a test at Jesup because of low lignin content in its chemical cellulose pulps. In addition, intrinsic viscosity (IV), a measurement of the cellulose chain's molecular weight, must match the specific application.

There are multiple bleach stages used in the production of chemical cellulose and fluff pulp. Because the Unit A pulp line produces a wide range of products and because Unit B is strictly used for chemical cellulose, their bleach plants are much more complex than Unit C. As with the cooking, the bleaching process for chemical cellulose requires extremely close attention so that pulp characteristics are not negatively affected.

Operations before automation. Prior to the start of digester automation projects in 1995, Rayonier was controlling its digesters using “ basic technology,” according to Carter. This involved single loop controllers activated via push buttons. There were 34 digester operators and each set of digesters could require up to three operators at a time, including one who had to manually replace the 1,000-lb cap with a pneumatic wrench after chip loading.

Carter notes that this amount of manpower was needed to hold the loops and coordination of the cook together, and describes the capping procedure as a “ and difficult working procedure” with safety implications.

“ saw that automation could improve our yield through reducing pulp variability, and that we could also better the productivity and safety of our employees,” comments Carter. “ operators could move into a process management capacity, rather than running around flipping dials and switches and manually capping digester vessels.”

Where to start? Because its Unit C fluff pulp line was the newest and least complex, Rayonier chose to first automate the 10 digesters associated with this line. Daniel says that it was natural to choose this more simple process in order gain experience before attempting the more demanding Units A and B.

Conceptual work began on the C digester automation project in May 1995. To control the digesters, Rayonier chose a Moore DCS. For the operator interface, Wonderware's InTouch PC-based product was selected, in part because it was an open system capable of supporting both the new Moore DCS, as well as the existing Fisher system in Units A and B, and the Allen-Bradley PLC in the woodyard. With this robust console technology, Carter says they were able to “” the operator interfaces across the various platforms so that operators did not have to learn all three.

The various DCS/PLC control systems communicate with a Wonderware I/O server, which is a PC running Windows NT that carries proprietary I/O software and boards. These boards allow communication between the appropriate controller and the operator consoles, which are also PCs.

To capture the knowledge of the operators and create control screens for the interface, Rayonier contracted with Orion Consultants & Engineering of Atlanta, Ga. Working with the local unions, everyone from area mechanics, electricians, and operators to control engineers and R&D provided input. By obtaining this knowledge, derived through years of experience, Carter states that the mill is “ to get the art out of it and get more science into it, while maintaining the process knowledge from both hourly and salaried employees.”

In addition to the hardware and software for the control systems, the digesters received temperature transmitters in the top, middle, and bottom of the vessels, as well as a pressure transmitter at the top and an automatic capping valve. In addition, new top and bottom valves on the outside of the vessel were added to help uniformly circulate liquor. All hardware was installed during regular maintenance outages to minimize downtime.

“ we chose to reuse a particular valve, we had to pull new wiring to it from the DCS system, and, while leaving our existing operation intact, plan a way to make a quick swap on an outage,” describes Carter. “, we would have the DCS sitting there all terminated on one end and, as we went into an outage, we would terminate on the field end, cut it all over, and start commissioning loops as we started up the digester, checking for functionality and performance. And that's how it went -- digester by digester, loop by loop.”

The actual commissioning of all 10 digesters occurred between mid-May and June of 1996, when the C digester automation was completed. Carter notes that detailed planning was required up front to insure that full advantage was taken of scheduled outages, when most of the transition work was accomplished.

Remaining digesters and A/B units. In July 1997, Rayonier sought to leverage its successful automation of the C digesters by automating the remaining 18 A and B digesters, as well as Units A and B, which would include distributed controls for washing, screening, bleaching, cold caustic extraction, and pulp cleaning. Although some Fisher DCS controls existed in the A and B units, they required upgrading to comparable levels of supervisory control used by the new Moore systems. For the entire A and B units, Fisher DCS and Allen Bradley PLCs are used, while Moore DCS are used for the C unit and all remaining digesters.

As with the C digester automation project, the mill's control system consultants developed functional specifications, working with operators, superintendents, and area mechanics to design the control screens. In January 1998, the mill began installing hardware and field instruments, though this was somewhat hampered by wet weather. However, pulp mill manager George Hires reports that the transition to the new control system for the A and B digesters, as well as the entire A and B units, occurred within two weeks “ very few lost cooks.” The digesters were completely commissioned by September 1998, and Units A and B followed in October.

Though Units A, B, and C now have distributed control, Daniel still regards the digesters as one of the mill's “ successes in achieving full automation, since all activities -- loading, liquor charging, cooking, and blowing -- are now automated.”

Integrated control room and Unit C. A key portion of the automation efforts at Jesup involved a new state-of-the-art control room that consolidates the control activities for Units A, B, and C. Work on the control room began in July 1998, at the same time that Rayonier was starting its work on Unit C, which included Moore distributed controls for washing, screening, bleaching, cold caustic extraction, and pulp cleaning.

The control room was designed by architects in conjunction with Orion Consultants for maximum ergonomic comfort and control accessibility. It features 28 control screens and 20 monitors, displaying video from throughout the mill. A small conference room resides in one corner, providing a discussion area.

According to Carter, this control room, which was completed along with the Unit C automation in July 1999, has been key in operator empowerment and cooperation between management and hourly workers.

“ are trying to drive problem resolution down to the lowest levels in our organization,” states Carter. “ the trending capability in the new control systems, the operator can analyze the problem and pull in the required people -- electricians, instrument mechanics -- or consult with his supervisor, who is now next door.”

Carter also notes that, by having all digesters and all three units controlled from one room, with operators “ each other in the eye,” there is more of a team effort to find and resolve the problem.

Other control system projects. Other process automation projects at the Jesup mill include: power management controls (February 1998), demineralized water plant controls (December 1998), and turbine generator controls (June 1999). Each of the projects involved installation of a Moore DCS.

Addressing employee concerns. Since the automation of the digesters, the number of operators has decreased by 30% in the pulping area, providing a cost savings for the mill and enhancing productivity and knowledge of the existing workers. While operators are now more enthusiastic with the equipment and their improved working conditions, this was not accomplished without some difficulty, given the headcount reduction, as well as employee concerns about the new systems' capabilities.

“ usually comes with the negative element of achieving a reduction, but we did up-front work with the union leadership,” says Carter. “ think we managed to acquaint people with the fact that, although the mill is in a small town in southern Georgia, it competes in an international environment, shipping pulp all over the world, and the lowest cost facilities with the highest quality are the ones that are going to survive long term. I think people realized that there has to be some pain involved in meeting and surpassing our competition.”

Adjusting to the reduction in force was not the only issue that the remaining operators had to confront. Hires points to understandable difficulty in transitioning responsibility to the control system.

For example, the system allows automatic scheduling of cooks where production is automatically put on line. At first, the operators would disable this feature. Now, according to Hires, they realize what a burden it relieves them of, putting them in a monitoring and analysis mode. Furthermore, there is currently only one person physically working in the digester area, and operators now have “ intellectual rather than a physical challenge,” reports Carter. He also observes that the operators have adjusted well to the new working conditions in the control room.

INFORMATION TECHNOLOGY TAPS PROCESS INFO. Since 1996, Rayonier has installed nine different business/information systems ranging from transportation applications to ERP modules. The software was selected based on its ability to provide the required business benefits, as well as its open systems capability. The system architecture includes the ability to communicate data both to and from the mill floor. In addition, to install and support the new software, the Jesup mill has instigated an aggressive employee recruitment and retention program for IT specialists.

Current information systems in use. Rayonier's most recently installed information systems include:

• CIM/21 data acquisition for deriving process information (July 1997)
• Tech Systems mill access controls (October 1997)
• In-house developed chip quality system (September 1998)
• Manugistics sales forecasting (October 1998)
• SAP customer order management module (December 1998)
• Baywood Technologies chemical management system (January 1999)
• TimeWare System time office system for automating payroll (April 1999)
• Solstace finishing management system (June 1999)
• Optum (MetaFreight) transportation/freight system (June 1999)

All systems were installed with minimal customization, including the ERP system. Ali notes that the mill “ to adopt the SAP business model rather than having the system modified completely to fit our business needs -- the source of many failed installations,” and describes only minimal tailoring of SAP's reporting capabilities. Because of their “ process flexibility” and resistance to system modification, Ali says the module was functional in just over a year.

Also, in keeping with the sequenced IT installations, the mill first installed the SAP customer order management module, rather than multiple ERP modules. The financial module is scheduled for installation in the next two years, and the materials requirements planning will start up after the financial module.

Robust network exploits process information. To allow users to “ down” to process information from their PCs, Rayonier has invested $2.5 million on network infrastructure alone. In 1993, the Jesup mill's process control, business systems, and PC networks were linked into one fiber optic-based backbone with Ethernet as the lowest deliverable cost network and TCP/IP as the network communication protocol. According to Carter, the “ of this network is integration along with standardized technology.”

For example, using data historian software, Rayonier is able to transfer process data to its business/information systems. Aspen Tech's Info/21 data historian acquires jumbo roll data from mill process control systems through Wonderware for the SAP customer order management module. Using open data base connectivity (ODBC), the data can be pulled from the data historian database into the Solstace roll tracking system. As the jumbo roll is converted to rolls or bales, the appropriate data is attached to that entity in the roll tracking system. When shipped, the specific roll or bale history is then passed to SAP.

Another example of data sharing capabilities between the mill's process control and information systems involves transmittal of grade specifications. Rayonier's R&D center provides manufacturing specifications for each new grade (see sidebar, “&D center optimizes quality with simulation technology”). These specifications evolve over time, so operators must obtain specification data when grade changes occur.

To do so, operators submit a query through Wonderware for the latest specifications. This triggers an in-house written structured query language (SQL) call for the information from the manufacturing specification system. A file is then transferred down through Wonderware and loaded into the appropriate DCS by communicating through the I/O server.

Users with appropriate permission levels can view process data from home via the Internet. Ali reports that they can see “ the mill is running on any level -- quality, production, even down to pH level of a vat -- and can trend and report on the data as needed.”

IT staffing. Though the mill received information technology support from corporate to install the new information system, Rayonier instigated an aggressive recruitment plan for IT specialists at the mill level. A human resources representative was dedicated to finding employees with the right skill mix. According to Kindler, the mill wanted specialists who were as much focused on business strategy as on IT.

RESULTS. In addition to the obvious cost benefits as well as employee safety benefits from less physical labor, the Jesup mill's automation projects have provided other tangible results affecting both cost and quality. The projects have surpassed the goals set for them, and the newer systems are currently being tuned for further gains.

As it approaches year four of its five year plan, the mill has spent about $20 million of the $30 million budget for automation projects. For information system projects, it has spent $7 million of a budgeted $15 million. Remaining IT/process automation projects designated in the five-year plan include production scheduling, financial/costing, maintenance management, warehouse automation, and utilities and machine controls upgrades

Some of the improvements from the digester automation projects are as follows:

Reduced K number variability. The mill is experiencing 35% reduced variability out of the A digesters, a 15% reduction from the B digesters, and 50% reduced variability out of the C digesters. Hires also reports that the improvements in variability have helped the mill smooth out its chemical demands.

Cooking efficiency. Automated scheduling of cooks has had an especially positive impact for the A and B digesters, where anywhere from four to ten cooking phases are required for chemical cellulose. Operators can give the system permission to proceed between cook phases based on certain criteria. Hires reports that, since the A and B digester automation implementation, the mill has set records for the number of cooks in one day, which amounts to roughly a 3.5% increase.

Rejects. Overall, the mill is between 20% and 30% better on rejects in cooking, with further gains expected as operators receive more advanced training.

Y2K compliant. Ali notes that, because of so much new equipment, there are hardly any Y2K issues for digester automation, and testing for existing equipment has already been addressed. He reports that the mill has “ made Y2K pulp.”

Bottlenecks eliminated. Automation of the more complex bleach plants in Units A and B has eliminated a nagging bottleneck for the high porosity grade. A 5% production increase was seen from automating a combined filtrate strength/seal tank level control scheme in the bleach plant.