1 April 2005
Mill in real time
Paper plant finds answers from disparate sources.
By David Stockford
Pulp and paper mills are incredibly complex manufacturing environments.
The real-time data and events needed to effectively optimize mill operations are typically locked up in a variety of automated systems that consist of quality control systems, distributed control systems, programmable logic controllers, lab automation systems, product tracking systems, enterprise resource planning systems, information technology (IT) infrastructures, control system historians, and others.
A real-time performance management (RtPM) system is an events-driven platform that provides the capability to gather and analyze real-time data and events from disparate sources across multiple operations, transform the data into specific relevant information, and deliver unified, role-based portal views of the information across the enterprise. Key elements of an RtPM system include automated data and events collectors, networked data storage, hierarchical data modeling, business analytics, data distribution, and data visualization. The RtPM system provides the technical capabilities. However, the corporation must reengineer business processes to gain the maximum value from the technology.
Events and data generate from a widely diverse set of components. The RtPM platform provides proprietary interfaces required to collect and aggregate the data into a common platform.
Moreover, bi-directional gateways correlate information stored in corporate enterprise systems and, in return, supply aggregated real-time data to these systems using technologies such as ODBC, OLEDB, XML connectors, and Web services.
Networked data storage
A large integrated pulp and paper company may need to store 1 to 2 million separate data streams recording thousands of data points per second, at a large number of different and geographically disparate locations, all at their original resolution, and maintain the data on-line for three to five years or longer. The high performance data storage infrastructure in the RtPM system is able to store the data locally (e.g. at a mill site) and corporately while providing high speed corporate-wide access to all of the archived data. Reliable data storage and simplified availability of that data across the corporation enables more accurate and informed decision-making and accountability.
You can unlock the hidden value in the vast numbers of data by using the hierarchical data modeling in the RtPM system to organize the information into groups for use in programs and displays and into real world models easily understandable by the users. For maximum effectiveness, a contextual modeler organizes data in modules that allow users to define properties, aliases, headings, and layers. A typical example is a "family tree" structure used in the management of event-driven and batch processes.
Equipment, operations, and phases can group in a unified hierarchy and data streams identified by referencing actual pieces of equipment and manufacturing processes. The modeler accommodates links to information related to each process unit or piece of equipment such as MSDS information, operating procedure data, equipment drawings, or maintenance records. The modeler also maintains "versions" of the hierarchies so users can review historical data via aliases in the context of the hierarchy that existed at that designated time segment. This allows a user to accurately search historical records related to a customer order even though the equipment configuration was different than the current configuration.
Analytic tools can reduce and transform the data into actionable information. Key components in the RtPM analytics toolbox include an advanced calculation engine, batch analysis, event analysis, process templates, wizard-based Visual Studio.NET integration, and integration with Microsoft's .NET XML Web services. An advanced computing engine allows users to carry out complex calculations (with minimal programming) for asset efficiency analysis, cost accounting, and batch summaries, among other functions. Ideally, you can write these programs once for a particular service, then run simultaneously over multiple, similar tools or processes such as batch analysis. The wizards make these processes easier to program, reducing the need for costly high-level programmers and keeping operations costs down.
Actionable information needs rapid delivery, locally in the mills and globally across the entire corporation. It needs to get to the right people who need it to collaborate in real-time on business issues. RtPM provides power users in the mills with easy-to-use tools for transforming real-time information into PC-based dynamic displays and analytics (spreadsheets). Web-based displays and analytical tools aid in role-based distribution of information across the corporation. All displays or analytics available locally are also directly accessible via web tools avoiding the need to produce the same information twice.
Easily configurable RtPM data visualization tools transform actionable information into pictures, graphics, and trends that deliver the information in a form appropriate to the individual. These tools have the capability to produce widely available "standard locked down" displays and analyses as well as "ad hoc" individual versions for on the spot trouble shooting.
RtPM provides excellent returns on the investment in substantially increased efficiency, higher revenues, cost reductions, and better customer retention from superior service. However, corporations need to reengineer business processes to take maximum advantage of the new capabilities gained from implementing RtPM. Good corporate-wide planning of the implementation, strong involvement from operations, and on-going support from engineering and information technology groups are essential to the success of the reengineering process. Using an integrated RtPM platform based on company-wide accepted standards goes a long way toward getting various departments on board, providing support for a successful reengineering effort with minimal disruption and immediate results.
Business of paper
Efficiently managing the purchase and usage of energy is increasingly critical to profitability in the pulp and paper business. Over the past few years, deregulation and other factors have doubled, and in some cases tripled, the cost of energy required to power the various operating units. Companies become overwhelmed trying to gather and analyze the data needed to manage energy costs and remain profitable.
In 2001, with deregulation looming in the Ontario Canada electric power market, executives of a large newsprint producer decided to implement an RtPM energy application to automate the data gathering process and centralize the information from and between the various mills and operating units.
Their objective was to give operations and executive management a comprehensive real-time view of energy usage patterns across the company and the opportunity to take corrective actions before they had a negative impact on the bottom line.
Historically their five Ontario mills purchased more than $80.7 million ($100 million Canada dollars, or CAD) of electric power annually, making this Canadian-based company the largest single user of electrical power in the province. With anticipated wide pricing swings in electric power they realized poorly managed power purchasing could potentially cost the company hundreds of thousands of dollars. They needed an enterprise-wide energy management system to enable the mills to track electric power consumption in real time and to place this information in the context of energy market pricing, so they could make smart power-purchasing decisions.
The company was able to develop its own energy management system at a fraction of the $2.4 million ($3 million CAD) price tag of an off-the-shelf system by using RtPM systems already in place at four of their five mills and by tapping the programming talent of key staff members. The RtPM systems, already used for managing production at the four mills, would collect the data from the various mill systems required for the energy management project. The project had wrap up ahead of the May 2002 deadline, only six months away.
The company added an RtPM system at their fifth Ontario mill and implemented a second system at corporate headquarters to serve as the control center for the entire power management application. Data links and interfaces were set up between the remote servers in each mill and the corporate system.
The next step was to link the system to electricity market information and other pertinent data that was available on the Internet. A HyperText Markup Language (HTML) interface connected the RtPM systems to a Web site operated by the Independent Electricity Market Operator (IMO), a not-for-profit organization formed as part of the restructuring of Ontario's electric power industry. The IMO site provides real-time spot market electric energy pricing, as well as hourly pricing and next-day pricing forecasts. A link was also set up to the Environment Canada Web site to collect real-time weather information that could impact electric power pricing. Connections to other Web sites provided data on natural gas and crude oil futures markets.
Work began on the project in October 2001 using programmers and specialists temporarily assigned from various company locations. The energy management system wrapped up in less than six months, in time to meet the deadline, and with a total budget of just $62,122 ($77,000 CAD). The system proved to be an invaluable cost saving tool for the mills, enabling them to see and react to fluctuating energy market conditions swiftly and effectively. For example, during the first year of the system's operation, when IMO pricing reached a peak price of about $800 per MWH (compared to $43 per MWH prior to deregulation) one Ontario mill reacted quickly to alter its production operations to reduce power consumption.
For mill personnel, the heart of energy management system is the control center screen, which allows operators and managers to look at any of the five Ontario mills to make comparisons between their planned demand and their actual load consumption. Staff can also monitor current and projected electric energy prices, aggregate demand for the whole Ontario power grid, prevailing weather conditions and forecasts, and energy futures data. Weather information drawn from the Environment Canada Web site is an important planning tool since forecasts for very cold or very hot weather in Toronto can drive up demand and subsequently the price of electricity.
One important system component is the load-planning module. This module covers all heavy equipment for each mill, such as thermo-mechanical pulp systems, refiners, paper machines, and winders. The base load configures for every piece of equipment according to how many megawatts of power each machine consumes when it is running at full speed. The load plan screen allows users to call up data and see at what percentage utilization different pieces of equipment are scheduled to run and for what period of time, down to 15-minute intervals. Managers can then adjust production schedules for differing strategies to match power pricing and forecasts by re-configuring the percent utilization and operation schedule for each piece of equipment.
Three of the five Ontario mills have their own hydroelectric generating capacity. Typically, they reduce their power purchases by producing their own electricity during the day when prices are higher.
During the off-peak periods, such as night time, they keep the water and buy electricity. These mills can also choose to shut down parts or all of the mill equipment in favor of making and pushing power to the grid at current market price if the market is very high, for example at $200 per MWH. Management may also switch paper orders from one mill to another based on electricity cost considerations.
The energy management system does not replace mill management involvement in the decision making process but simply and effectively equips them with additional information for better decision making.
The company credits the system with enabling energy savings at the five Ontario mills estimated at $806,000 ($1 million CAD) per year.
Optimizing within a pulp and paper mill site is complex; attempting to optimize operations across multiple geographically dispersed mill sites is even more complex. Everyone knows the consequences of poorly optimized enterprise operations—increased production costs, lost revenue from the inability to meet customer requirements, etc. Management, in the mill and at corporate locations, needs a common view of operations to effectively respond to dynamic changes in the market, make production adjustments, and improve product quality.
A global producer of packaging and coated and specialty papers installed RtPM systems at 15 major manufacturing sites collecting over 650,000 data streams and deploying over 2,000 user licenses.
Some of the operational benefits included:
- Close monitoring of bleach plant performance to minimize excess emissions and avoid cluster rule violations
- Annual cost savings of $250,000 from closely monitoring chemical variability and usage
- Minimizing downtime by immediately alerting supervisors via e-mail when a sheet break occurs on a paper machine or a piece of equipment fails (e.g. the pumps that supply water from the river)
- Tracing quality problems to equipment by analyzing downstream quality data, like mapping historical caliper profile data in two dimensions to detect the gradual degradation in the calendar stack rolls and determine when they need to be changed
- Capital cost avoidance by providing corporate research with the ability to centrally analyze the utilization of equipment processes and determine the actual need for additional process equipment
Calendar-centric maintenance has been accepted practice in the pulp and paper industry for decades.
However, in today's competitive environment, optimizing existing equipment assets and delaying costly capital equipment expenditures are essential to compete. The inefficiencies of calendar-based equipment maintenance are too substantial, making it critical to implement a condition-based asset management system that gives engineering and operations the ability to track equipment performance in real-time.
A Canadian newsprint and specialty papers mill initiated a recent project to expand the use of their RtPM system to do condition-based asset management. A basic care package and a work management system had been in place since the early 1990s, however most routine mill maintenance was calendar-based (filter change, lubrication, etc.). Most process maintenance was reactive/corrective maintenance, driven by the "squeaky wheel" philosophy (lab complaint, customer complaint).
Custom RtPM interfaces installed in over 10 mill automation systems to collect the required real-time data. Users established rules for condition monitoring in the RtPM system, and events triggered by these rules became action items that integrated and tracked via the mill maintenance module in the company's enterprise resource planning system. Metrics were set up for measuring performance success in the combined operations maintenance system.
Today, using condition-based asset management, an engineer can monitor over 1,000 process variables and over 500 motor/pumps for performance, and through integration with the mill maintenance system, issue automatic work orders where equipment is performing below par or process variability is too high.
A well-tuned regulatory control and properly functioning instrumentation layer is a must for sustained benefits from advanced control. Documentation of the maintenance of the mill process equipment (physical assets) was not a problem, but maintenance of the mill's process control loops, which has more benefits, typically did not happen. A comprehensive system to proactively identify poorly performing control loops and better utilize instrument maintenance personnel was implemented as part of the condition-based asset management program. The system now monitors over 900 control loops for performance, and automatic work orders are released for poorly performing loops.
Behind the byline
David Stockford is a business analyst with OSIsoft in San Leandro, Calif.
Return to Previous Page