In this completely integrated mill, the architecture and its digital system control more than 2,100 Rockwell Automation (www.rockwellautomation.com) E3 and E3+ motor control centers (MCCs) through DeviceNet, more than 3,500 discrete remote I/O points through Profibus DP, and more than 340 variable-speed drives though Profibus DP. The DeltaV system also interfaces with more than 15 PLCs through Profibus DP and special analyzers through Modbus. Emerson also provided Foundation fieldbus consulting, standard definitions and automatic database generation and other services.
A Microsoft Access application was developed to provide output for configuring the digital automation system directly through an ODBC connection. Information on all system I/O interface cards, Foundation fieldbus cards and devices, Profibus devices, DeviceNet devices and single I/O channels was captured in the application. Indexing and integrity checking was performed to detect possible errors and loss of data.
A simple form provided the ability to assign I/O interface cards according to availability of their respective carrier slots. Once the I/O slots were loaded, the form was used to allocate Foundation fieldbus, Profibus or DeviceNet segments to available interface ports. A subform showed the list of devices attached to any selected segment. With all the buses assigned to corresponding I/O card ports, the final step was to create tables for bulk export to the DeltaV digital automation system.
The application provided the option to select which type of objects to import into each process. Special reports were created for hardware integration and system configuration. Others with more detailed information, such as physical location for each signal in control cabinets, device settings, instrument ranges, etc., were used for software configuration.
This automated approach to the database generation greatly reduced the amount of time required for configuration, resulted in an error-free database population and provided a source of information that was re-used for documentation and training, simulation and test sheets.
Digital Technology Speeds Configuration and Start-Up
"A very good example of the benefits of digital bus technology is provided by the intelligent motor control configuration," Erazo said. "In previous projects where we had no intelligent motor controls (MCC), configuration of a complete MCC for 30 motors could take two weeks to one month. Now it takes just half a day to do the same job.
"Configuring a valve is also much faster than before. On previous projects, we could spend up to half a day trying to get a valve to move to the chosen setpoint as part of the calibration process. Today all we have to do is press a button and it self-calibrates. If a problem ever occurs with the valve, we can get the diagnosis immediately. By using Foundation fieldbus and the diagnostic capabilities of the predictive maintenance software, we can quickly determine whether the problem is with the actuator or the transmitter, or if it's only a calibration problem."
Juan Jorge Cáceres, maintenance manager, adds, "A key advantage of the predictive maintenance software is the amount of information it provides. It tells us the state of calibration and if there is a malfunction, such as an actuator problem in a valve, so that we can fix it before it forces us to shut down parts of the plant. The advanced diagnostics also help us prevent damage to the environment and increase the utilization of the plant."
Erazo added: "Digital bus technology makes it possible to do our diagnostic and often our repair work from the main control areas rather than on the ground. Wireless networks enable our technicians to go all over the plant with their laptops, testing equipment much faster than in the past. We had practically no errors in the digital automation system, and we started up the plant successfully and quickly. The technology made configuration of the plant easier."
To further ensure smooth start-up, Emerson performed off-line testing using high-fidelity simulation to validate operations and configuration and to familiarize operators.
"We checked all the logics programmed in the digital system for the different areas, area by area, together with the vendor of the associated machine," said Erazo. "We did it by simulating the real process in the plant, so that we could be 100% certain that the logic was good, and we wouldn't have any problems during start-up.
In addition to simulator training, operators found consoles easy and intuitive. "I didn't take a training class on how to operate with the system, but it turned out not be necessary," commented Marcos Vidal, superintendent in the mill's liquor area. "That's because the system is very easy to operate. It's very similar to Windows. Built-in diagnostics make it easy to detect and determine the cause of problems."
Project Has Met Its Goals
"Our priorities are the safety of our people, the environment and production," Quintana said. "The system, along with all the associated connectivity tools, diagnostics, smart controls etc., has helped us achieve these goals. The system is open and provides a wide range of connectivity so in the future it will allow us to continue developing and expanding, and taking advantage of the communication standards in the market."
"Start-up at Nueva Aldea went according to plan," Luks said. "From the beginning, we began to plan the installation of the equipment from the point of view of risk matrices. We assessed all the risks that each stages of the operation could face, from receiving and start-up to production at the factory. This created a level of concern and attentiveness that has made it possible to operate not only without major accidents. but practically without any incidents at all.
"We adopted a gradual start-up curve that meant we had control of the processes at all times, maintaining as top priority personal safety and environmental protection, and we were able to achieve our goals," continued Luks. "Our environmental performance is so good that we will soon be able to generate additional revenues by entering the carbon offset market. The equipment and control technology used have helped us achieve prime quality from the first days of plant operation."
Luks concluded, "The plant is designed to turn out 856,000 tons of cellulose a year. By April, we reached 93.8% of that target on a monthly basis. Digital technology has helped us reach this production level while maintaining the safety of our people and of the environment. As with all projects, this one demanded much dedication and energy on the part of all the participants. Despite the huge scope of this project, it was completed on time largely due to the great support we received.
"Following the successful start-up, we have continued to increase our output in a sustainable way allowing Nueva Aldea to become a development pillar for the entire region."
Juan Jorge Caceres, Alejandro Erazo, Marco Vidal Cruz, Mauricio Quintana M, and Gunars Luks Guzman are all employees of Celulosa Arauco Nueva Aldea.