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One of the greatest challenges facing the chemical industry in North America is dealing with aging process automation infrastructure.

In order to compete with chemical plants in emerging markets, these mature plants must update their older automation systems and strategies. New life can be breathed into these old plants with the use of newer automation technology, field-based architectures, and better process control strategies. The business results can be significant due to:

• Process plants that can operate effectively with fewer qualified operators.
• Automated plants that have less operations related errors.
• Modern control systems that can handle many tasks quicker, safer, and at a lower cost than a human operator.
• Advances in automation system technology that allow plants to operate longer without downtime.

However, in a highly automated plant with sophisticated, modern process controls, there are additional complexities that need to be addressed.

• The role of the operator is different and more difficult. He is asked to monitor a sophisticated system and make decisions about the health of the process and the performance of the system based upon trends and meta-information (information about information).  In many cases instead of actively doing something, the operator is put into a position where he has to review the information presented and make a decision whether he should do something or nothing.
• Because the system and process are more reliable, operators may seldom or never see upset conditions and can quickly lose critical skills necessary to deal with those situations. An inexperienced operator on a highly automated control system can easily make a mistake that can cost the plant significantly.

In addition although modern, field-based automation have great reliability and performance there are risks that affect any automation project, regardless of the technology.

• Hidden errors and issues in the automation system application software can remain undetected until they cause process or operational issues.
• Actions taken by operators can be inappropriate causing risk to the process or plant operations. Conversely, operators not taking action when they should can cause similar problems.
• Operating procedures that  are in error or incomplete such that they are not used or trusted, can cause inconsistencies in plant operations.  They are also a weak link in the operation of a chemical plant that can be uncovered in regulating agency audits.

In Automation Vision Comes to Life, Carl Stumpe from BASF, describes a migration from an aging distributed control system to a modern field-based architecture.  One of the core strategies to make the controls modernization a success was to incorporate MiMiC Simulation Software into the project execution plan for application software testing and operator training.  Specifically, BASF used this enabling technology in several ways.

• A Virtual FAT was administered using MiMiC to thoroughly test the control module functionallity.  Along with a clever approach to verifying IO terminations with test fixtures, this eliminated the need for most loop testing.
• MiMiC was also used to test process interlock functionallity.  Again, this saved considerable plant time and also allowed more complete interlock testing than was possible on previous projects.
• Operators were trained with a combination of formal instruction and open time on the MiMiC simulation allowing them to build knowledge of the process and confidence in the new control system.
• Control strategies were optimized as well using MiMiC Simulation.  Because MiMiC models are accurate, dynamic, and real-time, BASF was able to modify and debug several control loops that never worked well on the older legacy control system.

The business results of using MiMiC simulation for this control system modernization were reduction in downtime and better product quality.  Although they estimated originally 2 weeks of downtime to perform the cutover, Carl's team took only 10 hours.  This saved significant production costs.  In addition, because the control system was thoroughly tested, product quality and yield was better than the older control system.

Other Resources to Review

ARC Position Paper - Using Simulation to Optimize Results of Automation Projects
Software Acceptance Testing with MiMiC Simulation Software
Operator Training Systems Using MiMiC Simulation Software

We look forward to your comments, questions, or suggestions.
Hope to hear from you soon.

Mart Berutti, 11/23/09