Completely automate and eliminate operators?
By Bill Lydon
Completely automate and eliminate operators? I believe the answer is obviously “no,” because well-trained operators provide an advantage by ensuring efficient and safe operations. Process plants are complex, and the majority of those in operations management agree good operating people are valuable. Automation professionals can support knowledgeable operators with well-engineered system applications to keep production running efficiently, particularly when seldom-used procedures are required and unexpected problems occur. Automating and clearly documenting functions that are well defined and deterministic enable operators to focus on the most important tasks, problems, exceptions, and unexpected issues. Automation professionals can take advantage of ISA 106, which is focused on achieving these goals with standards, recommended practices, and technical reports on the design and implementation of procedures for automating continuous process operations.
The ISA 106 models define how to capture information about physical assets, from the enterprise level down to an individual device, and the requirements that define a procedure. They establish the functional requirement for the automated procedure and tie these requirements directly to objects in the physical model. The lower the level, the more detailed the association between procedures and objects. The implementation module defines a set of ordered tasks, which may have their own subtasks to perform step-by-step actions in a defined order. There are three elements contained within each task:
- command: something to trigger the individual action,
- perform: do the action(s), and
- verify: confirm successful completion of the task.
Each task’s command-perform-verify sequence can include a mix of automated and human operations as appropriate for the specific assignment. For example, a human may need to verify if an automated task has been performed correctly, or vice versa. After each command has been performed and verified, notification is sent to the next task in sequence.
Larger activities, such as plant startup or shutdown, are important, but the same tools can be used for more routine procedures, such as isolating and starting up a redundant pump system, performing online maintenance of a piece of equipment, or even something as “simple” as performing an in-line valve performance test; all of which normally require communication with someone physically at the asset to verify, or in some cases manually intervene in, the process.
Procedural automation can be used to capture and share corporate knowledge, including best practices, and to minimize errors with a resulting decrease in incidents, improved safety, and higher throughput. This is particularly important with an aging workforce and the difficulty in finding experienced operators.
Procedures represent the knowledge necessary to operate a system and are critical components of continuous operations. Historically, procedures have been executed by humans reading from a manual, checklist document, or a static display. The ISA 106 technical report describes the concepts by which procedures are integrated into the basic process control system (BPCS).
The intended audience for the document is technical and operations managers and engineering personnel who are responsible for the operation or automation of continuous process operations, members of engineering departments of owner/operators, engineering personnel of engineering and procurement companies, automation vendors and system integrators, and other process engineering practitioners.
Safety statistics show the majority of incidents not related to outright mechanical failures happen during abnormal situations, primarily unit startups and shutdowns. For example, the Kern Oil Refinery fire in January 2005 occurred during a crude unit startup, and the BP Texas City disaster in March 2005 took place during the restarting of a hydrocarbon isomerization unit. Unfortunately, there are many more examples.
The recipe for disaster is when an infrequent operation is required, but the key individuals are not available, leaving inexperienced operators to follow inadequate or incorrect instructions. Something can get out of control, leading to an abnormal condition with the undesirable outcomes of equipment damage, environmental release, injuries and fatalities.
Procedural automation benefits
- improved safety
- improved startups and shutdowns to improve efficiency and throughput
- efficient transitions to increase production and quality
- improved disturbance recovery
- capture and retention of “tribal” knowledge
- improved communications with common definitions and terminology
By applying ISA 106, a single process plant, a complete facility, or even an entire company can achieve significant improvements in operational efficiency and safety.
For more information, visit www.isa.org/isa106. For information about the ISA106 committee, contact Charley Robinson, ISA standards, email@example.com.