Dustin Beebe, ProSys
The new year is upon us. Even though we are just a couple of weeks into 2017, for many of us, the firefighting of everyday issues has begun. We all have dreams of managing our most precious commodity – time – better than last year, so I will be concise. Both for us and our respective companies, how we utilize our time can have a big impact. I will start with an area most control engineers and companies spend too little time on.
Goal: Complete one optimization project more than last year
Reason: Make money
Results: Improved profitability
Probably the single most valuable area for us to spend our time as control engineers is optimization. There are always good reasons why we don’t get around to it – Alarm Management, control system migrations, etc. Before we know it, time has passed and new optimization schemes or controllers have not been implemented.
One of the most erroneous statements that I hear regarding this is “You have to have a great base layer then you can start working on advanced.” Here are two problems with this statement:
- Basic control work will never end. In any process plant that is making money, there will always be process adjustments and capital projects that will keep any control engineer busy. Use advanced controls to focus and prioritize improvement to basic controls.
- This statement actually undervalues the role that basic controls play in optimization. What is the objective of the basic controls? What are they supporting? They need to support advanced controls. Would you lay the foundation of a house without floorplans for what you are building on it? You have to have more than just a foundation to build a house.
Procedural Automation (also known as State Based Control)
Goal: Design an automated procedure for at least one equipment group
Reason: Improved safety and process reliability
Results: Reduce operator exposure and improve reliability of response in critical areas of operation
One of the most exciting things happening in process control is the re-discovery of Procedural Automation. Procedural Automation is enabling a whole area of Automated Operating Disciplines that allows us to approach the control of continuous processes in a manner that supports safe and reliable operations. The single most damaging concept to process control is that of single loop control. We have to view process controls holistically. Limits of the process operation need to be defined. Controls need to operate in a coordinated manner to maintain these defined operating limits while driving the process toward the desired state.
Here is a Cliff’s notes version of Procedural Automation (State Based Control):
- Select an equipment group (column, heater, compressor, evaporator, etc.)
- Define the operating states for the group
- Determine the operating limits
- Design automation to maintain operating limits while driving the process toward the desired state
For more on State Based Control, read our whitepaper on Changing Your Board Operator to a Process Manager.