Stan: Many processes would be operating far below their capability if it was not for consultants with extensive practical expertise guided by a sound fundamental basis in the math and first principles of process control to see through the complexity often introduced by local excursions into patchwork solutions that are at best a distraction to the simple control solution. It is like these consultants have an overhead view of the maze, seeing the clear path to the end avoiding the dead ends. These people do not get the recognition deserved and their lessons are often lost over time. In Control Talk we are doing our best to showcase the achievements of individuals and capture the understanding gained the hard way by working in the plant and making sure the solution is sustainable and maintainable. It is our way of saying “Thank You”.
Greg: An exceptional example of this type of consultant is Sigifredo Nino, the founder and owner of Summa Control Solutions. Sigifredo worked five years at a coal-fired power station (EEB), 10 years with a pulp and paper mill (Smurfit), 13 year with Foxboro (pulp and paper, power generation, mining, industrial boiler, oil refining, petrochemicals), and for the past two-and-a-half years as an independent process control consultant with Summa Control Solutions, Inc. (oil refining, mineral processing, power generation, petrochemicals).
Stan: What is your philosophy and general approach?
Sigifredo: Process control is not just about the technology, but also the ability to question its soundness and the exertion of good criteria to either use it or reject it.
Process control is a very mature discipline, however, there are fewer and fewer people who really know what it entails to design a sound control strategy or even how to properly tune a PID controller. Superfast computers and fancy mathematical constructs will never replace the thorough understanding of engineering fundamentals and applied control theory.
While many authors have been trying to exclude mathematics and equations to make the field more “accessible,” I do actually tend to go in the opposite direction along with Roger Penrose: “The understanding that we have of the principles that actually underlie the behavior of our physical world indeed depends upon some appreciation of its mathematics.” (The Road to Reality – A Complete Guide to the Laws of the Universe, Jonathan Cape, London, 2004).
My approach to process control problems, paraphrasing Einstein: I always look for the simplest possible solution, but not simpler. Simple solutions work better and stay forever in service … except during the times when a field device fails, or there has been a change in the process, e.g., a bigger or smaller impeller in a pump.
Innovation is not only about new inventions, but also about using a technology existing in a field and then to apply it to another one. Innovation doesn’t mean to forget the fundamentals, and this is something I believe has happened to process control.
Finally and siding along with Greg Shinskey, who said: I have never found a problem I have not been able to resolve by using advanced regulatory control and PID algorithms; and control strategies that are not understood by the operators will be put out of service following the first malfunction.
Greg: My video recorded interview with Greg Shinskey at his home in New Hampshire featured in a special 2011 ISA Automation Evening session included a brief synopsis by Nick Sands, Terry Tolliver and me about what Shinskey meant to us in our careers. In the interview, Shinskey mentioned he was extremely proud of a protégé who was applying what he had learned from his books. That protégé turned out to be you. How did your relationship with Shinskey get started and progress?
Sigifredo: Since meeting Greg Shinskey in November of 1993 in Atlanta, when I attended to his “Process Control Systems” seminar, I have successfully implemented several of the control strategies presented in his books. And over the past seven years I have been privileged to work very close to him in several projects involving combustion controls, oil refining and petrochemical processes.
What has impressed me the most is seeing how his profound understanding of the chemical engineering fundamentals and control theory allow him to come up with brilliant and yet simple and functional practical designs.
Probably the first thing I learned from working with Shinskey is that the most important part in process control is the process. You can’t design or tune up a control strategy by treating the process as a black box.