Football and Advanced Process Control (APC)

Recently, I came across footage of an old Cricket match, where there was an intense contest between the batsman and the bowler, who happened to be a leg-spinner. It was difficult to tell who was better. Finally, on one occasion, the bowler found a way through, when he saw the batsman stepping out of the crease: he just changed his line and length, and the batsman was beaten, only to get stumped out by the wicket-keeper.??

In Football, the situation gets a little more complicated. Unlike Cricket, where there are eleven players on the fielding team trying to control the two batsmen, in Football, the contest is going on all over the field. The striker, the midfielders (central, defensive, and attacking), the goalkeeper, etc. Each one of them is trying to get the better of their counterparts. With fierce competition naturally comes aggression, and there are often sparks between the players on the field. Among all this chaos, there are certain rules to be followed. Also, the two half-times need to be completed within the specified duration. And to ensure that it all goes smoothly, there are referees!

Now let’s consider a chemical plant as a football match. There are various processes going on simultaneously in various units, such as feed input, heating, cooling, reactions: just like there are small contests going on all over the field in Football. And in order to ensure that they proceed in the desired way, there are various (PID) controllers looking after the variables they are supposed to control, such as temperature, pressure, level, flow, etc.: just as there are players performing their respective roles at various positions. The desired result is, of course, to produce the product: just as in Football, the aim is to strike a goal and win the match.

However, there is a subtle difference. In a conventional chemical plant, the (PID) controllers are working independently, each one targeting only a limited number of variables at a time. Again, there are many constraints that need to be followed, such as operating only within the specified ranges of temperatures and pressures; not exceeding a certain allowable energy consumption, not producing an off-spec product, etc. Now introduce a referee to this system. Whereas in a Football match, the referee ensures that the rules are always adhered to, and the duration of the game does not exceed, in a chemical plant, a referee ensures that the operational constraints are followed, and the desired output is achieved.

In a little sophisticated term, this referee is called the Advanced Process Control (APC)! This entity ensures proper control over various (PID) controllers all the time, the operational constraints are not violated, and the desired result is achieved smoothly. This desired result might be any or all of the following: reduce energy consumption, increase throughput and yield, enhance safety, maintain product quality. Being in existence for quite a while now, and as a mature technology, the benefits of APC are well established and they stand out even more prominently in today’s VUCA world of shrinking profit margins.

We will discuss more on this in our next article.

Author-

Dr. Tushar V. Tamhane Delivery Head, Advanced Process Solutions Group, Tridiagonal Solutions

Tridiagonal Solutions?is a process consulting company, providing solutions to the industry verticals like Pharma, Food, and Sp. Chemicals. It leverages a physics-based approach (CFD/DEM) combined with data-driven modeling techniques for better process understanding of various unit operations (for e.g. mixing, coating, drying, milling, etc.). It offers decision-support solutions for scale-up, Tech transfer, troubleshooting, etc. by creating performance metrics of assets vis-a-vis?quality.?

Email - [email protected]