The world is a batch

One of the best reference libraries on batch processing and the batch standard is the “WBF Body of Knowledge.” This reference library will eventually house all of the papers given at every annual WBF Conference. WBF produces two conferences per year, one in the U.S. and one in Europe. The 2006 WBF Europe Conference will be in Mechelen, Belgium, Nov. 13-15, and the 2007 WBF North American Conference, “Meeting of the Minds,” will be in Baltimore, Md., on April 30-May 4. More information on both conferences can be found at www.wbf.org.

ON AUGUST 15, 2006, Lynn Craig, of WBF (formerly the World Batch Forum) and a founding member of the SP88 Batch Standard Committee, and Maurice Wilkins, chairman of WBF, sat down with Control’s editor-in-chief Walt Boyes and talked candidly about the state of batch control and the batch standard.

Craig: We’re well past the tipping point. What we need to do now is bring a lot more people along, and we haven’t been terribly successful at it. WBF has, I think, provided a lot of information and help for people who want to understand. But we have entirely too many people out there in the industry who don’t understand the nuances of S88 yet.

Wilkins: S88 needs to get out to the other people it was intended to get out to, which include the process engineers and the plant engineers. It’s still seen as an automation kind of thing, and it needs to get out to the other guys who need to embrace it, too. Industry tends to see it as an automation thing, but it isn’t intended to be an automation thing. It sits in the automation environment, and it shouldn’t.

Craig: S88 is a beautiful, beautiful toy, and I call it that on purpose. It’s the kind of thing that management can understand, operations can understand, and process engineering can understand. It’s a tool for understanding amongst disparate groups. You have the modularity, so you can look at some grouping of equipment. You can talk about it. Everyone can understand what the other is saying. Too many of us in the automation world have been seen as the kind of geeks that speak a language that nobody understands, so “I don’t want to talk to them anyway.” This is a way to come out of the cave, and talk about how this process is going to run.

S88 defines a structure that can be used to understand most any manufacturing process, and can be applied to controlling and communicating about an awful lot of industry out there today.

I don’t think you can apply S88 to all discrete automation, but you certainly can apply it to a lot. You can also apply it, I think, to continuous. There’s a lot more to it that what’s written down in the standard. You have to interpret it for continuous process, but it’s very effective there. All it is doing is providing a structure to apply internally consistent procedural control to a manufacturing process.

I think in terms of applying S88 to a continuous process more in terms of the state that the process is in. Let’s face it, a continuous process has states. It has states during startup, and it has a fixed state where you’d like to have it run and never vary. What S88 does is provide the procedural control to get from state to state to state, until you’ve reached the proper state to run in. It’s a way to provide a control process from one stable state to another, desired stable state. It’s more than just starting up or shutting down. A lot of continuous processes will change products or grades on the fly. That’s a place where S88 can help a lot by institutionalizing the best practices and procedures for going from one state to the next.

Wilkins: I can upset the refinery guys by saying that the refinery process is one large batch. Batch was always seen as what you got relegated to when you weren’t good at doing the other stuff. It’s interesting that I’ve been schooled in both sides, and I find batch much more interesting. So to tell a refinery guy that it’s a big batch is a good way of upsetting him.

Question: Is that why S88 usage is lower in the petrochemical industry?

Wilkins: Yes. Batch has always been seen as somewhat inferior to their wonderful optimizers and things like that. Don’t get me wrong; those are wonderful control tools, but there’s a lot that batch can offer. There are so many applications and operations in a refinery or a continuous petrochemical plant that the batch standards could help with, but they just don’t use it. Oil movements are a good example. Startup and shut down of any one of a major unit, and recognizing and reacting to any abnormal situation…there is no common way that they handle those, and abnormal situation handling is becoming a big deal now. That’s something we have taken for granted in batch since the year dot. So I think there’s a lot of scope for the future there.

Craig: I think batch has an image problem, mainly because 10 years ago or a little more, batch was a process that generally speaking didn’t have a whole lot of instrumentation and control, and all of the procedures were done manually. People did batch, and it just didn’t fit into the high tech world. We fixed that with S88, but a lot of people don’t know it yet. S95 is there to deal with management of the entire manufacturing process. Manufacturing operations management is what it’s really all about. There are many different kinds of processes, many of which S88 can deal with. I see structured procedural control of continuous and discrete processes emerging as separate views of the same standard.