Process Simulation Use Report
Research respondents say operator training is the most important use of process simulation software. This reflects changing day-to-day operational realities.
While computer-based simulations can take many forms, in the industrial space, one of the most common is a process simulation where a computer takes the place of an actual running process plant. In an effort to find out who is using this type of software and how they’re using it, Control Engineering launched a survey in January to gather information. This product research survey was closed in February with 137 responses.
The top three responses to the question, “Why did your company invest in simulation software?” all centered on training-related issues:
To train new operators in existing infrastructure (52.6%);
To learn new, unfamiliar operations (44.5%); and
To protect assets through better-trained operators (41.6%).
When considering a follow-up question, “Have simulations since been used for other purposes?” the highest scoring answer by far (61.3%) was “Improve process performance/reliability by experimentation.” The notion of having a tool to explore process improvements without risking equipment or production is very compelling. Creativity seems to run out quickly since the second highest answer to this question was, “don’t know or none,” (32.1%). Nearly a quarter of respondents (22.6%) did report additional uses including “sure analysis, demand management, capacity planning, etc.”
One of the more interesting responses had to do with sources of simulation software—the interesting part being that no single provider represented even 10% of the companies named. The top four suppliers combined account for only 25.6% of the total. (See graphic.) After sorting through the write-in responses to the “other” option, at least 40 sources were named. Moreover, many companies report that they wrote their own process simulation software; when combined, these variations make “created in-house” the second-highest source of simulation software.
“Features” lead the list (49.6%) of answers to “Why did you choose this provider over others?” Other motivations included “cost” (34.3%) and “familiarity from past work or university experience,” (28.5%).
Training in proprietary processes
Given their dual purposes of training operators and exploring process improvements, it is important that simulations provide as realistic a facsimile of the real control system and process as possible. When asked, “Does your simulation environment incorporate proprietary process equipment or thermodynamic models?” 62.0% said yes. Additionally, 51.8% reported that their simulation system uses the actual DCS/SCADA system graphical user interface, rather than a generic interface.
The survey also asked which tasks and operations were covered within the simulator. This was a written-in response and had many variations, but an idea that appeared frequently was that all elements are included. There were comments like, “Everything in the DCS is simulated.” “All tasks done by operators can be tested.” “System is supposed to cover ~90% of all control room operations.”
One user remarked, “The simulator emulates the plant operating board and has the look and feel of the actual plant itself. Since we deal with reactive chemicals, we can hold training sessions with operators to experience very abnormal conditions, and the corrective measures required to prevent or minimize undesirable consequences. The plant’s reliability is approaching 99% and with 50% of the operators at the five-year or less experience level, it is imperative that the simulator is used frequently enough to give them the experience they would not otherwise receive. This application accelerates the required learning and gives the new board operator confidence that he or she needs to get through an upset—making the right decisions and moves at the appropriate time.”
Most simulation systems are used in “heavy” process industries, with oil, gas, petrochemical, and chemical plants accounting for 54.7% of users. This was followed by smaller segments in food & beverage and pharmaceutical at 5.8% and 2.9% respectively. This leaves a large group of “other” at 36.5%.
Value of simulation
When asked, “What value do you receive from the process simulation software?” respondents wrote in a variety of observations, including training and testing:
The act of performing a process provides the operator the ability to know, understand, and appreciate his/her role in a situation in a manner far beyond that in which simple classroom instruction can accommodate.
New operators can get extensive hands-on experience with the DCS without affecting the production unit.
Has been a big part of new operator training (last year we hired 15 new operators to cover retirements). This year will be expanded and used in ever-green training.
Better trained operators, especially for the operators who have had to advance quickly up the ranks due to retirements at the top.
New operators learn more quickly how to conduct the plant. They also learn the interactions in the plant and the consequences of their acts. Experienced operators are kept up-to-date.
Reduced severity / duration of process upsets due to operator training on emergency scenarios.
Testing of control system configuration/logic. Ability to run operators through scenarios and evaluate if design will meet expectations of operators.
Reduced commissioning time for new DCS and SIS systems.
DCS configuration development and checkout.
Control strategy development and evaluation.
Any software that is supposed to reflect an actual system has to be maintained to keep it current. When asked if the simulator is maintained on a regular basis, users had many responses ranging from constant updating to “unchanged for five years.” Others reported that it is updated in connection with specific projects or control system improvements. Some cited specific constraints and opportunities:
Maintained for current projects at this stage. Will look to use for ongoing capital and project support and possibly maintain full plant process simulator. Control simulators will likely be only for project duration.
Considering use for operator training however we may have missed that opportunity on our largest project.
The simulation is not maintained on a regular basis due to resource limitations. It is only updated during projects.
While engineering was still programming the control system, it was updated frequently. When the plant went hot into operations it was left as is, and was still used for periodic operator training.
The client organizations that value simulation will maintain their simulators. In the present economic climate, those that do not, do not even attempt to purchase these products.
There is always lag time between certain modifications and the simulator. For any major changes, the simulator upgrade is part of the project.
Advice from those who’ve been there
Ultimately the most telling question asks, “What else would you tell a peer about your experience with process simulation software? Is it worth the investment or not?”
Answers took many interesting directions:
I don’t design any control strategy without having a simulation to test against. It is invaluable for DCS checkout and operator training on any new plant. Almost essential for testing batch process control configuration.
Working with all of the vendors of the real controls to aid the simulator vendor in development is a very major problem as each wants to sell you a simulator for their unique portion of the total system. Return on investment should be analyzed on a case by case basis.
One saved shutdown saves the investment several times.
General feeling is that unless there are some serious multivariate relationships in the chemical reactions, our lab and small scale pilot equipment provides sufficient data to scale up to production equipment.
Keep your expectations under control. Simulation software can have a steep learning curve.
It adds 25% to the cost of developing the control applications but saves a lot of time at commissioning and start-up.
With the high expense of our product, the simulation software is a cheap way to reduce risk.
Process simulators must have buy-in by the major stake holders to commit the resources to use, support, and maintain the simulators otherwise they quickly become out of date.
For our small plants commercial software is too expensive and takes too long to configure.
It is worth investing in one but your management must allow the time necessary to learn and use the system to its full potential or it won’t give any returns.
If an organization does not have clear goals for their use of simulation, their experience with the products will be mixed. Having clear goals before purchase ensures that the effort required is not misdirected.
The process simulator is worth it’s investment especially when you hire many new operators and your experience begins walking out the door either through retirements or new jobs. It is also very useful in training new engineers. They must learn the process dynamics and not just understand the process flow diagram. There is a huge learning requirement when you consider the process dynamics and not just steady-state conditions, especially for reactive chemical processes.
Like many tools, simulation software can provide a major benefit if you do your research going into the project. Otherwise, garbage in, garbage out. With clear goals, appropriate resources, and buy-in from all involved, it can provide major advantages in the right process contexts.
Peter Welander is process industries editor. Reach him at PWelander@cfemedia.com .