Tuesday, March 1, 2016

Optimizing your Process with Advanced Process Control: APC on an 60,000 BPD refinery can increase profitability by $875K!



Joseph McMullen
Director SimSci Marketing

Advanced Process Control (APC) software has been successfully implemented in the refining, petrochemical, chemical, & other industries for years. APC uses rigorous and robust calculations, process modeling, and controller design to provide robust control and optimization for your operations. The purpose of APC software is to minimize the typical process fluctuations resulting from normal controller operation. Reducing the fluctuations allows for the controller set points to be set much closer to the operating limit with minimal danger of exceeding that limit. This business value is illustrated in Figure 1 below.

Figure 1. Illustration of how reduces process fluctuations result in operating closer to the operational limits.

In refining, APC has been a useful tool that has allowed engineers to improve their control over the process for many years. For example, at a 60,000 BPD refinery in the middle of the United States that produces naphtha, kerosene, diesel, AGO/LVGO, and HVGO the operators had difficulty in keeping
the unit stable with products on spec due to crude switches, and especially addition of various slop oils as charge every few days. So in May of 2015 they commissioned APC from Schneider Electric in less than 2 weeks. The commissioning went smoothly and the APC ran constantly for about 5 months, even during turnaround at low rates, with no issues. In the end implementation of the APC was highly accepted by operators and resulted in yield improvements that increased profitability by $875,000/year. The payback period on APC software is less than a year so more operating companies should be implementing it.

The main problem in implementing APC software has been the learning curve required to adequately develop and maintain an APC model. However recent advances in APC software, like SimSci APC, have significantly reduced that learning curve by improving the user interface to match the quality interface that people expect today. When combined with an intuitive workflow, APC software is not only powerful, value generating software, but it is now easier to use than ever with an improved interface, enhanced trending, advanced controller functionality and innovative customization.

Modern, Intuitive Interface and Streamlined Workflow
The new user interface of SimSci APC has a familiar Microsoft look and feel and is very easy to navigate (Figure 2). The workflow in this re-designed user interface was engineered to be easy to follow, allowing the user to follow the natural workflow of an APC project, from connecting to data, designing process test, identifying the model, and building the controller all the way to commissioning the designed controller, with little need for the instruction manual.

Figure 2. Example of the clutter free and simple SimSci APC user interface

Powerful Trending
Most engineers crave data. SimSci APC provides the control engineer with data in the form of trends that can easily be created, managed, compared and manipulated for analysis. Each trend display can be individually customized (Figure 3). The trends are all synchronized automatically. Past, current, and predicted future values for process variables can be plotted together with past, current, and future moves for a controller to evaluate the performance of the controller.

Figure 3. Example of the trending interface within SimSci APC

Advanced Functionalities
SimSci APC also has multi-controller and subcontroller functionality. The multi-controller functionality allows SimSci APC to design, commission, and manage multiple APC controllers within a single APC server (Figure 4). The subcontroller functionality allows SimSci APC easily turn on and off segments of a controller. Model migration is another key feature. Most engineers are not interested in rebuilding models that they have already created so SimSci APC allows the user to easily migrate models and controllers from Connoisseur, as well as from competitor APC software.

Figure 4. Example of the subcontroller interface within SimSci APC

Easy to Learn, Yet Powerful Director Code
Perhaps the most important feature of any APC software is customization. An engineer needs to be able to adapt their model to accurately model the plant. Director provides re-useable, customizable user defined functions to augment the controller capabilities or add custom supporting functions to cope with changing process conditions or states. The result is that SimSci APC is able to achieve a higher service factor when compared to traditional APC applications that don’t enjoy the flexibility and benefit of Director.

The Future of Advanced Process Control is Here
Similar to our example above, if APC on an 60,000 BPD refinery can increase profitability by $875K, why aren’t you considering it? Technology has lowered the barrier to implementing APC  You can now get the same value that you could have gotten from previous iterations of APC software that are more intuitive and much easier to use. SimSci  APC was engineered to provide quality advanced process control with a powerfully simple user experience. What are you waiting for? software.schneider-electric.com\apc