D. Beebe, Emerson, Baton Rouge,
Louisiana; and A. KALAFATIS, Aspen Technology, Houston, Texas
There is a new adage in process
manufacturing circles, and it resonates particularly deeply in the hydrocarbon
industry: If you do not like market factors today, just wait a month. In the
wake of the pandemic, it seems as though there is a new supply chain
disruption, market need, cost increase or labor shortage around every corner.
As frustrating as these market
swings are, savvy organizations also see their upside. The companies
maintaining the flexibility necessary to navigate new trends gain an
opportunity to secure competitive advantage by increasing market share and
improving profitability. One of the key technologies helping organizations
unlock and ensure flexibility is advanced process control (APC).
In the past, many considered APC only
feasible for large organizations with a deep bench of expert personnel. Those
well-resourced organizations could more easily commit countless hours to
integrating, configuring and maintaining the software alongside the plant’s
control system. APC seemed out of reach for plants that could not find, afford
and retain one or more staff members with an advanced degree in chemical
Today, however, the landscape has
changed. The best modern APC solutions have been designed to democratize
advanced control. Industry experts have worked much of the complex front-end
engineering design (FEED) into intuitive, highly integrated software,
maximizing the benefits of APC while minimizing the complexity, normal
operation disruptions and operational challenges associated with adding
advanced control to process manufacturing. Teams should focus on implementing advanced
control with a holistic mindset by choosing integrated solutions from end-to-end.
This enables a smoother path to meet operational efficiency and sustainability
goals to more quickly achieve corporate objectives (FIG. 1).
Modern APC. APC uses software logic to increase the speed and scope of modern
process control, helping organizations unlock the full value of their control
architecture. Leveraging advanced control systems—such as statistical modeling, analytics, model
predictive and multiple loop control—helps teams operate their systems closer to constraints to
drive tighter control and more predictable and stable operation. These
technologies help lower the variability of process parameters and product
quality, ultimately reducing human error while improving quality, increasing
throughput and reducing energy use and emissions by working in tandem with
effective operator oversight.
Complexity creates barriers. Traditional APC design, implementation and configuration took many
steps. First, teams needed to perform pre-testing, step testing and model
identification before building and commissioning the controllers. Typically, this
process took 3 mos–4 mos, and the required step testing was intrusive,
interrupting production and, in many cases, creating off-specification (off-spec)
However, even if a plant had the
time, resources and open schedule to perform the design phases, they often
lacked the required skilled personnel. Teams needed an expert with years of
domain expertise to understand the underlying calculations necessary to successfully
create the models and controller configuration. Even if they could find a
qualified model predictive control expert to fully understand control
configuration and model identification, that person would be needed for ongoing
software maintenance if the organization wanted long-term value from its
solution. Keeping such a person on staff across the lifecycle of the APC
software was a costly proposition.
Faster time to value. Today’s best-in-class APC solutions have upended the complex
system integration and configuration paradigm. Modern control systems are built
from the ground up to seamlessly connect to the most powerful and intuitive
solutions, eliminating the weeks of pre-work necessary to get the systems
Just as importantly, much of the domain
expertise necessary to build and configure advanced control solutions has been
built into today’s advanced control software. The most effective APC software
is designed to be configured and operated by process engineers, opening the
technology to more organizations and sites that did not previously have access
to skilled experts.
In today's state-of-the-art software,
embedded industrial artificial intelligence (AI) enables engineers to mine
existing historical process data, select variables and build a seed model. The
seed model generation step that used to take weeks can now be completed in a
day or two.
Once a seed model has been
developed, it is refined through calibration software. The calibration software
performs step testing in the background to tune the model to current operating
conditions. However, unlike manual calibration—which took months to close the loop, resulting in
reduced production and off-spec product—modern calibration software runs in the
background in much smaller increments while the controller stays online. Not
only does the plant continue to run just as it normally would, but the entire
process saves time, with many organizations seeing upwards of 75% faster time
Today’s APC software is also more
intuitive, with built-in tools to democratize configuration and operation. In
the past, operators and engineers often had little-to-no insight into what the APC
was doing at any given stage of operation. Today, the best solutions are built
with virtual advisors to tell an engineer or operator why the advanced control
performs a specific action and how to achieve a specific control objective. The
end user is empowered with a real-time understanding of why the system is doing
what it is doing and how to get the APC to do precisely what they desire.
Modern advanced control solutions
are built with a much wider range of users in mind. With AI capability, teams
can widen the operating region while using machine-learning (ML) algorithms to
help build and refine seed models (guided by ML).
Increasingly sustainable operation.
One of the key areas where APC delivers value is improved
sustainability. Nearly every organization is under pressure to meet new
sustainability goals. Some may simply need to improve energy use, while others
are overhauling operations to meet ambitious new net-zero goals.
Regardless of the reasons for
change, improving sustainability with traditional manual operations is
challenging. Operators typically dial a lot of conservatism into how they run
facilities, operating significantly away from constraints in each scope of
control. They do this for good reasons.
For example, consider a situation
where an operator was running right at a limit, and excess oxygen could mean
the process does not have complete combustion. Running regularly in such a
state would require operators to check the process status minute by minute—a stressful and potentially
Moreover, lean staffing is common
these days, and an operator might have five or six scopes of control. An
experienced operator can likely run one constraint closer to optimal, but each
of their five or six controllers might have multiple settings, each of which must
be optimized to drive peak performance in tandem with sustainability. No human
operator can handle 25 or 30 variables minute to minute.
However, multivariate APC software
can handle all those variables and more. In addition, the software can manage
the constant calculations necessary to compare operations against the operating
environment to ensure peak performance (FIG. 2).
APC predicts a system state ahead
of time to reduce variability. The software constantly checks the process and
performs optimization calculations, never getting tired or distracted. With
this capability, the system can run every process element very close to
constraints to maximize efficiency.
When the process is optimized,
teams see less reprocessing, leading to less waste, lower energy consumption
and lower overall emissions while simultaneously maximizing production. In
addition, operators are freed from low-value monitoring tasks to focus on
improvement and optimization across the plant to further improve performance
and sustainability (FIG.
More easily achieved corporate
objectives. Advanced control software
installed and properly configured at the unit level can do wonders for plant
productivity, but that value is only the beginning. When an organization builds
a strong advanced control foundation at each plant, unit by unit, implementing
APC-ready control systems across each unit and equipping them with modern,
user-friendly advanced control software can enable coordination across multiple
One of the benefits of a holistic,
real-time, multi-unit dynamic optimization solution is that teams no longer
need to worry that they are creating excess quality in one area but giving it
away in another.
For example, perhaps a facility is
over-cracking middle distillates. The team could solve the problem on the front
end at the crude column, putting those molecules in one bucket and not running
it through the process. Ultimately, they can convert them late in the process,
but in doing so, the team has used excess energy to process those molecules
into one grade and then, at the last minute, blend them in or crack them into
With dynamic optimization, the
operations team coordinates multiple process units and their respective APC
controllers to achieve peak performance end-to-end across the entire production
process. This type of closed-loop, real-time optimization of multiple units creates
a communication chain between each process unit, running the entire process as
a cohesive, dynamic whole. A change upstream in the process will be
communicated downstream so other units can compensate, ensuring they are ready
for the results of the change in operation (FIG. 4).
In fact, the most powerful APC
solutions offer smart tuning capabilities to capitalize on that inter-unit
cohesiveness, making it fast and easy to take advantage of market changes. As
costs update and profitability changes, operators can use smart tuning
solutions to adjust those variables in the software. Upon receiving the change—or the direction to
focus on a different core strategy, such as energy use instead of production—the software immediately
updates operations to reflect the new goals. Operations teams can be more
proactive, capturing value for the organization.
However, operational agility is
more than simply pivoting to meet a new need in the marketplace, as staying
agile means meeting other market challenges, such as staffing issues. Again,
this is an area where APC shines. Because the simplicity of modern advanced
control democratizes the technology, even when a group of experts leaves the
facility, new, less-experienced personnel can still maintain the system. Those
new engineers can much more easily sustain the system’s performance over time,
ensuring that the organization’s ability to maximize the value of its
operations is not lost.
Adapting to secure competitive
advantage. For plant personnel that have tried
APC in the past but were unable to achieve success—and for those that have never given advanced
control a try due to cost, time or staff limitations—this is the perfect time to reevaluate. New
technology has changed the game for advanced control, making it easy for a
plant to implement and maintain a holistic infrastructure.
Moreover, by putting an APC-ready
control system in place and pairing it with best-in-class technologies built to
democratize its design and use, teams can unlock the flexibility necessary to
drive more sustainable operations and secure competitive advantage. Those teams
will no longer need to wait for market factors to change; they will simply
identify them, and operations will instantly adapt. HP
ALEX KALAFATIS is the Vice President of Product Management at AspenTech. He is
responsible for the manufacturing and supply chain management product
portfolio. Dr. Kalafatis has spent most of his 25-yr career in the control and
optimization of processing industries across the refining, upstream, chemicals
and polymers industries. He strongly believes in digital transformation's value
in industrial facilities as a critical factor in achieving new levels of
operational excellence, including emissions reduction, energy efficiency and
sustainability with profitability—advanced process control, optimization and embedded AI are key
enablers for this transformation. Dr. Kalafatis earned an MS degree and PhD in
chemical engineering from the University of Toronto.
DUSTIN BEEBE is the Vice President of Performance Software for Emerson. He is
responsible for aligning the global control performance, operator performance
and simulation businesses and the strategy synergy between Emerson and
AspenTech. Before joining Emerson, Beebe served as the President of ProSys
until Emerson acquired it in 2018. He has been in the industrial automation
business since 1996. Beebe earned a BS degree in chemical engineering from the
University of Arkansas in Fayetteville, Arkansas.