Diverse Use Cases for Advanced Model-Based Process Controls Deployment Towards Long-Term Sustainable, Safer, Energy-Efficient and Profitable Operations
Authors: Kotsiopoulou G. 
Published: October 2023

Changes to regulatory frameworks and the ever-evolving industry are dictating long-term sustainable, greener, lean and optimized operations. Moreover, considering that in Upstream the production facilities are characterized by highly variable input conditions from wellsites, changing demands, process oscillations and complex process dynamics, the asset owners are facing nowadays challenges that cannot always be solved with traditional control strategies. This paper explores the diverse Use Cases of APC in our Upstream Energy Division.

An agile methodology has been followed in order to introduce and rollout the model-predictive controllers in our key production hubs. The first implementation that was concluded in 2021 has showcased the economic and strategic value case of the Advanced Process Control (APC), in addition to other qualities such as its adjustability and flexibility that were proven by performing the design and commissioning in an almost remote manner. The resulting success of the first use-cases has opened the door for additional ones, while establishing APC as a long-lasting, standard digital solution for our assets' transformation and optimization.

Prior to the APC deployment, as the nature of the process is depicted by high variability and consequent high oscillations, the application of safe margins on the top of the threshold or specification of the system to avoid spurious plant trips was required. In addition, over plants' lifetime their operating envelope of the plants might diverge from the design case leading to overspecification of their respective final products such as dewpoints (water and hydrocarbon), RVP (Reid Vapor Pressure), electric power consumption and loss of consumables. By applying the Dynamic Matrix Controller (DMC), the dependent variables such as quality specifications are maximized within the normal operating envelope and avoiding off-specs, leading to minimization/optimization of operational costs (energy savings, consumables, etc.). Furthermore, the online controllers' targets were incremental production of the most-profitable yield of the respective plant, process harmonization, enhanced plant stability and reduced CO2 emissions, in agreement with the company's 2030 climate targets and commitments. Furthermore, with DMC running autonomously manual intervention has been minimized, resulting to partial autonomy of the systems that can reject better various process disturbances.

Novel designs of the online controllers and their strategies were employed to meet key-objectives. This paper portrays the steps for applying APC solutions innovatively and remotely to obtain self-optimized, safe, fit-for-future, sustainable and energy efficient production and processing facilities overcoming global challenges. Lessons learnt covering multiple aspects, from architecture and technology, upgrading strategies, to human factors, are also described, which were gathered globally with the aim of avoiding pitfalls in future deployments.