Final Thought: High Utilization Requires Close KPI Scrutiny

Leading indicators will tell you whether your reliability is sufficient for extended-run operations.

By Rene G. Gonzalez

By way of introduction, I have been writing about the energy industry value chain for the past 25 yr. My chemical-engineering background has led me to distillation, fouling, and corrosion-control assignments at several North American and Middle Eastern refineries. The common denominator among these facilities is the expanding level of process complexity, predicating closer adherence to reliability initiatives. A measure of complexity expressed in the refining industry is referred to as the Nelson Complexity Index (NCI). To achieve a high NCI reliability, professionals must work diligently to discover and close reliability gaps.

North America’s 133 refineries have the highest NCI ratings in the world, with an average 9.5 NCI (the most complex refinery in the world has an NCI of 14). In comparison, average European NCIs are in the 6.5 range. The higher the NCI rating, the more capable the facility is of efficiently monetizing crudes. More important, actual plant operational availability (utilization rate) is heavily dependent on efficiently synergizing plant-wide reliability. Since 2013, many of these bespoke refineries have been operating at an unprecedented 94% utilization rate.

However, the longer a hydrocarbon-processing facility runs at high rates without shutting down, the higher the probability of encountering an unplanned shutdown. Understanding how each plant component performs, in relation to other facilities with similar NCI ratings, often reveals opportunities for improvement.

The industry onus is on running a plant’s primary conversion units more than 4 yr. without shutting down. To mitigate maintenance costs, operations support and engineering staff perform proactive online maintenance at the unit level to avoid a unit or plant-wide failure.

Paying close attention to reliability gaps makes it possible for U.S. refineries to operate for more than 4 yr. without a shutdown.

Avoiding incidents requires a focus on measuring plant performance. Knowing what, when, and where to measure in a plant operating at high utilization and high severity (high temperatures, pressures, and/or mechanical stresses) begins with knowing what key performance indicators (KPIs) should be used at different stages of a typical 4-yr. run. This is not an easy task as the number of sensors needed to properly perform measurements in a typical 100,000-bpd (barrel/day) refinery has increased from 20,000 sensors, just 5 yr. ago, to 100,000 at the present time.

These “pervasive” sensors form the basis for performing the many adjustments and improvements required throughout a successful run cycle. Meanwhile, sharing information on KPIs and successful outcomes with other facilities helps drive reliability.

Financial results, product quality, and plant availability drive profit, so KPIs such as overall equipment effectiveness (OEE) need to be in place. However, these KPIs are lagging, or results, indicators that only provide a snapshot at a specific point in time. Further, many processes can influence KPIs. Therefore, it is important to also implement KPIs that target future performance, i.e., leading indicators. These leading indicators will ascertain if the lagging indicators will get better or worse and whether reliability is sustainable in refining and petrochemical operations that continue to grow in complexity.

Rene Gonzalez is a writer covering the entire energy industry value chain. He was a field engineer for a major oil-well service company and is a graduate of Texas A&M Univ.