Refinery Operations Logo

Automation’s Role at the Front End of the Refinery

Refineries are looking for ways to improve profits through better utilization of current assets and deference of major expenditures. However, refinery utilization rates for many refiners have improved significantly along with margins, predicating a higher level of automation and control investment.

It is probably not feasible to expect to continue seeing refiners cutting costs at the same level as before 2010. Nonetheless, decreasing “cost structures” in the downstream refining business mandate hard economic justification for major expenditures and new investments, including new automation systems.

Wherever possible, marginal projects and plant upgrades have been shelved while still trying to sustain efforts to improve efficiency and reliability. At some point beyond 2017, the industry may reach a plateau in efficiency improvements. Thereafter, new automation systems will be necessary for supporting optimization strategies such as predictive asset management.

CDU severity.

CDU severity.

At the same time, enabling technology will also be needed in support of low carbon technologies —-  a new challenge for even the most experienced professionals. In other areas, the major automation suppliers are providing effective partnerships with operating companies and technology licensors. In many cases, the automation experts pursue a parallel track with the technology supplier/licensor and the refinery to implement control systems in key conversion units, such as with reducing the variability in hydrogen purity from pressure swing adsorption (PSA) applied to refinery offgas. This has become just one of the many important tasks targeted for improvement by most refiners, as they increase hydroprocessing capacity and severity.

Refiners expecting stable margins and utilization rates between now and 2017 know that they only have a short window to implement the technology needed to turn a profit. In many cases, the basis for making a profit over the next two or three years means avoiding unplanned shutdowns, safe operations and higher throughputs. One of the most efficient ways of achieving these goals is by improving automation and control of existing assets.

To be sure, it would be nice to have the capital to build a new crude/vacuum unit with upgraded metallurgy, the latest in fired heater design, additional desalting capacity and all the other metrics needed to process the heaviest and most hydrogen-deficient crudes on the market as well as the lightest and most sulfur free crudes on the market, but the reality is that much of the capital outlays planned over the next two years has already been committed to improving the refinery to midstream interface, followed by revamping downstream conversion units, such as the FCCU, hydrocracker, etc.

There are compelling arguments for justifying higher-than-planned investment in upgrading crude units for a variety of reasons, such as increasing diesel production directly from the vacuum unit, increasing atmospheric gas oil production to FCC and/or hydrocracking operations. However, it’s no secret that the refining industry is neoconservative about “experimenting” with new types of technology, such as application of multi-variable predictive (MPC) control, well proven in linear processes, to non-linear processes such as crude unit “switching” operations.

Optimal crude unit switching operations are becoming a “do it right the first time” priority as more refiners are documenting the introduction of feedstocks that they have not traditionally processed in the past. Refiners have no doubt found ways to improve crude unit flexibility, perhaps without the level of investment needed to upgrade downstream thermal conversion and catalytic conversion units. In any case, there was probably an automation aspect to the upgrade.

Leave a Reply

Posted by: Rene Gonzalez

Rene G Gonzalez is the Director for RefineryOperations.com and contributing editor for DownstreamBusiness.com. As a chemical engineer (Texas A&M University: 1982), Gonzalez has worked in various engineering capacities throughout the energy industry value chain, primarily in refinery processing and operations.

Refinery Operations