Tick-tock feedstock

The dynamics of the global refining and petrochemical market have changed in recent years. The world’s crude sources and refining capacity continue to expand and shift geographically. Refinery closures and divestitures in some geographies create opportunities for nimble organisations. Being able to easily evaluate and model the effects of crude feedstock selections and getting the right crude oil to the right refinery is vital to turning those opportunities into profits. With competition increasing, time is ticking for many refineries to protect margins and examine their processes, including feedstock selection, to extract every bit of profit possible from their operations. 

The implementation of leading-edge software makes accurate and rigorous petroleum refining simulation accessible to more refining organisations with clear and simpler visualisation tools to understand model results. This helps industry leaders to make complex business decisions for the best possible use of their production operations and to more accurately forecast and understand the results. Isolated worlds of refinery engineers, planners, schedulers and traders, can now be closely tied together to achieve a level of collaboration with improved ability to optimise the entire refinery operation. Planning and scheduling models can be kept up-to-date and more accurate through simple and immediate access to results of engineering models tuned with current operating results, increasing the confidence that plans will more closely mirror actual production performance. This makes operational decisions more straightforward. Overall, integrated process engineering software provides faster, more accurate and frequent analysis to achieve refinery profitability.

Moving from estimation to analysis and accuracy

A crude oil assay, the laboratory profile of candidate crude properties, is the unique fingerprint and fundamental basis for understanding how a crude feedstock will perform in a refinery configuration. Assay data helps refinery engineers and planners determine particular crudes (or more typical mix of crudes), whether that oil feedstock is compatible with a particular petroleum refinery train or whether the new candidate crude itself might trigger issues reducing yield and quality or restricting product mix flexibility.

Refiners continually seek to speed up and improve feedstock purchase decision-making ability through new techniques and technology to analyse their options rapidly when giving instructions to traders. While finished product demand is weak in some regions, crude costs remain high, putting downward pressure on margins. As crude production declines in established producing areas, refiners are now forced to consider new sources to replace existing declining sources. Over time, most refiners must broaden their crude slates to lower average acquisition costs. 

Automating assay management adds value

There are several key trends in application and use of software modelling tools in this new environment.  First, rigorous engineering simulation models have become extremely important in understanding how to best operate a refining or petrochemical facility. Companies are increasingly employing engineering models, calibrated against current plant conditions, for tuning, decision-making, evaluating feedstock and product options. At the same time, planning software is increasingly used to evaluate both crudes and petrochemical feedstocks faster. With these modelling tools, leading-edge producers are taking advantage of engineering models to more accurately and frequently update planning models and increase planning validity and accuracy. Models are dependent on the accuracy of the hydrocarbon characterisations, so companies need powerful process engineering tools, which can characterise crudes, analyse multiple feedstocks, track petroleum properties and carbon emissions and leverage activated energy and economics for maximised profits. Advances in the ability to accurate characterise crudes from limited assay data is a key area of software innovation.

With today’s software, it is easy to update refinery planning and scheduling. Aspen HYSYS^® Petroleum Refining includes tools to import and export petroleum assays to and from Aspen PIMS with the new Aspen Assay Management. Aspen HYSYS Petroleum Refining layers powerful features into the Aspen HYSYS process simulator to improve petroleum refining simulations. Streams are driven with crude assays that support an extensive set of stream petroleum properties. Multi-unit simulations can be quickly configured incorporating key conversion units, such as FCC and associated fractionation. By automating the import of crude data from Aspen Assay Management into Aspen HYSYS Petroleum Refining, users eliminate the manual process of entering hundreds of crude data points in order to accurately model a crude slate.

Key benefits of using process engineering software tools:

• Better and faster crude feedstock selection through joint use of planning and engineering models.
• Improved operations through more accurate scheduling models.
• More powerful operability studies, based on accurately calibrated engineering models, to confirm the feasibility, safety and reliability of potential crude blends.
• Improved unit profitability through engineering studies that reduce energy use and regulated emissions.
• Improved refinery margins through re-evaluation of feed routings in multi-unit configurations.

Many companies see benefits from the adoption of process modelling software. Companies can increase profits with better feedstock selection, using consistent assay data across tools such as Aspen HYSYS and Aspen PIMS. Also, they can optimise the process for heavy crude handling, whereby the assay characterisation is now better for heavier, more complex crudes. For example, Saudi Aramco E&P increased throughput by 3 - 8%, reduced planning time by 50 - 70%, reduced inventory by 15 - 35% and made 3 - 5% energy savings by integrating Aspen HYSYS and Aspen PIMS across all major surface facilities.

Time to drive profitability

Feedstock assay data are an important tool in the refining process. The clock is ticking regarding the attractiveness of certain feedstocks. Liquid feedstocks will be dependent on future oil prices and other routes to petrochemicals will be subject to scrutiny and assessed according to their technical and environmental safety and feasibility. Times are changing as shifting feedstock slate creates challenges and opportunities for the industry. Companies are faced with increased global economic challenges, dynamic market conditions and pressure to reduce time-to-market. By implementing cutting edge software, refining and petrochemicals companies will improve feedstock selection, so users can integrate crude assay libraries and links to LP planning tools for better crude selection, planning and scheduling of operations - all in an effort to maximise plant performance and business profitability. The enlightened organisation will be able to use these tools to make faster decisions, take advantage of both purchase and sale opportunities, reduce economic uncertainty and gain a competitive advantage.

Written by Ron Beck, Director for Engineering, AspenTech, and Caleigh Holden and Vince Ye, Product Managers, Refining, AspenTech.

Edited by Callum O'Reilly

Read the article online at: https://www.worldpipelines.com/special-reports/16052014/tick-tock_feedstock_038/