The simulation process in Aspen HYSYS facilitates engineers in mapping key units (from Crude Distillation Unit (CDU) to Natural Gas Liquids (NGL) fractionation) before changes are made in the field. AspenTech integrates distillation columns, hydraulic analysis, and dynamic studies into a single working environment, allowing for faster troubleshooting and efficiency improvements.
In the refinery, the CDU separates light-heavy fractions at near-atmospheric pressure to produce naphtha, kerosene, diesel, and residues; the residues are then sent to the VDU. Understanding the temperature/pressure profile and reflux loops is crucial when preparing the base model. HYSYS helps visualize column performance (trays/packing) and observe the effects of load changes on operations.
In the midstream, the NGL fractionation train typically starts with a demethanizer, followed by a deethanizer, depropanizer, and debutanizer to produce market-purity products. This sequence is driven by differences in boiling points and is often operated under cryogenic conditions at the front end. Industry and academic literature emphasize the column sequence and control/efficiency strategies, which are useful when preparing scenario studies and optimization tests.
Finally, the column analysis feature and optimization studies within the HYSYS ecosystem shorten “what-if” iterations, from checking hydraulic bottlenecks to finding the most profitable operating set points.
References:
- AspenTech – Aspen HYSYS product page: https://www.aspentech.com/en/products/engineering/aspen-hysys
- AspenTech – Column Analysis webinar (HYSYS & Aspen Plus V9): https://www.aspentech.com/en/resources/on-demand-webinars/optimize-column-performance-with-column-analysis-in-aspen-hysys-and-aspen-plus-v9
- Penn State (FSC 432) – Atmospheric & Vacuum Distillation Units: https://courses.ems.psu.edu/fsc432/content/atmospheric-and-vacuum-distillation-units
- Wikipedia – Atmospheric distillation of crude oil (CDU summary): https://en.wikipedia.org/wiki/Atmospheric_distillation_of_crude_oil
- Univ. of Michigan – Hydrocarbon Recovery (NGL train summary): https://encyclopedia.che.engin.umich.edu/hydrocarbon-recovery/
- Penn State (FSC 432) – Natural Gas Processing (deethanizer–depropanizer–debutanizer sequence): https://courses.ems.psu.edu/fsc432/content/natural-gas-processing
- Emerson (NGL plant applications & column sequence): https://www.emerson.com/documents/automation/application-note-improving-natural-gas-liquids-plant-performance-process-gas-chromatographs-rosemount-en-71786.pdf
- AspenTech – Optimization & custom equipment overview: https://www.aspentech.com/en/applications/engineering/optimization-with-custom-equipment