Petroleum Institute Mexico Uses SIMDIS Technology to Accurately Determine TBP Physical Distillation

Importance of the Topic

True boiling point (TBP) distillation provides critical data for characterizing crude oil and optimizing refining processes. However, conventional TBP methods require extensive time (minimum eight hours) and sample volumes. Simulated distillation (SIMDIS) via gas chromatography can replicate TBP curves faster and with less sample, enabling rapid decision-making in research and industrial environments.

Objectives and Study Overview

The Petroleum Institute of Mexico aimed to assess the accuracy and efficiency of GC-SIMDIS technology for determining TBP distillation profiles of heavy crude oils before and after upgrading. The study compared results from PAC’s AC Analytical Controls GC with SIMDIS software against standard physical distillation methods (ASTM D2892-13 and ASTM D5236-13) and GC-SIMDIS reference method ASTM D7169.

Methodology and Instrumentation

An experimental pilot test was conducted on heavy crude oil samples from two production fields (Ku Maloob Zaap and Altamira). Each sample was analyzed in its original form and after an upgrade process. The analytical protocol included:

• Physical TBP distillation using ASTM D2892-13 and ASTM D5236-13 standards
• GC-SIMDIS analysis following ASTM D7169 simulated distillation

Key performance metrics included boiling point distribution, distillate yields by fraction, analysis time, and sample volume requirements.

Instrumentation Used

The following equipment and software were employed:

• PAC AC Analytical Controls gas chromatograph equipped with SIMDIS software
• SICA (PAC’s local representative) provided installation, training, and maintenance support

Main Results and Discussion

SIMDIS chromatographic profiles for heavy and upgraded crude oils from both fields showed tight correlation with true TBP distillation data. Key observations included:

• Analysis time reduced to under one hour versus at least eight hours for physical distillation
• Smaller sample consumption while achieving reproducible boiling point curves within method precision limits
• Comparable distillate yield distributions by fraction (naphtha, kerosene, light gas oil, vacuum gas oils, residue) between SIMDIS and TBP methods

For instance, the upgraded Altamira crude displayed naphtha yields of 14.2% (SIMDIS) and 16.8% (TBP), with overall yields below 538 °C of 66.4% (SIMDIS) and 65.9% (TBP).

Benefits and Practical Applications

Adoption of GC-SIMDIS technology offers several advantages for refinery research and quality control:

• Rapid turnaround facilitates real-time process optimization
• Lower sample volume requirements reduce material costs
• High correlation with standard TBP distillation ensures data reliability
• Enhanced laboratory throughput supports increased sample loads

Future Trends and Potential Applications

Advancements in SIMDIS could include integration with online process analyzers, coupling with advanced chemometric models for predictive maintenance, and extension to alternative feedstocks such as bio-oils and bitumen fractions. Ongoing software improvements may further refine boiling point predictions and automate data interpretation.

Conclusion

The study demonstrated that PAC’s GC-SIMDIS technology reliably reproduces true boiling point distillation data for heavy crude oils, offering significant time and sample savings. This makes it a valuable tool for refinery research, process optimization, and quality control operations.