Start Date
February 2025

Introduction
This project is an amalgamation of three legacy projects (Phosphorus in Crude Oil, Toluene Insoluble Organic Materials (TIOM), Tower Top Fouling. These three projects all involved investigation of deposits found in crude towers, heat exchangers, strainers, pump circuits as well as other locations throughout the crude value chain. These projects have been combined primarily because the analysis protocol used to characterize the deposits are the same regardless of the origin of the deposit. The same techniques are being employed including, solvent extraction, XRD, TGA, Pyrolysis-GCMS^HR, TGA-FTIR-GCMS^LR, MALDI-FTICRMS^HR, etc… It was logical to consolidate deposit characterization into one project.

Historical Background

Phosphorus in Crude
The phosphorus in crude project started in 1997 is response to crude tower tray fouling characterized by tray flooding caused by heavily fouled bubble caps, stuck valves, narrowed orifices, etc… The deposits contained a large percentage of phosphorus and were eventually linked to the use of phosphate ester gellants common in fracturing operations. Since 2017, regular updates on volatile phosphorus testing, carried out by Pembina Pipelines, have been provided at project meetings with Pembina providing terminal data for over two decades. No volatile phosphorus above the 1.5 wppm limit had been detected during the regular testing of ~2400 samples during 2018 and 2019 and as a result, in 2020, Pembina scaled back testing. They are still testing delivery points at some key nodes along the mainline. The CCQTA recent saw deposits with similar levels of phosphorus however these new deposits present with different morphology than those in the past. Previous deposits were hard and adherent while more recent deposits are powdering and easily removed.

Toluene Insoluble Material
This project built on previous work in the NGL Fractionation, Iron Fouling, Oil Sands Bitumen Processibility, and Condensate Quality projects to investigate the nature and origin of Toluene Insoluble Organic Material (TIOM) deposits. TIOMs are problematic black deposits found throughout the industry, notable for their insolubility in conventional solvents and often absence of functional groups. Through extensive sampling and analysis, the project has developed a detailed protocol for TIOM identification and is evaluating several potential sources, including polymers, naturally occurring kerogen, and interactions between asphaltenes and mineral clays. Ongoing work focuses on understanding formation mechanisms and identifying mitigation strategies to minimize fouling and operational impacts across the industry.

Tower Top Fouling
This project addresses fouling issues in crude unit tower overheads and pump-around circuits by investigating common mechanisms and source materials across multiple refineries. Initial work has involved characterizing deposits collected from several sites. Ongoing analysis of additional samples continues to refine the understanding of fouling mechanisms, with the goal of improving identification methods and informing mitigation strategies.

Recent Updates

• Comparative analysis by pyrolysis-GCMS is underway on samples from two different refineries.
  
• Refinery heat exchanger deposits are currently being characterized.