Asphaltenes
Asphaltenes are a natural constituent of many crude oils and may be precipitated in production systems when the crude’s natural solvency for them is reduced. Several factors including, pressure, temperature, and composition can change the stability of these high molecular weight, polar molecules allowing them to flocculate.
Asphaltene deposition
Asphaltene deposition can be observed during normal operations at pressures above the bubble point. Alternatively, operations such as miscible gas injection or artificial lift can increase the risk of deposition.
KAT offers both the ASTM D4740 Spot Test and the Microscopy Titration technique initially developed by New Mexico Tech and Chevron as simple tools to assess the kinetics of asphaltene deposition in “dead” fluids and screen for potential asphaltene instability.
Asphaltene Dispersency Tests [ADT] are then used to evaluate the performances of candidate inhibitors and dispersants.
How it works
In the KAT dispersency test, asphaltenes in “dead” fluids are destabilised by addition of an alkane solvent at ambient pressure. Flocculated asphaltenes then sink towards the bottom of a graduated tube and form a sediment. The sedimented volume is the test measurement. Additives may inhibit flocculation or, more usually, retain the floccs in suspension [dispersion].
Asphaltene Onset Pressure determination
In conjunction with our partners, KAT can offer Asphaltene Onset Pressure determination using pressurised, bottomhole field samples. Alternatively, we can also offer ASphaltne InStability Trend [ASIST] modelling which estimates asphaltene instability in produced oil at various pressures and temperatures based on small volume, stock tank fluid measurements.
Fluid Analysis
KAT offers a suite of analyses to characterise crude oil and gas condensate samples and help assess the potential impact on production operations.SARA [latroscan]Separates the test fluid into four solubility classes: Saturate (Paraffin), Aromatic, Resin, and Asphaltenes using the Iatroscan…
Asphaltenes
Asphaltenes are a natural constituent of many crude oils and may be precipitated in production systems when the crude’s natural solvency for them is reduced. Several factors including, pressure, temperature, and composition can change the stability of these high molecular…
Separation
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Rheology
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Arn Acids
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T-SEP®
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