Method for refinery foulant deposit characterization

An analytical protocol to identify a refinery solid foulant of unknown composition caused by scaling, corrosion, precipitation, chemical reaction, or particulate fouling comprising

• a) obtaining a homogeneous foulant sample which is subjected to a series of tests and evaluations to identify the foulant,
• b) removing rapped feed from said sample with a solvent to remove any soluble sample and to obtain an insoluble sample,
• c) scanning said insoluble sample with scanning electron microscopy,
• X-ray Diffraction and energy dispersive x-rays to qualitatively identify the elements present,
• d) grinding and mixing said insoluble sample to obtain a homogeneous insoluble sample;
• e) performing a thermal gravimetric analysis including an ash test on the homogeneous insoluble sample to determine the presence of organic polymer, coke and inorganic elements, and if said homogenous insoluble sample contains about 10-15% or greater inorganics, go to step f), and if not, go to step g),
• f) performing an elemental analysis on the homogeneous insoluble sample to determine the elements carbon, hydrogen, sulfur, nitrogen, halogens, and metals, and hydrocarbon to carbon ratio to correlate with temperature of deposition,
• g) performing an optical microscopy on the homogeneous insoluble sample to determine the presence of wax, asphaltenes, anisotropic coke and isotropic coke, and
• h) relating the composition, amounts and characteristics of both the inorganics and organic determined in the steps above to determine the cause and identity of the composition of the solid refinery foulant.