Analysis and Optimization of H2S Scavenger Systems Using X-Ray Fluorescence Spectroscopy

摘要

Field methods are available for the determination of dithiazine content in spent hydrogen sulfide scavengers. While these methods are useful, accuracy of the assay and interference from other chemical species or matrix effects can limit the utility of these methodologies. Due to the limitations of these methods, alternate analytical techniques were investigated. An analytical method has been developed using x-ray fluorescent (XRF) techniques that rapidly provides accurate results for total sulfur content in these scavengers. The method uses analytical equipment commercially available for sulfur in oil analysis. Sulfur compound speciation is not possible with XRF techniques, however speciation is not a critical factor in optimization as the goal is to maximize sulfur uptake while limiting dithiazine content and available sulfur to form dithiazine. The method finds application in any other scavenger solutions where soluble sulfur species are present, for example, alkanolamines or solvent based such as polyethylene glycol methyl esters. Instrument calibration is dependent upon the matrix being analyzed; however the method is robust within similar matrices of material. Instruments used for this application are light, portable and easy to use in a laboratory environment or a field environment. The method has been applied in a variety of locations in the United States and Canada to aid in optimization of scavenger application. Verification of the accuracy of the method was confirmed by random sampling and combustion analysis of the random sample of spent scavenger at Alberta Sulphur Research.