Volume 2, Issue 8 (September 2005)
Determination of Sulfur Content in Crude Oil Using On-Line X-ray Transmission Technology
This paper describes the function and use of X-ray Transmission (XRT) analytical instrumentation as applied to the classification and blending of crude oil that contains 0.1–3.3% sulfur by weight. In the XRT method, sulfur absorbs X-rays transmitted between an X-ray source and detector. The technique compensates for density changes in the oil and minimizes the effects of variations in the C/H ratio of the oil. When used on-line the instrument obtains the sulfur measurement in the high-pressure flow conditions required to pump crude oil, typically 800 psig in pipelines. Automatic compensation for variations in oil density and temperature are achieved using integrated densitometer and temperature sensor readings taken by the instrument as the sulfur is being measured. In this paper calibration, precision, and long-term stability results are shown. Experimental data were obtained using a commercially available on-line XRT analyzer.