|Sharper blending through faster response: great added value with advanced on-line elemental analysis
|On-Line Chromatography and Spectroscopy
|Dr Michel Zoontjes
|Mr Michel Choua
Mr Taco van der Maten
Abstract Information :
Worldwide environmental regulations drive a constant decrease of the sulphur levels in fuels as it relates to acid rain and other detrimental environmental effects. The source for fuel, crude oil can contain high sulphur concentrations up to several percents. However regulations, like the Euro VI, US Tier 3, China 5, 6 or other equivalent regulations, set the allowed limit for sulphur content of road fuel at 10 mg/kg. The need to comply consistently with the global fuel regulations for sulphur content, leaves no room for process inefficiencies to maximize the crack-spreads. If the sulphur content in fuels can be blended and produced closer and more consistently to the regulated limits, car engines operate in a more environmental friendly way and refining operations can achieve a higher return on their production process investments. Easily thousands of Euro's per day can be saved by more accurate blending. To achieve these savings, it is essential that the fuel composition can be monitored fast and accurately in real time.
Latest advances in energy dispersive X-ray fluorescence (EDXRF) technology offers the possibility to apply XRF for on-line elemental analysis of sulfur and many other elements, simultaneously, repeatedly and at the required low concentration levels. In our presentation we discuss an on-line EDXRF analyzer for accurate blending control in refineries and fuel blending facilities. EDXRF has the advantage that multiple elements can be measured simultaneously over a wide concentration range of wt% down to a few mg/kg, for elements between sodium (Na) and americium (Am) in the periodic table. The obtained precision and accuracy allows for much tighter process control in processes like blending and feed control. Further, by employing this new on-line multi-element analyzer in other refinery processes (desalination, hydro treatment), the simultaneously monitoring of other elements like Cl, Ca, Ni, V, Fe will help to optimize process conditions and usage of catalyst and other resources. Examples will be presented of great added value blending using simultaneous multi-element analysis at low mg/kg-levels with highly repeatability.