EMISSION AND PERFORMANCE POTENTIAL OFSULPHURFREE FUELS

摘要

In order to meet future European air quality targets, the EU Commission has enforced avariety of measures affecting automotive and oil industry as well. Both industries are presently engagedin the development of adequate solutions.One of the main challenge for the oil industry results from the new target of sulphur content in fuelswhereas development and implementation of aftertreatment technologies plays a key role for theautomotive industry. In the course of most recent developments - especially on catalysts with Noxstorage ability - the car industry demands fuel sulphur contents much lower that layed down in the EUCommission’s Fuel Directive for 2000 and 2005, respectively.In reaction to these demands a program was initiated aimed at the exploration of available technics toproduce ?sulphurfree“ Diesel fuels. For this purpose hydrogenation pilot plant operated at the VEBAOEL R&D-department were used for experiments with conventional middle distillate feedstocks aspresently utilized in diesel fuel production. The required degree of desulfurization was achieved byincreases of the reactor temperatures as well as via prolongation of reaction time.The processed components were used to blend two ?sulphurfree (< 10ppm)“ and two ?low sulphur(< 50 ppm)“ Diesel fuels in accordance with the EN 590 standard as in charge from January 2000.Analysis of feedstocks and fuels covered their chemical composition and typical fuel parameters suchas density, boiling range, viscosity, cloud point, CFPP, Cetane Number and Index, lubricity etc.The so derived fuels were used for exhaust emission measurements of regulated pollutants with aconventional Diesel passenger car on a chassis dynamometer. It was equipped with a 4-cylinder enginewith 1600 cm3 displacement and prechamber injection. Samples of market Diesel fuel as well as CityDiesel fuel were also tested for reasons of comparison.Emission test results (CO, HC, Nox and PM) have been correlated versus sulphur and polyaromaticcontent of the fuels. The influence of both fuel parameters on the emission level was found to berelatively small for the investigated vehicle/engine system.