In order to increase the efficiency of diesel particulate filter regeneration more knowledge about diesel soot and its reactivity is required. This thesis compares soot created during accelerated filter loading by lowered rail pressure, with soot from normal filter loading. Soot properties and their correlations to oxidation reactivity are also examined through thermogravimetric analysis, scanning electron microscopy, energy dispersive x-ray spectroscopy, BET nitrogen sorption, and FTIR spectroscopy. The usefulness of these analysis methods was also evaluated. The soot samples consisted of two carbon blacks for reference (Printex U and Vulcan XC 72), four accelerated soot samples and two non-accelerated samples. The results showed that the accelerated samples contained less volatile organic compounds than the non-accelerated soot and required slightly higher temperatures to oxidize in air. Soot with a high oxygen/carbon ratio and high levels of volatile organic compounds was found to be the most reactive. The most useful method for analyzing the soot was the thermogravimetric analysis. The scanning electron microscopy and energy dispersive x-ray spectroscopy were useful additions but the FTIR spectroscopy provided very little useful information. The usefulness of BET nitrogen sorption was not decisively concluded. / För att kunna förbättra regenereringen av dieselpartikelfilter krävs en ökad kunskap om dieselsot och dess reaktivitet. I detta examensarbete jämförs sot som skapas vid accelererad sotinlagring genom sänkt railtryck, med sot från normal sotinlagring. Hur sotets egenskaper påverkar dess reaktivitet undersöks också genom termogravimetrisk analys, svepelektronmikroskopi, energidispersiv röntgenspektroskopi, BET-kväveadsorption och FTIR-spektroskopi. Hur väl dessa analysmetoder lämpar sig för analys av sot utvärderades också. Sotproverna utgjordes av två så kallade ”carbon black” för referens (Printex U och Vulcan XC 72), fyra accelererade sotprov och två icke-accelererade prov. Resultaten visade att de accelererade proverna innehöll mindre flyktiga organiska föreningar än icke-accelererade sot och krävde något högre temperaturer för att oxideras i luft. Sot med ett högt syre/kol-förhållande och höga nivåer av flyktiga organiska föreningar visade sig vara mest reaktivt. Den mest användbara metoden för att analysera sot var den termogravimetriska analysen. Svepelektronmikroskopi och energidispersiv röntgenspektroskopi var användbara som komplementerande metoder men FTIR-spektroskopi gav väldigt lite användbar information. Ingen konkret slutsats drogs gällande nyttan av BET-kväveadsorption.

This dissertation deals with a development of a laser welded common rail with a radially attached RPS sensor of pressure. The new concept required by Bosch Diesel s.r.o. Jihlava should be more modifiable and it should be easily integrated with the engine compartment. In this dissertation I suggested a number of concepts that I further analysed, verified in appropriate software, developed, and finally narrowed the selection down to the most suitable solution, which is recommended and justified in the conclusion.