Emission characteristics of different TCR Diesel fuels in comparison to diesel fuel derived from other sources

As part of the European Green Deal, the EU has set itself the binding target of achieving climate neutrality by 2050 with the European Climate Act. At the same time, the EU is currently being confronted with an unprecedented energy crisis coupled with an increasing economic pressure, caused by military conflicts and geopolitical tensions resulting in increased fossil fuel prices. However due to high energy density liquid hydro-carbons are still critical needed fuels for transportation. On the other hand Biomass wastes, like sewage sludge and paper sludge, are currently a significant challenge to environmental protection. As a result due to nitrate pollution in soil, e.g. sewage sludge is no longer permissible to distribute on agricultural fields in a growing number of areas such as parts of Italy and Germany. Therefore there is currently a growing move towards the use of sewage sludge or paper sludge in thermal conversion processes. The Fraunhofer-Institute for Environmental, Safety and Energy Technology (UMSICHT) developed the Thermo-catalytic reforming (TCR®) process has been designed to specifically convert residue and waste biomass, such as sewage sludge, paper sludge, biogas digestate, or livestock manure into a variety of energy products like char, crude bio-oil, and permanent gases. In combination with a hydrogenation process this process can be used to produce a drop-in bio-fuel with physical and chemical characteristics close to fossil diesel according to EN590. The emission characteristics of such fuels used in a production type Diesel engine with modern common rail system has up to now not been tested. In this work we demonstrate the influence of different TCR® refining diesel fuels on emission, power and efficiency in comparison to reference Diesel fuel (Homologation fuel for Euro 6 emission testing) and hydrotreated vegetable Oil (HVO). The comparison was performed at an engine test bench equipped with a Hatz 4H50 TIC direct injection common rail diesel engine. For different engine operation points exhaust gas emissions and particulate matters were measured and the results analyzed.