Slagging and fouling is a major problem in biomass heat and power plants (BMHP plants), especially when plant-based biofuels are used. In order to reduce slagging and fouling processes mineralogical and chemical composition of slags and deposits were determined and documented in a biofuel catalog (BFC) that shows the relationship between biofuels and resulting slags and deposits. The BFC is intended to be used as a “know-how guide” for the combustion-related handling of biofuels, which aims to increase the energy efficiency of BMHP plants. In order to ensure a successful technical application of the BFC in practice, the procedure for the creation of the BFC is currently being validated in an ongoing research project. The first results suggest that the procedure for creating the biofuel catalog can be validated for waste wood and applied to various process technologies.