By the early 1990s, an initial disaster cycle for refuse-derived fuels (RDF) was effectively closed and the term ended up denoting a low-quality fuel or absence of quality checks [3]. RDFs could not create sufficient demand because of the high concentrations of chlorine and heavy metals in it. The non- homogeneous distribution of elements like chlorine, cadmium and mercury in waste components leads to varying fuel qualities [16] and [17]. As chloride salts they have significant influence on corrosiveness of deposits on the superheater tubes. From an emission perspective. SRFs can be considered ''clean'' fuels. if their content of heavy metals is below certain levels. Therefore. as a general rule heavy metals concentrations need to be kept as ]0v as possible [18]. Zinc, lead and tin lower the melting temperature of deposits on the superheater tubes amplifying corrosion [19]. Trace elements that can be volatized in the combustion processes. with insufficient additional flue gas cleaning they can be released as gaseous emissions.