These technologies can be applied to several types of waste: from the semi-solid (e.g. thick- ened sludge from ef uent treatment plants) to liquid (e.g. domestic sewage) and gaseous (e.g. re nery gases) waste. However, the most common application by far is processing the Municipal Solid Waste (MSW) (Eurostat, 2013). The current most known WtE technology for MSW processing is incineration in a combined heat and power (CHP) plant.