The great availability of industrial wastes in Europe triggered off this research project in order to examine their potential utilization as combustibles. Until recently, every European country had its own laws concerning environmental standards for incineration plants, making European collaboration on the thermal utilization of industrial wastes extremely difficult. Now, as a European law is underway, a group of researchers investigated and developed data and technologies for commercial use of wastes, especially plastics and textile wastes.In the textile waste market results showed that as the amount of this kind of waste is rather limited it can only be used for local application in grit firing in some regions of Europe. However, this material can be used in combination with biomass, improving the combustion behavior of boilers. Researchers studied the environmental impact of the combustion of many fuel blends containing waste plastics and conventional combustibles like coal and lignite etc.The alkali evaporation occurring during the combustion created serious problems in the operation of the power plant. Corrosion of metallic components, fouling or plugging of pipes and valves were the most important problems created by the presence of alkali vapor. In order to measure alkali levels in hot gas, as well as heavy metal concentration, a conventional method was used. However, the results were not satisfying, as the sensitivity of the analyzing method was low, leading to errors of unknown magnitude. In order to solve this problem, three different on-line alkali measuring devices were developed and these instruments may soon be ready for commercial use in industry. These analytical devices could be used in advanced power generation technologies, as well as conventional and biomass boilers or incineration plants.