Along with black coal, natural gas and nuclear power, one of the most important sources of energy is brown coal. Every year, about 180 million tons are open-cast mined in Germany and used in coal-fired power stations to produce electricity. One method used to clean the flue gas produced during coal firing in an environmentally compatible way is the flue gas desulphurization plant (FGDP). A by-product of this process is the FGDP gypsum resulting from gypsum slurries. Filter belts made by GKD – Gebr. Kufferath AG facilitate efficient dewatering of FGDP gypsum on vacuum belt filter plants and thus play a key role in the further processing of FGDP gypsum in the building materials industry.