Biogasclean QSR and OS are constructed with the QSR® – Quick Sludge Removal – system. During QSR® cleaning the tank is filled with water and pressurized air is injected in the bottom of the tank so the packing media is washed like in a big washing machine. The QSR® system makes it possible to clean the tank for sulfur and gypsum sludge without emptying the tank for packing media. Also the packing media in Biogasclean ECO can be cleaned inside the tank. This will reduce downtime and increase revenues.