Process for utilizing organic waste materials

A process for utilizing organic waste in a clinker production process that generates hot exhaust gases in which the waste materials are introduced as fuel and burnt in the clinker production process, wherein the waste materials comprise cellulose-containing, moist, organic waste materials and said waste materials are brought into contact with the hot exhaust gases of the clinker production process and dried in a drying step flowing in parallel therewith before they are introduced into the clinker production process, characterised in that the drying step is carried out in a drying reactor in which the moist waste materials are passed together with the hot exhaust gases through a series of concentrically arranged tubes, with multiple changes in flow direction about 180°, and by setting a maximum temperature of the hot exhaust gases to a maximum value of 400° C. by mixing in ambient air and/or air from the clinker production process before the drying process.