The invention relates to a process for treating a hydrocarbonaceous waste material, in particular a rolling scale slurry and/or grinding slurry, the waste material being heated in a dryer, preferably moving, by the indirect supply of heat, and in the process hydrocarbons, if appropriate together with other volatile components, in particular H2O, being removed. In this process, in the dryer, at low temperature, the hydrocarbons are broken down in a specific way, the hydrocarbons being broken down by chemical and/or radiation means, which effect decomposition of the hydrocarbons of low volatility into highly volatile hydrocarbons, preferably decomposing high molecular weight hydrocarbons into lower molecular weight hydrocarbons, and the hydrocarbons, if appropriate together with the other volatile components in particular together with the H2O, are at least partially discharged, in particular by suction, from the vessel. The invention also relates to a apparatus for treating a hydrocarbonaceous waste material.