Legal, economical as well as technical developments of the last ten years have not stopped at waste management, which has become a big chain with countless linkages. All this characteristics led to a constant advancement of waste management, which leads over product management up to the so called Zero Waste Concept, whereas the development potential is not exhausted for the years to come. Due to this fact, new trends also require innovative treatment procedures which will shape a future waste management. Up to now mechanical waste treatment techniques were mostly applied within the scope of preparation of non - hazardous waste and a small part only in the area of hazardous waste. Owing to its dangerousness, the majority of car workshop waste is treated currently in hazardous waste combustion systems, among other also in the hazardous waste combustion unit Simmeringer Haide in Vienna. This treatment of special waste is focussed on the elimination of risk potential. The company Saubermacher Dienstleistungs AG processes the car workshop waste in a different way that enables their utilisation in the cement industry as an alternative fuel or in conventional residual waste combustion units. Due to specific processing, large amounts of different metals can be recovered and sold to material recyclers. Hazardous waste combustion as well as mechanical processing of hazardous waste has advantages and disadvantages which were worked out within the present Master thesis. Besides, a direct comparison of both processes concerning energy balance and climate relevance serves for the assessment.