Analyse und Identifikation von Einsparungspotenzialen eines thermochemischen Prozesses zur Aufbereitung von Sekundärrohstoffen

As part of the Green Deal Industrial Plan, technological retrofits and innovations are to be promoted to motivate companies and industries to invest in environmentally friendly technologies and implement low-emission production methods. The aim of this study is to identify and quantify the CO2 and cost saving potential of an innovative decentralized treatment process. An essential component is the identification of suitable industrial plants with high waste heat potential and suitable temperature levels. The conversion from centralized to decentralized treatment is also intended to reduce transport costs and evaluate both ecological and economic aspects. Another focus is on the analysis of the economic profitability of the treatment plant, considering optimized operating models.
The theoretical waste heat potential of the various industrial sectors is calculated based on energy consumption and the use of individual energy sources in European and Austrian industry. The proportion of energy consumption that can be classified as chargeable waste heat losses is determined and assigned to a specific temperature level. Only variable parameters are considered in the assessment of energy and CO2 savings potential through the change of energy source. This means that the primary energy expenditure and emission loads of the source materials are generally assumed to be constant. The change of energy source refers to the transition from a pure natural gas operation to a hybrid operation in which waste heat, pyrolysis gas and natural gas or electricity are combined. The ecological and economic evaluation of the transport routes is carried out in a comprehensible manner using the visualized routes on a map. The current baseline scenario is compared with an optimized scenario to analyse the extent to which improvements in terms of environmental impact and costs can be achieved through adjustments to the transport process. The techno-economic analysis compares the treatment sites based on a defined cost structure and is evaluated by applying statistical investment ratios. The potential cost savings of the energy source change on energy costs, operating costs and total costs are examined.
Based on the analysis of the waste heat potential, the non-metallic materials industry, along with the non-ferrous metallurgy industry, has the greatest waste heat potential for temperatures above 100 °C in Austria. By implementing optimization measures in the transport process, which is converted from centralized to decentralized processing, 75 % of energy consumption and the associated emissions can be saved in the transport of coffee capsules and 50 % in the transport of printed circuit boards. At the same time, the changeover leads to a 75 % reduction in transportation costs for coffee capsule transport and a 47 % reduction for printed circuit board transport. By using industrial waste heat and self-generated pyrolysis gas in combination with natural gas, CO₂ emissions can be significantly reduced by 62 % across all sites. If electricity is used instead of natural gas to provide energy or is integrated into the process, this leads to a further reduction in emissions by a total of 74 %. The optimization of the energy supply through the partial substitution of natural gas with waste heat and pyrolysis gas leads to an improvement in the economic efficiency of the processing plants. The analysis of the results shows that although the integration of electricity into the process has a positive impact on the ecological balance, in an economic context it offers less potential for savings than the implementation of waste heat, pyrolysis gas and natural gas.