Resource conservation in the paper industry
Research project EnEWA
The BMWK-funded EnEWA research project increases resource efficiency in the paper industry by tapping new sources of raw materials and optimizing the preparation process.
Paper is a sustainable product based on renewable raw materials. In particular, the production of recycled paper based on recovered paper already successfully and efficiently utilizes the established recyclable material cycles and is in many respects a pioneer of the circular economy. A recycling rate of over 80% for packaging papers is clear evidence of this. Nevertheless, there is also potential for optimization in the production and recycling process of recycled paper. There is potential, for example, in the area of energy efficiency, the increased use of renewable energies, the optimization of closed water cycles and, associated with this, also in the reduction of CO2 emissions. In Germany, paper production causes annual CO2 emissions of 10.6 million metric tons, equivalent to the emissions of around 4.5 million cars. A large proportion of the raw materials and emissions required are generated in the production of virgin fiber paper and can be noticeably reduced by increasing the recovered paper return rate, which is currently 79.3% according to the Association of German Paper Producers.
In order to sustainably improve the environmental balance sheet of paper production, the EnEWA research project (energy savings in paper production by opening up the value chains of recovered paper from lightweight packaging, residual waste and commercial waste) is pursuing the approach of developing new sources for environmentally friendly recovered paper recycling and making them usable. To this end, the Institute for Anthropogenic Material Cycles (ANTS) at RWTH Aachen University and the Chair of International Production Engineering and Management (IPEM) at the University of Siegen are researching a solution together with industrial partners Tomra Sorting GmbH, STADLER Anlagenbau GmbH and PROPAKMA GmbH, as well as paper producer LEIPA Group GmbH. The central element of the research project is to investigate the potential for (re)recovering paper fibers from mixed waste streams (light packaging waste, commercial waste and residual waste) for paper production. Already today, paper-based packaging from the food industry has a significant share with an increasing trend. The possibility of recovering the fibers from this lightweight packaging would contribute to increased acceptance among producers and consumers - and thus to increased use of these packaging solutions. Ultimately, the amount of available recycled fibers can be increased through a further material flow for the benefit of the environment, people and the circular economy. In addition, the utilization of paper that is incorrectly disposed of, especially in private households - so-called misfills - is being examined in order to also process this into new recycled paper.
I n the course of this, the project participants deal with the various phases of waste paper collection, recovery and reprocessing. After an analysis of the recovered paper grades and recovered paper composites to be recovered, as well as their quality within the scope of material flow analyses, the necessary sorting technology will be developed and adapted in the second project phase.
In the project, ANTS combines applied research with a focus on material flow characterization and links primary data collection with ecological evaluation and modeling of the processes. In addition, the recyclability of the rejects is analyzed and tested. The material flow characterization in the first step not only reveals the secondary recyclable material potential, but is also essential for all further processing, sorting and recycling steps. An analysis of material flows on this scale places special demands on the statistical design and the practical implementation of sampling. The ecological assessment is carried out alongside the project and ensures that the recycling process promotes the development towards a circular economy. A scenario analysis also shows different possibilities of the recycling process and provides decisive impulses for the process modeling. The recycling of rejects is an important step to close the whole cycle in the long run.
The waste paper and paper composites obtained in the sorting process undergo both regular and special treatment processes in waste paper recycling to obtain paper fibers, which are extended in the project by additional hygienization - to avoid microbiological contamination. Finally, the paper quality will be checked by LEIPA Group GmbH to ensure that the previously high paper quality is maintained.
The responsible project engineers Alena Spies and Dr. Karoline Raulf from ANTS explain, "With application-oriented research on optimized paper recycling, we are making an essential contribution to the circular value creation of the material flow." "We assume that about 30 % of the discards could be reused," adds Philipp Nettesheim of the IPEM Chair. Thus, by recycling the additional recovered waste paper, the total annual CO2 emissions of the German paper industry could be reduced by 2.5%. In the course of this, the BMWK accepted our application under the 7th Energy Research Program "Innovations for the Energy Turnaround" with the support of EurA AG and decided to fund the project.