Innovation to reduce energy consumption and CO2 emissions during paper drying

The simulation-supported optimisation technology for drying a paper machine enables a significant increase in energy efficiency with a sustainable reduction in CO2 emissions. A modern paper/cardboard machine consumes almost 80% of the total energy requirement of a paper mill and causes almost half of all CO2 emissions. The main reasons for avoidable energy losses are, on the one hand, insufficient measurement data quality or unavailable measurement sensors for relevant process variables and, on the other hand, control loops that operate independently of each other but are linked in terms of process technology.

Current systems use process values from field instrumentation to control production. However, many important process variables are difficult or impossible to measure (e.g. dry content of the paper web after the press section, temperature of the drying cylinders, evaporation rates, air humidity, efficiency of heat exchangers and much more). This is state of the art, a limiting factor of current control technologies.

AutomationX combines measured values with physical process dependencies and device functions and maps the real drying process as a virtual system. The digital representation of the real sub-processes is carried out with the help of rigorous models from the field of thermodynamics. This results in a remarkable improvement in the quality and quantity of process information.

Using "What If" scenarios, i.e. virtual validation of modified process operating modes that cannot be carried out on the real machine for safety or production-related reasons, significant potential savings in terms of energy (steam, electrical) are identified in an offline simulation. AutomationX ePM DryEnd integrates the virtual representation of the real drying process into the model-based optimisation solution and enables online closed-loop control of the system.

Thanks to the high quality of the calculated optimum process operation, the system can be operated close to the physical and process-related limitations and enables the existing energy-saving potential to be maximised.

The solutions already implemented, including at Moritz J. Weig GmbH & Co. KG in Mayen, show savings of more than 4.5% live steam over the entire drying process.