A new system from Siemens helps to reduce the amount of energy needed to manufacture paper, while also saving on disposal costs. This is possible because the system simply burns most of the waste that is generated during paper production. The resulting waste heat can be used to power a steam turbine, which in turn generates electricity for the paper plant. In addition, the facility can utilize the combustion heat for the paper production process.

The system — Sipaper Reject Power — was developed by production plant experts at Siemens in Erlangen and has been in use at a pilot facility for some time now. Mayr-Melnhof, an Austrian company and the world’s largest manufacturer of recycling carton, burns up to 50 tons of waste a day at its factory in Hirschwang near Vienna. The facility also burns fiber sludge and biosludge, as well as ‘rejects.’ Rejects are residues that don’t consist of paper fibers, including films, plastic, textiles, coatings and composite materials.

The materials are analyzed in a lab facility, which determines their energy content in order to create an optimum fuel mix. The system can use materials with a moisture content of up to 50 percent. Materials with greater moisture content require the use of an integrated gas burner or the addition of dry waste fuel to the mix. At Mayr-Melnhof, the admixture of waste wood even allows the system to burn sludge with a moisture content of 80 percent. A magnet is used to extract metallic objects such as staples. The residual material is pulverized and conveyed to a combustion chamber via a sophisticated transport system. The fuel is distributed evenly over the grate, with partial drying of the fuel already taking place in the airborne phase. Because the system reduces the amount of fossil fuels required for power generation, Sipaper Reject Power also helps to cut production of carbon dioxide, a greenhouse gas. What’s more, a flue gas purification system secures that pollutants produced during combustion are reduced to prescriptive limits.