Circular economy system integrating biogas into process to produce high quality products from recycled paper
W.Hamburger paper and board production facility in Pitten, Austria. This short case story outlines the incorporation of anaerobic digestion into a facility producing 450,000 t of paper and board (from recycled paper). The wastewater facility incorporates a number of stages of anaerobic digestion facilities which treat 2 million m³ per annum of wastewater. The biogas is used in the boilers for steam generation and electricity and heat generation in a combined heat and power unit (CHP). The energy from biogas is used onsite at the production facility to provide energy for the industrial process and substitute the use of fossil fuel. Anaerobic digestion produces 5-6 million Nm³ of biogas per year, about 30,722 MWh, which is equivalent to 5% of primary energy demand at the facility.
In addition, the sludge from the on-site aerobic wastewater treatment plant is either incinerated to generate steam and power or managed off-site by external contractors.