Anaerobic Digestion processes to produce biogas and in the future hydrogen is increasing in importance world wide. Sustainable solutions for renewable energy production systems are high on the agenda, due to global warming. Anaerobic Digestion is increasingly converting heterogeneous biomasses from the primary agricultural sector and by-products from the bioprocessing industries. The biogas produced is utilised in combined heat and power systems or as fuel in the transportation sector. In Denmark 3.rd generation biogas plant projects are planned and under construction before 2015. What type of biogas plants will they be, and what have been learned from the last 2 decades of biogas plants.
The more detailed studies concerns at-line and on-line PAT (Process Analytical Technology) developments of monitoring the anaerobic digestion processes. The aim was to investigate if the change in the biomass composition could be detectable by NIR measurements. Results show that several key monitoring intermediates in the anaerobic fermentation process can be quantified directly by NIR with good performance, especially total solids, volatile solids, ammonium and total volatile fatty acids. A newly developed method, for on-line NIR and/or other sensor technologies for monitoring and managing of biogas fermentation processes will be documented and implemented in full scale biogas plants, offering a robust, and low-budget PAT approach to a bulky bioenergy industry in a rapid growth.