A multi-level biogas model to optimise the energy balance of full-scale sewage sludge conventional and THP anaerobic digestion. (October 2020)

• Record Type: Journal Article
• Authors: Liu, Jin; Smith, Stephen R.
• Is Part Of: Renewable energy. Volume 159(2020)
• Page Start: 756
• Page End: 766
• Publication Date: 2020-10
• Subjects: Anaerobic digestion -- Biogas yield -- Digestion conditions -- Energy balance -- Process optimisation -- Sewage sludge; Renewable energy sources -- Periodicals; Power resources -- Periodicals; Énergies renouvelables -- Périodiques; Ressources énergétiques -- Périodiques; 333.794
• DOI: 10.1016/j.renene.2020.06.029
• Languages: English
• ISSNs: 0960-1481

Abstract

Abstract: Anaerobic digestion (AD) is a long-established method for treating wastewater sludge and has been extensively researched, but there remains a lack of generic or practical modelling tools to guide operators and maximise the energy output. Detailed kinetic models have been developed, but are too complex as practical tools for industrial level application. A multi-level model of biogas yield (BY) was therefore developed based on operational data from 72 full-scale sites in the UK showing a wide range of AD performance. The model focused on the controllable operational parameters that are currently monitored at full-scale, including: temperature, hydraulic retention time and dry solids content in the feed sludge. The model effectively described performance variations in BY of full-scale processes, and provides a practical management tool to aid decision support to improve AD efficiency and net energy balance. Graphical abstract: Image 1 Highlights: Up to 7 years of operational data from 72 full-scale AD sites was examined. A practical, operationally based sewage sludge MAD biogas model was developed. AD performance was significantly correlated to major operational process variables. Effects of operational parameters on BY with THP are equivalent to conventional MAD. Optimisation strategies are proposed to improve the overall AD energy balance.