Synthesis of Biogas Supply Network Based on Experimental Data from Lab-Scale Anaerobic Digestion of Sewage Sludge and Organic Waste

Abstract

The aim of this work was to perform synthesis of biogas supply network based on the experimental data from laboratory-scale anaerobic digestion (AD) experiments. Experiments were performed with various types of organic waste and sewage sludge, such as different types of sewage sludge from municipal and industrial wastewater treatment plants, waste from vegetable oil, wine, dairy and meat processing industry, lignocellulosic waste and bio-plastic waste. The synthesis problem was formulated as a mixed-integer linear program (MILP) and was solved by using General Algebraic Modelling System (GAMS) software with the main objective of maximizing economic profit. The synthesis is demonstrated on an illustrative case study of up to three biogas plants in Slovenia. Three scenarios were considered with different prices of waste materials. The study showed good agreement between the model and experimental results. Results demonstrated that biogas production could be profitable by using considered waste materials only if biogas plant was paid for processing the substrates. Up to 6 GWh/y of electricity could be produced with the profit of about 2·106 $/y where prices of waste materials were around 80 $/t.