http://hdl.handle.net/10854/6234 2026-04-17T10:27:09Z http://hdl.handle.net/10854/6608 Biomass fuel production from cellulosic sludge through biodrying: Aeration strategies, quality of end-products, gaseous emissions and techno-economic assessment Guerra Gorostegui, Nagore; González, Daniel; Puyuelo Sánchez, Belén; Ovejero García, Jonatan; Colón Jordà, Joan; Gabriel, David; Sánchez, Antoni; Ponsá Salas, Sergio This study assesses the technological, environmental and economic feasibility of biodrying to valorise cellulosic sludge as a renewable energy source. Specifically, three different aeration strategies were compared in terms of biodrying performance, energetic consumption, gaseous emissions, quality of end-products and techno-economic analysis. These strategies were based on different combinations of convective drying with biogenic heat produced. Two innovative biodrying performance indicators (Energetic Biodrying Index and Biodrying Performance Index) were proposed to better assess the initial and operational conditions that favour the maximum energy process efficiency and the highest end-product quality. The end-products obtained consistently presented moisture contents below 40% and lower heating values above 9.4 MJ·kg-1. However, the best values achieved were 32.6% and 10.4 MJ·kg-1 for moisture content and lower heating value, respectively. Low N2O and CH4 emissions confirmed the effective aeration of all three strategies carried out, while NH4 and tVOCs were related either to temperature or biological phenomena. A techno-economic analysis proved the economic viability and attractiveness of the biodrying technology for cellulosic sludge in all the strategies applied. 2021-01-01T00:00:00Z http://hdl.handle.net/10854/6235 Filling in sewage sludge biodrying gaps: Greenhouse gases, volatile organic compounds and odour emissions González, Daniel; Guerra Gorostegui, Nagore; Colón Jordà, Joan; Gabriel, David; Ponsá Salas, Sergio; Sánchez, Antoni In the present work, a complete study of the sewage sludge (SS) biodrying technology was conducted at benchscale, aiming at assessing its performance and providing a valuable insight into the different gaseous emission patterns found for greenhouse gases (GHG) and odorant pollutants. As process key parameters, temperature, specific airflow, dynamic respiration index, final moisture content and Lower Calorific Value (LCV) were evaluated. At the end of the biodrying, a product with a 35.9% moisture content and a LCV of 7.1 MJ·kg−1product was obtained. GHGs emission factor was 28.22 kgCO2eq per Mg of initial mass of dry matter in the SS (DM0-SS). During the biodrying process, maximum odour concentration measured was 3043 ou·m−3 and the estimated odour emission factor of the biological treatment was 3.10E+07 ou per Mg DM0-SS. Finally, VOCs were completely identified and quantified. The most abundant VOCs found in the biodrying gaseous emissions were terpenes, sulphur-compounds and ketones. 2019-01-01T00:00:00Z