{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T06:53:17Z","timestamp":1778223197452,"version":"3.51.4"},"reference-count":55,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2019,11,20]],"date-time":"2019-11-20T00:00:00Z","timestamp":1574208000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BD\/91894\/2012"],"award-info":[{"award-number":["SFRH\/BD\/91894\/2012"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Energies"],"abstract":"<jats:p>The first part of the current reported work presents experimental results of brewers\u2019 spent grains gasification in a pilot-scale downdraft gasifier. The gasification procedure is assessed through various process characteristics such as gas yield, lower heating value, carbon conversion efficiency, and cold gas efficiency. Power production was varied from 3.0 to 5.0 kWh during the gasification experiments. The produced gas was supplied to an internal combustion engine coupled to a synchronous generator to produce electricity. Here, 1.0 kWh of electricity was obtained for about 1.3 kg of brewers\u2019 spent grains pellets gasified, with an average electrical efficiency of 16.5%. The second part of the current reported work is dedicated to the development of a modified thermodynamic equilibrium model of the downdraft gasification to assess the potential applications of the main Portuguese biomasses through produced gas quality indices. The Portuguese biomasses selected are the main representative forest residues (pine, eucalyptus, and cork) and agricultural residues (vine prunings and olive bagasse). A conclusion can be drawn that, using air as a gasifying agent, the biomass gasification provides a produced gas with enough quality to be used for energy production in boilers or turbines.<\/jats:p>","DOI":"10.3390\/en12234413","type":"journal-article","created":{"date-parts":[[2019,11,20]],"date-time":"2019-11-20T11:06:03Z","timestamp":1574247963000},"page":"4413","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["Experimental and Modeling Analysis of Brewers\u00b4 Spent Grains Gasification in a Downdraft Reactor"],"prefix":"10.3390","volume":"12","author":[{"given":"S\u00e9rgio","family":"Ferreira","sequence":"first","affiliation":[{"name":"CT2M\u2014Centre for Mechanical and Materials Technologies, Mechanical Engineering Department of Minho University, 4804-533 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3904-337X","authenticated-orcid":false,"given":"Eliseu","family":"Monteiro","sequence":"additional","affiliation":[{"name":"VALORIZA\u2014Research Center for Endogenous Resource Valorisation, Polytechnic Institute of Portalegre, 7300-555 Portalegre, Portugal"},{"name":"CIENER-LAETA\/Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8384-4433","authenticated-orcid":false,"given":"Lu\u00eds","family":"Calado","sequence":"additional","affiliation":[{"name":"VALORIZA\u2014Research Center for Endogenous Resource Valorisation, Polytechnic Institute of Portalegre, 7300-555 Portalegre, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2846-5785","authenticated-orcid":false,"given":"Valter","family":"Silva","sequence":"additional","affiliation":[{"name":"VALORIZA\u2014Research Center for Endogenous Resource Valorisation, Polytechnic Institute of Portalegre, 7300-555 Portalegre, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2581-4460","authenticated-orcid":false,"given":"Paulo","family":"Brito","sequence":"additional","affiliation":[{"name":"VALORIZA\u2014Research Center for Endogenous Resource Valorisation, Polytechnic Institute of Portalegre, 7300-555 Portalegre, Portugal"}]},{"given":"C\u00e2ndida","family":"Vilarinho","sequence":"additional","affiliation":[{"name":"CT2M\u2014Centre for Mechanical and Materials Technologies, Mechanical Engineering Department of Minho University, 4804-533 Guimar\u00e3es, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,20]]},"reference":[{"key":"ref_1","unstructured":"IEA (2018). 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