{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T04:10:11Z","timestamp":1768709411225,"version":"3.49.0"},"reference-count":40,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,1,27]],"date-time":"2021-01-27T00:00:00Z","timestamp":1611705600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002848","name":"Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica","doi-asserted-by":"publisher","award":["Anillo Miner\u00eda ACM170008"],"award-info":[{"award-number":["Anillo Miner\u00eda ACM170008"]}],"id":[{"id":"10.13039\/501100002848","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Agencia Nacional de Investigaci\u00f3n y Desarrollo","award":["Beca de Doctorado Nacional\/2020-21200399"],"award-info":[{"award-number":["Beca de Doctorado Nacional\/2020-21200399"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, a novel optical technique for following the progress of the blister copper desulfurization process is presented. The technique is based on the changes observed in the continuous spectrum of the visible\u2013near-infrared (VIS\u2013NIR) radiation that the blister melt emits while the chemical reactions of the sulfur elimination process are taking place. Specifically, the proposed technique uses an optical probe composed of an optical fiber, a collimating lens, and a quartz tube, which is immersed in the melt. This optical probe provides a field of view of the blowing zone where the desulfurization reaction occurs. The experimental results show that the melt VIS\u2013NIR total irradiance evolves inversely to the SO2 concentration reported by a gas analyzer based on differential optical absorption spectroscopy. Furthermore, the blister copper spectral emissivity as well as the total emissivity observed throughout the process show strong correlation with the sulfur content during desulfurization reaction.<\/jats:p>","DOI":"10.3390\/s21030842","type":"journal-article","created":{"date-parts":[[2021,1,27]],"date-time":"2021-01-27T12:20:26Z","timestamp":1611750026000},"page":"842","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["A Radiometric Technique for Monitoring the Desulfurization Process of Blister Copper"],"prefix":"10.3390","volume":"21","author":[{"given":"Alejandro","family":"V\u00e1squez","sequence":"first","affiliation":[{"name":"Metallurgical Engineering Department, University of Concepci\u00f3n, Edmundo Larenas 285, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2390-2133","authenticated-orcid":false,"given":"Francisco","family":"P\u00e9rez","sequence":"additional","affiliation":[{"name":"Electrical Engineering Department, University of Concepci\u00f3n, Edmundo Larenas 219, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maximiliano","family":"Roa","sequence":"additional","affiliation":[{"name":"Metallurgical Engineering Department, University of Concepci\u00f3n, Edmundo Larenas 285, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6419-1211","authenticated-orcid":false,"given":"Ignacio","family":"Sanhueza","sequence":"additional","affiliation":[{"name":"Electrical Engineering Department, University of Concepci\u00f3n, Edmundo Larenas 219, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hugo","family":"Rojas","sequence":"additional","affiliation":[{"name":"Metallurgical Engineering Department, University of Concepci\u00f3n, Edmundo Larenas 285, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4370-7423","authenticated-orcid":false,"given":"Victor","family":"Parra","sequence":"additional","affiliation":[{"name":"Metallurgical Engineering Department, University of Concepci\u00f3n, Edmundo Larenas 285, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5993-5933","authenticated-orcid":false,"given":"Eduardo","family":"Balladares","sequence":"additional","affiliation":[{"name":"Metallurgical Engineering Department, University of Concepci\u00f3n, Edmundo Larenas 285, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0567-0188","authenticated-orcid":false,"given":"Roberto","family":"Parra","sequence":"additional","affiliation":[{"name":"Metallurgical Engineering Department, University of Concepci\u00f3n, Edmundo Larenas 285, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6193-9949","authenticated-orcid":false,"given":"Sergio","family":"Torres","sequence":"additional","affiliation":[{"name":"Electrical Engineering Department, University of Concepci\u00f3n, Edmundo Larenas 219, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"893","DOI":"10.1016\/j.mineng.2003.08.002","article-title":"Review of copper pyrometallurgical practice: Today and tomorrow","volume":"16","author":"Moskalyk","year":"2003","journal-title":"Miner. 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