{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T22:17:02Z","timestamp":1791325022607,"version":"4.3.1"},"reference-count":35,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,5,11]],"date-time":"2023-05-11T00:00:00Z","timestamp":1683763200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Fachagentur f\u00fcr Nachwachsende Rohstoffe (FNR) on behalf of the Federal Ministry of Food and Agriculture (BMEL)","award":["22038718"],"award-info":[{"award-number":["22038718"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In view of the tremendous emissions of toxic gases and particulate matter (PM) by low-power firewood-fueled fireplaces, there is an urgent need for effective measures to lower emissions to keep this renewable and economical source for private home heating available in the future. For this purpose, an advanced combustion air control system was developed and tested on a commercial fireplace (HKD7, Bunner GmbH, Eggenfelden, Germany), complemented with a commercial oxidation catalyst (EmTechEngineering GmbH, Leipzig, Germany) placed in the post-combustion zone. Combustion air stream control of the wood-log charge combustion was realized by five different control algorithms to describe all situations of combustion properly. These control algorithms are based on the signals of commercial sensors representing catalyst temperature (thermocouple), residual oxygen concentration (LSU 4.9, Bosch GmbH, Gerlingen, Germany) and CO\/HC-content in the exhaust (LH-sensor, Lamtec Mess- und Regeltechnik f\u00fcr Feuerungen GmbH &amp; Co. KG, Walldorf (Germany)). The actual flows of the combustion air streams, as calculated for the primary and secondary combustion zone, are adjusted by motor-driven shutters and commercial air mass flow sensors (HFM7, Bosch GmbH, Gerlingen, Germany) in separate feedback control loops. For the first time, the residual CO\/HC-content (CO, methane, formaldehyde, etc.) in the flue gas is in-situ monitored with a long-term stable AuPt\/YSZ\/Pt mixed potential high-temperature gas sensor, which allows continuous estimation of the flue gas quality with an accuracy of about \u00b110%. This parameter is not only an essential input for advanced combustion air stream control but also provides monitoring of the actual combustion quality and logging of this value over a whole heating period. By many firing experiments in the laboratory and by field tests over four months, it could be demonstrated that with this long-term stable and advanced automated firing system, depression of the gaseous emissions by about 90% related to manually operated fireplaces without catalyst could be achieved. In addition, preliminary investigations at a firing appliance complemented by an electrostatic precipitator yielded PM emission depression between 70% and 90%, depending on the firewood load.<\/jats:p>","DOI":"10.3390\/s23104679","type":"journal-article","created":{"date-parts":[[2023,5,12]],"date-time":"2023-05-12T01:30:29Z","timestamp":1683855029000},"page":"4679","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Extensive Gaseous Emissions Reduction of Firewood-Fueled Low Power Fireplaces by a Gas Sensor Based Advanced Combustion Airflow Control System and Catalytic Post-Oxidation"],"prefix":"10.3390","volume":"23","author":[{"given":"Xin","family":"Zhang","sequence":"first","affiliation":[{"name":"Institute for Sensor and Information Systems (ISIS), Karlsruhe University of Applied Sciences, Moltkestr. 30, D-76133 Karlsruhe, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1391-6080","authenticated-orcid":false,"given":"Binayak","family":"Ojha","sequence":"additional","affiliation":[{"name":"Institute for Sensor and Information Systems (ISIS), Karlsruhe University of Applied Sciences, Moltkestr. 30, D-76133 Karlsruhe, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hermann","family":"Bichlmaier","sequence":"additional","affiliation":[{"name":"Ulrich Brunner GmbH, Zellhuber Ring 17-18, D-84307 Eggenfelden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ingo","family":"Hartmann","sequence":"additional","affiliation":[{"name":"Deutsches Biomasseforschungszentrum Gemeinn\u00fctzige GmbH (DBFZ), Torgauer Str. 116, D-04347 Leipzig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Heinz","family":"Kohler","sequence":"additional","affiliation":[{"name":"Institute for Sensor and Information Systems (ISIS), Karlsruhe University of Applied Sciences, Moltkestr. 30, D-76133 Karlsruhe, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"101010","DOI":"10.1016\/j.rineng.2023.101010","article-title":"Agroforest woody residual biomass-to-energy supply chain analysis: Feasible and sustainable renewable resource exploitation for an alternative to fossil fuels","volume":"17","author":"Nunes","year":"2023","journal-title":"Results Eng."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"106841","DOI":"10.1016\/j.envint.2021.106841","article-title":"A critical review of pollutant emission factors from fuel combustion in home stoves","volume":"157","author":"Shen","year":"2021","journal-title":"Environ. 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