title: An Assessment of Three Different In Situ Oxygen Sensors for Monitoring Silage Production and Storage.
abstract: Oxygen (O₂) concentration inside the substrate is an important measurement for silage-research and-practical management. In the laboratory gas chromatography is commonly employed for O₂ measurement. Among sensor-based techniques, accurate and reliable in situ measurement is rare because of high levels of carbon dioxide (CO₂) generated by the introduction of O₂ in the silage. The presented study focused on assessing three types of commercial O₂ sensors, including Clark oxygen electrodes (COE), galvanic oxygen cell (GOC) sensors and the Dräger chip measurement system (DCMS). Laboratory cross calibration of O₂ versus CO₂ (each 0-15 vol.%) was made for the COE and the GOC sensors. All calibration results verified that O₂ measurements for both sensors were insensitive to CO₂. For the O₂ in situ measurement in silage, all O₂ sensors were first tested in two sealed barrels (diameter 35.7 cm; height: 60 cm) to monitor the O₂ depletion with respect to the ensiling process (Test-A). The second test (Test-B) simulated the silage unloading process by recording the O₂ penetration dynamics in three additional barrels, two covered by dry ice (0.6 kg or 1.2 kg of each) on the top surface and one without. Based on a general comparison of the experimental data, we conclude that each of these in situ sensor monitoring techniques for O₂ concentration in silage exhibit individual advantages and limitations.
authors.affiliation: College of Information and Electrical Engineering, China Agricultural University, Key Lab of Agricultural Information Acquisition Technology, Ministry of Agriculture, 100083 Beijing, China. sgl@cau.edu.cn.
authors.forename: Guilin
authors.initials: G
authors.lastname: Shan
authors.affiliation: College of Information and Electrical Engineering, China Agricultural University, Key Lab of Agricultural Information Acquisition Technology, Ministry of Agriculture, 100083 Beijing, China. pal@cau.edu.cn.
authors.forename: Yurui
authors.initials: Y
authors.lastname: Sun
authors.affiliation: College of Information and Electrical Engineering, China Agricultural University, Key Lab of Agricultural Information Acquisition Technology, Ministry of Agriculture, 100083 Beijing, China. naaiocean@163.com.
authors.forename: Menghua
authors.initials: M
authors.lastname: Li
authors.affiliation: Department of Agricultural Engineering, The University of Bonn, 53115 Bonn, Germany. kjungblu@uni-bonn.de.
authors.forename: Kerstin H
authors.initials: KH
authors.lastname: Jungbluth
authors.affiliation: Department of Agricultural Engineering, The University of Bonn, 53115 Bonn, Germany. c.maack@uni-bonn.de.
authors.forename: Christian
authors.initials: C
authors.lastname: Maack
authors.affiliation: Department of Agricultural Engineering, The University of Bonn, 53115 Bonn, Germany. buescher@uni-bonn.de.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Buescher
authors.affiliation: Department of Agricultural Engineering, The University of Bonn, 53115 Bonn, Germany. kschuet1@uni-bonn.de.
authors.forename: Kai-Benjamin
authors.initials: KB
authors.lastname: Schütt
authors.affiliation: Department of Agricultural Engineering, The University of Bonn, 53115 Bonn, Germany. boeker@uni-bonn.de.
authors.forename: Peter
authors.initials: P
authors.lastname: Boeker
authors.affiliation: Department of Agricultural Engineering, The University of Bonn, 53115 Bonn, Germany. lammers@uni-bonn.de.
authors.forename: Peter Schulze
authors.initials: PS
authors.lastname: Lammers
authors.affiliation: College of Information and Electrical Engineering, China Agricultural University, Key Lab of Agricultural Information Acquisition Technology, Ministry of Agriculture, 100083 Beijing, China. zhouhy@cau.edu.cn.
authors.forename: Haiyang
authors.initials: H
authors.lastname: Zhou
authors.affiliation: College of Information and Electrical Engineering, China Agricultural University, Key Lab of Agricultural Information Acquisition Technology, Ministry of Agriculture, 100083 Beijing, China. chengqiang@cau.edu.cn.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Cheng
authors.affiliation: College of Information and Electrical Engineering, China Agricultural University, Key Lab of Agricultural Information Acquisition Technology, Ministry of Agriculture, 100083 Beijing, China. madaokun@cau.edu.cn.
authors.forename: Daokun
authors.initials: D
authors.lastname: Ma
mesh_terms: D000383:Agriculture / Q000295:instrumentation*; D002138:Calibration; D002245:Carbon Dioxide / Q000032:analysis*; D004566:Electrodes; D004581:Electronics / Q000295:instrumentation*; D004867:Equipment Design; D010100:Oxygen / Q000032:analysis*; D012820:Silage / Q000032:analysis*
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen
keywords: Clark oxygen electrodes (COE); Dräger chip measurement system (DCMS); carbon dioxide (CO2); galvanic oxygen cell (GOC); oxygen (O2); silage