150 likes | 338 Vues
Lecture Notes V Oxygen sensors based on oxygen ion conductors. Dependence of domain boundaries on oxygen pressure and temperature. P p. p-cond. P p. Ionic domains. n-cond. P n. P n. Function. 1. / 4F. Porous Pt electrodes – reactions takes place in triple points. Calibration curve.
E N D
Lecture Notes VOxygen sensors based on oxygen ion conductors
Dependence of domain boundaries on oxygen pressure and temperature Pp p-cond. Pp Ionic domains n-cond Pn Pn
Function 1 /4F Porous Pt electrodes – reactions takes place in triple points
Calibration curve Short circuit due to electronic conduction
High temperature oxygen sensors • Temperature range: 600 - 1500ºC • Pressure range becomes smaller with increasing temperature. • Good resistance toward corrosive atmospheres. • Good temperature shock resistance. • It is the equilibrium oxygen pressure which is measured!
In-situ measurements Examples: - Combustion control in gas- and coal fired furnaces; - Combustion of waste; • Atmosphere control in sintering and heat treatment • furnaces.
In-situ oxygen control in molten steel. Electrolyte, Belgium
- sensor Engine Exhaust Control unit Catalytic emission-control
Extractive control of welding gases Welding of stainless steel. TIG- tungsten inert gas welding Argon Gas on backside must be controlled.
Extractive control of welding gases TIG- tungsten inert gas welding Argon PBI-Dansensor
Atmosphere control Fluid N2 850 m3/h Nitrogen freeze dryer
Extractive quality control Packed meat and vegetables. PBI-Dansensor
Repetition How function an oxygen sensor? Typical applications of oxygen sensors.