Zirconia oxygen sensor is used to measure the content of oxygen in the flue gas of large supercritical boiler furnace with zirconia ceramic sensor. It is a large number of boiler oxygen content measurement equipment, simple structure, rapid response, accurate measurement and other advantages.

Zirconia probe is the use of stable cubic zirconia ceramic in the above 650 ℃ environment produce oxygen ionic conduction properties and design, in a certain temperature conditions, if the zirconium dioxide gases on either side of the block ceramics exist in different oxygen concentration in the zirconium dioxide oxygen ion migration in ceramic, by zirconium dioxide leads on both sides of the electrode, measurable to stable millivolt level signal, we call it the oxygen potential. The sensor device consists of metal shell, measuring battery, heater, thermocouple, filter element and cable terminal. Measuring the battery ontology is divided into three layers: platinum (electrode) ─ zirconia (electrolyte) ─ platinum (electrode). Platinum electrodes are porous. The flue gas enters the measured gas side of the battery through a filter or test tube, and the other side is the reference air (20.60% oxygen content).

When two gases with different oxygen concentrations act on the battery to measure it, they produce a logarithmic potential (the larger the difference in oxygen concentrations on both sides, the larger the potential signal). The millivolt signal is converted to standard current of 0-10ma or 4-20ma by oxygen analyzer. This current is output by the connection terminal of oxygen analyzer. In practical engineering applications, one side of zirconia is fed into a gas with known oxygen concentration, which is called reference gas, such as air, standard gas, etc., while the other side is the gas measured, which is the flue gas in the furnace we want to test. The signal output from zirconia probe is the oxygen potential signal.