Temperature-Corrected Oxygen Detection Based on Multi-Mode Diode Laser Correlation Spectroscopy

Figure 3

Experimental setup for oxygen measurements by MDL-COSPEC technique, with the electronic section (above) and the measurement section (below) divided in three different schemes to simulate coal-combustion exhaust gas monitoring at the tail of flue. (a) Both sample and reference cells were purged with nitrogen gas and heated to the same temperature conditions; (b) the sample cell was purged with nitrogen gas, and oxygen in open air at room temperature was used as a reference gas; (c) a three-zone sample gas cell was employed with both end sections sealed with nitrogen gas, and oxygen in open air at room temperature was used as a reference gas.