Emerging techniques of mid-infrared absorption spectroscopy offer potentially great sensitivity and selectivity for combustion control and emission monitoring. Because of that, a difference frequency based mid-infrared absorption spectrometer has been considered for application in the glass industry. Based on preliminary tests within laboratory conditions. a spectrometer which operates at wavelengths around 5um was applied to online monitoring of the atmosphere of a gas fired melting furnace. The CO concentration was measured in order to demonstrate the feasibility of a mid-infrared absorption spectrometer for process control in the glass industry. A series of measurements was performed in situ as well as crossing the recuperator entry, resulting in general advice on the construction of a prototype device.
