Photo: Emerson Oxymitter 4000 monitor
Typical gas measurements for optimisation of the burning control in the boiler are measurement of O2 and CO.
For measurement of O2 zirconium-oxide, probes are often used after the incinerator, just prior to the economiser. In many large incineration plants, more oxygen probes are used on each line; partly to be able to average between different measurements, partly to be less vulnerable when a monitor is calibrated or serviced and partly to be able to monitor in different locations in the duct and thereby compensate for any possible stratification.
The measurement of CO for optimisation of the burning control is not quite as widespread as the measurement of O2. During many years, the measurement of CO after the boiler has been used as emission measurement and was accepted in "the old" Directive on the Incineration of Waste. However, according to the new "Directive on the Incineration of Waste, 2000/76/EC", CO is to be monitored after the last cleaning. This means that many monitors are to be removed or exchanged.
The future "standard" in instrumentation for gas analysis is difficult to foresee. We believe that measurement of CO by laser light is a future trend; a measurement principle with short response times functioning in high temperatures and high dust loads and which requires a minimum of maintenance.
- Measurement of O2 after the boiler and before the economiser
- Measurement of O2 with a zirconium-oxide probe such as Emerson Oxymitter 4000
- Measurement of CO after the boiler and before the economiser
- Measurement of CO with an extractive analysis system such as GASloq 600 with an ABB Uras 14 monitor
- Measurement of CO with an in-situ analyzer such as the NEO LaserGas Monitor
- Demands for a robust measurement in high temperatures and high dust loads
- Demands for short response times for boiler optimisation