How zirconia oxygen probes can help maximize rotary air pre-heater efficiency

Using an air pre-heater to recover waste heat from flue gases can make up to a 10% difference to overall efficiency. Commonly installed in many power stations, rotating plate air preheaters collect heat from the flue gas stream and release it to the boiler air stream to preheat the combustion air supply.

A typical problem with these types of pre-heaters is air leakage caused by deterioration of the seals that divide the combustion air and flue gas streams. If left untreated, this problem can see losses of up to 30%, putting added strain on the Forced Draft – or FD – fan to compensate and increasing its demand for power.

This animation shows how using ABB’s AZ20 zirconia oxygen probes to continuously measure excess oxygen levels can help to spot leaks caused by worn and / or leaking seals.