Fast measurement - direct control
The target of combustion control is an as uniform as possible distribution of the temperature in the combustion chamber. This leads to clear benefits for plant operation:
- Higher efficiency
- Reduced emissions
- More effective denitrification
- Less slagging and corrosion
In waste incineration plants the gas temperature behind secondary air is an early indicator for combustion which precedes the steam output by several minutes. By integrating the fast temperature signal into the combustion control the control loop can be significantly improved. This allows a uniform combustion and a stable steam output due to a faster intervention into the combustion process.
Improvement of control quality of up to 40 %
By the integration of the fast gas temperature signal the standard deviation of the control fluctuation (1-minute-values) can be reduced by 20-30 %. Thereby large performance- and temperature fluctuations decrease at least by a factor of 2-3. Reductions of the standard deviation of more than 40 % are possible in case of the combination with an active balancing control and a stronger primary air operation.
Control fluctuations below 3 % achievable
Until recent years, control fluctuations of the steam output of 5-7 % were considered good. With the integration of the gas temperature today values below 3 % are achievable. In the RDF power plant Weener a reduction of the standard deviation of 4.5 % to 2.1 % was achieved by the integration of the gas temperature into the control circuit. This corresponds to a reduction of the fluctuations of the steam output of 3.9 t/h to 1.8 t/h
Lower temperature fluctuations have further advantages
In addition to the more uniform steam output, the reduction of the temperature fluctuations offers further advantages. More constant temperatures facilitate the denitrification (SNCR). Lower temperature peaks reduce slagging and corrosion, thus ensuring a longer life cycle of the system.
Precise and reliable gas temperatures as a basis for combustion control
Our acoustic gas temperature measurement system agam provides precise and reliable gas temperatures, and since the 90s it is the basis for the optimization of the combustion control in many power plants and waste incinerators.