Infrared FEGT measurement

Online FEGT Monitoring for Better Boiler Performance & Longer Plant Life

 

In thermal power plant, furnace exit gas temperature monitoring is essential for boiler safety, performance, emission control, etc. At furnace exit, boundary between lower radiative zone and upper convective zone, FEGT measurement system is installed to offer indication of heat transfer to water wall and boiler condition. Based on that, operators can make informed decision from boiler start-up to full load operation.

 

Traditional retractable temperature probe is outdated for following reasons:

 

  • Thermocouple malfunction
  • Travel mechanism failure
  • Measurement for a small point only
  • Available for start-up stage only

 

FEGT retractable probe

 

Non-Contact Infrared Thermometer For Continuous Online Measurement

 

Featured with precise measurement, high reliability, low maintenance, easy installation, infrared thermometers are widely used to monitor furnace gas temperature.

 

FEGT monitoring technology

 

Working Principle

 

Objects radiate heat energy in all states. Infrared thermometer can obtain temperature information by measuring infrared energy of corresponding band of the object itself. In combustion process of fossil fuel, massive CO2 gas is generated. Infrared thermometer is pre-set to detect hot CO2 gas spectrum and equipped with spectra filter (4.45um) to block other infrared emissions. This feature is designed for accurate measurement of CO2 gas temperature with its field of view.

 

Protection, Installation, Precision

 

FEGT measuring is difficult. Working under inhospitable condition, infrared thermometer is equipped with cooling jacket, air purging and filtering system to withstand hot corrosive gases and entrained flying particulates. IP65 can protect infrared sensor from dirts in outdoor environment.

 

Light weight and small size makes it easily installed at any boiler door or port without being an obstacle.

 

±1% accuracy with wide measuring range 0~1800℃ in 50:1 field of view.

 

Benefits

 

  • Direct indication of overheating or underheating to avoid potential damage during start-up.
  • Slagging control. When FEGT is higher than coal ashes melting point, fly ash will stick to tubes and pendants. This can result in tube corrosion, frequent soot blowing, lower boiler efficiency, higher fan power consumption. With temperature sensor, operators can set triggers to initiate soot blowing.
  • Optimize soot blower operation. Based on FEGT data, operators can make plan such as duration, sequence, frequency to minimize fouling. FEGT changes after soot blowing can examine cleaning performance.
  • Combustion tuning and reduce NOx and SO2 emission.
  • FEGT monitoring to ensure decompose of toxic in waste incinerator.
  • Fireball centering.

 

FEGT Monitoring provides accurate online measurement of furnace exit-gas temperature. By leveraging advanced infrared technology, this optical pyrometer ensures optimized combustion, improved efficiency and enhanced safety. It is an indispensable tool for modern power plants looking to improve operations and reduce costs while maintaining high safety level.