Cross-Stack CO Analyzer
The importance of controlling excess air levels in various combustion processes has been recognized for many years. Now, however, the high cost of fuel makes it an economic necessity to reduce excess air levels to minimize thermal stack losses. In addition to increasing fuel costs, tightening environmental restrictions also can impact the optimization reduction of NOx also lead to incomplete combustion efficiency energy loss.

This requires achieving minimum unburned combustibles, as well as thermal stack losses. More precise control of air/fuel ratio, optimized for minimum total energy loss, can yield significant gains in efficiency and result in substantial savings in reduced fuel consumption and improved environmental performance.

Flue gas concentration of CO is a reliable and accurate indication of burner flame stoichiometry and the completeness of combustion. It is the most sensitive indicator of unburned combustibles loss. Used as a primary combustion efficiency parameter, in conjunction with oxygen analysis, a CO measurement offers additional advantages in controlling combustion at optimum levels of excess air to a combustion control scheme using an oxygen measurement only. Controlling air/fuel ratio to an optimum level of CO assures minimum total energy loss and maximum efficiency, independent of variations in boiler load, fuel type and fuel quality. The measurement is relatively unaffected by air in-leakage and burner maintenance requirements are immediately identified.

Emerson Process Management's reliable CO measurement, coupled with small, lightweight packaging and ease of operation and maintenance, assures you of years of trouble-free service from the Model CCO 5500 Carbon Monoxide (CO) Analyzer.

PRINCIPLE OF OPERATION
The Model CCO 5500 Carbon Monoxide (CO) Analyzer uses infrared absorption spectroscopy to continuously measure CO concentration in combustion flue gases. The infrared source is mounted directly on the flue gas duct or stack on the side opposite from the receiver. Infrared energy is radiated by the source, through a chopper across the duct to the receiver. The receiver employs gas filter correlation and narrow band-pass optical filtration with two solid state detectors to determine the absorption of radiation by CO in the flue gas.

Infrared energy, radiated by the source, passes through the flue gas, where a portion of the energy is absorbed by any CO present. The remaining energy passes through the receiver window, focusing lens and is split by a beam splitter. The split beam is directed to two separate detectors, the process measurement detector and the reference detector. The process detector reads the infrared signal coming from the CO in the combustion flue gases. The rest of the beam is redirected to the reference detector where it is filtered through a known concentration of CO. The two energy levels are sensed by the detectors and the signals are sent to the electronics. The resulting signals are ratioed and compared with the ratioed signals developed under CO calibration conditions.

Data Sheet