Inland Paperboard in Rome, Ga., had three black liquor recovery boilers that burned waste oil as an auxiliary fuel for startup and to supplement black liquor at higher steam rates. The plant experienced frequent scanner failures with the existing flame detector system and great difficulty discriminating between the liquor bed and oil flames. As a result, burner light-off required that the operator visit the burner front and close the scanner isolation valve before the light-off sequence.
Coen Co. Inc., Foster City, Calif., demonstrated an iScan flame scanner and installed it on one of the recovery boiler burners. A month later, Inland reported 100 percent reliability throughout numerous light-off sequences. The new scanner completely eliminated the discrimination problems. Plus, the operators no longer needed to open and close the scanner isolation valves, making the light-off sequence of burners a safer and easier operation.
The success led Inland to purchase the demonstration iScan flame scanner and replace the existing scanners on all the other burners. Six months later, Inland placed another order for Coen scanners to upgrade the second recovery boiler and reported significant cost savings as the old scanners failed regularly and required frequent replacement.