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Show LOW-NOx DRB-XCL® PC BURNERS FOR PLUG-IN RETROFIT APPLICATIONS Hamid Sarv McDermott Technology, Inc. Research and Development Division Alliance, O H and Albert D. La Rue Babcock & Wilcox Utility Power & Industrial Division Barberton, O H 1997 AFRC International Symposium, Chicago, IL ABSTRACT Many conventional wall-fired boilers use fast mixing and high velocity pulverized coal (PC) circular burners which generate high N O x emissions. Significant downtime and expenses can be associated with boiler modifications to retrofit the smaller diameter high velocity burners with the larger throat and lower velocity low-NOx burners. Development of an effective plug-in low-NOx burner that easily replaces a high-NOx burner would provide a more cost-effective means of meeting the emissions regulations. A plug-in adaptation of the commercially successful Babcock & Wilcox (B&W) DRB-XCL ® low-NOx P C burner was developed and optimized at 100 million Btu/hr in a large-scale pilot facility with a high volatile eastern bituminous Ohio Mahoning coal. Effects of excess air, thermal load, and fuel variations on the combustion and emissions performance of the burner were investigated. The plug-in D R B - X C L ® P C burner can meet or exceed existing requirements for N O x , C O , and LOI (loss on ignition) in low-NOx retrofits. At a typical operating condition of 1 7 % excess combustion air (3.2% stack 02) and without an overfire air system, average N O x, C O , and LOI values for a plug-in and swirler-equipped configuration were 249 P P M V (0.34 lb NO2/106 Btu), 11 P P M V , and 1.9%, respectively. The success of these tests enables commercial use of the D R B - X C L ® P C burners in plug-in applications. 1 |