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Show ABB CE's Concentric Firing Technique '\ \ \ \ \ Primary Air. and Coal \ \ \ Offset Air \ \ \ ./ ./ ./ ./ ./ ./ \ \ ./ ./ \ \ \ .........: ./ ./ \ \ \ \ Fuel Lean Zone / \ \ \ Figure 4: ABB CE's Tangential Firing Technique IV. TEST PROGRAM DESCRIPTION The stepwise retrofit of the previously described NOx control technologies requires that three outages be scheduled at each plant. The wall-frred project required outages to install the following: (1) test instrumentation, (2) AOFA system. and (3) LNBs. These outages were scheduled to coincide with existing plant maintenance outages in October 1989, April 1990, and March 1991. This planned retrofit progression allows for an evaluation of AOF A while operating with the existing burners. The T -frred project schedule calls for (1) installation of the instrumentation in October 1990, (2) installation of the LNCFS Level II in April 1991, and (3) installation of LNCFS Level III in October 1991. LNCFS Level I will be demonstrated by closing off the SOFA system in LNCFS Level III. Following each outage. a series of four groups of tests will be performed. These are (1) diagnostic. (2) performance. (3) long-term, and (4) verification. The diagnostic, performance, and verification tests consist of short-term data collection during carefully established operating conditions. The diagnostic tests are designed to map the effects of changes in boiler operation on NOx emissions. The performance tests evaluate a more comprehensive set of boiler and combustion performance indicators. The results from these tests will include particulate characteristics. boiler efficiency, and boiler outlet emissions. Mill performance and air flow distribution are also tested. As stated previously, the primary objective of the demonstrations is the collection of long-term. statistically significant quantities of data under nonnal operating conditions with and without the various NOx reduction technologies. Earlier demonstrations of emissions control technologies have relied solely on data from a matrix of carefully established short-term (one- to four-hour) tests. However. boilers are not typically operated in this 7 |