Cyclone reburn using coal-water fuel: Pilot-scale development and testing

There is an ongoing effort to develop retrofit technologies capable of converting oil- and/or gas-fired boilers to coal combustion. The objective of this project is to demonstrate the technical feasibility of an improved portion of a previously developed retrofit system designed for the purpose of converting oil/gas boilers. This improvement would almost entirely eliminate the use of premium fuels, thereby significantly increasing the economical attractiveness of the system. Specifically, the goals in this program were to replace natural gas as a reburning fuel with coal-water fuel (CWF). The advantages of such a system include: (1) increased return on investment (ROI) for conversions; (2) nearly complete elimination of premium oil or gas fuel; (3) a more integrated approach to the conversion of oil- or gas-designed boilers to CWF

Full-scale demonstration of Low-NO{sub x} Cell{trademark} Burner retrofit: Long-term testing

The Low-NO{sub x} Cell{trademark} Burner (LNCB) concept was developed by Babcock & Wilcox (B&W) to effectively reduce the NO{sub x} emissions from pulverized-coal-fired boilers equipped with cell burners. These boilers were built mostly in the mid to late 1960s. Small (6-million Btu/hr) and intermediate (100-million Btu/hr) prototype versions of the concept were developed jointly by B&W and the Electric Power Research Institute (EPRI) during the mid-to-late 1980s. The design of B&W LNCBs allows direct replacements of the originally installed cell burners without pressure-part modifications. During this US Department of Energy (DOE) Clean Coal III program, Dayton Power and Light Company (DP&L) served as the host utility using its J.M. Stuart Station Unit {number_sign}4 (JMSS 4) for the first full-scale LNCB demonstration. This unit has a rated output capacity of 605 MW{sub e}. After the LNCB retrofit and burner optimization contract phases in late 1991, JMSS 4 underwent a long- term (nine months) test period from July 1992 to March 1993. The objective of this test was to determine the overall performance of this boiler after the LNCB retrofit. The long-term test involved determinations of the boiler emission performance and evaluations of waterwall corrosion potential, as well as a study of the overall operability of the LNCB system. Specific tasks performed during this long-term test include: (1) laboratory corrosion study; (2) field corrosion panel study; (3) in-furnace gas species probing; and (4) boiler emissions performance study. This report summarizes the long- term test results

Full-scale demonstration of low-NO{sub x} cell{trademark} burner retrofit. Final report

The objective of the Low-NO{sub x} Cell{trademark}Burner (LNCB{trademark}) demonstration is to evaluate the applicability of this technology for reducing NO{sub x} emissions in full-scale, cell burner-equipped boilers. More precisely, the program objectives are to: (1) Achieve at least a 50% reduction in NO{sub x} emissions. (2) Reduce NO{sub x} with no degradation to boiler performance or life of the unit. (3) Demonstrate a technically and economically feasible retrofit technology. Cell burner equipped boilers comprise 13% of the Pre-New Source Performance Standards (NSPS) coal-fired generating capacity. This relates to 34 operating units generating 23,639 MWe, 29 of which are opposed wall fired with two rows of two-nozzle cell burners on each wall. The host site was one of these 29. Dayton Power & Light offered use of J.M. Stuart Station`s Unit No. 4 as the host site. It was equipped with 24, two-nozzle cell burners arranged in an opposed wall configuration. To reduce NO{sub x} emissions, the LNCB{trademark} has been designed to delay the mixing of the fuel and combustion air. The delayed mixing, or staged combustion, reduces the high temperatures normally generated in the flame of a standard cell burner. A key design criterion for the burner was accomplishing delayed fuel-air mixing with no pressure part modifications to facilitate a {open_quotes}plug-in{close_quotes} design. The plug-in design reduces material costs and outage time required to complete the retrofit, compared to installing conventional, internally staged low-NO{sub x} burners