OCR Text |
Show chemical species (see Table I). Extractive gas sample probes employing either aerodynamic or gas quench methods are used to collect gas samples from the LECTR facility. These samples are transported to the analyzer room via heated sample lines to prevent water condensation in the transfer lines. METC also has extensive capabilities for performing non intrusive measurements to characterize flow fields and species concentration profiles. Optical access ports are available in the combustor test sections for application of advanced optical diagnostics as needed. Combustion tests can be conducted using either natural gas or simulated coal-derived low heating value gas mixtures at scales ranging from 0.03 to 3 MWt (0.1 to 10 MM Btu/h) and pressures exceeding 3 MPa (30 atmospheres) . A bottled gas mixing system capable of independent heating and flow control to prepare mixtures of H2, CH4, CO, C02, N2, steam and NH3 is incorporated into the LECTR facility. This gas mixing system can be used for simulating combustor fuel gases typical of IGCC or Advanced PFBC applications at scales up to 60 kWt. In the fall of 1994, METC's SYNGAS generator is scheduled to come on line at which time the LECTR facility will be capable of operation on low heating value fuels at scales up to 2 MWt. The SYNGAS generator consists of a staged (stoichiometric-rich) natural gas combustor, a bottled gas mixing system, and a product gas cooling section. The proposed design will provide fuel gas compositions simulating the range of coal derived fuel gases anticipated from IGCC and PFBC applications. Target ranges for the SYNGAS generator are provided in Table 2. SYNGAS delivery temperatures range from 425 to 810 C at pressures up to 4.3 MPa (600 psig). The facility also has the capability of adding from 0 to 1 percent NH3 to the SYNGAS mixture to simulate the fuel bound nitrogen species typically found in coal derived fuel gas streams. Computational Fluid Dynamics (CFD) codes such as FLUENT and PCGC-3 are available at METC and are being applied for simulation of flowfields, temperature, pressure and chemical species distribution for proposed combustor/burner designs; evaluation of effects of design modifications on NOx and CO emissions; and comparison with experimental results. In addition, reduced (simplified) chemical NOx formation mechanisms are being evaluated for inclusion in the CFD codes to improve NOx formation predictive capabilities. SUMMARY Construction of the LECTR facility is scheduled for completion in January of 1994 with initial combustion tests beginning shortly thereafter. At present, a cooperative research effort is planned 4 1-5 |