Combustion Characteristics of Occidental Coal-Water Mixtures

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measured using continuous gas analyzers. The location of the sample point in the stack and the identification of the gases measured are shown in Figure 1. A summary of gas analysis instrumentation is presented in Table 5. Particulate grain loadings were determined at the boiler discharge using EPA Method 5. Particulate size distributions were also determined at the same location using a Washington State Mark III Impactor. Ash PSD and morphology were also studied by laser light scattering and scanning electron microscopy. Separate carbon samples using the Method 5 filter were also taken for determination of the carbon conversion efficiency. An instack opacity meter was used to provide a qualitative indication of the grain loadings during the various test runs. 3.2 ATOMIZATION FACILITY The spray chamber provides a cold flow section for the spray nozzle and droplet size measurement instrumentation. The chamber has an 18 x 18 inch square cross section, with air and CWM flow in the vertically downward direc­tion, Figure 4. The atomizer was mounted on pipes transporting the fuel and atomizing air which allowed the spray pattern to be traversed in the axial and radial position relative to a fixed measurement position. An induced draft system was used to flow air through the test section and this air flow was controlled with a slide valve. Flow straighteners provided uniform velocity in the measurement section. The optimum air flow velocity was selected experimentally to prevent the backflow of the very small droplets. Atomized slurry was collected at the bottom of the spray chamber. The air was filtered before being processed through a baghouse and exhausted to the atmosphere. Optical access to the spray chamber was provided by holes cut into the plexiglass sides. Holes were used rather than optical windows, since they offered two advantages: (1) helped prevent the accumulation of dried slurry in the optical path and (2) allowed the induced draft through the opening to further prevent CWM collection on the optics. The absence of windows also eliminated the potential errors in measurement that can be introduced by misaligned window locations. 14 KVB72-P327 D194