OCR Text |
Show 4.2 Data Base for Quantitative Evaluation. About 40 experiments have been carried out with the slurries of which about half were essentially qualitative development experiments investigating the performance of the atomizers and the burner/atomizer combinations. Most of slurry //l was used in these development experiments; firing and performance data were obtained during most of these experiments, but the data were found to be incomplete on account of various instrument errors or malfunctions. Complet data were obtained on 19 runs. Table 3 lists the slurry type and firing data of these experiments; they are listed in the order of execution. The 7 columns are, respectively: the run number, slurry type, nozzle type, slurry firing rate in thermal units, gas rate in thermal units, total therma input, and ratio of gas to total thermal input; the final column shows that the ratio range was 0 to 50%. Associated data included: temperature rise in the 30 water tubes (and the water flow rate), POC temperature and composition (CO , CO, and 0?), main and atomizing air rate, roof temperatures, and NOX and SOX values in the POC for about half these runs. Treatment of the data focused on reduction of the measurements to permit construction of the main furnace performance curves - the firing curve and thermal efficiency. The thermal input rates (H ) as listed in Table 3 were determined from the flow rates and heats of combustion of the listed fuels. Ostwald equations were used to check the consistency of the POC composition to determine the excess air, to cross-check the excess air values calculated from the input fuel and air rate data, and hence provide the POC mass flow rate. The gas analysis was used to determine the mass fraction of each constituent which, with the specific enthalpies from the gas temperature, yielded the POC enthalpy rate, H . The thermal output in the water tubes was calculated from the temperature rise and water flow rate |