Application of Orthogonal Array Tests Method to Optimize Operating Conditions for Iron Ore Sintering

The objective of this study was to determine optimal operation parameters for increasing iron ore sinter productivity (SP) and sinter strength (SS) during sintering process by using the orthogonal array test method, and examine their emissions. Three operating parameters, including the water content (Wc; range=6.0–7.0 mass%), suction pressure (Ps; range=1000–1400 mmH2O), and bed height (Hb; rang=500–600 mm) were selected for conducting experiments in a pilot-scale sinter pot to simulate various sintering operating conditions of a real scale-sinter plant. We found the resultant optimal combination (Wc=7.0 mass%, Ps=1400 mmH2O, and Hb=500 mm) could increase SP up to 20.2% in comparison with the current operating condition of a real-scale sinter plant (Wc=6.5 mass%, Ps=1200 mmH2O, and Hb=550 mm). The results of the ANOVA analysis indicates that Wc and Ps were the two significant parameters (p<0.05) accounting for 50.3% and 36.7% of the total contribution of the three selected parameters, respectively. The SS of the resultant optimal combination shows no significant difference (only increased 2.2%) as compared with the current operating condition of the selected real-scale sinter plant. By examining the emissions of SOx, NOx, and particulate matters, the values obtained from the optimal combination were quite comparable to those of the current operating condition. The above results further confirm the applicability of the obtained optimal combination for the real-scale sinter production.