Hot Airflow Ignition with Microwave Heating for Iron Ore Sintering

At present coal gas with high calorific value is used in ignition (CGI) of iron ore sintering, which brings about problems of high energy consumption and environmental pollution. In this paper, the ignition model using microwave heating (MHI) was developed. Took raw materials of a domestic sintering plant as sample, model calculations showed that the minimum ignition temperature was 638.54 degrees C and the energy consumption was 42.03 MJ/m(2) for MHI process in ignition time of 1.5 min. According to the sintering experiments, with ignition at 660 degrees C for 1.5 min the main indexes of sinter qualities and production in MHI were better than those of CGI (1 050 degrees C) process. And the ignition energy consumption (IEC) in MHI was 43.77 MJ/m(2), which was far less than 185.13 MJ/m(2) of CGI. Results also show other advantages of sufficient combustion of coke, better mineralized sinter and less polluted flue gas in MHI process.