Research and Application of Sintering Surface Steam Spraying Technology for Energy Saving and Quality Improvement

Abstract

Spraying technology on sintering surface bed after ignition has become a hot research topic, with the purpose of achieving energy-saving, emission reduction and improvement of sintering indexes. In this paper spraying steam technology was researched from theory, experiment and practice. First of all, from the thermodynamic and kinetic analysis, the mechanism of sintering surface spraying steam was analyzed and its advantageous effect was confirmed. Based on this, sintering pot test and commercial trial were carried out respectively. The results shown that spraying steam is beneficial for increasing coke combustion efficiency with improving CO2/(CO+CO2) in the exhaust gas from 80% to about 85% level, through decreasing CO content of flue gas by more than 1000–2000 ppm. There was a suitable spraying amount to improve the quality of the sinter, and the spraying position of the steam cannot be excessively front and rear. Due to the low steam pressure (1 kg) and temperature (about 100 °C) compared with industrial steam (3 kg and 130 °C, respectively), the sinter quality such as yield index was affected by spraying steam in sintering pot test to a certain extent, and proper spraying amount (0.008 m3, 50 kg sinter) in sinter pot test is far smaller than application amount in commercial trial (2t/h). It is thought that suitable spraying steam parameters has a comprehensive effect of energy saving and quality improvement.