Prediction of Pulverized Coal Combustibility by Measuring Chemi-luminescence of Radical Spieces around Tuyere

Abstract

To develop novel technologies for reducing CO₂ emission from ironmaking process, steelmaking companies in Japan are engaging in the national project called COURSE50. In this project, a large amount of H₂ is co-injected into blast furnace (BF) with pulverized coal (PC). In order to clarify how the co-injection affects PC combustibility, PC combustibility should be measured in COURSE50 BF. However, it was difficult to measure PC combustibility in BF without bothering operation. Therefore, we developed the non-contact measurement method for PC combustibility (η_PC) by utilizing chemi-luminescence spectra of PC combustion field in the lab-scale combustion furnace. We also applied the method to the COURSE50 experimental BF to ensure the accuracy of the method. And then we found that;

1) Several chemi-luminescence peaks of hydrocarbon radicals and coal ash were detected in the combustion field of PC. Among these peaks, the peak intensity ratio of OH radicals to CH radicals was most appropriate for deriving the formula for the η_PC estimation.

2) In the result of the measurement in COURSE50 experimental BF, η_PC in the experimental BF that estimated by the formula agreed well with the results in lab-scale combustion furnace. The validity of the method for estimating η_PC was confirmed.