Review of Research on Coke Gasification in the Blast Furnace with Elevated Hydrogen Content and Determination of Coke’s Postreactive Strength. 4. Change in Coke Strength after Gasification in the Presence of H₂O

Previous articles in this series presented thermodynamic analysis of the reactions in the gasification of coke in the presence of H₂O and some parameters of this process in the laboratory. The sample porosity was estimated qualitatively (visually) and quantitatively by means of specialized image analysis software. The coke strength was assessed by the standard method of determining the postreactive strength CSR, introducing corrections as necessary if the sample size and mass were too small. In this final article, those results are discussed. The presence of moisture intensifies gasification, consequently decreasing its hot strength. For gasification by reaction with CO₂, CSR is significantly higher than in the presence of moisture; the difference is proportional to the H₂O content in the gas. In the future, for blast furnaces with a high hydrogen content, the method of determining CSR must be modified to take account of the influence of water vapor (formed in the reaction) on coke gasification.