Study On The Variation Of Coke Microstructure With Solution Loss Degree And Reaction Temperature

The national standard method has a single test condition and cannot simulate the gradual solution loss process of coke in blast furnace under variable temperature environment.Therefore,a large thermogravimetric analyzer was used to study the behavior of three different cokes under multiple temperature points and solution loss degree,the variation patterns of drum strength with solution loss degree and reaction temperature were analyzed,and the variation patterns of microstructure with them,revealed the deeper reasons for the variation of macroscopic thermal properties of coke.It was shown that with the deepening of solution loss,the micro-pores merged and penetrated to form large pores,the drum strength gradually decreased,but this variation was not completely linear.Under low temperature(1050 ℃ and 1100 ℃),when the solution loss degree reached 30%,the porosity increased significantly,resulted in a larger decrease of drum strength,while under high temperature(1250 ℃ and 1300 ℃),the reaction tended to surface,the porosity is stable,and the microcrystalline structure was strengthened,resulted in a larger decrease in drum strength at 10% and 20% solution loss degree.When solution loss degree is 10% and 20%,the solution loss reaction mainly generated micropore,which had limited damage to coke strength,and the drum strength gradually decreased due to the influence of thermal stress.At 30% solution loss degree,the microstructure had a greater influence on the solution loss mode,and the effect of the intermediate temperature on the expansion of pores leaded to the reduction of the drum strength,under high temperature,the reaction tended to the surface,while the microcrystalline structure was strengthened,leaded to the increase of the drum strength.Due to the differences in pore structure of three cokes,J1,J2 and J3 cokes reached maximum deterioration in the low,medium and high temperature regions,respectively.In conclusion,exploring the variation patterns of coke microstructure with solution loss is important for understanding the macroscopic solution loss behavior and accurately evaluating the coke quality.Figure 34;Table 19;Reference 53...