Dynamic Study Of Coke-CO₂ Gasification Under Isothermal And Non-isothermal Condition

The blast furnace energy consumption accounts for roughly 70% of the iron and steel industry,the establishment of low coke ratio operation technology is very important. This paper will put forward a new index to predict low coke rate.The research of metallurgical reaction kinetics is the reaction speed and reaction mechanism.So,kinetics analysis produces an adequate kinetic description of the process in terms of the reaction model and Arrhenius parameters.These f)(a, E and lnA are called “kinetic three components”.The traditional method of kinetic methodology was fitting experimental data to reaction models, the model fitting approach is expected to produce information about both the mechanism and the kinetic constants of the process.The variation of reaction models（ f）（a or G）（a） indirectly causes the changes of Ea and lnA,giving rise to the uncertainty of the experiment.So, model-free approach appear, which is called isoconversional principle.The isothermal gasification tests and non-isothermal gasification tests of powdered cokes are performed in CO₂ atmosphere using a thermo-gravimetric analyzer,simultaneously.The kinetic parameters are calculated by using reaction models and isoconversional principle,the reaction mechanism is discussed.The isothermal thermogravimetry is applied to the char particles-CO₂ reaction using coke reactivity measurement device. Analyse the reaction process simplely.Eventually reached the following conclusion:1.Coke gasification reaction occurs in heating conditions:Under the same reaction degree, the higher the heating rate is, the higher the temperature of the reaction is;The higher the heating rate is, the higher the temperature of the end of the reaction is;Under the same temperature, the higher the heating rate is, the higher the gasification reaction rate is;the higher the heating rate is,the higher the temperature corresponding to the maximum gasification reaction rate is.2.Coke gasification reaction occurs under the condition of constant temperature heating rate:when reaching to a certain extend,the required time decrease with the increase of temperature, The higher the temperature is, the higher the temperature of the end of the reaction is;the higher the temperature is,the higher the temperature corresponding to the maximum gasification reaction rate is.3.Under the same reaction conditions,ignoring the effect of pore diffusion,theresult of the comparing between the activation energy calculated by the reaction model and the activation energy values which are obtained by the conversion methods is generally equal.4.Coke gasification reaction mechanism is :along with the pore diffusion,the interface reaction exists.5.In the process of the lump coke gasification reaction,the reaction rate generally shows the tendency of reduing after the increasing.6.Considering the lump coke as the combination of multiple diffusion layer,each diffusion layer is composed of coke powder of equal quality, extending the sixth chapter of powdered coke gasification reaction experiment results,when each diffusion layer gasification reaction occurs,the reaction rate generally shows the tendency of reduing after the increasing,the curve of multiple powdered coke gasification reaction rate makes up each set of lump coke gasification reaction experiment results figure.