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研究了在１２２３～１４７３Ｋ的氮气氛中３种不同挥发分煤粉的粒度、铁精矿粉粒度、温度及碳—氧摩尔比对含煤球团还原速度的影响。发现降低煤粉或铁精矿粉粒度，提高温度或碳—氧摩尔比可提高含煤球团的还原速度，且这４种因素对还原速度的影响程度随煤种挥发分的降低而增大。分别采用以碳气化反应、气相内扩散、界面反应为控制环节而得出的表达含煤球团反应过程的速度方程处理本研究数据，发现３种速度方程（４种表达形式）均能较好地与本研究数据吻合。比较由不同速度方程计算出的速度常数而得出的含煤球团的活化能，发现对含３种不同挥发分煤的球团，以气相内扩散为控制环节的活化能均较以碳气化反应或界面反应为控制环节的活化能大，由此可推断含煤球团还原过程应由气相内扩散控制。含高挥发分煤的球团的气相内扩散活化能较含低挥发分煤的球团的活化能低，可推断前者的还原速度较快。
The effects of particle size, iron ore concentrate particle size, temperature and carbon-oxygen molar ratio on the reduction rate of coal-bearing pellets were investigated in a nitrogen atmosphere of 1223-1473K. It was found that reducing the particle size of pulverized coal or iron ore concentrate and increasing the temperature or the molar ratio of carbon to oxygen increased the reduction rate of coal-bearing pellets. The influence of these four factors on the reduction rate increased with the decrease of coal volatile. The velocity equations for the reaction of coal-bearing pellets, which are derived from carbonization reaction, diffusion in gas phase and interfacial reaction, respectively, are used to deal with the data of this study. The results show that all three velocity equations (four kinds of expression) The data match this study. Comparing the activation energy of coal-bearing pellets obtained from the velocity constants calculated from different velocity equations, it is found that for the pellets containing three kinds of volatile coal, the activation energies of gas-phase diffusion as the control are all higher than those of carbon gasification Reaction or interface reaction for the control of the activation energy, which can be concluded that the reduction of coal-bearing pellets should be controlled by diffusion within the gas phase. The gasification diffusion activation energy of the pellets containing high volatile coal is lower than the activation energy of the pellets containing low volatile coal, and the reduction speed of the former can be deduced.