The aim of this paper was to investigate the characterized hydrochar of maize straw prepared via the hydrothermal carbonization (HTC) process as a solid fuel for blast furnace injection. The effect of HTC conditions on the yield, physicochemical properties and combustion reactivity of hydrochar were evaluated by varying the HTC temperature over the range of 220–340 °C and the HTC time over the range of 15–120 min. The results showed that with the increase in HTC temperature and time, the yields, H/C and O/C values of hydrochar decreased, and the higher heating value increased. These characteristic changes in hydrochar are similar to those in bituminous coal because of dehydration and decarboxylation. The physicochemical properties and structure analyses showed that the specific surface area increased first and then decreased; meanwhile, the CC, CO and aromatic functional groups gradually increased. The carbonaceous structure of hydrochar became more compact, orderly and stable. Compared to the feedstock of maize straw, the combustion of hydrochar was expected to have higher ignition energy and become more stable with its higher ordering degree of the carbonaceous structure. HTC could be used as an effective method to convert maize straw biomass to a high quality solid injection fuel for the blast furnace.

本文的目的是研究通过水热碳化（HTC）工艺制备的玉米秸秆的特征碳氢化合物，将其作为高炉注入的固体燃料。通过改变220-340°C范围内的HTC温度和15-120分钟范围内的HTC时间来评估HTC条件对水焦炭收率，理化性质和燃烧反应性的影响。结果表明，随着HTC温度和时间的增加，水焦炭的收率，H / C和O / C值降低，较高的热值增加。由于脱水和脱羧作用，水煤的这些特征变化与烟煤的特征变化相似。理化性质和结构分析表明，比表面积先增大后减小。同时，CC，C O和芳族官能团逐渐增加。水焦炭的碳质结构变得更致密，有序和稳定。与玉米秸秆的原料相比，预期碳氢化合物的燃烧具有更高的着火能量，并且由于碳质结构的有序度更高而变得更加稳定。HTC可以用作将玉米秸秆生物质转化为高炉用高质量固体喷射燃料的有效方法。