针对水热反应处置固体废弃物的亚临界水热环境,综述了水介质和碱作用的研究进展。水介质是水热反应中不可或缺的介质环境和反应载体,在亚临界水热处置固体废弃物体系中,水介质的离子积随温度的升高、压力的增加而急剧增大;水介质压强与填充度的关系不显著;水介质密度随压力变化不明显,主要由温度控制;水介质与产物的相关关系,符合水热反应“生长基元”模型。碱的引入,不但可以提高固体废弃物在水热溶液中的溶解度,且提高了其溶解度温度系数;不同阳离子及碱浓度均会对反应进程和反应产物产生重要影响。亚临界水热反应中水介质和碱的作用是固体废弃物水热反应的基础,对提高固体废弃物水热资源化的效果及进程具有重要作用。
For energy saving, waste utilization and environmental protection, development on effects of aqueous medium and alkali on the disposal of solid wastes via the subcritical hydrotherrnal reaction was reviewed. The aqueous medium is the indispensable media environment and reaction carrier in the hydrothermal reaction. The ion product of aqueous medium increases with increasing temperature and pressure under the subcritical hydrothermal condition. There is no significant relationship between pressure and degree of filling aqueous medium. The density of aqueous medium changes with temperature rather than pressure. The correlation between the aqueous medium and the product follows a so-called "growth units" model of hydrothermal reaction. Alkali can improve the solubility of solid waste in the hydrothermal solution and increase the temperature coefficient of solubility. The cationic type and alkali concentration both have important impacts on the progress of the reaction and the reaction products. The aqueous medium and alkali are the basis of hydrothermal reaction of solid wastes under the subcritical hydrothermal condition, which have a positive effect on the improvement of the reclamation process of solid waste under the hydrothermal condition.