Department of Civil and Environmental Engineering, University of South Carolina, 300 Main Street, Columbia, SC 29208, United States.
Waste Manag. 2013 Nov;33(11):2478-92. doi: 10.1016/j.wasman.2013.05.025. Epub 2013 Jul 3.
Hydrothermal carbonization (HTC) is a thermal conversion technique that converts food wastes and associated packaging materials to a valuable, energy-rich resource. Food waste collected from local restaurants was carbonized over time at different temperatures (225, 250 and 275°C) and solids concentrations to determine how process conditions influence carbonization product properties and composition. Experiments were also conducted to determine the influence of packaging material on food waste carbonization. Results indicate the majority of initial carbon remains integrated within the solid-phase at the solids concentrations and reaction temperatures evaluated. Initial solids concentration influences carbon distribution because of increased compound solubilization, while changes in reaction temperature imparted little change on carbon distribution. The presence of packaging materials significantly influences the energy content of the recovered solids. As the proportion of packaging materials increase, the energy content of recovered solids decreases because of the low energetic retention associated with the packaging materials. HTC results in net positive energy balances at all conditions, except at a 5% (dry wt.) solids concentration. Carbonization of food waste and associated packaging materials also results in net positive balances, but energy needs for solids post-processing are significant. Advantages associated with carbonization are not fully realized when only evaluating process energetics. A more detailed life cycle assessment is needed for a more complete comparison of processes.
水热碳化（HTC）是一种热转化技术，可将食物垃圾和相关包装材料转化为有价值的、富含能量的资源。从当地餐馆收集的食物垃圾在不同的温度（225、250 和 275°C）和固含量下进行碳化，以确定工艺条件如何影响碳化产品的性质和组成。还进行了实验以确定包装材料对食物垃圾碳化的影响。结果表明，在评估的固含量和反应温度下，大部分初始碳仍保留在固相内。初始固含量会影响碳的分布，因为化合物的溶解度增加，而反应温度的变化对碳的分布影响很小。包装材料的存在会显著影响回收固体的能量含量。随着包装材料比例的增加，由于与包装材料相关的低能量保留，回收固体的能量含量降低。除了在 5%（干重）固含量下，HTC 在所有条件下都产生净正能量平衡。食物垃圾和相关包装材料的碳化也会产生净正平衡，但固体后处理的能量需求很大。仅评估工艺能量时，碳化的优势并未完全实现。需要进行更详细的生命周期评估，以更全面地比较各个工艺。
