作为厌氧发酵原料的水分选有机垃圾特性分析

对水分选有机垃圾（WSOFMSW）的固体有机部分（SOF）和气浮污泥部分（AFS）进行采样，分析它们的成分及生化特性，并在此基础上进行小试规模（30L）的厌氧发酵产甲烷实验.结果表明：SOF的惰性部分为18%，可降解部分（挥发性固体）为72%，其中，碳水化合物、蛋白质和脂肪分别为40.4%、21.8%和9.8%；AFS的惰性部分为2%，可降解部分为82.4%，其中，碳水化合物、蛋白质和脂肪分别为53.5%、19.2%和9.7%.SOF的金属含量比AFS高，主要金属元素为Ca、Fe、Al、K、Na和Mg.在重金属中，Zn、Mn、Ni、Hg和Cr的含量超过堆肥产品的限制值.WSOFMSW在标准温度和压力（0 ℃ 和1.013×105 Pa ，文中以STP表示）下的理论产甲烷能力为484 m3 ·t-1(以VS计)，实验甲烷产率为273 m3 ·t-1，中试甲烷产率为245 m3 ·t-1，每吨湿WSOFMSW产甲烷32 m3.水分选有机垃圾在厌氧消化过程中不会发生重金属、挥发性脂肪酸和氨氮抑制，但是厌氧消化启动时间较长，需要20 d.

Characterization of water sorted organic fraction of municipal solid waste for anaerobic digestion

The solid organic fraction (SOF) and air-flotation sludge (AFS) from the water sorted organic fraction of municipal solid waste (MSW) were sampled and their composition and biochemical characteristics were analyzed. A pilot-scale (30 L) anaerobic digestion experiment was also carried out. The analysis showed that 18% of SOF was inert fraction, 72% was biodegradable (volatile solids) including 40.4%, 21.8% and 9.8% carbohydrates, proteins and lipids respectively. For AFS, 2% was inert, and 82.4% was biodegradable, including 53.5%, 19.2% and 9.7% carbohydrates, proteins and lipids, respectively. The metal content of SOF was higher than that of AFS. The main metal elements were Ca, Fe, Al, K, Na and Mg. Heavy metal element contents (Zn, Mn, Ni, Hg and Cr) were higher than the limits on compost products. The theoretical methane potential of the water sorter organic fraction of MSW was 484 m3 ·t-1 (based on volatile solids), the experimental methane yield was 273 m3 ·t-1, pilot-scale methane yield was 245 m3 ·t-1. One ton of the wet organic fraction can produce 32 m3 methane. Heavy metals, volatile fatty acids and ammonia inhibition were not found during the whole anaerobic fermentation process, however, a long start-up period of 20 d was necessary.