Gioannis G De, Muntoni A, Cappai G, Milia S
Department of Geoengineering and Environmental Technologies, University of Cagliari, Piazza D'Armi, 09123 Cagliari, Italy.
Waste Manag. 2009 Mar;29(3):1026-34. doi: 10.1016/j.wasman.2008.08.016. Epub 2008 Oct 26.
Mechanical biological treatment (MBT) of residual municipal solid waste (RMSW) was investigated with respect to landfill gas generation. Mechanically treated RMSW was sampled at a full-scale plant and aerobically stabilized for 8 and 15 weeks. Anaerobic tests were performed on the aerobically treated waste (MBTW) in order to estimate the gas generation rate constants (k,y(-1)), the potential gas generation capacity (L(o), Nl/kg) and the amount of gasifiable organic carbon. Experimental results show how MBT allowed for a reduction of the non-methanogenic phase and of the landfill gas generation potential by, respectively, 67% and 83% (8 weeks treatment), 82% and 91% (15 weeks treatment), compared to the raw waste. The amount of gasified organic carbon after 8 weeks and 15 weeks of treatment was equal to 11.01+/-1.25kgC/t(MBTW) and 4.54+/-0.87kgC/t(MBTW), respectively, that is 81% and 93% less than the amount gasified from the raw waste. The values of gas generation rate constants obtained for MBTW anaerobic degradation (0.0347-0.0803y(-1)) resemble those usually reported for the slowly and moderately degradable fractions of raw MSW. Simulations performed using a prediction model support the hypothesis that due to the low production rate, gas production from MBTW landfills is well-suited to a passive management strategy.
针对填埋气产生情况，对剩余城市固体废弃物（RMSW）的机械生物处理（MBT）展开了研究。在一家全尺寸工厂对经过机械处理的RMSW进行采样，并进行8周和15周的好氧稳定化处理。对经过好氧处理的废弃物（MBTW）进行厌氧测试，以估算产气速率常数（k，y⁻¹）、潜在产气能力（Lₒ，Nl/kg）以及可气化有机碳的量。实验结果表明，与原始废弃物相比，MBT分别使非产甲烷阶段和填埋气产生潜力降低了67%和83%（处理8周）、82%和91%（处理15周）。处理8周和15周后，可气化有机碳的量分别为11.01±1.25kgC/t（MBTW）和4.54±0.87kgC/t（MBTW），分别比原始废弃物的气化量少81%和93%。MBTW厌氧降解获得的产气速率常数（0.0347 - 0.0803y⁻¹）值与通常报道的原始城市固体废弃物缓慢和中等可降解部分的值相似。使用预测模型进行的模拟支持了这样的假设，即由于产气速率低，MBTW填埋场的产气非常适合被动管理策略。
