International Water Management Institute, Africa Regional Office, PMB CT 112, Accra, Ghana.
Water Res. 2009 Oct;43(18):4665-75. doi: 10.1016/j.watres.2009.07.021. Epub 2009 Jul 21.
This paper presents the potentials and performance of combined treatment of faecal sludge (FS) and municipal solid waste (SW) through co-composting. The objectives were to investigate the appropriate SW type, SW/FS mixing ratio and the effect of turning frequency on compost maturity and quality. Solid waste (SW, as market waste, MW, or household waste, HW) was combined with dewatered FS in mixing ratios of 2:1 and 3:1 by volume and aerobically composted for 90 days. Four composting cycles were monitored and characterised to establish appropriate SW type and mixing ratio. Another set of five composting cycles were monitored to test two different turning frequencies: (i) once in 3-4 days during the thermophilic phase and 10 days during maturation phase and (ii) once in every 10 days throughout the composting period. Samples were taken at every turning and analysed for total solids (TS), total volatile solids (TVS), total organic carbon (TOC), electrical conductivity (EC), pH, ammonium and nitrate nitrogen (NH(4)-N and NO(3)-N) and total Kjeldahl nitrogen (TKN). Temperature, C/N ratio, NO(3)-N/NH(4)-N ratio and cress planting trials were chosen as maturity indicators. Result showed a preference of MW over HW and mixing ratio of 2:1 over 3:1. There was no significant effect of different turning frequencies on the temperature changes and the quality of mature compost. The final product contained C/N ratio of 13 and NO(3)/NH(4)-ratio of about 7.8, while TVS was about 21% TS and the NH(4)-N content was reduced to 0.01%. A co-composting duration of 12 weeks was indicated by the cress test to achieve a mature and stable product. The turning frequency of 10 days is recommended as it saves labour and still reaches safe compost with fairly high nutrient content.
本文提出了通过混合堆肥联合处理粪便污泥（FS）和城市固体废物（SW）的潜力和性能。目的是研究合适的 SW 类型、SW/FS 混合比以及翻堆频率对堆肥成熟度和质量的影响。固体废物（SW，如市场废物、MW 或家庭废物、HW）与脱水 FS 以体积比 2:1 和 3:1 混合，并进行有氧堆肥 90 天。监测并描述了四个堆肥周期，以确定合适的 SW 类型和混合比。另外进行了五个堆肥周期的监测，以测试两种不同的翻堆频率：（i）在高温期每隔 3-4 天翻堆一次，在成熟期每隔 10 天翻堆一次；（ii）在整个堆肥期每隔 10 天翻堆一次。在每次翻堆时取样，并分析总固体（TS）、总挥发性固体（TVS）、总有机碳（TOC）、电导率（EC）、pH 值、铵态氮和硝态氮（NH4-N 和 NO3-N）以及总凯氏氮（TKN）。温度、C/N 比、NO3-N/NH4-N 比和芥菜种植试验被选为成熟度指标。结果表明，MW 优于 HW，2:1 的混合比优于 3:1。不同翻堆频率对温度变化和成熟堆肥质量没有显著影响。最终产品的 C/N 比为 13，NO3-N/NH4-N 比约为 7.8，TVS 约为 TS 的 21%，NH4-N 含量降低至 0.01%。芥菜试验表明，12 周的共堆肥时间可达到成熟稳定的产品。建议采用 10 天的翻堆频率，因为它可以节省劳动力，并且仍能达到具有较高养分含量的安全堆肥。
