初始温度对人粪便好氧堆肥过程的影响

温度是好氧堆肥过程中需要控制的一个重要因素。不同的初始温度直接影响了堆肥过程中微生物活性及有机物的降解。为了研究初始温度对粪便好氧堆肥过程的影响,采用序批式好氧堆肥反应器,以新鲜锯末为载体,控制含水率在55%~60%的范围左右并强制通风的好氧条件下,进行了初始温度分别为25、35、45和55℃,20 d为一个周期好氧堆肥实验,研究了不同初始温度条件下堆肥过程有机物降解、氮的迁移转化及种子发芽指数的变化。结果表明,初始的高温度会抑制堆肥反应的进行,但初始温度越高,水解效果越显著;初始的高温有利于COD的去除,最终COD的去除率分别为88.2%、89.3%、92.0%和89.9%。初始高温对种子发芽率有抑制作用,同时延迟了堆肥的腐熟期。

Effect of initial temperature on aerobic composting of human feces

As an important factor, temperature affects the organic decomposition and microbial communities in aerobic composting. A closed aerobic composting reactor was used for feces composting with sawdust as the bulky matrix, the moisture content was maintained at 55%~60%, and air was supplied continuously. Four different temperatures (25℃,35℃,45℃,55℃) were selected as initial temperature. Main attentions were paid on the effect of initial temperature on human feces composting, especially the transformation of nitrogen, degradation of organic matter and variation of germination index. The result indicates that if the initial temperature is too high, the composting process will be inhibited. However, higher initial temperature could promote hydrolysis of organic matter. The higher initial temperature also leads to the lower pH during the initial stage. The initial thermophilic condition is conducive to the removal of COD, the removal rates of COD are 88.2%, 89.3%,92.0%,89.9%,respectively. The final germination indices are more than 100%, which indicate that composting has matured. The initial high temperature inhibits seed germination rate, while maturity period of compost is delayed.