辅料配比及通风速率对污泥气流膜堆肥过程氮素迁移的影响

Effects of the additive ratio and aeration rate on sludge composting with airflow film

为探究污泥堆肥演变规律并优化污泥气流膜堆肥工艺参数,以园林垃圾和玉米秸秆作为辅料,通过对堆肥过程中的理化指标及可溶性有机物的三维荧光光谱等进行分析,分别研究了3种不同辅料配比、3档通风速率对气流膜堆肥过程氮素变化的影响。结果表明:与其他堆体相比,在辅料配比为7∶3∶1(污泥∶园林垃圾∶玉米秸秆)、通气速率为0.9 m^(3)·h^(-1)的条件下,堆体总氮含量相对上升了9.65%,腐植酸类物质的荧光强度相对百分含量增加了76.62%,此条件下堆体内氮素向稳定的可利用含氮物质中迁移最多,堆肥效果最佳。研究表明,辅料添加量越大,高温阶段持续越长,无害化处理效果越好,但腐熟效果不佳;通风速率对堆肥过程中氮素的稳定化转移影响较大,合适的通风速率能使氮素向有利的方向迁移。

To explore and optimize the process parameters of airflow film composting of sludge,garden waste and maize stalks were used as additives,and through the analysis of the physicochemical indicators during the composting process and the three-dimensional fluorescence spectra of dissolved organic matter,the effects of three levels of aeration rate on nitrogen changes under three different additive ratios were studied.Compared with other piles,when the ratio of additive was 7∶3∶1(sludge∶garden waste∶maize stalks),and the aeration rate was 0.9 m^(3)·h^(-1),the total nitrogen content of the pile increased by 9.65%.The relative fluorescence intensity of humic acid substances increased by 76.62%.Under these conditions,the nitrogen migrated most to the stable and available nitrogen-containing substances,and demonstrated the best composting effect.This study showed that the larger the quantity of additives added,the longer the high-temperature phase was maintained,and the better the harmless treatment effect,although the maturity effect was poorer.The aeration rate has greater impact on the stable transfer of nitrogen during the composting,and proper aeration rate can lead nitrogen transfer in a favorable direction.