易利用碳的添加对厨余堆肥氮素转化与氮素损失的影响

目的]探讨添加不同量易利用碳（蔗糖）条件下,厨余垃圾堆肥的氨挥发及各形态氮的转化规律和氮损失量。方法]堆肥化试验采用静态好氧工艺,堆体通风量为0.03 m^3/（kg·h）。堆肥设T0、T1、T2 3个处理,其对应的厨余与易利用碳的干基比分别为1.0∶0,1.0∶0.2和1.0∶0.5。结果]堆肥过程中,堆肥T0、T1、T2的厨余氨氮总释放率分别为8.50、8.28、0 g/kg。堆制后,与各堆肥的初始值相比,T0、T1堆体全氮含量分别下降17.1%、10.2%,而T2堆体上升6.7%;有机氮含量分别下降24.5%、23.2%和5.3%;堆肥T0、T1、T2的氨氮浓度分别提高69.4%、761.7%和2 057.7%。堆肥T0、T1、T2的氮损失率分别为35.4%、42.1%和38.1%,氨挥发占氮损失的比例分别为69.2%、58.3%和0%;堆肥T0、T1氮损失的途径主要是氨挥发,而堆肥T2的氮损失绝大部分来自有机氮。结论]在厨余堆肥过程中加入易利用碳,降低了堆肥氨挥发,增加了堆制后堆肥的全氮含量,但并没有减少堆肥氮损失。

Effects of Available Carbon on Turnover and Loss of Nitrogenous Compounds during Composting of Food Wastes

Objective] The rule about ammonia volatilization,nitrogen compounds turnover and nitrogen loss amount during the composting of food wastes were investigated.Method] The ventilation was 0.03 m3/(kg·h).Dry mass ratio of food wastes to available carbon was different.Three kinds of ratio(defined as T0,T1 and T2) were used and they were 1.0∶0,1.0∶0.2 and 1.0∶0.5,respectively.Result] At the end of composting,the accumulative amount of ammonia emissions from food wastes of the three experimentations as T0,T1 and T2 was 8.50,8.28 and 0 g/kg,respectively.The concentration of total nitrogen of T0,T1 decreased by 17.1%,10.2%,while that of T2 increase by 6.7%.Organic nitrogenous content decreased by 24.5%,23.2% and 5.3%.Ammonia concentration increased by 69.4%,761.7%and 2 057.7% in treatment T0,T1 and T2.The lost amount of nitrogen was 35.4%,42.1% and 38.1% of the initial total nitrogen amount.Ammonia volatilization was account for 69.2%,58.3% and 0% of the total nitrogen losses.In treatment T0 and T1 the nitrogen losses of food wastes composting were attributed mostly to ammonia volatilization,and in treatment T2 they were attributed mostly to organic compound directly volatilization.Conclusion] Available carbon reduced the ammonia volatilization during the composting of food wastes,increased the total nitrogen content of composting material,but didn't reduce nitrogen losses.