花卉废物和牛粪联合堆肥中的氮迁移

以花卉废物和牛粪为原料,进行了温度反馈的通气量控制联合堆肥中的氮迁移中试研究.采用自制的静态好氧床进行一次发酵,过程控制采用温度反馈通气量控制方法,发酵周期20d;采用周期性翻堆进行物料二次腐熟,腐熟周期40d.研究了堆肥过程中总氮、有机氮、无机氮、氨氮、硝氮等氮素形态转化随时间的变化特征及温度反馈的通气量控制对氮迁移的影响.结果表明:堆肥初期的氨化作用和反硝化作用显著,氮素总量损失累计达41.98%,其中主要是有机氮的损失,99.95%的氮损失发生在一次发酵阶段;氮素损失主要是在pH和温度较高条件下的氨气大量挥发造成的.对通风进行有效控制、提高物料C/N及添加酸性物质有望减少N损失.对于C/N较低,硝态氮含量较高的物料堆肥,NH₄⁺-N≤0.04%、NH₄/NO₃≤0.16不能作为腐熟度指标.

Nitrogen Transformation During Co-composting of Flower Wastes and Cattle Manure

Nitrogen transformation during co-composting of flower wastes and cattle manure were studied in pilot scale. The first stage was aerobic static bed of composting based on temperature feedback and control via aeration rate regulation, which lasted about 20d. The second stage was window composting, with a period of about 40d. Changes of composting of total nitrogen (TN), organic nitrogen, inorganic nitrogen, NH4(+)-N and NO3(-)-N were studied. Results show that ammoniation and denitrifcation were serious at the beginning of first stage. The total nitrogen losses was about 41.98% during 60 days of composting, most of which was losses of organic nitrogen contributing about 99.95% at first stage. Losses of N were governed mainly by volatilization of ammonia as the pile temperatures and pH values were high. It is hoping to reduce nitrogen losses by effective aeration rate regulation, improving C/N of raw materials and addition of acidic amendment. On the part of material of low C/N and high nitrate, it is not appropriate for NH4(+)-N < or = 0.04% and NH4/NO3 < or = 0.16 as maturity indicators.