辅料及翻抛工艺对干旱地区污泥堆肥C、N动态变化的影响

针对我国西北干旱地区污泥堆肥过程中存在养分损失较大和腐熟度差的问题。采用正交实验的方法开展大型条垛堆肥，研究辅料参数及翻抛工艺对堆肥过程中C和N养分动态变化的影响，并利用Topsis分析筛选最优处理，达到当地污泥堆肥过程中减少养分损失和提高腐熟度的目的。结果表明，当玉米秸秆配比为15%时，全氮损失量最小，为3.67%。硝态氮的质量分数在堆肥阶段呈持续上升的趋势，铵态氮的质量分数在堆肥过程中先增加后减小，在堆肥结束时，堆体硝态氮和铵态氮的质量分数均随着秸秆配比的增加而减小，质量分数分别为0.99 g·kg⁻¹和0.78 g·kg⁻¹。堆体有机质的质量分数随着秸秆配比增加而增加，15%秸秆的有机质的质量分数比10%和5%秸秆的分别增加了10.08%和6.61%；堆肥过程中堆体C/N比整体呈现W型变化趋势，结束时堆体C/N比随秸秆配比增加而减小。种子发芽指数 (GI) 随着秸秆配比增大而增加，当玉米秸秆配比为15%时，种子发芽指数均超过100%。Topsis分析表明，最优条垛式堆肥处理为T7 (15%秸秆配比+5 cm秸秆粒径+常规翻抛) ，是一种适合西北干旱地区的条垛式污泥堆肥方法。本研究结果可为该地区的生活污泥条垛式堆肥提供参考。

Effects of auxiliary materials and turning over technique on dynamic changes of C and N of sludge compost in northwest arid areas

In order to solve the problems of high nutrient loss and poor maturity in sludge composting in arid area of northwest China, a large-scale sludge composting experiment was carried out to study the effects of auxiliary material parameters and turning-over technology on the dynamic changes of C and N nutrients of compost during the composting period, and then Topsis analysis was used to screen the optimal treatment. Results showed that when the ratio of corn straw was 15%, the total nitrogen loss was the smallest, which was 3.67%. The nitrate nitrogen content of compost increased continuously during the composting period, while the ammonium nitrogen content increased first and then decreased. At the end of composting, the content of nitrate nitrogen and ammonium nitrogen decreased with the increase of straw ratio, which were 0.99 g.kg−1 and 0.78 g.kg−1, respectively. The organic matter content of compost increased with the increase of straw ratio, and the organic matter content of 15% straw increased by 10.08% and 6.61% compared with that of 10% and 5% straw respectively. The C/N ratio of compost showed a W-shaped change trend during the composting process and it decreased with the increase of straw ratio at the end. The seed germination index (GI) increased with the increase of straw ratio. When the ratio of corn straw was 15%, the seed germination index exceeded 100%. Topsis analysis showed that the optimum compost treatment was T7 (15% straw ratio+5 cm straw particle size+conventional turning over), which might be a suitable strip-stack composting method for arid areas in northwest China. The results of this study can provide theoretical basis and technical support for sludge window composting in this area.