添加钙基膨润土对猪粪堆肥中水溶性有机物光谱特征的影响

为了探究添加钙基膨润土(CB)对猪粪好氧堆肥过程中水溶性有机物(DOC)动态变化的影响，向猪粪和木屑混合物料中添加不同质量比的CB，采用自制的强制通风好氧发酵装置，进行了为期60天的好氧堆肥试验。定期采集堆肥样品并进行冷冻干燥，通过紫外-可见光谱(UV-Vis)，傅里叶变换红外光谱(FTIR)和荧光光谱(FS)相结合的方法，对堆肥样品中DOC光谱特征的变化进行研究。结果表明，在堆肥过程中DOC呈降低趋势，且随着CB添加量的增多，DOC的降解率为49.11%~62.92%；堆肥DOC相应的UV-Vis和FS光谱分析显示，类腐殖质的特征峰强度不断升高，而碳水化合物、类蛋白的特征峰强度逐渐降低；且与对照相比，添加钙基膨润土使类腐殖质特征峰的强度增大，峰位置红移。堆肥结束时，相较于对照，添加CB处理的光谱特征参数SUVA₂₅₄，SUVA₂₈₀和腐殖化系数分别增加了16.51%~47.72%，8.58%~44.02%和23.16%~88.22%，且5%添加比例最佳，这被FTIR解析峰密度进一步证实；相关性分析显示，SUVA₂₅₄与堆肥腐熟度呈极显著相关，可指示堆肥腐熟度。综上所述，随着堆肥的进行，有机物由非腐殖质向腐殖质转化，DOC的分子质量及芳构化程度逐渐增加，且添加CB对这一过程具有促进作用，并以5%添加比例最佳。

The Effect of Ca-Bentonite on Spectra of Dissolved Organic Matter during Pig Manure Composting

The aim of this study is to investigate the effect of Ca-bentonite (CB) on organic matter transformation during pig manure (PM) composting. In this paper, five treatments representing different CB concentrations(0%CB，2.5%CB，5%CB，7.5%CB and 10%CB of dry PM weight basis) were mixed with initial feed stock composting system. Moreover, various spectroscopic approaches like UV-Vis spectra, fluorescencespectra (FS) and FTIR were used to characterize the evolution of water-extractable organic matter transformation during PM composting. In addition, on the basis of spectroscopic characterization, multivariate statistical analysis was performed to investigate the correction among the different parameters related to organic matter transformation. The results showed that the concentration of DOC decreased along with the increase of CB dosage during the PM composting, and among all the treatments the degradation rate of DOC concentration was 49.11%~62.92%. Meanwhile, it was observed from spectra results that the peak intensity of humic substance increased and the position was red shift during composting. As compost ended, the SUVA₂₅₄, SUVA₂₈₀ and the amount of increase related to humification coefficient (λ) of all treatments were higher than control, the amount of increase were 16.51%~47.72%，8.58%~44.02% and 23.16%~88.22% in order, and the maximum was observed in 5%CB applied treatment. And FTIR spectra revealed the same result. The correlation analysis showed that SUVA₂₅₄ reflected the change of compost maturity best in all spectral parameters studied in this paper. Overall, the results indicated that adding 5%CB considerably enhanced the organic matter degradation and the humification during PM composting.