Hernández T, Masciandaro G, Moreno J I, García C
Department of Soil and Water Conservation and Waste Management, Centro de Edafología y Biología Aplicada del Segura (CEBAS-CSIC), P.O. Box 164, 30100 Espinardo-Murcia, Spain.
Waste Manag. 2006;26(12):1370-6. doi: 10.1016/j.wasman.2005.10.006. Epub 2005 Dec 13.
Changes in the chemical and chemical-structural composition of the organic matter of two different sewage sludges (aerobic and anaerobic) mixed with sawdust (1:1 and 1:3, v/v) during composting were determined by monitoring chemical and microbiological parameters as well as by pyrolysis-gas chromatography. Composting was carried out in periodically turned outdoor piles, which were sampled for analysis 1, 30, 60 and 90 days after the beginning of the composting process. Both volatile organic matter and the water soluble C fraction decreased during composting, indicating that the more labile C fractions are mineralized during the process. Microbial activity as measured by microbial respiration (CO(2) evolved from compost samples during incubation) also decreased with composting, reflecting the more stable character of the resulting compost. No major differences were observed between the four composts studied as regards their chemical-structural characteristics. The acetonitrile, acetic acid and phenol pyrolytic fragment tended to increase with composting. Although the final composts were more aromatic in nature than the starting materials, a low degree of humification was observed in all four composts studied, as determined by their high proportion of polysaccharides and alkyl compounds. For this reason, the relationship between pyrolytic fragments, such as benzene/toluene or benzene+toluene/pyrrol+phenols, which are used as indices of humification for soil organic matter, are not of use for such poorly evolved sludge composts; instead, ratios that involve carbohydrate derivatives and aromatic compounds, such as furfural+acetic/benzene+toluene or acetic/toluene, are more sensitive indices for reflecting the transformations of these materials during composting. Both the chemical and microbiological parameters and pyrolytic analysis provided valuable information concerning the nature of the compost's organic matter and its changes during the composting process.
通过监测化学和微生物参数以及热解气相色谱法，确定了两种不同的污水污泥（好氧和厌氧）与锯末（1:1和1:3，体积比）混合后在堆肥过程中有机物的化学和化学结构组成的变化。堆肥在户外定期翻动的堆垛中进行，在堆肥过程开始后的第1、30、60和90天对其进行采样分析。堆肥过程中挥发性有机物和水溶性碳组分均减少，表明在该过程中更不稳定的碳组分被矿化。通过微生物呼吸作用（堆肥样品在培养过程中释放的二氧化碳）测定的微生物活性也随着堆肥而降低，这反映了最终堆肥更稳定的特性。在所研究的四种堆肥的化学结构特征方面未观察到重大差异。乙腈、乙酸和苯酚的热解碎片倾向于随着堆肥而增加。尽管最终堆肥在性质上比原料更具芳香性，但在所研究的所有四种堆肥中均观察到低程度的腐殖化，这是由它们高比例的多糖和烷基化合物所决定的。因此，用作土壤有机质腐殖化指标的热解碎片之间的关系，如苯/甲苯或苯+甲苯/吡咯+酚，对于这种演化程度较低的污泥堆肥并不适用；相反，涉及碳水化合物衍生物和芳香化合物的比率，如糠醛+乙酸/苯+甲苯或乙酸/甲苯，是反映这些材料在堆肥过程中转化的更敏感指标。化学和微生物参数以及热解分析都提供了有关堆肥有机物性质及其在堆肥过程中变化的有价值信息。
