温度及时间对污泥和餐厨垃圾保存特性的影响

为确定污泥和餐厨垃圾在不同条件下的保存期限，以夏、冬季取样的污泥和餐厨垃圾为研究对象，考察了其在4、20、和35 ℃条件下自身理化性质随保存时间的变化情况。通过总糖、总蛋白质、NH₃-N、pH和总挥发性脂肪酸(TVFA)等理化指标和乳酸、乙酸等有机酸的变化规律确定其最佳保存期限。结果表明，在污泥保存过程中，总糖、总蛋白质表现为下降趋势，NH₃-N和pH则持续上升，整体表现为随着保存温度的升高，总糖、总蛋白质、NH₃-N和pH的上升和下降趋势更加明显；餐厨垃圾在各保存条件下均出现明显的变质酸化现象，其中，乳酸为最主要有机酸。冬季和夏季取样污泥在4 ℃环境中分别可以保存30 d和15 d；对于餐厨垃圾，冬季取样时可在4 ℃环境中保存1 d，而在其他情况下均达不到理想的保存效果。

Effects of temperature and time on the storage characteristics of sludge and food waste

The aim of this study was to explore the storage time of sludge and kitchen waste under different situations. For the samples of sludge and kitchen waste taken in summer and winter, the variations of their physiochemical properties and storage time at 4, 20 and 35 ℃ were investigated. Several physical or chemical indicators, such as total carbohydrate, total protein, NH3-N, TVFA, and organic acids, such as lactic acid and acetic acid, were employed here to determine the optimal storage period. The results showed that for the sludge, the total carbohydrate and total protein presented a downward trend during the storage process, while NH3-N and pH increased continuously. The overall performance changed sharply with the increase of storage temperature. The kitchen waste showed obvious deterioration and acidification in any case, of which lactic acid was the primary component of organic acid. The sludge samples can be stored in 4 ℃ for 30 days and 15 days in winter and summer, respectively. The kitchen waste sampled in winter could be stored at 4 ℃ for only 1 day, and could not be obtained an ideal storage result at any other cases.