三种干燥方式对粪污厌氧残余物化学性质的影响

The effects of three kinds of drying methods on the chemical properties of fecal anaerobic residues

为揭示干燥方式对粪污厌氧残余物化学性质的影响,开展了真空冷冻干燥、风干干燥和热风干燥对粪污p H值、氨氮、总氮、含盐量、总有机碳和溶解性有机碳的影响,对客观认识粪污理化性质和粪污厌氧残余物干燥方式的优选提供依据。研究结果显示真空冷冻干燥处理方式各化学指标相比于风干干燥和热风干燥方式数值较大,表明真空冷冻干燥处理过程能够维持粪污厌氧残余物化学形态和较高的含量。在此基础上,比较发现真空预冻3 h和预冻6 h对各化学指标的影响差异不显著。建议真空冷冻干燥并且预冻3 h作为粪污厌氧残余物相对较适宜的干燥方式,不仅能够较少地破坏粪污化学性质,同时具有操作简便、节省时间等优点。

This study was used to reveal the effects of different drying methods on the chemical properties of fecal anaerobic residues, which provided the theoretical basis for choosing suitable drying measures. After fecal anaerobic residues were dried by vacuum freeze-drying, air- drying, and hot air-drying, a series of evaluation indices was tested, which included pH value, ammonia nitrogen, total nitrogen, total salini- ty, total organic earbon（TOC）, and dissolved organic carbon（DOC ）. The results showed that vacuum freeze-drying had the least loss of chemical components of the three methods, which indicated that the vacuum freeze-drying process could maintain high physical and chemi- cal properties. In this study, the effects of different pre-freezing times on the chemical properties of fecal anaerobic residue were also ana- lyzed. There was no significant difference between 3 hours of freeze-drying and 6 hours of freeze-drying in the characterizations of the fecal anaerobic residues. Thus, freeze-drying for 3 hours is suggested as the best pretreatment because of its easy operation and short time.