猪粪好氧堆肥过程中氧气的剖面分布特征

Profile Characteristics of Oxygen Concentration During Aerobic Composting of Pig Manure

采用堆肥氧气专用监测探头,研究了猪粪快速好氧堆肥过程中氧气的剖面分布特征。结果表明,在不同堆肥阶段,通风充氧后堆体各深度氧气浓度都可以恢复到17%以上,下部氧气恢复时间较上部短,恢复后,氧气浓度较上部高。停止通风后,上部氧气浓度的减小速度比中、下部快,减小后氧气浓度较下部低,随着深度的增加,停止通风后氧气浓度的减少趋势逐渐变缓。随着堆肥的进行,各部位通风前的氧气浓度值逐渐升高,高温中期以后,中、下部通风前的氧气浓度可以达到10%以上,氧气浓度的减小趋势也逐渐减缓。

Aerated static composting is one of the best ways to deal with animal wastes. Oxygen is an important factor influencing the composting process. The growth of aerobic microorganism, the composting duration and the quality of compost depend greatly on the oxygen concentration in the composting pile and the oxygen supplying process. In order to control the oxygen concentration and optimize the composting process, it is necessary to study the profile characteristic of oxygen at different stages of composting. The equipment for measuring oxygen concentration of composting pile was used to study the spatial distribution and variation of oxygen in the composting process. The results showed that after ventilation the oxygen concentration could increase to 17% or more at different composting stages, the balance time of oxygen concentration at the bottom part was shorter than that of the upper part. After ventilation, the decrease rate of oxygen concentration of the upper part was faster than that of the middle and bottom of the pile. After same time of stopping ventilation, the oxygen concentration before ventilation increased along with the proceeding of composting. The oxygen concentration before ventilation could be upper 10% at the middle and bottom of the pile after the middle stage of high temperature, and the decrease rate of oxygen concentration declined too.