摘要
干化处理是促进污泥减量的有效手段,低温干化技术以耗能低、污染小的优势在污泥处理领域中备受关注。文中通过试验探究了污泥干化过程中比体积和孔隙率的变化情况,由此建立数学模型开展污泥干化的数值模拟。此外,对污泥干化特征进行了描述,对污泥干化的影响因素进行了研究,并讨论了污泥在实际干化过程中的翻抛情况。结果显示,考虑了体积收缩后的模拟结果更接近真实情况,污泥干化的影响因素诸如污泥含水率、太阳辐射强度以及空气湿度对污泥干化速率有显著的影响,空气温度和风速的影响相对较小。干化条件直接影响污泥的含水率分布,干化剧烈时,污泥含水率分布不均匀,出现“蒸发前沿”现象;而干化缓慢时,污泥含水率分布均匀。含水率分布决定污泥翻抛频次,含水率分布越不均匀,翻抛对干化的效果越明显。
Drying treatment can effectively reduce the amount of sludge,and low-temperature drying technology has attracted much attention in the field of sludge treatment with the advantages of low energy consumption and low pollution.The changes of specific volume and porosity during sludge drying were investigated through experiments,and a mathematical model was established to carry out numerical simulation of sludge drying.In this paper,the drying characteristics in the sludge drying process were described,the influencing factors of sludge drying were studied,and the flipping situation of sludge in the actual drying process was discussed.The results showed that the simulation results after considering the volume shrinkage were closer to the real situation,and the influencing factors of sludge drying such as moisture content,solar radiation intensity and humidity had a significant effect,while the influence of wind speed and temperature was relative small.The drying conditions directly affected the moisture content distribution of the sludge.When the drying was violent,the moisture distribution of the sludge was uneven and the phenomenon of"evaporation front"appears,while moisture of the sludge was evenly distributed when the drying rate was small.The distribution of moisture determines the frequency of sludge flipping.The more uneven moisture distribution was,the more obvious the effect of flipping on drying was.
作者
吴文庆
杨航
方宁
梅晓洁
WU Wenqing;YANG Hang;FANG Ning;MEI Xiaojie(Shanghai Investigation,Design&Research Institute Co.,Ltd.,Shanghai 200335,China;National Engineering Research Center of Eco-Environment Protection of Yangtze River Economic Belt,China Three Gorges Corporation,Wuhan 430000,China)
出处
《净水技术》
CAS
2024年第5期109-117,共9页
Water Purification Technology
基金
国家重点研发计划项目(2020YFC1908705)
中国长江三峡集团有限公司科研项目(NBWL202300014)
三峡上海院科标业项目[2022HJ(83)-010]
三峡上海院博士后项目[2022QT(831)-005]
关键词
污泥低温干化
数值模拟
影响因素
干化特征
含水率分布
low temperature sludge drying
numerical simulation
influence factor
drying characteristics
moisture content distribution
