湿污泥低温热风干化特性及其数值模拟分析

Drying Characteristics and Numerical Simulation Analysis of Wet SewageSludge Under Low Temperature Hot Air

污泥干化是其终端处置和资源化利用前必要的预处理环节。热风干化是湿污泥常用的处理技术,对污泥热风干化过程中传热传质特性进行深入研究,有助于相关干化工艺的研发并促进其工程化应用。依据自行设计的低温热风对流干化试验台,探究了污泥薄层干化过程中的传热传质规律,并分析了热风温度和流速对污泥干化过程中的湿分比、湿分迁移速率和内部平均温度的影响。此外,根据干化过程中污泥内部热量传递的能量方程,运用ANSYS Fluent软件模拟计算出污泥干化过程的特征参数。

Sludge drying is a necessary pre-treatment process before its terminal disposal and resource utilization.Hot air drying is one of common pretreatment technologies for wet sludge.The study on heat and mass transfer characteristics of sludge during hot air drying is helpful to the research and development of relevant drying process and promote its engineering application.In this paper,heat and mass transfer characteristics of thin-layer sludge in the drying process were analyzed based on a self-designed test setup for the low-temperature hot air convection drying.The effects of hot air temperature and flow rate on sludge moisture ratio,wet separation migration rate and temperature in thin layer were studied.In addition,according to the energy equation of heat transfer in sludge during the drying process,the characteristic parameters of sludge drying process were numerically simulated by ANSYS-Fluent software.