太阳能温室内污泥主要干燥参数的变化  

CHANGING OF SEWAGE SLUDGE CHARACTERISTICS DURING ITS SOLAR DRYING IN GREENHOUSES

作　　者：赵磊[1] 陈德珍[1] 王中慧[1] 

机构地区：[1]同济大学热能与环境工程研究所,上海200092

出　　处：《太阳能学报》2009年第9期1264-1270,共7页Acta Energiae Solaris Sinica

基　　金：污染控制与资源化研究国家重点实验室开放基金项目(PCRRF06004);同济大学新能源创新基金

摘　　要：研究了污水污泥在利用太阳能温室从约80%含水率干燥至约40%的过程中干燥面积、孔隙率、污泥干缩形变率3个关键结构参数的变化行为,为干燥速率的预测以及太阳能等形式干燥的应用设计奠定基础。污泥在不同季节的太阳能温室内干燥时持续监测温室内外温度、湿度和污泥的水份变化,并记录其表面形貌的变化过程;利用Image-Pro Plus图形分析软件对污泥照片进行面积分析和计算;用压实法测量不同干燥阶段污泥的孔隙率,并结合体积排空法得到不同干燥阶段的干缩形变率。最终获得污泥太阳能温室内干燥过程中表面积、孔隙率、形变率和干燥速率随水分变化的规律。研究结果表明,单纯污泥利用太阳能干燥无辅助热源时,干燥速率不超过0.63kg水/m^2·h,表面积、孔隙率和形变率只与污泥水分相关,与干燥速率没有明显相关性。Sewage sludge drying from moisture content of 80% to around 40% in greenhouse was investigated. During natural solar drying process in greenhouse, temperature and humidity inside and outside the greenhouse as well as moisture of sewage sludge were continuously monitored in three different seasons. Change of sludge surface topography was recorded with a digital camera, and the obtained digital photos were analyzed with help of an Image-Pro Plus software （IPP v6.3） to calculate drying surface area. In order to obtain its porosity the sludge was sampled and then undergone high pressure compaction to demolish its pores and porosity was calculated by volume reduction; at the same time with a parallel sample shrinkage rate during drying was acquired through volume gauging in measuring glass filled with kerosene. Finally the changing curves of surface area vs. moisture content, porosity vs. moisture content, shrinkage rate vs. moisture content, and the drying speed vs. moisture content during different drying processes were obtained. The results showed that solar drying speed of sewage sludge do not exceed 0.63kg water/m^2 · h during experiments in summer, autumn and winter, surface area, porosity and shrinkage rate of sludge are closely related to its moisture content, but have no obvious relationship with dying speed.

关 键 词：污泥 太阳能干燥 面积 孔隙率 形变率 

分 类 号：TK51[动力工程及工程热物理—热能工程]