热水解-厌氧消化工艺中污泥的触变性分析  

Analysis on thixotropy of sludge in processing of thermal hydrolysis-anaerobic digestion

作　　者：曹秀芹 柴莲莲 王鑫 CAO Xiu-qin;CHAI Lian-lian;WANG Xin(Key Laboratory of Urban Storm Water System and Water Envi­ronment,Ministry of Education,School of Environmental and Energy Engineering,Beijing University of Civil Engineering and Architecture,Beijing 100044,China)

机构地区：[1]北京建筑大学环境与能源工程学院,城市雨水系统与水环境省部共建教育部重点实验室,北京100044

出　　处：《安全与环境学报》2020年第1期264-270,共7页Journal of Safety and Environment

基　　金：北京建筑大学市属高校基本科研业务专项资金资助项目(X18182)。

摘　　要：采用触变动力学系数作为评价指标,通过流变试验研究了热水解-厌氧消化联合工艺中污泥标准化黏度和触变性的变化规律,并探讨了屈服应力和触变性二者间的联系,从触变性角度为热水解-厌氧消化污泥的处理处置提供参考依据。结果表明:与滞后环相比,用触变动力学系数K更适合表征污泥的触变性;调配污泥、热水解污泥和厌氧消化污泥的标准化黏度均随时间增大逐渐减小;3种污泥的触变性随TSS质量分数增大而减小,经热水解-厌氧消化后污泥的触变性增大,流动性增强;污泥屈服应力越大,触变性越小,稳定性越强。The present paper is aimed at making an investigation of the variation of the normalized viscosity and thixotropy of the sludge in the integrated process of the thermal hydrolysis and mesophilic anaerobic digestion through the rheological experiments.And,then,there comes the need to discuss the relationship between the yield stress and thixotropyby using the thixotropic kinetic coefficient as the evaluation indicator of the sludge thixotropy.The purpose of the discussion is to provide a reference for the treatment and disposal of the thermal hydrolysis-anaerobic digestion sludge from the perspective of thixotropy.The results of our discussion indicate that the hysteresis loop area method fails to reflect the respective dynamic features of the process of the rupture and reconstruction of the sludge flock,for there exist indeed some inconvenience and limitations in the exploitation of the hysteresis ring area to compare the thixotropy of the sludge samples in different types and different ranges of shearing rates.Nevertheless,the thixotropic kinetic coefficient method can help to define the change of the structural parameters with time as the dynamic coefficient of the structural decomposition and reconstruction.The application of the thixotropic kinetic coefficient to specifying the thixotropy of sludge can better reflect the dynamic process of the internal structure.Besides,the normalized viscosity of the mixture,the thermal hydrolysis and the anaerobic digestion sludge tend to decrease gradually with time,whereas the normalized viscosity can decrease sharply in the initial stage of shearing,and then the viscosity gets to be stable slowly and eventually.The K value of the 3 kinds of sludge tends to increase with the increase of TSS,that is,the thixotropy may decrease with the increase of TSS,signifying that it is easier for the sludge to reach a stable state under the action of the external force.As a result of the thermal hydrolysis-anaerobic digestion,the internal structural strength of the sludge tends to be r

关 键 词：环境工程学 触变动力学系数 标准化黏度 触变性 屈服应力 流动性 

分 类 号：X705[环境科学与工程—环境工程]