Influence of ultrasonication and Fenton oxidation pre-treatment on rheological characteristics of wastewater sludge
Influence of ultrasonication and Fenton oxidation pre-treatment on rheological characteristics of wastewater sludge
复制标题
DOI：
10.1016/j.ultsonch.2009.06.007
复制
发表时间：
2010-01-01
影响因子：
8.4
通讯作者：
Surampalli, R. Y.
中科院分区：
文献类型：
--
作者：
Pham, T. T. H.;Brar, S. K.;Surampalli, R. Y.
研究了超声波和Fenton氧化作为物化前处理工艺对废水污泥流变学变化的影响。处理前后的污泥表现出剪切稀化的非牛顿流变性和总固体在10g/L~40g/L范围内的触变性，并研究了宾汉塑性、卡森定律、NCA/CMA Casson、IPC糊和幂定律等流变模型。在所有神学模型中，幂定律在描述淤泥的神学方面更为突出。当固体质量浓度为10~40g/L时，污泥的流动特性指数n分别从0.50~0.35、0.62~0.55、0.63~0.58增加，污泥的假塑性降低，污泥的稠度指数K由42.41188、25.6%降至620.4、52.5%~317.9，污泥的生物降解性与脱水性能的改善、粘度的降低以及颗粒大小的变化与污泥前处理工艺的关系进行了研究。Fenton氧化促进了污泥的过滤性能，导致毛细抽吸时间值约为原始污泥的50%，而高输入能量的超声处理会恶化污泥的过滤性能。预处理工艺还提高了污泥的生物降解性，在总固体浓度为25g/L时，生污泥、超声波污泥和芬顿氧化污泥的可生化性达到最大值(分别为%、77%和73%)。因此，废水污泥的预处理改变了流变性，从而：(1)改善了污泥的流动性，便于通过处理系统(通过管道和水泵)输送；(2)废水污泥的脱水性能得到提高，以便最终处置；(3)微生物对养分的吸收为进一步的增值服务。(C)2009爱思唯尔B.V.保留所有权利。
The effect of ultrasonication and Fenton oxidation as physico-chemical pre-treatment processes on the change of theology of wastewater sludge was investigated in this study. Pre-treated and raw sludges displayed non-Newtonian rheological behaviour with shear thinning as well as thixotropic properties for total solids ranging from 10 g/L to 40 g/L. The theological models, namely, Bingham plastic, Casson law, NCA/CMA Casson, IPC Paste, and power law were also studied to characterize flow of raw and pre-treated Sludges. Among all theological models, the power law was more prominent in describing the theology of the sludges. Pre-treatment processes resulted in a decrease in pseudoplasticity of sludge due to the decrease in consistency index K varying from 42.4 to 1188, 25.6 to 620.4 and 52.5 to 317.9; and increase in flow behaviour index n changing from 0.5 to 0.35, 0.62 to 0.55 and 0.63 to 0.58, for RS, UIS and FS, respectively at solids concentration 10-40 g/L. The correlation between improvement of biodegradability and dewaterability, decrease in viscosity, and change in particle size as a function of sludge pre-treatment process was also investigated. Fenton oxidation facilitated sludge filterability resulting in capillary suction time values which were approximately 50% of the raw sludges, whereas ultrasonication with high input energy deteriorated the filterability. Biodegradability was also enhanced by the pretreatment processes and the maximum value was obtained (64%, 77% and 73% for raw, ultrasonicated and Fenton oxidized sludges, respectively) at total solids concentration of 25 g/L Hence, pre-treatment of wastewater sludge modified the theological properties so that: (1) the flowability Of Sludge was improved for transport through the treatment train (via pipes and pumps); (2) the dewaterability of wastewater sludge was enhanced for eventual disposal and; (3) the assimilation of nutrients by microorganisms for further value-addition was increased. (C) 2009 Elsevier B.V. All rights reserved.