原位CaCO_(3)结晶调理给水厂含藻污泥  

Conditioning algae-laden sludge in drinking water plant by in-situ CaCO_(3) crystallization

作　　者：何晓龙 易晋 毛颖 HE Xiaolong;YI Jin;MAO Ying(Department of Water Conservancy and Construction Engineering,Beijing Vocational College of Agriculture,Beijing 102442,China;Shenzhen Longhua Drainage Co.,Ltd.,Shenzhen 518000,China;Shenzhen Polytechnic School of Architectural Engineering,Shenzhen 518055,China)

机构地区：[1]北京农业职业学院水利与建筑系,北京102442 [2]深圳市龙华排水有限公司,深圳518000 [3]深圳职业技术学院建筑工程学院,深圳518055

出　　处：《给水排水》2023年第8期18-23,36,共7页Water & Wastewater Engineering

基　　金：湖南省自然科学基金项目(2020JJ4609);湖南省水利科技项目(湘水科技[2020]194-32)。

摘　　要：给水厂含藻污泥结构松散、浓缩脱水性能差,导致浓缩脱水时间长,加剧藻细胞的自溶,产生藻毒素、致嗅物质和消毒副产物等排泥水回用风险。为改善含藻污泥的浓缩脱水性能,采用原位CaCO_(3)结晶对含藻污泥进行调理,分析了原位CaCO_(3)结晶的藻水分离效果和对含藻污泥浓缩脱水性能的改善效果,结合Zeta电位、粒径分析和污泥表征结果,研究了原位CaCO_(3)结晶机理。结果表明,原位CaCO_(3)结晶具有良好的藻水分离效果,明显改善含藻污泥的浓缩脱水性能。经调理后,上清液残留藻细胞不足0.6%,毛细吸水时间(CST)降低80%以上,调理过程同步实现污泥浓缩,体积减小14.3倍以上。原位CaCO_(3)结晶调理主要是通过结晶颗粒的吸附电中和和颗粒架桥实现,生成的结晶污泥具有粒径大和致密性高的特点。The algae-laden sludge in drinking water plant is characterized by loose structure and poor performance of thickening and dewatering,leading to long time for sludge thickening and dewatering,which results in the lysis of algae cells and eventually increase the risk of microcystins,odor compounds and disinfect by-products.In order to improve the thickening and dewatering properties of algae-laden sludge,conditioning test was conducted using in-situ CaCO_(3) crystallization.During in-situ CaCO_(3) crystallization,the cells-liquid separation performance and improvement effect of thickening and dewatering properties were investigated.Moreover,the conditioning mechanism was illuminated by evaluating the Zeta potential change,particle size and characteristics of crystal-laden sludge.The results show that in-situ CaCO_(3) crystallization exhibited good cells-liquid separation performance,and significantly improved thickening and dewatering properties of algae-laden sludge.After conditioning,the residual cell concentration in supernatant was lower than 0.6% of that of initial,and 80% reduction of CST could be achieved.Also the simultaneous thickening effect was obtained during conditioning process,with volume reduction of 14.3 times.The underlying conditioning mechanism of in-situ CaCO_(3) crystallization conditioning was proposed to be charge neutralization and particle bridging of CaCO_(3) crystal to cells.The crystal-laden sludge is characterized by large particle size and compact structure.

关 键 词：原位CaCO_(3)结晶 含藻污泥 调理 浓缩脱水 吸附电中和 

分 类 号：TU991[建筑科学—市政工程]