热改性给水污泥联合酸提液调理促进剩余污泥脱水  

Heat Modified Sludge from Waterworks Combined with Its Acid Extract Conditioning to Promote Excess Sludge Dewatering

作　　者：张彦平 郑松超 孙雪萌 李芬[3] 李一兵 ZHANG Yan‑ping;ZHENG Song‑chao;SUN Xue‑meng;LI Fen;LI Yi‑bing(School of Civil and Transportation,Hebei University of Technology,Tianjin 300401,China;China Construction Sixth Engineering BureauGreen Building Technology Co.Ltd.,Tianjin 300451,China;School of Materials Science and Chemical Engineering,Harbin University of Science and Technology,Harbin 150040,China)

机构地区：[1]河北工业大学土木与交通学院,天津300401 [2]中建六局<天津>绿色建筑科技有限公司,天津300451 [3]哈尔滨理工大学材料科学与化学工程学院,黑龙江哈尔滨150040

出　　处：《中国给水排水》2023年第13期39-46,共8页China Water & Wastewater

基　　金：国家自然科学基金资助项目(51608166)。

摘　　要：为了改善剩余污泥的脱水性能,采用热改性给水污泥(HMS)联合其酸提液调理剩余污泥,研究了联合调理对污泥脱水性能的影响和机理。结果表明,当HMS投加量为30%(以干污泥DS计)、酸提液投加量为8 mg/g(以Fe/DS计)时,污泥毛细吸水时间(CST)和污泥比阻(SRF)分别降至10.3 s和0.83×10^(9)s^(2)/kg,较HMS联合FeCl_(3)的调理效果进一步降低了48.8%和37.3%,药剂使用量降低了约60%。调理过程中,HMS可作为骨架颗粒,使污泥压缩系数由1.39降至0.82,提高污泥的透水性;酸提液中的Fe、Al、Ca等金属阳离子有助于增大污泥絮体体积、使结构更密实,使得分形维数从1.29增至1.65;酸提液及HMS溶解出的阳离子可中和污泥表面的负电荷,使Zeta电位升至0.15mV,有利于污泥絮体团聚与脱水;在HMS和酸提液的共同作用下,胞外聚合物(EPS)总量降低(多糖降低了30.9%、蛋白质降低了36%),且伴随着紧密结合型EPS(TB-EPS)向疏松结合型EPS(LBEPS)和可溶性EPS(S-EPS)的转化,从而使得污泥的脱水性能得到较大提高。经HMS联合酸提液调理后,污泥上清液浊度及SCOD较原污泥分别降低了86.9%和73.2%,有利于后续处理。This paper used heat modified sludge(HMS)from waterworks combined with its acid extract to condition excess sludge,and investigated the effect of the combined conditioning on sludge dewatering performance and its mechanism,so as to improve the dewatering performance of excess sludge.When the dosages of HMS and acid extract were 30%and 8 mg/g,the capillary suction time(CST)and specific resistance to filtration(SRF)of sludge were reduced to 10.3 s and 0.83×10^(9)s^(2)/kg,respectively.Compared with conditioning by FeCl_(3)combined with HMS,the CST and SRF were further reduced by 48.8%and 37.3%,and the dosage of agent was reduced by 60%.In the conditioning process,HMS served as the skeleton particle,which reduced the sludge compression coefficient from 1.39 to 0.82,and improved the water permeability of the sludge.The cations such as Fe,Al and Ca in the acid extract were conducive to increase the volume and compact the structure of the sludge flocs,and increased the fractal dimension from 1.29 to 1.65.The cations dissolved by the acid extract and HMS neutralized the negative charge on the surface of the sludge,and increased the Zeta potential to 0.15 mV,which was conducive to the agglomeration and dewatering of the sludge flocs.Under the combined action of HMS and acid extract,the total content of extracellular polymer(EPS)decreased(30.9%for polysaccharide and 36%for protein),which was accompanied by the conversion of tightly bounded EPS(TB‑EPS)to loosely bounded EPS(LB‑EPS)and soluble EPS(S‑EPS),indicating that the dewatering property of sludge was greatly improved.After the sludge was conditioned by HMS combined with acid extract,the turbidity and SCOD in supernatant were reduced by 86.9%and 73.2%respectively compared with the raw sludge,which was conducive to subsequent treatment.

关 键 词：污泥脱水 给水污泥 酸提液 骨架构建 分形维数 

分 类 号：TU992[建筑科学—市政工程]