摘要
为了研究铁元素对A^2O工艺污泥絮凝性的影响,考察Fe^(3+)在污泥上清液、胞外聚合物(extracellular polymeric substances,EPS)与底泥(Pellet)中的分布和迁移转化规律,结合三维荧光光谱(3D-EEM)、原子吸收和X射线衍射仪(XRD)分析Fe的存在形态和结构特征,揭示Fe^(3+)与微生物代谢产物的作用机制,探索Fe^(3+)对脱氮除磷效率的影响。结果表明:低浓度Fe^(3+)(<10 mg·L^(-1))能够提高COD和TN去除率,促进微生物活性,增强污泥生物絮凝性;高浓度Fe^(3+)(10～40 mg·L^(-1))则抑制微生物活性,使EPS总量升高,污泥絮体脱稳,LB、TB层PN/PS是影响污泥絮凝性的关键因素;Fe^(3+)的投加强化生物除磷效率,当Fe^(3+)浓度为40 mg·L^(-1)时,TP去除率为93%。Fe^(3+)在污泥混合液中的分布规律为TB>上清液>LB>SMP,Fe^(3+)在生物体内富集累积,能够改变EPS各层的组分。
To study the effect of iron on the flocculation of A^2O process sludge, the distribution and migration and tranformation of Fe^3+ in sludge supernatant, extracellular polymeric substances (EPS) and sediment (Pellet) were investigated. A large amount of wastewater containing Fe^3+ was generated in the rapidly developed industries such as metallurgy, electroplate and mineral separation. Fe^3+ entered the sewage biological treatment system and could affect the sludge biological flocculation and the removal of COD, TN and TP. Information on the morphology, structure change, migration and conversion of iron ions in the anaerobic, anoxic and oxic sludge was scrace. The occurrence form and structural characteristics of iron ions were analyzed and the interaction mechanism between Fe^3+ and microbial metabolites was revealed based on the analyses of three-dimensional excitation (3D-EEM), atom absorption and X-ray diffraction (XRD). The effect of Fe^3+ on the denitrification and phosphorus removal was explored. The results showed that low concentration of Fe^3+(<10 mg · L^-1 ) could improve COD and TN removal, promote microbial activity and enhance the biological flocculation of sludge. When Fe^3+ increased from 0 to 10 mg· L^-1 , the removal efficiency of COD and TN increased from 42% and 37% to 60% and 45%, respectively, while the dehydrogenase activity increased from 20.09 mg ·(L · h)^-1 to 31.91 mg ·(L · h)^-1. The flocculation ability (FA) increased from 30% to 53% and the maximum sludge particle size was 43.3 ?m. High concentration of Fe^3+ could inhibit microbial activity, increase EPS content and induce sludge deflocculation. When Fe^3+ concentration increased from 10 mg · L^-1 to 40 mg · L^-1 , the removal efficiency of COD and TN decreased by 28% and 34%, respectively. Protein (PN)/polysaccharide (PS) in loosely bound EPS(LB) and tightly bound EPS(TB) was the key factor affecting the flocculation of sludge. Fe^3+ addition could enhance TP removal efficiency and it was 93% when Fe^3+ was 40 mg · L^-1. Fe
作者
张兰河
张明爽
郭静波
贾艳萍
李正
陈子成
ZHANG Lanhe;ZHANG Mingshuang;GUO Jingbo;JIA Yanping;LI Zheng;CHEN Zicheng(School of Chemical Engineering, Northeast Electric Power University, Jilin 132012, Jilin, China;Key Laboratory of Songliao Aquatic Environment, Ministry of Education, Jilin Jianzhu University, Changchun 130118, Jilin, China;School of Civil and Architecture Engineering, Northeast Electric Power University, Jilin 132012, Jilin, China)
出处
《化工学报》
EI
CAS
CSCD
北大核心
2019年第3期1089-1098,共10页
CIESC Journal
基金
国家自然科学基金项目(51678119
51508073)
吉林省科技发展计划项目(20180201016SF
20180101309JC
20170519013JH)
关键词
FE
废水
生物反应器
缺氧污泥
迁移转化
形态学
生物絮凝性
iron
wastewater
bioreactors
anoxic sludge
migration and transformation
morphology
biological flocculation
