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561.
3×2500m3高炉因煤气洗涤水质达不到要求,造成戴维塔喷嘴堵塞、冷却塔结垢和塌陷.选用聚铝、复合碱性氯化铝(PAC)、ZMT-642高分子絮凝剂和ZMD-400缓蚀阻垢剂进行药剂处理效果优化试验,最终确定较佳的处理方案为:ZMT-642 1.0-1.5ppm,ZMD-400 1.0ppm.  相似文献   
562.
3×2500m^3高炉因煤气洗涤水质达不到要求,造成戴维塔喷嘴堵塞、冷却塔结垢和塌陷。选用聚铝、复合碱性氯化铝(VAC)、ZMT-642高分子絮凝剂和ZMD-400缓蚀阻垢剂进行药剂处理效果优化试验,最终确定较佳的处理方案为:ZMT-6421.0—1.5ppm,ZMD-4001.0ppm。  相似文献   
563.
酵母菌降解胞外聚合物提升剩余活性污泥的脱水性能   总被引:1,自引:1,他引:0  
剩余污泥的脱水性能直接影响到污泥处置的效果和成本,提升污泥脱水性是污泥减量化的重要途径.本研究提出利用复合酵母菌群降解剩余污泥胞外聚合物(EPS)来提升污泥脱水性能的方法.首先评价了复合酵母菌群对灭菌后EPS中各组分的降解效果;继而将混合酵母细胞接入剩余污泥中进行曝气,考察了酵母菌对污泥脱水性的提升效能.研究结果表明,酵母菌对提取的EPS中蛋白质、多糖和核酸的降解效果明显,振荡培养72 h内最多分别降低了(60. 43±2. 73)%、(18. 94±2. 39)%和(48. 30±3. 37)%.向2 L剩余污泥中接入1. 5 g混合酵母菌湿菌体进行曝气,24 h后污泥的毛细吸水时间(CST)下降了(17. 19±1. 16)%,比对照组多下降了(7. 03±1. 35)%;与此同时污泥中EPS总量比对照污泥多下降了(17. 46±3. 91)%,表明酵母菌可以通过原位降解污泥中EPS来提高污泥的脱水性能.  相似文献   
564.
The present study investigated the relationship between N-acyl-homoserine lactone(AHL)-based quorum sensing(QS) and the physico-chemical properties of aerobic granules.Stable mature granules were observed in SBR2 and SBR3 with average diameters of 0.96,and1.49 mm,respectively. The sludge densities of aerobic granules in SBR2 and SBR3 were1.0246,and 1.0201 g/mL,respectively,which were higher than that of flocculent sludge in SBR1(1.0065 g/mL). The results showed that the activity of AHL-based QS in SBR2 and SBR3 amounted to 2.4- and 2.1-fold induction,however,that in SBR1 with flocculent sludge was1.6-fold induction. In addition,the results also showed that the activity of AHL-based QS in the three reactors rose in the feast condition,and then dropped with the consumption of substrate. However,the activity of AHL-based QS in these three reactors recovered again in prolonged starvation. Furthermore,the results showed that the enhancement of AHL-based QS favored the extracellular polymeric substance production of microorganisms in activated sludge. Thus,it could be concluded that aerobic granules showed higher AHL-based QS than flocculent sludge,which resulted from the higher sludge density of aerobic granules than flocculent sludge. AHL-based QS was related to the metabolism energy in the feast condition; however,in prolonged starvation,microorganisms would emit more AHL-like molecules to protect themselves to resist starvation. Moreover,the enhancement of AHL-based QS favored the EPS component productivity of the microorganisms in activated sludge,which contributed to maintain the aerobic granular structure.  相似文献   
565.
为探索低浓度生化尾水生物深度处理的快速挂膜方法,采用4种方法(投加壳聚糖法、投加铁离子法、接种排泥法和自然挂膜法)进行挂膜,考察其对生物膜主要特性(生物膜量MLSS、胞外聚合物(EPS))和废水处理效果的影响.结果表明:在挂膜期间,投加壳聚糖法有利于生物膜量、EPS迅速增加,两者平均含量达到4种方法中的最大值,分别为(9.26 ±3.30) mg/cm3和(42.51 ±33.49) mg/(gSS),但其生物膜活性f值最低,污染物的去除效果不是最佳;投加铁离子成膜时,生物膜特性稳定,活性高,污染物去除效果最佳,CODCr、NH4+-N、TP去除率分别较快稳定在(66.13 ±2.30)%、(92.03 ±7.72)%和(62.75 ±4.41)%;接种排泥法的生物膜量、EPS均含量、污染物去除效果比投加壳聚糖、铁离子法稍低;自然挂膜法前期对污染物去除率低,稳定时间较长,除TP外,CODCr、NH4+-N去除率在挂膜后期与投加壳聚糖法、接种排泥法相差不大.综合地看,投加铁离子法,虽然生物膜量、EPS含量略低于投加壳聚糖法,但生物膜活性高、污染去除效果好,是低浓度尾水挂膜的最佳方法.  相似文献   
566.
Extracellular polymeric substances (EPS) form a stable gel-like structure to combine with water molecules through steric hindrance, making the mechanical dewatering of wastewater sludge considerably difficult. Coagulation/flocculation has been widely applied in improving the sludge dewatering performance, while sludge properties (organic fraction and solution chemistry conditions) are highly changeable and have important effects on sludge flocculation process. In this work, the alkalinity effects on sludge conditioning with hydroxy-aluminum were comprehensively investigated, and the interaction mechanisms between EPS and hydroxy-aluminum with different speciation were unraveled. The results showed that the effectiveness of hydroxy-aluminum conditioning gradually deteriorated with increase in alkalinity. Meanwhile, the polymeric hydroxy-aluminum (Al13) and highly polymerized hydroxy-aluminum (Al30) were hydrolysed and converted into amorphous aluminum hydroxide (Al(OH)3), which changed the flocculation mechanism from charge neutralization and complexing adsorption to hydrogen bond interaction. Additionally, both Al13 and Al30 showed higher binding capacity for proteins and polysaccharides in EPS than monomeric aluminum and Al(OH)3. Al13 and Al30 coagulation changed the secondary structure of proteins in EPS, which caused a gelation reaction to increase molecular hydrophobicity of proteins and consequently sludge dewaterability. This study provided a guidance for optimizing the hydroxy-aluminum flocculation conditioning of sludge with high solution alkalinity.  相似文献   
567.
无机复合高分子混凝剂具有效果好,稳定性高,原料来源广,价格低廉等特点,因而其研制和应用已成为热点和发展趋势。综述了近年来国内外发展现状,着重介绍了其主要性能及在水处理中的应用。  相似文献   
568.
聚合硫酸铁处理终端焦化废水的研究   总被引:2,自引:0,他引:2  
确定了聚合硫酸铁处理终端焦化废水的最佳投药量和 p H值 ,讨论了影响其混凝效果的主要因素。实验结果表明 ,处理后出水 COD、浊度的去除率达 80 %以上 ,对酚、氰的去除率可达到 40 %、5 0 %。  相似文献   
569.
Manganese ion (Mn2+) generated from metallurgical, steel making and chemical industries enters sewage treatment plants and affects the sludge activity and flocculation. The effect of Mn2+ on the removal of chemical oxygen demand (COD) and total phosphorus (TP) and sludge activity were investigated in anoxic zone of an anaerobic/anoxic/oxic (A2O) process. The compositions and structures of extracellular polymeric substances (EPS) were characterized using three-dimensional excitation emission matrix fluorescence spectroscopy (3D-EEM), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) to reveal the relationship among Mn2+, EPS and sludge flocculation.The results showed that low concentration of Mn2+ (<5 mg/L) improved removal efficiencies of COD and TP and increased the activity of alkaline phosphatase, acid phosphatase and dehydrogenase. Meanwhile, the addition of Mn2+ increased total EPS, sludge contact angle, Zeta potential and sludge particle size, and thus enhanced sludge flocculation. However, high concentration of Mn2+ (>10 mg/L) hindered microbial flocculation and reduced removal efficiencies of the pollutants. When Mn2+was 5 mg/L, removal efficiencies of COD and TP reached 65% and 90%, respectively. Sludge flocculation was the best and SVI was 70.56 mL/g. The changes of Mn2+ concentration caused deviation of groups’ compositions in LB-EPS and TB-EPS, where the main components were always protein (PN) and polysaccharide (PS). The addition of Mn2+ resulted in the degradation of humic acids. However, it did not give rise to significant morphology changes of EPS.  相似文献   
570.
采用白腐菌和纳米零价铁(nZVI)联合体系强化去除水中Cd (II),并考察pH值、Cd (II)初始浓度、温度、nZVI投加量对Cd (II)去除的影响,分析nZVI对白腐菌胞内外富集镉的影响特性,同时结合扫描电镜、红外光谱、X射线光电子能谱、三维荧光光谱等手段分析联合体系对Cd (II)的强化去除机制.结果表明,在pH=6,Cd (II)初始浓度为50mg/L,温度为30℃,nZVI投加量为0.1g/L的条件下反应180min后,Cd (II)的去除率可达到99.5%以上.联合体系对Cd (II)的去除过程符合准二级动力学,主要去除机制为白腐菌对Cd (II)的胞外络合吸附,添加nZVI能促进白腐菌对Cd (II)的胞外吸附,FTIR和XPS分析表明,羟基、羧基和氨基参与了Cd (II)的吸附,白腐菌胞外聚合物(EPS)能与铁发生内层配位形成P-O-Fe键,加速富含羟基官能团的纤铁矿、磁铁矿等铁矿物形成,从而促进对溶液中Cd (II)的吸附去除.  相似文献   
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