酸及磁化处理对污泥沉降与脱水性能影响研究

研究酸处理及磁化对污水处理厂活性污泥沉降性能的影响。通过对不同pH值下污泥沉降性能曲线的分析、微观照片的观察、离心脱水性能的考察,得出pH值为4时污泥沉降性能最佳、2000r/min下10min的离心效果最好;比较两组不同MLSS污泥在不同磁感应强度、不同磁场位型下污泥沉降曲线和磁化前后的颗粒微观照片,得出磁场的确能够改善污泥的沉降性能。     

溶菌酶辅助壳聚糖调理对活性污泥脱水性能的影响及其机理

通过测定真空抽滤泥饼含水率、污泥比阻、污泥ζ电位,研究溶菌酶辅助壳聚糖调理对活性污泥脱水性能的影响,并通过提取污泥絮体形态学特征进行二维分形维数(D₂)分析,深入剖析污泥脱水机理。结果表明,溶菌酶辅助壳聚糖调理后泥饼含水率下降了约21.3%,污泥比阻下降了约94.5%,活性污泥脱水性能得到显著提高。分析调理前后的污泥ζ电位和絮体形态,发现污泥双电层被压缩,污泥|ζ|电位降至0.28 mV,同时污泥絮体密实程度增加,D₂值提高到1.748,说明溶菌酶辅助壳聚糖调理活性污泥可以促进污泥胶体的脱稳、絮凝,压缩絮体颗粒间孔隙并释放部分间隙水。     

磁化活性污泥强化SBR工艺性能的实验研究

通过向传统 SBR反应器中投加适当的强磁性粉末（Fe₃O₄）以强化活性污泥沉淀性能、降低污泥负荷,实现了反应器内污水处理效果的增强。实验结果表明：投加的磁粉粒度为 30 nm,磁粉浓度为 2 000 mg/L时,整体优于传统SBR 法,期间 COD、NH₄⁺-N、TP 的平均去除率分别为 98.51%、95.27%、83.90%;磁粉加入后,提高了污泥浓度,即使SV₃₀达到 70% 以上,MLSS 达到 9 500 mg/L 左右时,在处理高浓度的食堂淘米污水条件下,反应器也可以正常运行;实验期间3种工况均对COD、NH₄⁺-N 去除效果较好,对 TP、TN 去除率也能达到 70% 左右。     

絮凝活性污泥的离心的脱水研究

用ＷＬ－２００Ｎ卧式螺旋御料沉降离心机进行了絮凝活性污泥离心脱水研究。由于合适絮凝剂的作用，使固相回收率和沉渣含湿量都有很大的改进。为工业用离心机的模拟放大设计和使用提供了理论依据。     

超声与阳离子型聚丙烯酰胺联合作用对剩余活性污泥脱水的影响

对石化污水处理厂的剩余活性污泥采用超声与阳离子型聚丙烯酰胺(CPAM)联合作用促进脱水的情况进行了研究。实验结果表明,单独添加CPAM虽然改善了污泥的脱水性质,加快了过滤速率,但要达到较好的脱水效果,CPAM添加量比较大。用超声对污泥进行预处理后,污泥脱水能力得到了强化,不但可以减少CPAM用量,还可以使污泥滤饼含水率降低约2个百分点(质量分数)。采用28.7 kHz超声处理时,最佳处理时间为2 min左右,声强约为470 W/m2,CPAM添加量约为0.5%(污泥干基质量分数)。     

冻融处理对预脱水净水污泥脱水性能的影响

针对净水污泥含水率高、脱水性能差的问题,采用具有良好脱水效果的冻融法调理,并进一步调理经过预脱水的低含水率污泥,以期提高脱水效能。考察冷冻温度、时间和初始含水率对冻融调理的影响,并分析污泥各方面的变化,探究冻融作用机理。结果表明,净水污泥经冻融调理后脱水性能有明显提升,在-12 ℃下冷冻 12 h 后,其污泥比阻（SRF）、泥饼含水率和污泥沉降比(SV₃₀)分别可降至 1.57×10¹²m/kg、59.9% 和 20.2%。而预脱水污泥的冻融调理效果相较于原泥直接冻融有进一步提升,且初始含水率越低（80% 以上）,脱水效果越好,最佳冻融条件下（含水率82%,-12 ℃,6 h）,其泥饼含水率、SRF 分别为 46.5% 和 1.51×10¹¹m/kg,相较于原泥降低了 50.8% 和 99.5%。而冻融改善污泥脱水性能的可能机理为在生长冰晶的不断作用下破坏了污泥原有的絮体结构,并相互团聚成大颗粒污泥,同时增强了污泥增溶性和疏水性,使自由水以不可逆的方式显著增加。     

炼油厂剩余活性污泥脱水处理研究

对炼油厂剩余活性污泥进行脱水处理,确定了絮凝剂及其投加量,并考察了相关运行参数对污泥脱水效果的影响。结果表明,在PAC投加量为200mg·mL^-1、CPAM投加量为25mg·mL^-1、操作温度为40℃、污泥初始pH值为8.0、快搅强度为170r.min^-1、快搅时间为60s、慢搅强度为50r.min^-1、慢搅时间为8min的最佳条件下,污泥的脱水效果明显得到改善。在此条件下进行了多次实验,泥饼的含水率均低于81.63%。     

重金属离子对活性污泥系统处理性能的影响

采用简单活性污泥法研究了Cu^ 、Cd^ 、Cr^ 等重金属离子对活性污泥指数和系统处理废水能力影响,解释了在重金属离子存在条件下,活性污泥系统对生活废水的处理能力下降的原因。由于重金属离子对活性污泥中原生动物和细菌的毒性,导致污泥沉降指数SV和污泥容积指数SVI不同程度改变,出水的BOD5／COD大幅度减小。实验发现,Fe^3 、Zn^2 浓度小于40mg／L时对COD的去除能力影响非常小;而当Cu^2 浓度大于40mg／L时．污泥系统COD去除率小于10％,系统失去意义。Pb^2 、Cd^2 、Cr^3 在浓度大于40mg／L时,出水的COD去除率下降50％左右。通过建立简单有效的入水监控手段,可避免未处理污水排出。     

改性膨润土对污泥脱水性能的影响

以改性膨润土为絮凝剂对城市生活污水处理厂二沉池剩余活性污泥进行预处理。研究了改性膨润土用量、粒径、不同改造剂投加量等因素对污泥脱水性能的影响。结果表明,改性膨润土投加量增加到一定程度时,污泥脱水性能好;改性膨润土粒径越小,污泥脱水性能越好;改造剂投加量为4 mL/100 mL污泥(即0.22 g/100 mL污泥)时,改性膨润土对污泥脱水性能较佳,最佳处理效果为66.43%(污泥含水率)。     

Effects of current density and electrode material on the dewaterability of the thickened activated sludge by electro‐flotation

BACKGROUND: Electro‐flotation (EF) could improve thickening and subsequent dewatering characteristics of activated sludge although the settling characteristics of the sludge were very poor. The objectives of this study were to evaluate the performance of EF in the thickening and dewatering of activated sludge and the effects of current density and electrode material on the dewaterability of the sludge. RESULTS: The specific resistance to filtration (SRF) of the sludges thickened by EF was much lower than that by gravity sedimentation. The SRF of the thickened sludge decreased exponentially with increase of gas generation rate of the EF system. Gas generation rate could be controlled by varying the current density of the electrode. Degassing of the microbubbles by moderate mixing of the thickened sludge layer deteriorated the dewaterability of the sludge. Therefore, it is obvious that the gas bubbles entrapped in the thickened sludge play a key role in the observed dewaterability improvement. The effect of electrode material on the thickening and dewatering efficiency was trivial compared with the effect of current density of the electrode. CONCLUSION: The EF system was quite promising as an alternative to gravity sedimentation for thickening of activated sludge and the dewaterability was also improved by microbubbles generated in the system. Copyright © 2009 Society of Chemical Industry     

洗毛废水蒸馏处理塔中污泥的改性及其对污泥脱水效果的影响

洗毛废水蒸馏后形成的污泥虽含较多的有机质和植物养料,也具有很高的热值,但由于富含羊毛脂,黏度高、碱性强、极难脱水,极大地限制了它的资源化利用。根据污泥体系中表面活性剂的乳化作用与破乳的基本原理,通过采用酸化、投加凝聚剂、破乳剂和调节适当反应温度等联合方法,有效地破坏了供试污泥分散体系固有的稳定性,改性后污泥的比阻值R从改性前的大于9.81×1013m/kg下降为2.48×1011m/kg,从而使污泥极易机械脱水。为洗羊毛污泥的资源化利用提供了一个全新的预处理工艺。     

Fenton处理对污泥脱水性、重金属形态及生物淋滤效率影响

为考察污泥预处理过程中重金属迁移转化规律,通过投加不同量的Fenton试剂对污泥进行处理,分析了Zn、Cd、Mn、Ni四种重金属的化学形态变化与后继生物淋滤过程的溶出行为。研究结果表明,污泥经Fenton处理后,毛细吸水时间在短时间内降低,但对生物淋滤后最终的污泥脱水性没有显著提升作用;重金属Zn、Cd、Mn的不稳定态（弱酸提取态、可还原态）比例不同程度提高,当投加Fe²⁺=1.00g/L、H₂O₂=9.00g/L时,其比例分别由37%、84%、79%上升至90%、93%、84%,但Ni无明显变化。此外,Fenton处理污泥中Zn、Cd、Mn、Ni四种重金属生物淋滤后含量分别由3451.52mg/kg、6.45mg/kg、443.40mg/kg、94.96mg/kg降至376.74mg/kg、1.10mg/kg、141.66mg/kg、21.77mg/kg,比单独生物淋滤处理污泥重金属残余量分别降低了36.20%、26.17%、30.92%和27.89%。利用动力学方程较好地描述了生物淋滤过程中Zn、Cd、Mn、Ni四种重金属的溶出速率的相对大小,排序为Mn＜Cd＜Zn＜Ni。     

Influence of microwave irradiation on sludge dewaterability

The study focuses on the effect of microwave irradiation on sludge dewaterability. Capillary suction time and specific resistance of filtration were used to evaluate sludge dewaterability. Soluble chemical oxygen demand, extracellular polymeric substance (EPS) content and sludge particle size were determined in an attempt to explain the observed changes in sludge dewaterability. The results indicated that microwave application slightly enhanced sludge dewaterability with short contact time, while it significantly deteriorated sludge dewaterability with long contact time. The results show that 900 W and 60 s is an ideal microwave condition, yielding maximum sludge dewaterability characteristics by generating sludge with optimal disintegration (1.5–2%), EPS concentration (1500–2000 mg/l), and particle size distribution (120–140 μm).     

Enhancing dewaterability of sewage sludge by the application of tween-20 during bioleaching: Performance evaluation and mechanistic study

Dewatering is recognized as an important method for treating sewage sludge before its disposal. In this paper, the nonionic surfactant Tween-20 was used for the first time to improve the dewaterability of sewage sludge during bioleaching. The specific resistance to filtration (SRF), water content (WC) and bound water content (BW) of the sludge cake were used to evaluate sludge dewaterability. The results indicated that a 1?g/L Tween-20 dosage with an inoculum ratio of 20%, a S⁰ dosage of 2?g/L and a FeSO₄?·?7H₂O dosage of 10?g/L provided oxidation efficiencies up to 100% for Fe²⁺ and 65.8% for S⁰. The SRF of the bioleached sludge decreased to as low as 0.81?×?10¹²?m/kg from the initial 12.6?×?10¹²?m/kg for raw sludge. A WC of 47.16% was achieved while 48.1% of BW was released during bioleaching. The results from this study indicate that adding of an appropriate amount of Tween-20 to sewage sludge is a promising method to enhance dewaterability by bioleaching.     

活性污泥与灭活污泥的吸附性能比较

用活性污泥制备灭活干污泥来与原活性污泥进行针对生活污水的吸附试验,比较两种污泥吸附能力的差别,分析生物作用对吸附的影响。发现温度对活性污泥的影响比对灭活污泥的影响大;两种污泥的吸附结果都能用伪一级和伪二级方程进行拟合;活性污泥比灭活污泥的吸附容量大,活性污泥和灭活污泥的最大吸附容量分别为101.01和35.46 mg/g。     

Ozonation of activated sludge in the recycle stream

Intermittent ozonation of a part of the recycle sludge was performed two times a week for a laboratory‐scale reactor at an average ozone dose of 0.019 g O₃(gSS_ozonated)^?1. Under these conditions a decrease of about 50% in sludge growth was obtained for the ozone‐treated system, in comparison with the control. As a consequence less sludge had to be removed from the test reactor. Only a slight decrease in quality of effluent was noticed. A comparative cost calculation was made, based on these results, between an ozone‐treated activated sludge system and a traditional activated sludge system. © 2001 Society of Chemical Industry     

臭氧氧化对活性污泥特性的影响

研究了对活性污泥采用臭氧处理,以考察污泥的减量效果及其对污泥特性的影响。结果表明:在臭氧投加量0.01～0.15gO3/gVSS范围内,污泥浓度显著下降、SCOD浓度迅速升高,活性污泥总悬浮固体(TSS)最大可以减少39.6%,SCOD浓度可提高60.6倍,污泥的SCOD产率为0.6739gSCOD/gVSS,同时发现,破解后的污泥活性和体积指数SVI下降;试验确定最佳臭氧投加量在0.03gO3/gVSS左右。试验结果对今后污泥减量技术的推广应用提供了理论基础。     

活性污泥工艺传统设计方法中存在问题的探讨

污泥负荷法和泥龄法是活性污泥工艺设计的主要计算方法,这2种设计方法偏于安全、保守,以经验为主,没有反映出活性污泥工艺中生物反应机理,缺少理论支持,适用范围窄,而数学模型法才是活性污泥法设计的发展趋势,利用数学模型进行活性污泥工艺设计可以有2种方法选用:试算法和优化法。