超声耦合类Fenton对制革污泥脱水性能的影响研究

制革污泥中含有大量的有毒物质,较差的脱水性能制约制革污泥的处理与处置。目前促进污泥脱水性能的方法,在一定程度上能改进制革污泥的脱水性能,副作用阻碍在实际中的运用。文章通过分析对超声和类Fenton进行分析,探究超声耦合类Fenton对制革污泥脱水性能的影响的可行性。     

Fenton联合氧化钙调理强化船舶含油生化污泥的脱水性能

油船洗舱和压载含油废水生化处理污泥采用Fenton氧化联合氧化钙的工艺处理,以提高脱水性能,实现深度减量。实验考察了初始pH值、Fe²⁺和H₂O₂投加量对污泥脱水性能的影响,并探讨污泥深度脱水的作用机制。结果表明,初始pH为4.0,Fe²⁺、H₂O₂、CaO投加量分别为20,30,60 mg/g干基(DS)时,污泥脱水性能提升最大,处理后污泥的比阻(SRF)降低了95%。高压压滤结果表明,Fenton氧化联合氧化钙工艺处理后泥饼的含水率降低至(42.65±0.25)%,实现船舶含油生化污泥深度脱水,处理成本为391.05元/t DS。机理研究结果表明,酸处理和Fenton反应都有助于中和污泥颗粒表面电荷,提高污泥颗粒的絮凝能力,进而降低结合水含量。酸处理能有效去除溶解型胞外聚合物(S-EPS),然而Fenton反应可有效氧化S-EPS和松散结合型胞外聚合物(LB-EPS),并实现紧密结合型胞外聚合物(TB-EPS)的部分去除。     

基于Fenton高级氧化-骨架构建体的污泥深度脱水研究

以城市污水处理厂的浓缩池污泥作为研究对象,研究了基于Fenton高级氧化技术-骨架构建体组合对污泥脱水性能的影响。结果表明,Fenton高级氧化和骨架构建体组合能够显著改善污泥的脱水性能,当pH约为5,Fe~(2+)投加量为45 mg/g,H_2O_2投加量为315 mg/g,生石灰和粉煤灰投加量均为500 mg/g时,复合调理污泥的脱水性能最佳,脱水污泥含水率为51.52%。     

Fenton氧化技术的应用研究进展

Fenton氧化法是一种高级氧化技术。本文主要阐述了Fenton氧化法的反应原理,并讨论pH、反应温度等因素对处理效果的影响。在Fenton氧化法基础上发展起来的Fenton氧化法联用技术扩展了Fenton氧化法的适用范围,提高了Fenton氧化法的处理性能。本文对Fenton氧化法联用技术的研究进展及其在污水处理、土壤修复、污泥减量化等方面的应用进行了全面介绍。     

市政污泥脱水及生物淋滤调理技术综述

随着我国城镇污水处理厂污泥产量的不断增加,污泥的处理处置已成为人们关注的热点问题。实现污泥减量化、稳定化、无害化与资源化是污泥处理处置的终极目标。分析了市政污泥脱水的主要影响因素,概述了目前广泛采用的市政污泥脱水预处理技术,详细介绍了生物淋滤技术及其对污泥脱水性能的影响,并对存在的问题及发展方向进行探讨。     

Fenton试剂对剩余污泥脱水性能的改善

研究了利用Fenton试剂调理城市污水处理厂剩余污泥,通过测定污泥毛细吸水时间(CST)、污泥比阻(SRF)和泥饼含水率来表征污泥脱水性能的变化,分别考察了污泥初始pH、H2O2投加量、H2O2/Fe2+、反应温度和反应时间对污泥调理效果的影响。综合考虑,确定Fenton调理污泥的最佳条件为:pH=3、抽滤脱水和离心脱水H2O2最佳投加量分别为3 g/L和9 g/L、H2O2/Fe2(+质量比)最佳范围为8～12、反应温度50℃、反应时间60 min。对污泥离心上清液中胞外聚合物(EPS)含量的研究表明,Fenton调理后污泥上清液中蛋白质和多糖含量有大幅升高,说明Fenton试剂能有效氧化破解EPS,从而提高污泥的絮凝性,改善污泥的脱水性能。Fenton氧化后污泥颗粒粒径变小,比表面积增大。     

Fenton试剂预氧化对污泥脱水效果影响的研究

采用Fenton试剂对100mL含水率为95%的剩余污泥进行预氧化,探究其对污泥脱水效果的影响。结果表明:Fenton试剂预氧化污泥的最佳条件为:pH=3、反应时间60min、H_2O_2投加量为6g、H_2O_2与Fe~(2+)的质量比为12/1。分别将原污泥和预氧化的污泥在0.04MPa真空度下进行抽滤脱水,原污泥含水率降到74.3%,预氧化的污泥含水率降到了64.5%,说明Fenton试剂预氧化能够有效改善污泥的脱水效果。     

水热电解质法污泥脱水技术

活性污泥法广泛应用于市政和工业废水处理,处理过程中产生大量的活性污泥,污泥脱水性能差,成为制约污泥处理处置的瓶颈。水热电解质法是一种有效的强化污泥脱水技术,工艺、设备简单,效果相对明显。综述了水热电解质法污泥脱水技术的研究进展,重点就温度、电解质种类和浓度等关键因素对污泥脱水性能的影响进行了探讨,并对该技术需要解决的问题和应用前景进行了展望。     

白龙港污泥暂存库区污泥压滤液处理

我国市政污水处理厂脱水污泥的主要处置方式为填埋,垃圾填埋场接受市政脱水污泥时,会设置污泥暂存坑存放市政污泥.白龙港污水处理厂污泥暂存场中长期存有污泥,大量雨水渗入致使污泥填埋的稳定性大幅降低.取出稳定化的污泥进行脱水,可进一步减量污泥,又可腾出大量污泥填埋空间.对暂存库区污泥进行脱水时,会产生大量的高氨氮压滤液.为消除污泥储坑中污泥及其产生渗滤液对周围环境的危害,需同步处理污泥和渗滤液,以消除污泥储坑对周围环境产生的危害.文中对白龙港污泥暂存场中所产生的污泥压滤液进行试验处理,经混凝沉淀、吹脱和氧化工艺处理后,出水水质可达到下水道纳管标准.通过开展填埋污泥暂存库区污泥处置成套技术研究与示范,为白龙港污泥暂存库区污泥消纳处理提供技术支撑.     

污泥深度脱水技术研究进展

随着经济的发展和国民生活水平的提高,污水污泥的排放量逐年增加,环境问题愈发严重,污泥的处理处置成为焦点问题,污泥脱水是制约污泥处置处理进一步发展的关键。本文针对目前污泥深度脱水技术开展,首先简述了不同来源污泥的分类及其基本特性,然后重点阐述了不同污泥预处理技术,分析了各污泥深度脱水技术作用机理,并对各自脱水效果及优缺点进行比较分析。结果表明,物理法中水热预处理对污泥的可脱水程度提升最大。较低声强、短时间的超声波处理对污泥脱水性能有着明显的改善。化学法在污泥过滤性能以及脱水速率方面有很大优势,酸碱处理后污泥zeta电位上升,污泥过滤性能及脱水速率得到改善。高级氧化法处理后污泥脱水效果高于酸碱处理,微生物细胞被溶解释放出有机物,可脱水程度改善。生物法处理污泥除改善污泥脱水性能外,还有对环境污染小等特点,但耗时较长。最后对污泥的后续脱水工艺进行综述,介绍了现存的主流脱水工艺,包括机械脱水、热干化技术、水热脱水工艺等;并针对不同的污泥后续利用方法,选取合适的预处理技术,提出相应优化的污泥处理工艺流程。     

Incorporation of rapid thermal conditioning into a wastewater treatment plant

Rapid thermal conditioning is a developing technology recently applied to sludge treatment. Sludge is heated rapidly to reaction temperature (up to about 220°C) and quenched after 10 to 30 s. This process reduces the amount of biosolids requiring land disposal by increasing its biodegradability and dewaterability. Rapid thermal conditioning may be incorporated into a wastewater treatment plant where, combined with anaerobic digestion, it would reduce the quantity of biosolids requiring disposal, eliminate the need for polymer coagulant, improve dewaterability, increase methane production, and further reduce the concentration of pathogens. Also, the odor problem associated with traditional thermal conditioning processes is largely minimized. Pilot scale equipment was used to assess the process and provide design parameters for scale-up. Introduction of the process into an existing municipal wastewater treatment plant was then evaluated using the Wards Island Water Pollution Control Plant of New York City as an example. Two alternative flow sheets are shown together with preliminary engineering designs. Cost estimates for these alternatives show a substantial advantage in comparison to present plant operation.     

Optimization Study of Municipal Sludge Conditioning,Filtering, and Expressing Dewatering by Partial Least Squares Regression

The effect of different conditioner doses and different applied pressures on the dewaterability of municipal sludge during the filtration and expression stage was assessed using a series of experiments referred to as a uniform design. The relative importance of conditioner dose and applied pressure on the dewatering characteristics of municipal sludge was evaluated with a quadratic model using partial least squares (PLS) regression analysis. It was shown that the developed quadratic model was able to accurately predict the dewatering characteristics during the whole process. It was further shown that lime as a physical conditioner had the most significant impact on filtration rate, expression rate, cake dry solids content, net sludge solids yield, and total cycle time. Aluminum polychloride as the inorganic flocculant had a quite complex effect although not as significant as lime. Filtration pressure had only a slight effect on dewaterability of the municipal sludge, though higher feeding pressure was needed in order to enhance the total feeding amount. Furthermore, expression pressure was only of benefit to cake dry solids content and expression rate and failed to improve other dewatering characteristics of the municipal sludge.     

Sewage Sludge Electro-Dewatering Treatment—A Review

Purification of municipal wastewater generates huge amounts of sewage sludge, which contains large quantities of water, biomass, and extracellular polymeric substances. It is widely known that sewage sludge usually has a poor dewaterability. A large amount of water in sludge directly translates into high transport and handling costs; therefore, sludge treatment and disposal usually requires over 50% of the operation budget for wastewater treatment plants. The application of a low electric field through the sludge segment, called electro-dewatering, is considered to improve the liquid–solid separation, resulting in low water content in the sludge cake. However, prediction of dewatering enhancement for sewage sludge, in particular, offers a challenge due to variations in sludge pretreatment practices and the lack of harmonized testing methodologies. In this review article, the aspects that have an effect on sewage sludge electro-dewatering and its feasibility are discussed in the light of recent technological developments. It was found that electro-dewatering has several potential benefits, such as removal of pathogens, reduction in energy and transportation costs, and prevention of filter fouling.     

MOFs及其衍生物在非均相Fenton催化中应用的研究进展

非均相Fenton氧化技术作为高级氧化工艺（AOP）的一种,能够有效解决传统Fenton技术适用pH范围窄、易产生铁污泥、催化剂难回收等问题,但其反应活性受催化剂材料限制。本文介绍了近几年金属有机骨架（MOFs）及其衍生物在非均相Fenton技术中的应用成果,分析了MOFs及其衍生物比表面积大、活性位点丰富、易于结构调控等优点在改善非均相Fenton技术活性位点不足、Fe²⁺/Fe³⁺循环效率低、传质效率差等问题时所发挥的作用,综述了对MOFs进行改性设计以获得高活性催化剂的研究进展,总结了当前应用MOFs作为催化剂材料仍存在的缺陷。未来MOFs催化剂的研究应集中在高活性改性设计及商业化应用这两方面。     

污泥热水解处理技术研究进展

活性污泥法的广泛应用于市政和工业废水处理,剩余污泥的处理成为污水处理厂面临的一个严峻问题,而且处置成本已占污水处理总成本的50%～60%。本文着重阐述热预处理剩余污泥以提高污泥脱水性和污泥的消化性能,以及对商业上应用的主要污泥热水解过程(Porteous,Zimpro和Cambi)及污泥热处理最优条件进行介绍。     

工业有机废水深度处理：非均相Fenton催化剂研究进展

在众多水处理技术中,Fenton法能产生具有强氧化性的羟基自由基（·OH）,被认为是处理水中难生物降解有机污染物的有效方法。但是,传统的均相Fenton技术存在响应pH范围窄、催化剂活性组分不易回收分离、产生的铁泥会造成二次污染等问题,而非均相Fenton技术则可有效克服上述缺陷并具有良好工业应用前景。本文评述了Fenton反应,尤其是非均相Fenton技术近年来的发展情况,主要综述了其反应机理、反应活性的影响因素以及非均相Fenton催化剂研究现状。重点结合构-效关系、合成方法与反应机制探讨了国内外铁基与非铁基金属催化剂与碳基催化剂的发展进程以及其对于难降解有机物的处理效果。并总结了双氧水利用率、催化剂稳定性、反应的控速环节对非均相Fenton催化剂体系应用的影响与限制,为进一步改进催化剂的设计与制备方法提供了思路。     

Effects of Acidification on Dewaterability and Aluminum Concentration of Alum Sludge

This study utilizes the Terzaghi-Voigt model to characterize the effects of acidification on the dewaterability of alum sludge. Alum sludge, which was obtained from the sedimentation basins of a water treatment plant using poly aluminum chloride as coagulant, was acidified to different pH levels with sulfuric acid. The dewaterability of the acidified sludge was characterized by expression tests. The results show dewaterability enhancement was insignificant until pH was below 4. Further improvement in dewaterability can be achieved by polymer conditioning. The Terzaghi-Voigt model can be applied to explain the difference in dewaterability between acidified and original sludges. Results also show dissolved aluminum concentrations were controlled by minerals in the influent rather than amorphous aluminum hydroxide.     

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).     

污泥水热处理制备清洁燃料的研究进展

目前,庞大的污泥产生量是困扰工业与市政工程的一个主要问题,对其减量化与能源化利用是污泥处置的关键。其中,水热技术是一种可直接并有效利用污泥等高含水率废弃物的处理手段。本文首先介绍了污泥的特点以及处理现状,然后总结了国内外近年来关于污泥水热处理工艺的发展历程与工业应用情况。此外,着重讨论了水热处理对污泥能源化利用的各项优势,包括：降低NO_x、酸性气体与飞灰等污染物的排放,固定污泥重金属,改善污泥燃料性能,提高污泥脱水性能以及降低其处理成本等。同时,针对不同种类污泥的不同组分在水热处理过程中的反应过程与影响因素进行了详细讨论。最后,对于污泥水热处理能源化利用的发展前景作出展望,指出深入研究污泥与其他废弃物混合水热或焚烧过程中的协同作用是制备高品质燃料的重要途径。     

微波辐射对脱水城市污泥穿透性和脱水性的影响

研究了频率2450 MHz、功率500 W的微波在脱水城市污泥中的穿透性及辐射过程中污泥脱水性的变化. 结果表明,微波的穿透深度为8.7 mm,适宜的辐射可显著提高污泥的脱水性. 微波辐射5 min,上层容器中污泥离心后含水率由80.61%降至75.09%. 当温度高于约60℃时,污泥中微生物细胞开始大量破碎,胞内水释出,离心后含水率随温度升高而降低;高于88℃时,胞外聚合物含量无明显增加而亲水性下降,污泥脱水性迅速改善.