基于絮凝调理技术强化污泥脱水性能的研究进展

对污泥进行调理改性,提升污泥脱水性能是实现污泥妥善处置和资源化利用的重要前置条件。基于絮凝原理的调理技术效果显著,成本可控,是改善污泥脱水性能的最可靠和应用最广泛的技术之一。此外,絮凝联合调理技术能发挥协同作用,功能特性更加完备,是当下污泥脱水的研究热点。介绍了污泥处理处置现状及污泥脱水的技术难点,阐述了不同种类絮凝剂和絮凝联合调理技术的作用机理及应用效果,以期为利用絮凝调理技术强化污泥脱水性能提供理论依据和应用参考。     

聚合絮凝剂及污泥脱水方法

本发明提供一种用于污泥脱水的絮凝剂，产生的絮片在絮凝浓度、过滤速度和含水量上具有很好的平衡。同时提供了使用该絮凝剂进行污泥脱水的方法。该絮凝剂属于聚合物絮凝剂，共聚物中包括烷氧基烷基单元或一种聚环氧烷基单元，还可以包括水溶性单体单元：污泥脱水的方法包括，在投加无机絮凝剂或有机阳离子化合物后，向污泥中投加聚合物絮凝荆进行污泥脱水。     

絮凝理论与应用

论述了絮凝剂的反应机理、各种影响絮凝剂效果的因素、絮凝品种、用量、分子量和污泥粒度、浓度、PH值与操作温度对絮凝效果的影响、同时描述了絮凝剂的溶解方法、投加方法对处理效果的影响。对污水污泥处理工程的设计者、操作者都有重要指导意义。     

污泥调理剂与有机高分子絮凝剂联合作用对污泥脱水性能影响的研究

结合污泥调理剂和有机高分子絮凝剂在调理活性污泥中体现出的优缺点,将两者联合用于活性污泥的调理。先后投加不同量的调理剂和絮凝剂于活性污泥中,研究其对污泥絮体特征和脱水性能的影响。结果表明,当两者投加量分别为1%和0.5%时,污泥泥饼含水率降到最低,为75.41%,且污泥过滤性能得到较好的改善。这是由于调理剂的投加改变了污泥絮体结构,导致胞外聚合物（EPS）的分布发生变化,改善了污泥的脱水性能,絮体颗粒粒径减小,而投加有机高分子絮凝剂使得污泥絮体重新絮凝,从而提高脱水速度。     

壳聚糖絮凝剂的投加量对污泥脱水性能的影响

通过污泥比阻的测定,分析絮凝剂剂量对污泥脱水性能的影响。同时对三氯化铝、阳离子聚丙烯酰胺、壳聚糖以及复合絮凝剂的絮凝效果进行比较。结果表明,无论是无机絮凝剂和有机絮凝剂都存在最佳剂量,小于或大于最佳投加量,絮凝效果都不好。阳离子聚丙烯酰胺(CPAM)、壳聚糖、三氯化铝的最佳投加质量浓度分别为0．2g/L、10g/L、35g/L。与三氯化铝相比,阳离子聚丙烯酰胺的药剂消耗量要低得多。壳聚糖与CPAM相比,在达到相同的絮凝效果时,壳聚糖的用量大于CPAM的用量。将壳聚糖与氯化铝复合,用两段法应用于污泥调理,研究这种复合絮凝剂的脱水性能,实验表明壳聚糖和三氯化铝复合,能大大提高污泥的脱水性能。     

炼油废水生化污泥絮凝处理试验

针对炼油废水生化污泥含水率高、脱水困难等问题,进行了污泥絮凝处理试验研究。试验结果表明阳离子聚丙烯酰胺(CPAM)是炼油废水生化污泥处理的理想絮凝剂。生化污泥经絮凝处理后,污泥具有良好的沉降性能和脱水性能,过滤脱水后,污泥的含水率可从94%~99.8%降低到70%~85%,降低了污泥的含水率和体积,便于运输和最终处置。     

高分子污泥脱水絮凝剂的研究进展

絮凝剂在污泥处理处置中应用越来越广泛,随着污泥处理处置问题的备受关注,污泥脱水絮凝剂也在不断的发展。文章综述了常用的几种污泥调理方法以及近年来无机高分子污泥脱水絮凝剂、有机高分子污泥脱水絮凝剂、无机-有机复合高分子脱水絮凝剂、天然高分子污泥脱水絮凝剂的研究进展;同时揭示了未来高分子污泥脱水絮凝剂的发展趋势。     

阳离子絮凝剂PDA的合成与应用——对再生造纸废水的污泥脱水处理

研究了阳离子聚丙烯酰胺絮凝剂PDA对一种废纸再生造纸废水中的污泥的絮凝脱水处理过程，探讨了絮凝剂PDA的投加量，电荷密度，平均相对分子质量对絮凝脱水效果的影响，并比较了各种不同絮凝剂的处理效果，研究结果表明，絮凝剂PDA的电荷密度越大，相对分子质量越高，其絮凝脱水效果越好，在与无机絮凝剂PAC复配使用的相同条件下，实验室自制的絮凝剂PDA的絮凝脱水效果优于其他作对比的市售多种阳离子聚丙烯酰胺类絮凝剂。     

树叶粉对污泥脱水性能的影响研究

城市污水处理厂通常采用聚丙烯酰胺或铁盐作为污水处理后污泥的脱水调理剂,然而大量化学絮凝剂的使用不利于后期污泥的资源化利用。本研究首次采用树叶粉作为新型"物理调理剂",探究树叶粉及树叶粉-Fe_2(SO_4)_3、树叶粉-PAM联合调理,对污泥脱水性能的影响规律。结果表明,使用树叶粉调理能够在一定程度改善污泥的脱水性能;树叶粉与化学絮凝剂联合调理污泥,能够充分发挥协同作用,脱水效果优于单独使用树叶粉或絮凝剂的调理效果。     

微细粒浮选精煤絮凝脱水试验研究

为改善浮选精煤压滤过程中微细颗粒煤的损失问题,提出了絮凝压滤脱水工艺,探索了絮凝剂类型及用量、凝聚剂类型及用量对浮选精煤絮凝沉降效果的影响;试验表明,分子量1 000万的阴离子型絮凝剂的效果优于其他絮凝剂,凝聚剂中明矾的凝聚效果优于聚合氯化铝和氯化钙;在浮选精煤煤浆浓度为150 g/L,最佳用量絮凝剂为1.6 mg/L、凝聚剂为400 mg/L条件下,浮选精煤絮凝沉降上清液浊度可降至16.81 NTU,浮选精煤絮凝压滤脱水的精煤回收率比直接压滤脱水提升8.9个百分点,微细粒精煤损失减少61.49%,滤饼水分降低1.67个百分点。     

Water Soluble Polymer Flocculants: Synthesis,Characterization, and Performance Assessment

Water soluble polymer flocculants are important constituents of solid–liquid separation units for the treatment of a variety of process‐affected effluents. The systematic development of a flocculant relies on a good understanding of flocculation process, polymer synthesis, polymer characterization, and, not the least, flocculation performance assessment as desired for a particular treatment process, all of which are essential to establish meaningful relationships between flocculant microstructure and flocculation efficiency. The aim of this article is to communicate the bigger picture of this research area to the readers. The recent advances in the application of bio/natural, synthetic, and stimuli‐responsive flocculants are reviewed. Then, the basic polymer reaction engineering tools to control the microstructure of flocculants are provided and the techniques for the quantification of flocculant microstructure are concisely discussed. This is followed by a review of the methods used for the characterization of particle‐polymer force measurement, and flocculation/dewatering assessment with attention to the characterization of aggregate structures.     

基于介观尺度模拟的污泥絮凝形态及机理

用介观动力学的方法对胶体颗粒与高分子链的絮凝过程进行了模型研究,并根据模型结果对污泥和阳离子聚丙烯酰胺的絮凝过程和污泥脱水机理进行有针对性的探讨。通过建立粗粒化模型和经验势函数力场有效模拟了负电性的胶体颗粒与阳离子型高分子链的絮凝过程;模拟得出了絮凝的外观形态,证明了高分子链对胶体颗粒的桥接作用以及表面电荷的中和作用对絮凝的影响;并对絮凝反应过程的体系势能变化进行了研究。对实际污泥胶体颗粒和阳离子聚丙烯酰胺溶液拍摄了电镜图片并观察了其吸附过程;最后研究了高分子链离子度对溶液体系絮凝的影响,验证了离子度的增加有利于絮凝体的形成,但同时也由于絮凝体结构的复杂而对污泥脱水造成了一定的不利影响。     

Optimization of slurry flocculation and dewatering based on electrokinetic and rheological phenomena

The use of chemical additives known as conditioners or flocculants is crucial in assuring the proper functioning of many solid-liquid separation processes, and dewatering in particular. The additive used is often a water soluble polymer with high molecular mass, strong adsorptive properties, and often a large amount of ionic charge. The type of polymer used, and its exact dose, may change with process or flow conditions, and these changes may lead to poor operation. However, advances in the understanding of conditioning and flocculation of slurries and sludges now make it possible to develop scientifically-based strategies for optimizing these processes. These advances have utilized new characterization methods that allow insight into fundamental aspects of the process. In several cases the analyses employed are also amenable to continuous reading, and therefore to automatic feedback control of the process. This paper describes these advances and suggests conditioning and flocculation control strategies that will allow optimization of subsequent dewatering processes. The research advances described are: (1) use of the streaming current detector for monitoring and controlling dewaterability; (2) evaluation of floc strength by streaming current and rheological and methods; (3) use of rheological characteristics of conditioned residuals for dose control; (4) application of liquid-stream viscosity for polymer dose monitoring and control; and (5) quantification and verification of mixing conditions in conditioning processes, and use for mixing similitude. These developments should aid in the proper initial selection of a conditioner product (flocculant) and its dose, and allow optimization based on continuous monitoring if the sludge conditions vary significantly over time.     

Sludge Dewatering and Aggregate Formation Effects through Taylor Vortex Assisted Flocculation

Abstract

For polymer induced flocculation processes, the effects of flow patterns in a gap of a conical stirrer on aggregate formation and subsequent sludge dewatering efficiency were analysed. Different flow regimes were identified by lab scale investigations with model substances and summarized in a Ta and Re number plane. An enhancement of sludge dewaterability for polymer induced flocculation processes was identified through post‐treatment of flocculated sludge aggregates by the specific flow pattern of stable and wavy Taylor vortices. Photo‐optical image analysis of flocculated aggregates shows a clear change of aggregate size distribution with less small particles during aggregate forming by Taylor vortices compared to classical flocculation procedure by stirrer. Results from technical scale dewatering analyses confirmed enhancement of sludge dewatering efficiency for six different dewatering machines using the identified wavy and stable Taylor vortex flow pattern regime.     

絮凝技术在化工污水处理中的应用

对不同种类的絮凝剂在不同试验条件下得到的絮凝现象进行观察,絮凝后的污水通过带式压榨过滤机过滤,根据过滤前后污泥性质的变化选择出最佳的絮凝剂及使用条件。     

1，3-丙二醇发酵液的絮凝除菌研究

研究了用絮凝法处理1,3-丙二醇发酵液,选用10种絮凝剂,以FR值为指标,考察了各种絮凝剂的絮凝效果,对初选出的5种絮凝剂进行复合絮凝,选出了适合于1,3-丙二醇发酵液体系的复合絮凝剂。通过单纯型寻优法确定了最佳絮凝工艺条件,絮凝率达98%以上,且絮凝后上清液清澈、透明,过滤效果良好。     

超声辅助絮凝强化污染底泥土工管袋脱水减容

将超声处理结合絮凝剂用于土工管袋脱水减容.以滤饼含水质量分数为优化指标,考察超声处理与添加絮凝剂的顺序对脱水性能的影响,并考察了超声处理的最优操作条件.结果表明:先添加絮凝剂再进行超声作用可取得较好的脱水效果,当絮凝剂的投加量(质量分数)为5‰(以干基计),超声波的能量密度为0.5 W/mL,作用时间为10 s,脱水效...     

絮凝反应池中流体的CFD模拟及应用性能

絮凝反应是原水预处理工艺(混合-反应-沉淀)的重要环节,对整个工艺过程的水处理效果影响极大。本文针对絮凝反应过程中絮体颗粒生长所需的水力学条件,采用计算流体力学(CFD)软件分析了所设计搅拌絮凝反应池运行的可行性,通过控制絮体颗粒生长的流场,使絮体在其中可以生长至合适的尺度。研究结果表明,采用优化之后的反应设备,可以节约絮凝剂用量约20%,降低了生产费用,避免过量絮凝剂对水体造成的二次污染,并且提高了出水效果。     

2,3-丁二醇的絮凝预处理研究

为使生物法制备2,3-丁二醇的后续分离纯化过程顺利进行,研究了絮凝法预处理2,3-丁二醇发酵液。选用10种絮凝剂,以絮凝率和蛋白去除率为指标,分别考察了絮凝剂、质量浓度、pH值、温度和搅拌时间等条件对2,3-丁二醇发酵液的絮凝效果、浓度及后续萃取过程的影响,得出较优絮凝条件:以氯化铁为絮凝剂,质量浓度为23 g/L,pH值5.1,温度为20—50℃,搅拌时间15 m in,静置20 m in。在此工艺条件下,2,3-丁二醇的絮凝率和蛋白去除率均可高达98%以上,为后续的分离纯化过程奠定基础。