微生物絮凝剂的絮凝性能研究

研究了微生物絮凝剂“Dtjm-1”的絮凝性能，通过改变废水初始pH值，调整废水中阳离子种类、阳离子浓度及改变发酵液的离心条件和投加体积，得出絮凝剂“Dtjm-1”的最佳絮凝条件为：废水pH值7.2-8.0；能较好促进絮凝的离子有Al^3 ,Ca^2 ,它们最适合的浓度为每升废水中加入0．75－1g/L；发酵液的投加体积为（0.075-0.080):1(体积比）；发酵液较好的离心条件为n=4000r/min,t=30min。通过不同废水絮凝效果试验表明，得出絮凝剂“Dtjm-1”具有很好的絮凝作用和脱色性能。     

微生物絮凝剂研究和应用进展

微生物絮凝剂是由微生物产生的有絮凝活性的代谢产物．由于微生物絮凝剂具有降解性能好、应用广泛、成本低、操作简单及不会导致二次污染等优点，正日益引起人们的广泛重视。本文综述了微生物絮凝剂的开发现状和应用进展，系统介绍了微生物絮凝剂产生的条件、絮凝机理以及影响其絮凝活性的因素，着重列举了微生物絮凝剂在水处理领域中的应用实例。最后对微生物絮凝剂的发展趋势进行了展望。     

化学絮凝法处理实验室废水中化学耗氧量的研究

以碱式氯化铝和硫酸亚铁并用,处理实验室废水中化学耗氧量的最佳条件是每升废水中ＦｅＳＯ４和Ａｌ（ＯＨ）２Ｃｌ分别为３０ｍｇ和１０ｍｇ,废水中的ＰＨ为５－９,搅拌时间为１５分钟,澄清时间为１小时。该法对处理耗氧量ＣＯＤ＾①有显著效果,经处理后的废水可达到工业废水的排放标准,因此这是一种经济有效而又简便的方法。     

硅酸盐细菌GY03菌株的絮凝特性

从土壤中筛选分离到一株硅酸盐细菌GY03菌株，对其絮凝特性进行了研究。结果表明，GY03菌株营养要求简单，在生长的同时合成胞外高聚物，具有良好的絮凝性能。GY03菌株所产絮凝物质有88％以上分布在细胞表面，该絮凝剂的絮凝活性随菌体生长量的增加而同步增高，不同金属离子对GY03菌株絮凝活性有影响。实验条件下，1h内GY03菌株所产生的微生物絮凝剂对高岭土悬浮液絮凝率为78％，经放置24h后最高絮凝率可达98％，对制药废水浊度去除率为78．1％～94．7％，COD去除率为48．0％-87．5％，生活污水浊度去除率为85．3％～92．5％，对墨汁溶液的脱色率为53．2％以上。因而认为该菌株是一种很有应用前景的絮凝剂产生菌。     

复合型微生物絮凝剂产生菌YL3的优化条件

通过培养基成分减少、碳氮源影响因素、培养基成分含量优化、培养时外界条件等系列实验,对复合型微生物絮凝剂产生菌YL3的培养条件进行了优化。研究结果表明:该菌的培养条件受以上各因素的影响,培养基的最佳组成为葡萄糖2.0 g,K2HPO4.3H2O 5.0 g,KH2PO41.0 g,MgSO4.7H2O 0.20g,(NH4)2SO4.7H2O 0.20 g,蒸馏水1 L,初始pH=7;培养基的外部培养条件为灭菌压力0.06 MPa,温度20~30℃,振荡转速100~140 r/min。降低了复合型微生物絮凝剂的转化成本,提高了该菌的絮凝能力。     

无机高分子絮凝剂絮凝机制的研究进展

近年来无机高分子絮凝剂的研究已成为水处理药剂研究的热点。本文概述近年来无机高分子絮凝剂絮凝机理的研究进展 ,包括我们所最近研制的三系列含水聚硅酸铝铁钠废水净化剂 ,它们的优缺点及其絮凝机理。重点阐明研制絮凝剂时通常采用共存阴离子和活性硅酸与铝盐或 /和铁盐的聚合作用 ,并探索絮凝剂中各组分对絮凝剂的絮凝效果的贡献。     

高岭土颗粒的絮凝沉降试验研究

粘性细颗粒泥沙在盐水中会产生絮凝。影响其絮凝的因素很多,矿物组成是其中的一个重要因素。选取高岭土作为研究对象,通过一系列试验得出所研究的高岭土的中值粒径为0.0084mm,最佳絮凝盐度为13‰,起动流速为8.5 cm/s~10 cm/s,由试验数据分析得出高岭土在不同流速条件下的淤积量以及淤积百分比,既而确定其不淤流速为40 cm/s。     

深圳市电镀废水微生物处理初步研究

利用一株絮凝效果好的胶质芽胞杆菌所产的微生物絮凝剂进行了深圳市较具代表性电镀废水絮凝性实验。结果表明,微生物絮凝剂有较强的吸附作用,能降低电镀废水中重金属离子的浓度,对废水pH值有一定的调节作用。实验确定了处理综合电镀废水中重金属的条件,初步提出电镀废水的处理和回用工艺。     

微生物絮凝剂投加方式对好氧颗粒污泥性能的影响

为提高好氧污泥颗粒化速度, 采用微生物絮凝剂, 探讨在好氧颗粒污泥培养过程中微生物絮凝剂的投加方式对颗粒污泥理化性能及生物降解效能的影响。结果表明:微生物絮凝剂每隔2、3、5、7 d投加一次时, 均可培养出成熟的好氧颗粒污泥, 微生物絮凝剂的投加方式对好氧污泥颗粒化的影响较显著;微生物絮凝剂最佳投加方式为每5天投加一次, 此时颗粒化速度快, 颗粒形成时间由未投加的60 d缩短为42 d, 好氧颗粒污泥疏水性好, 污泥体积指数稳定在40 mL/g左右, 沉降速度达35.06 m/h, COD、氨氮和总磷的去除率分别为96.55%、93.29%和87.29%。     

Non-parallelism between the effect of microbial flocculants on sewerage disposal and the flocculation rate

1 IntroductionMicrobial flocculant (MBF) is one of the naturalmacromolecular organic compounds, which is producedby some microorganisms and has a high flocculationfunction ( Cheng Wen et al., 2003). It has beencalled“the third-generation flocculant”beca…     

流化床混凝装置中多级速度梯度的建立及其对混凝反应的影响

利用不同性质颗粒在流化状态下可实现自然水力分级的特征,在流化床反应器中沿水流方向实现了多级速度梯度的建立。在研究流化床混凝反应器的混凝动力学特征基础上,探讨了以800 μm和1 200 μm树脂颗粒为固相的多级速度梯度流化床（MGF）的速度梯度分布特征、混凝效率和絮体形态特征,并与以1 200 μm树脂颗粒为固相的单级速度梯度流化床（SGF）进行了对比研究。结果表明：与单级速度梯度相比,多级速度梯度可为胶体或微颗粒的高效碰撞和絮体再增长创造更适宜的环境,有助于形成尺寸更大、密度更大的絮体,提高了絮体的可沉降性;MGF在处理人工配置的高岭土悬浊液和分散红染料废水时,混凝效率比SGF分别提高了2%～4%和7%～20%。     

CaO添加顺序对废弃泥浆絮凝效果的影响

针对温州某钻孔灌注桩废弃泥浆进行了沉降柱试验和颗粒分析实验,研究有机絮凝剂APAM以及无机絮凝剂CaO对泥浆沉降性能和颗粒粒径的影响,着重探究了无机絮凝剂CaO的不同添加顺序对有机絮凝剂APAM絮凝效果的影响。结果表明：在较少APAM添加量(10 mL)下后添加CaO能增大泥浆的初始沉降量;先添加CaO再添加APAM,不利于APAM絮凝作用的发挥;后添加CaO的情况下,CaO对于最终的絮体粒径的影响主要取决于絮体本身的强度及搅拌强度。     

AlCl3对细颗粒泥沙絮凝沉降的影响

铝类絮凝剂对细颗粒泥沙絮凝沉降有重要作用,常应用于浑水澄清、农业污水处理等研究中。在AlCl₃浓度为0～1.7mmol/L,泥沙浓度为10g/L时,用吸管法研究了AlCl₃对细颗粒泥沙絮凝沉降的影响,结果表明:在液面下同一深度,泥沙浓度随时间呈指数衰减;悬液经多次搅拌后再沉降,其沉速减缓;当AlCl₃浓度为0.9～1.7mmol/L时,出现明显的清浑水交界面,交界面随时间等速下降,平均沉速为4.756cm/min,对应的絮团平均粒径为0.0315mm;土娄土絮凝临界粒径为0.027mm。     

Micro-properties of coal aggregates: Implications on hyperbaric filtration performance for coal dewatering

The recovery of ultrafine coal can be enhanced significantly by flocculating the particles prior to dewatering. It is thus crucial to be able to quantify the effects of aggregated particles on the separation efficiency, of which they are still not fully understood. This study focused on the relationship between the micro-properties (size, structure, and strength) of flocculated coal particles and the characteristics of filter cakes obtained through hyperbaric filtration. Tools such as small angle light scattering and confocal scanning laser microscopy were used to determine the aggregate structure. The comparative bond strength of aggregates generated under different flocculation conditions was measured through a non-dimensional approach. The effects of these properties on specific cake resistance, saturation, and moisture content, as indicative of the filtration performance, were observed. It was found that flocs generated using a moderate amount of flocculant dosage (60–100 g of polymer/tonne of coal) for this ultrafine coal (97% < 35 μm) optimised the properties of dewatered filter cakes. Although cakes composed of larger and stronger aggregates with more flocculant were found to have higher porosity, the effects on specific cake resistance and cake saturation were detrimental, possibly due to the increasing proportion of intra-aggregate pores that were harder to dewater. The trend was less noticeable at low filtration pressures where most of the dewatering occurred within the larger capillaries of the inter-aggregate zones. In addition, the presence of polymer molecules was responsible in absorbing residual moisture that could not be removed through mechanical means. Through a series of tests using pre-formed filter cakes, the amount of moisture retained by the flocculant was quantified to be approximately 10.2 mg of water for every addition of 1 g of polymer/tonne of coal, calculated per 100 g of filter cake produced from hyperbaric filtration in this case.     

Study on the Flocculability of Metal Ions by Bacillus Mucilaginosus GY03 Strain

Inrecentyears,withtherapiddevelopmentofindustrialeconomy ,wastewaterisdischargedinhugevolumeandtheaccumulationofheavymetalionsinsoilsandwatersourcesisspeededuprapidly .Asaresult,waterpollutionhasbecomeadailydeterioratingproblem .Heavymetalsareeasytoenterthefoodchain ,therebyconstitutingagreatthreattothehealthofanimalsandhu manbeings .Therefore,howtoeffectivelyhandleheavymetalpollutionhasbecomeacommonat tractionformankind .Theroutineheavymetaltreatmentmethodsaremainlythechemical,phys icalandphy…     

Flocculation improves uptake of Sr and Cs from radioactive effluents

This paper presents the results of investigation on uptake of radioactive species ⁹⁰Sr and ¹³⁷Cs present in the liquid effluents from nuclear processing plants. Chemical precipitation process is adopted to remove radioactivity from the effluents with low and intermediate level of activity. In this process, radioactive ⁹⁰Sr and ¹³⁷Cs are co-precipitated along with copper ferrocyanide, ferric hydroxide and either calcium phosphate or barium sulphate. These precipitates being fine in size require flocculation for enhanced settling rate in clarifier/thickener. The flocculation by some selected high molecular weight polyacrylamide based polymers has improved the uptake of radioactive metal ions. The adsorption of these radioactive species has been found to increase in the presence of these flocculants thereby improving the decontamination factor (DF). While flocculating the precipitates, there may be some complex formation with Sr²⁺/Cs⁺, flocculant and the substrate. This has enhanced the uptake of the radioactive metal ions from the liquid component. The plant trials have indicated the improvement of DF value due to flocculation by cationic flocculant.     

垃圾渗滤液污染场地NO_3~-、PO_4~(3-)和SO_4~(2-)对微生物活性的影响

通过实验研究垃圾渗滤液污染场地N、S、P和湿度等因素对微生物活性的影响.结果表明：同时添加N和P后,土壤和细砂中微生物活性分别在第7 天和第14 天达到最大值0.685和0.588,有机质质量分数分别降低了10.97%和22.1%,平均降解速率分别为0.405和0.190 mg/(kg·d);添加NO_3~-后,土壤和细砂中有机质质量分数分别减少了10.3%和28.9%;添加SO_4~(2-)后,土壤和细砂中有机质质量分数分别减少了8.87%和28.4%;另外,湿度为50%和60%时,土壤中微生物活性的最大值分别为0.259和0.266,有机质平均分解速率分别为0.195和0.305 mg/(kg·d).因此,N、S、P和湿度对地下环境中微生物的活性有重要影响.