Activated Sludge Ozonation to Reduce Sludge Production in MBR

The total experimental period was divided into two stages. At the first stage, a series of batch studies were carried out to get an understanding of the effect of ozouation on sludge properties. At the following stages, three MBRs with different amounts of activated sludge to be ozonated were run in parallel for a long period to evaluate the influence of sludge ozonation on sludge yield and permeate quality. Through batch study, it was found that ozone could disrupt the cell walls and caused the release of plasm from the cells, then the amounts of soluble organics in the solution increased with ozouation time. With the rise of soluble organics, the amount of soluble organics to be mineralized increased as well, which would reduce the soluble organics content. For the counteraction between these two aspects, a pseudo-balanee could be achieved, and soluble organics would vary in a limited range. Sludge ozonation also increased the contents of nitrogen and phosphorus in the solution. In addition, ozouation was effective in improving sludge settling property. On the basis of batch study, a suitable ozone dosage of 0.16 kgO3/kgMLSS was determined. Three systems were run in parallel for a total period of 39 days, it was demonstrated that a part of activated sludge ozonation could reduce sludge production significantly, and biological perfonnanee of mineralization and nitrification would not be inhibited due to sludge ozouation. Experimental results proved that the combination of ozonation unit with MBR unit could achieve an excellent quality of permeate as well as a small quantity of sludge production, and economic analysis indicated that an additional ozonation operating cost for treatment of both wastewater and sludge was only 0.096Yuan （US$ 0.011,5 ）/m^3 wastewater.     

MBR处理丁基黄药废水启动期好氧活性污泥特性

探讨利用膜生物反应器(MBR)处理丁基黄药(简称黄药)废水时的启动期及好氧活性污泥驯化过程的运行特征,分析其好氧活性污泥的形成过程、形态特征、性质及对污染物的去除机制.以啤酒污水处理曝气池污泥为接种污泥,以乙酸钠和黄药为碳源,培养及驯化絮体污泥.结果表明,MBR系统经过35 d启动及驯化即可达到正常运行状态,絮体污泥的SVI为100 mL/g,MLVSS/MLSS为0.75,生物量大且沉降性良好,COD及黄药去除率分别可以达到80%和90%.絮体污泥的形成及膜的高效截留增强了MBR运行的稳定性,为黄药废水的高效降解提供了保证.     

新型垂直流人工湿地组合工艺处理剩余污泥实验研究

剩余污泥是污水处理过程产生的主要副产品和有机废物,它的处理与处置是污水处理的重要组成部分.通过6个月的实验室模拟,研究了一种新型垂直流人工湿地组合工艺对剩余污泥的脱水和渗滤液的净化效果.结果表明,随着停留时间的增长污泥含水率和挥发性固体呈下降趋势,脱水后污泥含水率为40%,挥发性固体去除率达48.2%.在实验期间,共有392 L新鲜剩余污泥得到处理,获得10.3 L干污泥,污泥体积减小97.4%.湿地床表面污泥以平均每月0.87 cm的速度增厚,到试验结束时为5.23 cm深.组合系统以20.0 L(/m2.d)的污泥负荷间歇进泥方式运行,其污泥渗滤液的TN,TP和COD的平均去除率可分别达75.2%,97.3%和78.4%.结果说明该垂直流人工湿地组合系统可以作为传统污泥处置的一个替代方法,是一种建造简单、维护成本低的生态处理方法.     

Implementing Both Domestic Wastewater Reuse and Sludge Reduction by a Combination of Anaerobic Phase and Membrane bioreactor

The aim of the research was to obtain both an excellent effluent for reuse and a reduced sludge production simultaneously by a combination process of anaerobic phase and Membrane bioreactor （MBR） technology in treating domestic wastewater. During the experimental period of three months, excellent removals for COD, NH3-H, TN were obtained, and mean removals were 91.87%, 96.13%, and 69. 23%, respectively. Whereas, at first 20 days, the removal for TP was only about 15.87%. In the following days, about 30% of raw water was introduced into the anaerobic reactor to supply organics for denitrificatien and release of polyphosphate, then a significant improvement for TP removal was observed, and mean removal of TP increased to 76.35%. During the operational period, it was investigated that the permeate could meet the requirements of several water criteria for reuse except free chlorine, and a mean excess sludge yield coefficient of 0.137 g MLSS/g COD was obtained. Therefore, the predicted goals of permeate for reuse and excess sludge reduction could be both achieved after dosing a certain quantity of disinfectant into the permeate.     

膜生物反应器净化污水的硝化反硝化性能

比较了膜生物反应器(MBR)和传统活性污泥工艺(CAS)在相同运行条件下处理生活污水的硝化和反硝化性能.结果表明,MBR对NH4 -N和TN的去除率分别比CAS高54.8%和37.3%.2种工艺的亚硝化、反硝化作用均呈零级反应,对应降解速率常数MBR分别约为CAS的2.2倍和2.5倍;CAS中硝化作用为零级反应,而MBR中硝化作用随时间推移趋于平缓.MBR中的细菌总数、硝酸菌、亚硝酸菌和反硝化菌数量分别比CAS工艺中相应菌种高1~2个数量级.通过控制曝气强度或减小回流通道断面限制缺氧区溶解氧质量浓度,可提高MBR中的反硝化效果.     

高温厌氧颗粒污泥膨胀床中颗粒污泥的性质分析

考察了高温(55℃)条件下厌氧颗粒污泥膨胀床处理木薯酒精废水的运行特性和颗粒污泥的性质.结果表明,当进水有机负荷(OLR)在15.0 kg.m-3.d-1时,化学需氧量(COD)平均去除率为86.7%,平均产气量为15.1L.d-1.OLR最高可达24.0kg.m-3.d-1,COD平均去除率为88.5%,平均产气量为39.9L.d-1.颗粒污泥的颗粒化率随着运行时间的延长逐渐增加,运行至260d,直径大于2.00mm的颗粒污泥约占32%.颗粒污泥的有机组分主要是碳、氢和氮,无机组分主要是硅、磷、钙和铁.颗粒污泥表面的微生物以丝状菌为主,污泥内核组成可能主要为磷酸钙或碳酸钙等无机质.     

Experimental Study on Minimization of Sludge Production by Ozonation Process

Based on the hypothesis of reducing sludge production under cryptic growth conditions, ozone was used as cell lysis agent to treat excess sludge, and then the ozonated supernatant was returned to. the aeration tank. The results show that COD and NH4+-N removal efficiencies in ozonation process were 87.96% and 84.42%, respectively. Meanwhile, a low excess sludge yield coefficient of 0.113 (g SS/g COD removed) was obtained. Compared with that of the control test, the process configuration decreased the excess sludge production by 51.3%.     

包埋活性污泥和反硝化污泥短程硝化反硝化脱氮

以模拟废水为对象,在传统的流化床反应器内,将活性污泥和经驯化的反硝化污泥按适当比例混合后,用聚乙烯醇(PVA)加适当添加剂将其包埋,并对短程硝化反硝化脱氮进行了研究.结果表明,在进水NH4+-N平均为53.60mg/L,COD为281.19mg/L,HRT12h,调控温度、溶解氧、pH等,出水亚硝化率和TN去除率分别可达95%和85%以上,短程硝化反硝化脱氮较理想.当进水COD含量从150mg/L增加到750mg/L,TN去除率从73.66%提高到96.79%.适合包埋颗粒短程硝化反硝化脱氮的最佳溶解氧浓度约为4.0mg/L.当pH一直维持在8.0左右,温度从30℃降到25℃过程中,短程硝化反硝化并未遭破坏.当温度维持在25℃,pH从8.0降到7.5,连续运行约5个周期后,短程硝化反硝转变为全程的硝化反硝化.     

Process of Waste Sludge Facultative Metabolism

Laboratory-scale experiments were conducted to determine new technology of waste sludge facultative metabolism . 10-L laboratory-scale facultative reactors were operated during 24-hour sludge residence time (SRT) and in room temperature . Results show that the organic matter in waste sludge after hydrolysis-acidification will be reduced by 75.39%, the removal rate of CODcr above 85% . Advantage of the process is hydrolysis-acidification in ambient air temperature as there is no need for facilities to be sealed or heated. In addition, the sludge will be recycled into the wastewater treatment system and finally towards zero-discharge.     

醌指纹技术解析MBR污泥膨胀过程中微生物群落特性

采用膜生物反应(MBR)工艺连续流小试处理生活污水,对其膨胀过程进行机理解析.结合显微观察和醌指纹技术,对活性污泥混合液中的微生物群落结构的生态演替过程进行连续监测分析.结果表明,MBR内活性污泥微生物多样性低于普通活性污泥,微生物醌的类型也有所区别.MBR内活性污泥从未膨胀到膨胀严重期的活性污泥微生物多样性指数从10.90降到7.12;微生物种分布均匀度指数从0.84降到0.51,发生了逆行演替.对微生物醌组成的分析发现,微生物优势种群随环境变化而波动,UQ-9和MK-6在丝状菌膨胀的污泥中呈现明显优势.     

污泥处理条件对臭氧破解污泥能力的影响

利用臭氧强氧化性,使污泥细胞破解有机质溶出,实现活性污泥的全循环再生化处理,达到污泥“零排放”的目的.本研究改变处理条件(臭氧投加量、反应时间和空气进气量等),系统地检测反应前后污泥混合液的各项指标(总悬浮固体、挥发性悬浮固体、溶解性化学需氧量、氨氮、总磷、污泥沉降比),探讨臭氧氧化破解污泥反应的机理.由实验可知,在臭氧氧化破解污泥实验中,投加的臭氧量(相对于总悬浮固体)为0.27 g/g,反应时间为30 min,空气进气量为2.0 L/min时,破解的效果达到最佳,总悬浮固体的减少量达到2.8 g/L.气体流量越大破解效果越好,在空气进气量为2.0 L/min的条件下,臭氧氧化破解污泥实验效果最佳.随着臭氧投加量的增加,MLSS减少速率将由慢到快,然后趋于平缓,最佳投放量为0.25 g/g时,总悬浮固体减少量为1.42 g/L,SCOD的增加量为626 mg/L,氨氮和总磷的增加量分别为10.7、1.068 mg/L.     

好氧颗粒污泥膜生物反应器处理畜禽废水

采用好氧颗粒污泥膜生物反应器处理畜禽废水,分别对COD、NH4 -N、NO2--N、NO3--N的去除效果和对膜通量的影响进行了研究。结果表明:在水力停留时间(HRT)为8h,进水COD浓度为600mg/L,NH4 -N浓度为40mg/L的条件下,出水COD、NH4 -N的浓度分别为46.6和4.8mg/L。NO2--N和NO3--N的去除率也可达90%以上。并且好氧颗粒污泥的加入减缓了膜的污染。     

铜离子对SBR工艺活性污泥毒性作用分析

探讨了不同浓度铜离子对序列间歇式反应器(SBR)活性污泥系统中化学需氧量CODCr、总氮(TN)和总磷(TP)等去除的影响,并采用ToxTell生物传感器,以SBR活性污泥为指示微生物,分析了铜离子的毒性抑制作用.结果表明,铜离子质量浓度低于10mg.L-1时,不会对该SBR系统带来明显的冲击作用,其质量浓度超过20mg.L-1时则会导致系统出水水质明显下降、活性污泥量及污泥沉降比(SV)降低和污泥絮体的解体;ToxTell生物传感器的毒性分析结果与CODCr,TN和TP去除抑制率具有良好的一致性,初步证实该生物传感器能很好地用于铜离子冲击SBR活性污泥系统的预警监测.     

不同运行模式序批式膜生物反应器中污泥特性研究

比较了不同运行模式(AO、AOA及A 2O)对序批式膜生物反应器(SBMBR)污泥特性的影响.结果表明:运行模式对污泥粒径存在明显的影响,曝气时间较长的AO MBR及厌氧末引入缺氧段的A 2O MBR,有助于形成紧密而细小的颗粒.而粒径大且结构松散的污泥耗氧速率较高;充分的好氧时间则有利于耗氧速率的提高.好氧吸磷速率受运行方式影响,且与耗氧速率呈正相关性.适宜的厌氧阶段时长有助于提高污泥厌氧释磷能力;缺氧段及其位置的设置对反硝化除磷菌的选择与富集影响较大.本试验中A 2O MBR中反硝化聚磷菌(DPAOs)比例为40.6%,分别比AO及AOA MBR中提高了0.57和0.34倍.膜反应器中膜污染主要由膜表面滤饼层导致.曝气时间只是控制膜污染的因素之一,膜污染随污泥平均粒径的减小而加重,运行方式对膜污染也起着不可忽视的作用.     

臭氧在水处理中的应用

综述了臭氧的氧化分解机理和臭氧氧化法对水和废水中无机物、难降解有机物、色度的去除,以及臭氧在循环冷却水处理、剩余污泥消除和饮用水消毒杀菌方面的应用研究进展,分析了臭氧氧化法的优缺点,指出了催化氧化及臭氧与其他技术联用是今后的发展方向。     

城市污水H-A-O生物脱氮工艺研究

为同时去除城市污水中的有机物和氮,设计了水解-缺氧-好氧(H-A-O)生物脱氮处理工艺,建立了连续处理实验装置,并对该工艺进行了现场中试研究.结果表明:在总水力停留时间为7.5 h、硝化出水回流比为200%、无外加碳源和碱度、无污泥回流的条件下,有机物和总氮的去除率分别超过82%和65%;以水解取代传统的城市污水处理中初沉池,既可有效地改善污水的可生化性,又可增强污水处理系统运行的稳定性.     

电凝聚膜生物反应器膜过滤特性

以模拟印染废水为研究对象,考察了ECMBR和MBR系统中的膜污染和污泥混合液特性.结果表明:两系统膜过滤阻力均以沉积阻力为主,MBR和ECMBR中沉积阻力分占总阻力的99%和9334%,但ECMBR总阻力仅为普通MBR污泥总阻力的1/4,电凝聚可有效降低沉积层阻力.对比分析两系统中的混合液特性,ECMBR中污泥平均粒径大,Zeta电位绝对值小,胞外聚合物和溶解性微生物产物浓度低,污泥相对疏水性较高.电凝聚通过改变混合液特性,从而有效改善膜生物反应器过滤性能,增加膜通量,减少膜过滤阻力.     

长龄期简易填埋条件下污泥基本性质的变化

我国曾经有大量的污泥被随意弃置形成了许多简易污泥填埋场,简易填埋的污泥不受控制的堆放在自然环境中,其性质会随着时间发生变化。本文通过对江苏省某化工企业已经简易填存20年陈污泥的取样分析,发现经过多年的堆存,降解简易填埋陈污泥中的有机质含量仍高于50%;污泥中的pH值维持在8.5～9.0,适合产甲烷菌的生存条件;污泥中的含水率大多在90%以上,且水位线在污泥坑表层0～30cm变动,下部都呈厌氧饱和状态。该简易填埋场中老污泥中重金属Zn和Mn总量较高,但浸出量和渗沥液中的含量都很低,表明重金属不是污泥简易填埋场的主要污染物。渗沥液中COD、BOD₅、TN、NH₄-N、TP大多超标,表明简易污泥填埋场中的主要污染类型为有机污染。简易填埋污泥的渗透系数在10-8cm/s数量级,水分排出困难,不适合采用真空预压或堆载排水加固的方法对场地进行加固施工。     

紫茎泽兰炭对好氧颗粒污泥处理废水的影响

采用MUASB作为反应器,利用城市污水处理厂的活性污泥为接种污泥,加入不同级数紫茎泽兰炭通过间断曝气方式培养好氧颗粒污泥并用于处理高浓度有机废水。结果发现在20~40目、40~60目、60~80目、80~100目、100~190目紫茎泽兰炭中,添加40~60目紫茎泽兰炭在好氧颗粒污泥处理污水的表现上较为明显。在连续一个月的污水处理中,在好氧颗粒污泥中添加紫茎泽兰炭可调节污泥性能,并提高COD、NH3-N、TP的去除率。在COD8 000 mg/L时去除率达到90%以上,NH3-N去除率最高为99%以上,TP最高去除率达85%以上。     

脱氮污泥驯化方法初探及曝气量控制研究

采用进水浓度逐步上升方法驯化脱氮污泥,获得的活性污泥脱氮性能良好,氨氮去除率达到90%以上,TN去除率最高达到59.0%.实验表明:采用该方法驯化脱氮污泥,实现同步硝化反硝化是有效可行的.在进水氨氮浓度每一提高阶段,氨氮去除率总有下降阶段,但经过3~7周的适应性运行后,系统氨氮去除恢复稳定,达到95%以上.同时,在该实验范围内,COD的提高对氨氮去除也有明显影响,氨氮去除率也有先下降后升高,最终稳定的过程.不同曝气量控制实验发现,在中间曝气量下(本实验为0.7 L/min),能实现较好的脱氮效果,TN去除率达到41.2%.实验表明,存在一中间曝气量,低于或高于该中间值,TN去除率均会降低,当曝气量比较低时,不仅TN去除受影响,氨氮去除率也会降低.