影响臭氧化污泥减量工艺的因子

采用臭氧作为剩余污泥的细胞裂解剂,并与淹没式生物膜工艺相结合进行污泥减量的实验研究,臭氧化后的污泥上清液回流入曝气池与污水合并处理。结果表明:在每kgMLSS臭氧投量为0.05 kg,臭氧化污泥体积流量为进水量的5%条件下,淹没式生物膜系统对SCOD和NH3-N的平均去除率分别为87.06%和84.80%,出水水质同对比实验相当;同时获得了去除1 g SCOD得到0.054 gMLSS的剩余污泥产率,与对比实验相比降低了78.4%。     

臭氧化污泥减量技术的研究进展

阐述了臭氧化污泥减量技术的机理、臭氧化污泥的性状变化、污泥减量效果的影响因素、污泥臭氧化对出水水质的影响等。表明了臭氧化污泥减量技术在不影响出水水质的情况下,能有效地减少剩余污泥量,还能提高系统的反硝化能力,具有广阔的应用前景。     

城市污水处理厂的污泥臭氧化减量技术

针对城市污水处理厂产生大量的污泥,综述了臭氧化污泥减量技术的国外研究成果,介绍并讨论了臭氧化污泥减量的原理、污泥减量效率与臭氧剂量的关系、臭氧化污泥回流对污水处理运行效果及对污泥沉降脱水性能的影响,对臭氧化污泥减量技术进行经济评估,表明臭氧化污泥减量技术具有广泛的应用价值。     

膜生物反应器臭氧化同步污泥减量新工艺的研究

提出将臭氧直接充入到MBR中的同步臭氧化污泥减量新工艺,考察了同步臭氧化对MBR污泥产率及出水水质的影响.结果表明臭氧投加量为0.025 gO3/gVSS时,同步臭氧化对MBR具有显著的污泥减量效果,污泥产率系数Yobs为0.0096 g(MLSS)/g(COD),而对比工艺污泥产率系数Yobs为0.1147 g(MLSS)/g(COD),同时对COD和NH4+-N的去除率分别维持在91%和95.7%以上.     

臭氧耦合A/A/O污泥减量及污水处理效能研究

将剩余污泥臭氧化与A/A/O工艺系统耦合,在3种回流方式下,研究了臭氧耦合A/A/O系统的污泥减量效果和污水处理效能。结果表明,臭氧耦合A/A/O系统污泥减量效果明显,20 d内,3种不同回流方式下累积排泥量较传统A/A/O工艺系统分别下降了51.3%、49.8%、47.6%。臭氧化污泥回流对系统出水COD无明显冲击,同时提高了污泥沉降性和系统的脱氮能力。臭氧化污泥回流至厌氧区时系统TP去除率下降,而回流至缺氧区时则可以小幅提升TP去除率。综合考虑污泥减量效果和污水处理效能,认为将臭氧化污泥等比例回流至厌氧区和缺氧区为最佳回流方式。     

臭氧化污泥减量技术对出水水质的影响

为了探讨剩余污泥减量问题,采用臭氧氧化法处理曝气池回流污泥,考察臭氧氧化污泥减量技术对出水COD、NH3-N和TP的影响。实验结果表明：剩余污泥的比脱氢酶活性随通臭氧时间的延长而减少：在被臭氧氧化的泥水混合液中,SCOD的值是随时间的延长而增大;臭氧处理后的剩余污泥排入曝气池中,出水的COD、TP去除率无明显变化,出水NH3-N去除率有所增加。     

关于臭氧氧化污泥减量技术的研究

活性污泥法处理污水产生的大量剩余污泥已成为大多数污水处理厂亟待解决的问题,而污泥减量就是从源头上减少污泥的产生。臭氧氧化技术是一种有潜力的清洁无二次污染的污泥减量技术。文中阐述了臭氧在污泥减量技术中的应用背景及基本原理,从不同角度分析了臭氧氧化技术的应用现状,指出了最新的研究热点以及当前存在的问题和未来可能的发展方向。     

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。     

低剂量臭氧氧化与延时曝气活性污泥法相结合的污泥前置减量技术在集中式工业污水处理厂的应用实践研究

介绍污泥减量技术的应用背景和已有的污水处理中的污泥减量技术及各自的优势和不足。通过臭氧催化氧化与延时曝气相结合的污泥减量技术在集中式工业污水处理厂的应用实践,提出了污泥表观产率新的计算公式Yobs=a VSS/g COD去除+b NVSS/g TSS进水。发现了污泥表观产率的由对照组的Yobs VSS=0.188g VSS/g COD去除,Yobs NVSS=0.442g VSS/g TSS进水降低到实验组的Yobs VSS=0.104g VSS/g COD去除,Yobs NVSS=0.177g VSS/g TSS进水。,VSS表观产率下降了44.7%;NVSS表观产率下降了60%。文中分析阐述了污泥表观产率与系统削减COD负荷和进水TSS的关系,臭氧氧化部分回流污泥与延时曝气相结合的污泥减量技术的基本原理,比较了它与传统臭氧氧化污泥减量技术不同之处,及在工业污水污泥减量上的意义,并指出臭氧氧化污泥减量当前在生产应用上仍存在的问题。     

ClO2耦合超声波破解污泥回流SBR系统的隐性生长污泥减量研究

为了考察系统污泥减量效果及污泥回流对系统污水处理效果的影响,探讨实现污泥减量的机制,将70％剩余污泥经ClO2耦舍超声波处理后回流至SBR中试系统,运行30d,测定系统累计排泥量、系统出水水质、污泥活性、污泥沉降性能等指标。结果表明,经ClO2耦合超声波处理后的剩余污泥回流至系统后,产泥量减少了54．86％。污泥回流对SBR系统的SS、CODCr、NH3-N和TN去除效果无影响,对TP的去除率有所降低。当量表观污泥产率从对照组的0．410kg[SS]／kg[CODCr]降低到了0．186kg[SS]／kg[CODCr],当量衰减系数由对照组的0．0360d—I提高到0．0602d-1。系统能保证出水水质稳定。污泥减量效果显著。     

臭氧氧化与序批式好氧活性污泥法组合工艺的污泥减量化效果

该文研究了臭氧技术应用于剩余污泥处理过程中臭氧利用率及污泥的可生化性随时间的变化,组建了臭氧氧化与序批式好氧活性污泥法结合的联合工艺。将臭氧单元处理过的污泥全部回流至曝气池与污水进行合并处理,考察了不同臭氧投加量下联合工艺中剩余污泥的产量和污水处理效果。结果表明,当处理污泥浓度为4 000 mg/L,污泥体积为3 L,臭氧进气浓度为6.5 mg/L,气量为6 L/min时,前20 min的臭氧利用率几乎为100%,随后利用率逐渐降低;污泥的可生化性先降低,而后逐渐升高,在30 min时达到最大,其后又开始下降;当臭氧投加量为0.078 kg O3/kg MLSS时,联合工艺的污泥增长率几乎为0,同时出水水质相对对照组没有明显变化。     

Effect of Ozonation on Biodegradability Characteristics of Surplus Activated Sludge

The study investigates the effect of sludge ozonation on solid matter species, disintegration properties, sludge components, and solubilization characteristics under different operating conditions. Ozonation of surplus activated sludge samples taken from the secondary settling tank of a domestic wastewater treatment plant indicates that soluble nitrogen, phosphorus and COD concentrations proliferate as a consequence of extending the ozone feeding time. A steady increase both in soluble nitrogen concentration and ratio of organic phosphorus to soluble phosphorus is observed through ozonation where specific ozone doses range between 4 and 11 mg O₃/g SS. Combined treatment of chemical oxidation and aerobic biodegradation to surplus activated sludge is also applied to improve the biodegradability of organic matter by partial chemical oxidative pretreatment with as little specific ozone consumption as possible. The partial oxidation by integrated ozonation is operated as a pre-oxidation step for the subsequent biological degradation, due to the fact that the competition with biological degradation in removing biodegradable organic compounds is avoided and most probably a more biodegradable sludge composition is obtained by means of ozonation. Combined treatment of chemical oxidation and aerobic biodegradation conducted to scrutinize the synergic effect of the coupled treatment system reveals that TS and COD removal efficiencies of ozonated sludge samples cannot be improved beyond the third aerobic biodegradation step.     

臭氧尾气回用对曝气池污泥影响研究

将活性污泥分别在14.68、30.72、43.84 mg/L 3种臭氧浓度下进行氧化,同时以纯氧曝气作为平行实验,考察臭氧尾气对活性污泥的影响。结果表明,污泥经纯氧曝气后,在反应时间内并无明显变化,但在臭氧氧化过程中,污泥ATP下降,同时上清液中COD、TP、TN上升,且臭氧浓度越高,变化速率越大,其原因为污泥发生了溶胞现象;臭氧氧化后,污泥MLSS、MLVSS减少,污泥呼吸速率下降,但沉降性得到改善,同样随着臭氧浓度的升高,变化更为显著。经14.68、30.72 mg/L臭氧氧化后的污泥,其硝化能力、生化能力与反应前并无明显差距,而经43.84 mg/L臭氧氧化后污泥的硝化能力、生化能力明显弱于反应前。     

Ozonation of Continuous-Flow Activated Sludge for Reduction of Waste Solids

The ultimate disposal of wastewater sludge has been, and continues to be, one of the most expensive problems faced by wastewater utilities in the United States. The objective of this research was to apply cell lysis and cryptic growth principles to activated sludge to study the applicability of ozonation to reduce the mass of secondary sludge. The study produced data and details for application of ozone to reduce secondary sludge production. The application of ozone reduced the mass of waste sludge by 30 to 50% depending on the ozonation rate and period.     

Effect of Ozone on Viability of Activated Sludge Detected by Oxygen Uptake Rate (OUR) and Adenosine-5′-triphosphate (ATP) Measurement

The current study focused on treatment of phenolic wastewater using an integrated process – dosing of ozone directly to activated sludge. The main goal was to analyze the effect of ozonation on viability of activated sludge in different systems – activated sludge in distilled water and activated sludge in wastewater. Two viability detection methods, oxygen uptake (OUR) rate and adenosine-5'-triphosphate measurement (ATP), were compared. The linear correlation between ATP and OUR measurements in studied range was found to be good (r² = 0.90). In case of ozonation of activated sludge in wastewater, ozone doses up to 42 mgO₃·gMLVSS^?1 did not influence the viability of sludge. In addition, contrary to ozonation of sludge in distilled water, soluble COD was reduced by 15.6% (at ozone dose of 42 mgO₃·gMLVSS^?1).     

Activated sludge process coupled with intermittent ozonation for sludge yield reduction and effluent water quality control

BACKGROUND: Ozone is applied in wastewater treatment for effluent water quality improvement (post‐ozonation) as well as for excess sludge reduction (in the recirculation line). There is some evidence that ozone dosed directly to aerobic biooxidation (ABO) process enhances degradation of recalcitrant compounds into intermediates, following their biodegradation in the same reactor. However, no information regarding the influence of ozone on sludge yield in this system was found. Therefore, the current work aimed to evaluate the effect of ozone on the sludge yield when ozone is dosed directly to the ABO process. In addition, batch and continuous treatment schemes for phenolic wastewater treatment are compared. RESULTS: The results revealed that an optimal ozone dose of ～30 mgO₃ L^?1 day^?1 reduced the sludge yield by ～50%, while effluent water quality in terms of total chemical oxygen demand (TCOD), compared with a conventional ABO process, was improved by 35.5 ± 3.6%. Slight improvement in soluble COD removal at the same ozone dose was also detected. The toxicity of effluent water was reduced as the ozone dose was increased. CONCLUSIONS: In an integrated ozonation‐ABO process it is possible to simultaneously reduce sludge yield and to improve effluent water quality, as COD and toxicity are reduced. Copyright © 2011 Society of Chemical Industry     

Improved Sludge Dewaterability for Sequential Ozonation – Aerobic Treatment

Chemical treatment processes such as ozonation have mostly been considered as an efficient way for bio-solids minimization. The improvement of sludge dewatering was more a welcoming side-effect in these sequential processes. However, sometimes the loaded ozone dose to the sludge has a negative effect on dewaterability. This work address the most important issue found — the effect of ozone on sludge dewaterability in a single ozonation processes as well as in a sequential ozonation biological processes. It was found that the maximum sludge dewaterability was achieved with an ozone dose of 0.05 gO₃/gTSS. This value was found to be less than the required ozone dosage that leads to sludge disintegration. However, it was observed that the sequential ozone and aerobic treatment allows further strong improvement of dewatering efficiencies.     

Influence parameters in the ozonation of phenol wastewater treatment using bubble column reactor under continuous circulation

The ozonation of phenol wastewater treatment system has been investigated with effective mass transfer between gas and liquid phase in a bubble column reactor. The designed bubble column reactor was investigated for increasing the rate of mass transfer of ozone, the rate of oxidation of phenol in the solution, the solubility and decomposition rate of ozone in the distilled water were also studied at different flow rates. The decomposition rate constants were calculated based on pseudo first order kinetics. The oxidation of phenol was investigated in order to provide the overall reaction rate constant for the reaction between ozone and phenol at 25 °C. The influence of the operating parameters like initial phenol concentration, ozone flow rate and pH for the destruction of phenol by ozonation were studied. The pseudo first order rate constant was depending on the initial concentration of phenol solution. A comparison of TOC removal percentage between bubble column reactor and bubble diffuser using ozonation were reported.     

Oxidation of Organic Pollutants of Water to Mineralization by Catalytic Ozonation

The oxidation of various organic compounds in aqueous solution was studied using catalytic ozonation (TOCCATA process) and conventional ozonation. The aim of the work is to assess catalytic ozonation efficiency for the mineralization of various organic compounds in order to envisage its application on real effluents. The selected organic compounds (about 30) are commonly found in industrial wastewaters. Comparative experiments were performed in batch mode at laboratory scale. Investigations were focused on ozone consumption rate, variations of total organic carbon, oxidation by-products and oxidation rate. Catalytic and conventional ozonation treatments were compared considering kinetic data, mineralization extent, and effect of organic functionalities. Catalytic ozonation system according to the TOCCATA process was able to convert organic compounds which were totally inert to ozone treatment and permitted considerably enhanced reaction rates when compounds were reactive to ozonation.     

Ozone as a Pretreatment Method for Antibiotic Contaminated Wastewater and Sludge

ABSTRACT

The capability of ozone to reduce the hazardous impact of environmentally persistent antibiotic tiamulin in term of toxicity reduction and enhancement of biodegradability was investigated. Different ozone doses were applied but ozonation was not effective enough to increase the biodegradability of tiamulin in the aqueous phase. The opposite effect was observed in anaerobic digestion experiments, where ozonation as a pretreatment step of antibiotic-contaminated sludge detoxify tiamulin and improves biogas production for 75%. As confirmed by ¹H NMR and HPLC-HRMS analyses, the tiamulin molecule completely reacts with ozone at low ozone/COD molar ratio of 0.03, primarily attacking the vinyl double bond with further oxidation of sulfur and nitrogen atom, and gradual decomposition of tiamulin skeleton.