生物过滤处理微污染原水的性能研究

以生物过滤作为微污染水处理的末级处理工艺,可使有机污染物和浊度的去除在同一滤层内实现,是一种经济、有效的生物处理方法。作者通过模型试验,深入探讨了生物过滤对微污染水中有机物、氨氮、浊度等的去除效果。试验结果表明：生物过滤能够有效地去除微污染水中的有机物、氨氮等物质,同时能够获得与常规过滤一样低的出水浊度。     

Performance of an industrial biofilter from a composting plant in the removal of ammonia and VOCs after material replacement

BACKGROUND: Biofiltration is a suitable odor reduction technique for the treatment of gaseous emissions from composting processes, but little is known about the start‐up of full‐scale biofilters after material replacement and their performance after several years of operation. RESULTS: Biofilter material (wood chips used previously as bulking agent in a composting process) can effectively remove ammonia and most of the volatile organic compounds (VOCs) content, achieving removal efficiencies greater than 70% for VOCs and near 90% for ammonia immediately after material replacement. These removal efficiencies were maintained for several months after material replacement. In the studied full‐scale biofilter no lag phase was observed in the removal of ammonia whereas in the case of VOCs different patterns were detected during biofilter start‐up. For the old biofilter material, after 4 years of operation, a statistically significant decrease of removal efficiency for ammonia in comparison with the new material was detected. No statistically significant differences were found in the case of VOCs. CONCLUSIONS: Data on the emissions of several pollutants from biofilters treating composting exhaust gases have been systematically obtained. The tested filtering media presented adequate properties for biofiltration of gases emitted during the composting process. Copyright © 2009 Society of Chemical Industry     

生物过滤在微污染水处理中的应用

以生物过滤作为微污染水处理的末级处理工艺 ,使有机污染物和浊度的去除在同一滤层内实现 ,是一种经济、有效的生物处理方法。本文分析讨论了生物过滤技术在实际应用中的具体形式和影响因素并展望了今后主要的研究方向     

Effectiveness of AOC removal by advanced water treatment systems: a case study

Recently, the appearance of assimilable organic carbon (AOC) in the water treatment system and effluent of the treatment plant has brought more attention to the environmental engineers. In this study, AOC removal efficiency at the Cheng-Ching Lake water treatment plant (CCLWTP) was evaluated. The main objectives of this study were to: (1) evaluate the treatability of AOC by the advanced treatment system at the CCLWTP, (2) assess the relativity of AOC and the variations of other water quality indicators, (3) evaluate the effects of sodium thiosulfate on AOC analysis, and (4) evaluate the efficiency of biofiltration process using granular activated carbon (GAC) and anthracite as the fillers. Results show that the averaged influent and final effluent AOC concentrations at the CCLWTP were approximately 124 and 30 μg acetate-C/L, respectively. Thus, the treatment plant had an AOC removal efficiency of about 76%, and the AOC concentrations in the final effluent met the criteria established by the CCLWTP (50 μg acetate-C/L). Results indicate that the biofiltration process might contribute to the removal of the trace AOC in the GAC filtration process. Moreover, the removal of AOC had a correlation with the decrease in concentrations of other drinking water indicators. Results from a column test show that GAC was a more appropriate material than anthracite for the AOC removal. Results from this study provide us insight into the mechanisms of AOC removal by advanced water treatment processes. These findings would be helpful in designing a modified water treatment system for AOC removal and water quality improvement.     

生物过滤去除饮用水中微量有机物的研究与发展

简要回顾了最近20多年来国内外对饮用水生物过滤的研究历史，运用Lawrence-McCarty公式和微生物增殖基本方程式，推导了最小基质浓度Smin的计算公式，阐明了第二级利用机理是生物过滤去除饮用水中微量的合成有机物的主要机理，自然有机物是降解微量合成有机物的微生物的主要碳源和能源。探讨了过滤介质、空床接触时间、反冲洗方式、水温、水源水质和预氧化等因素对生物过滤效果的影响，展望了饮用水生物过滤的发展方向及在我国微污染饮用水处理方面的应用前景。     

Treatment of perchlorate in drinking water: A critical review

Because of its extremely low concentrations and strong resistance to most treatment technologies, perchlorate has become one of the biggest challenges currently being faced by the drinking water industry. Although significant research has been performed to evaluate different treatment technologies for perchlorate removal from drinking water, there has not been a holistic review performed recently. A complete and critical review on the intriguing contaminant ‘perchlorate’ is presented. The sources of perchlorate along with the degree of contamination are discussed. The policy aspects including the regulation and toxicity in addition to the most recent developments in perchlorate analysis are also considered. The applicable treatment technologies including their feasibility are discussed in detail. Although some technologies such as microbial reduction and ion-exchange have become more established than the others, there is still not a single technology that can be directly applied to a drinking water treatment system for compete removal of perchlorate. Although significant research is still being conducted to come up with a novel technology for perchlorate remediation, it is highly likely that it would not be a single novice or conventional technology but a combination of these technologies that would have to be employed to overcome this challenge.     

生物慢滤对污染物的去除效果研究

生物慢滤作为预处理可以充分发挥微生物的生物降解作用,初步去除原水中的有机污染物及氮、磷等无机污染物。研究了生物慢滤作为预处理措施处理微污染原水的效果。结果表明,生物慢滤对于去除水中浊度、CODMn、NH4＋-N、TN、TP有很好的处理效果,平均去除率分别达到92.3%、34.5%、90.2%、45.2%、30.6%。     

Effect of pre‐treatments based on UV photocatalysis and photo‐oxidation on toluene biofiltration performance

BACKGROUND: The integration of UV photocatalysis and biofiltration seems to be a promising combination of technologies for the removal of hydrophobic and poorly biodegradable air pollutants. The influence of pre‐treatments based on UV_{254 nm} photocatalysis and photo‐oxidation on the biofiltration of toluene as a target compound was evaluated in a controlled long‐term experimental study using different system configurations: a standalone biofilter, a combined UV photocatalytic reactor‐biofilter, and a combined UV photo‐oxidation reactor (without catalyst)‐biofilter. RESULTS: Under the operational conditions used (residence time of 2.7 s and toluene concentrations 600–1200 mg C m^?3), relatively low removal efficiencies (6–3%) were reached in the photocatalytic reactor and no degradation of toluene was found when the photo‐oxidation reactor was operated without catalyst. A noticeable improvement in the performance of the biofilter combined with a photocatalytic reactor was observed, and the elimination capacity of the biological process increased by more than 12 g C h^?1 m^?3 at the inlet loads studied of 50–100 g C h^?1 m^?3. No positive effect on toluene removal was observed for the combination of UV photoreactor and biofilter. CONCLUSIONS: Biofilter pre‐treatment based on UV_{254 nm} photocatalysis showed promising results for the removal of hydrophobic and recalcitrant air pollutants, providing synergistic improvement in the removal of toluene. Copyright © 2011 Society of Chemical Industry     

生物过滤处理微污染饮用水源的试验研究

通过试验探讨了生物过滤对微污染饮用水源的处理效果及其影响因素。试验结果表明，生物过滤可有效去除湘江微污染饮用水源中的有机物、NH3-N、Fe、Mn和浊度。滤料介质、空床接触时间和加氯水反冲洗等因素对生物过滤均具有明显的影响。     

活性碳-石英砂双层滤池去除氨氮和亚硝酸盐氮的特性

通过一个水文年的小试试验,研究了活性炭-石英砂双层滤池(简称炭砂滤池)作为快滤池时对水中氨氮和亚硝酸盐氮的去除特性。结果表明:炭砂滤池能稳定且有效去除水中的氨氮和亚硝酸盐氮,试验期间滤池出水氨氮浓度一般低于0.1 mg/L,出水NO2--N浓度一般低于检出限,运行效果优于水厂传统砂滤池。在试验进水水质条件下,氨氮和亚硝酸盐氮主要在滤池上部0.4 m活性炭层被去除。高滤速和水力波动会使炭砂滤池去除氨氮和亚硝酸盐氮的效果变差。水温和反冲洗对滤池去除氨氮和亚硝酸盐氮的效果影响不大,高温条件以及反冲洗后滤池对氨氮和亚硝酸盐氮的沿程去除速率略有提高。     

国内饮用水生物稳定性的调查研究

以国内几个大中城市的自来水厂为调查对象,测定了不同水厂各工艺出水中AOC浓度,分析了不同水处理工艺对AOC的去除特性,并对国内饮用水的生物稳定性进行了分析。调查结果表明：1)水源的污染程度对饮用水中AOC浓度有重要影响。原水AOC随着污染程度的增加而增加。2)常规处理工艺对AOC具有一定的去除效果,且去除率随水温的升高而增加。3)活性炭处理对AOC去除率较高,活性炭对AOC的去除包括物理吸附和活性炭上附着的微生物降解两部分。4)水厂工艺出水加氯消毒后,AOC浓度均有较大幅度的增加。因此应该重视开展加氯消毒对管网水质影响的研究,寻求采用科学的消毒方法以控制细菌的生长。5)目前国内大多数饮用水属于生物不稳定饮用水。应在加强水源保护的同时,增加深度处理工艺如活性炭或膜处理来提高饮用水水质。     

Treatment of methanol vapours in biofilters packed with inert materials

BACKGROUND: Methanol is a major pollutant emitted in Canada. Methanol is toxic to humans and it is associated with environmental problems such as smog generation. Biofiltration is a treatment method of considerable interest for controlling methanol emissions, because of its characteristics: no production of hazardous wastes, low energy consumption and low operating costs. The present study analyzed the effects of porous and non‐porous packing materials, the nitrogen concentration in nutrient solution and the methanol inlet load on biofilter performance and biofilm characteristics. RESULTS: The biofilter packed with porous material presented a removal efficiency up to 95%, which was higher than the 35% removal efficiency with the non‐porous material. Inlet load (IL) influenced the biomass and carbon dioxide production rates. The critical inlet load (IL_crit) occurred at 80 g m^?3 h^?1. The cellular densities of methylotrophs and non‐methylotrophs were affected by all operating variables examined. CONCLUSION: Biofiltration can be applied for controlling methanol emissions with high removal efficiency. The cellular density of methylotrophs is correlated with the performance of the biofilter. Copyright © 2008 Society of Chemical Industry     

磁性离子交换树脂强化水源中有机物去除性能研究

在调查某水厂水源水质及传统工艺处理效能的基础上,对比探讨了粉末活性炭和磁性离子交换树脂分别以预吸附、预吸附-混凝、混凝沉淀-吸附等不同工艺对水源水中溶解性有机物的去除效能,确定了最佳工艺。该水源存在季节性有机物污染,亲水性有机质占比80%。水厂传统工艺对有机物的去除能力约20%~30%。与其他工艺相比,树脂预吸附-混凝对有机物的去除功效最好,DOC和UV254的去除率分别达到41.48%和80.0%,与单独强化混凝相比,该工艺可将DOC和UV254的去除效率分别提高17.7和35.49个百分点,且可减少86.67%的混凝剂投加量。Langmuir等温线模型和拟二级动力学方程可定量描述树脂吸附有机物平衡和动力学。磁性离子交换树脂预吸附可作为该水厂强化去除水源中溶解性有机物的可靠技术。     

Performance evaluation and mathematical modelling of granular activated carbon biofiltration in wastewater treatment

Biological filtration is an effective technique for removing organic matter from wastewater. The performance of a biofilter can be influenced by a range of operational conditions. In this study the performance of biofilters was investigated for the influence of filter media depth, influent concentrations, filtrations rates and backwashing. The results show that performance of GAC filters decreased with shallower filter bed depths. In addition, the GAC performed better at lower influent concentration and lower filtration rates. The daily backwash adopted to avoid the physical clogging of the biofilter did not have any significant effect on the organic removal efficiency of the filter. The concentration, activity and characteristics of the biomass are quantified and described. A mathematical model was developed to simulate the organic removal of the GAC biofiltration system. The performance of the GAC filter under different influent organic concentration levels, filtration rates and filter bed depths was adequately simulated by the mathematical model developed for this study.     

Designing Integrated Ozone-Biofiltration Treatment Systems

The ozone-biofiltration (OBF) process can be an effective treatment process for achieving multiple water quality goals ranging from primary disinfection to oxidation of taste and odor compounds to removing biodegradable organic matter. However, ozone and biofiltration processes are typically designed as separate unit processes rather than as an integrated treatment process, so opportunities are often missed for incorporating synergistic design and operational benefits. The purpose of this article is to present design issues and monitoring and control strategies for designing an integrated OBF treatment system based on a review of industry literature and the author’s design experience.     

物理法水处理技术

近年来我国的水环境和水生态得到了明显的改善,但仍然存在很多的问题,水污染治理形势依然相当严峻。物理分离由于可不加或少加化学、生物药剂,造成二次污染的风险小,被认为是清洁的水处理技术。突破常规以生化法为核心的矿化模式,构建以物理分离法为核心的资源化模式,可减少化学和生物药剂消耗、减排二次污染物,为我国水环境安全提供一条新路线。以市政污水、饮用水、工业水和海上油气开采生产水为例,介绍了物理法水处理技术的最新成果,从而为物理法变革性水处理技术提供新思路。     

Supercritical water oxidation treatment of humic acid as a model organic compound of landfill leachate

Landfill leachate is a complex and variable effluent, rich in organic and inorganic matters resistant to decomposition, and is an extreme pollutant. Humic acids (HA) are some of the most refractive substances in the leachates, which is the reason why they have been used as an organic model. The degradation of an HA solution through supercritical water oxidation (ScWO) was evaluated under a constant pressure of 22.5 MPa, temperatures from 400°C to 600°C, and reaction times from 15 to 60 seconds. The results showed that the most influential factor was temperature and it guided the operational conditions of the ScWO for the landfill leachate (22.5 MPa, 600°C, and 60 seconds). The landfill leachate treatment promoted high removal rates of true colour (87%), total dissolved solids (94%), nitrate (70%), and total phosphorus (96%). In addition, it removed 57% of the COD, which was similar to the HA removal rate (61%) under the same operational conditions. This indicates that HA are an adequate organic model for landfill leachates. The results suggest that ScWO is a clean and promising treatment technology that can be applied to landfills and can have even better results if used in combination with oxidizers and catalysts, or with the use of higher temperatures.     

光催化技术在水处理中的应用研究进展

光催化技术在水处理领域的应用,既可以提高水质安全,也可以缓解全球能源和水资源短缺问题,是一项具有广泛应用前景的技术。本文首先介绍了光催化技术的基本原理及常用光催化剂的特点,综述了光催化剂技术在饮用水和废水处理应用方面的研究进展及发展方向,重点介绍了光催化技术在饮用水中的除嗅、消毒,在染料废水、含油废水、制药废水、催化还原重金属离子、养殖废水、焦化废水方面的应用,为类似污染水质的处理提供了的参考依据,最后对光催化技术及光催化剂的发展进行了展望。     

Nanofiltration for drinking water treatment: a review

In recent decades, nanofiltration (NF) is considered as a promising separation technique to produce drinking water from different types of water source. In this paper, we comprehensively reviewed the progress of NF-based drinking water treatment, through summarizing the development of materials/fabrication and applications of NF membranes in various scenarios including surface water treatment, groundwater treatment, water reuse, brackish water treatment, and point of use applications. We not only summarized the removal of target major pollutants (e.g., hardness, pathogen, and natural organic matter), but also paid attention to the removal of micropollutants of major concern (e.g., disinfection byproducts, per- and polyfluoroalkyl substances, and arsenic). We highlighted that, for different applications, fit-for-purpose design is needed to improve the separation capability for target compounds of NF membranes in addition to their removal of salts. Outlook and perspectives on membrane fouling control, chlorine resistance, integrity, and selectivity are also discussed to provide potential insights for future development of high-efficiency NF membranes for stable and reliable drinking water treatment.     

用生物活性炭纤维新技术去除水中有机污染物

研制了生物活性炭纤维，用于去除水中有机污染物。采用循环流动法把微生物固定在活性炭纤维上，并用扫描电镜观察微生物在炭表面的生长情况。测试了生物活性炭纤维去除微污染源水中有机物的性能，并通过GC—MS图谱分析了处理前后水中有机物的变化。经处理后，水中的CODMn降到了2．5mg／L(饮用水的标准)以下，UV254的平均去除率高达94％，处理容量达到2880mL／g。另外，在相同的实验条件下，将生物活性炭与活性炭纤维的吸附性能作了对比，结果表明以ACF作为载体的生物活性炭纤维(BACF)技术在处理容量和处理效果上均显著优于其它两种处理方法，显示了此项新技术在水的深度处理领域的巨大应用潜力。