苯酚废水的高级氧化处理技术

以催生·OH自由基为主要氧化剂来氧化处理废水中难降解有机物的高级氧化技术正成为国内外研究的热点课题.分析了多种高级氧化技术对苯酚废水处理的共同作用机理,阐述了催化湿式氧化法、光催化氧化法、电催化技术、超声声化学氧化、超临界水氧化等在含酚废水高级氧化处理中的研究进展及发展趋势.     

Catalytic oxidation with Al-Ce-Fe-PILC as a post-treatment system for coffee wet processing wastewater

The effluent from the anaerobic biological treatment of coffee wet processing wastewater (CWPW) contains a non-biodegradable compound that must be treated before it is discharged into a water source. In this paper, the wet hydrogen peroxide catalytic oxidation (WHPCO) process using Al-Ce-Fe-PILC catalysts was researched as a post-treatment system for CWPW and tested in a semi-batch reactor at atmospheric pressure and 25 °C. The Al-Ce-Fe-PILC achieved a high conversion rate of total phenolic compounds (70%) and mineralization to CO(2) (50%) after 5 h reaction time. The chemical oxygen demand (COD) of coffee processing wastewater after wet hydrogen peroxide catalytic oxidation was reduced in 66%. The combination of the two treatment methods, biological (developed by Cenicafé) and catalytic oxidation with Al-Ce-Fe-PILC, achieved a 97% reduction of COD in CWPW. Therefore, the WHPCO using Al-Ce-Fe-PILC catalysts is a viable alternative for the post-treatment of coffee processing wastewater.     

臭氧高级氧化技术深度处理印染废水试验研究

研究单独臭氧氧化、O3/H2O2、O3/非均相催化臭氧化技术对去除难降解染料废水CODcr、色度、UV254和提高可生化性的效果。实验结果表明:印染废水最适宜的深度处理方法是O3/MnOx-GAC。当O3投加量为81mg/L时,O3/MnOx-GAC对CODcr、色度和UV254的去除率分别为36.23%、70%和60.67%,B/C由原来的0.1上升到0.26,可采用后续生化处理进一步去除有机物。     

Integration of chemical and biological oxidation in a SBBR for tannery wastewater treatment.

This paper reports the results of an investigation aimed at evaluating the laboratory-scale performance of an innovative process for treating tannery wastewater. In this process, biological degradation, carried out in a sequencing batch biofilm reactor (SBBR), is combined with chemical oxidation by ozone. Tannery wastewater treatment was carried out, at laboratory scale, on a real primary effluent coming from a centralised plant treating wastewater produced by a large tannery district in Northern Italy. SBBR performance both without and with ozonation, was assessed with very satisfactory results. In particular, in the latter instance the recorded COD, TKN and TSS average removals, (96%), (92%) and (98%) respectively, allowed the maximum allowable concentration values fixed by the Italian regulation in force to be achieved without any additional polishing step. During the investigation biofilm properties (biofilm concentration and biofilm density) and flow dynamics aspects (head loss, shear stress, bed porosity) were also studied. A major feature of the process is that, with or without ozonation, it was characterised by very low specific sludge production (0.05 kgVSS/kgCODremoved) and high biofilm density (i.e. 87-122 gVSS/Lsludge) both contributing to a rather high biofilm concentration (i.e. 31-44 gTSS/Lfilter).     

火力发电厂含煤废水处理系统设计

依据对规范的理解和对电厂运行的调研,建议在含煤废水处理系统设计过程中应注意:转运站含煤废水和煤仓间含煤废水向煤水沉淀池宜采用压力输送,同时考虑采用从源头杜绝大颗粒煤进入含煤废水集水坑、含煤废水管网单元制和对含煤废水管网用输煤栈桥冲冼水冲冼三种措施.煤场雨水沉淀池的容积应与当地降雨量资料相适应.煤水处理装置能力宜与煤场雨水沉淀池的容量相匹配,按1～1.5 d处理完煤场雨水沉淀池的全部水量来确定.     

Anaerobic pond treatment of wastewater containing sulphate.

Anaerobic ponds are usually used for treatment of industrial and agricultural wastes which contain high organic matter and sulphate. Competition for substrate between sulphate reducing bacteria and methane producing archaea, and the inhibitory effects of sulphide produced from microbial sulphate reduction reported in the literature varied considerably. In this research, a laboratory scale column-in-series anaerobic pond reactor, consisting of five cylindrical columns of acrylic tubes, was operated to evaluate the effect of COD and sulphate ratio on pond performance treating wastewater containing high organic matter and sulphate from a tapioca starch industry. The result depicted that no adverse effect of COD:SO4 ratios between 5 and 20 on overall COD removal performance of anaerobic pond operated with organic loading rate (OLR) of 150 to 600 g COD/m3d. Sulphate reducing bacteria could out-compete methane producing archaea for the same substrate at COD:SO4 ratio equal to or lower than 5 and OLR greater than 300 g COD/m3d. Sulphide inhibition was not observed on overall performance of pond up to an influent sulphate concentration of 650 mg/L.     

Aqua-Biomant: integrated biological and electrochemical oxidation for industrial wastewater treatment.

An innovative technology for industrial wastewater treatment has been developed. The main focus of the new system is a transformation of persistent organic compounds (biorecalcitrant COD) into a biodegradable fraction, followed by high efficient biological elimination using specialised bacteria's. To fulfill these targets the Aqua-Biomant process integrates two treatment steps: an aerated biological upflow filter and a electrochemical oxidation technique using boron doped-diamond electrodes. The advantages of the process are high efficient COD removal with reduced energy consumption combined with low total residence time.     

Phenol wastewater remediation: advanced oxidation processes coupled to a biological treatment.

Nowadays, there are increasingly stringent regulations requiring more and more treatment of industrial effluents to generate product waters which could be easily reused or disposed of to the environment without any harmful effects. Therefore, different advanced oxidation processes were investigated as suitable precursors for the biological treatment of industrial effluents containing phenol. Wet air oxidation and Fenton process were tested batch wise, while catalytic wet air oxidation and H2O2-promoted catalytic wet air oxidation processes were studied in a trickle bed reactor, the last two using over activated carbon as catalyst. Effluent characterisation was made by means of substrate conversion (using high liquid performance chromatography), chemical oxygen demand and total organic carbon. Biodegradation parameters (i.e. maximum oxygen uptake rate and oxygen consumption) were obtained from respirometric tests using activated sludge from an urban biological wastewater treatment plant (WWTP). The main goal was to find the proper conditions in terms of biodegradability enhancement, so that these phenolic effluents could be successfully treated in an urban biological WWTP. Results show promising research ways for the development of efficient coupled processes for the treatment of wastewater containing toxic or biologically non-degradable compounds.     

船型一体化氧化沟处理乳制品废水工程实例分析

介绍了采用船型一体化氧化沟处理乳制品厂废水的工程实例,指出了其主要工艺特色,并对运行过程中出现的问题进行了讨论。工程实践表明,该氧化沟具有较高的COD,BOD,SS及NH3-N去除率,且基本没有剩余污泥产生,氧化沟与沉淀池合建占地少,流程短,但对P的去除效果较差。     

Anoxic sulfide oxidation in wastewater of sewer networks.

Investigations on anoxic sulfide oxidation in wastewater under sewer conditions are presented. Batch tests were designed and conducted to study both chemical and biological sulfide oxidation by nitrate in the water phase. Oxidation at pH 7.0 and 8.5 was performed in parallel and wastewater with anaerobic storage period of 0, 3, 4, 6 days was used. Initial sulfide concentrations at a level of 0-4.1 g S m(-3) were applied by either addition or sulfate reduction. Results showed that wastewater in sewers was capable of biological, but not chemical, sulfide oxidation under anoxic conditions. Elemental sulfur was the end-product during the experiment. Nitrite accumulates in wastewater as an intermediate. The anoxic oxidation rates for fresh wastewater was 0.48 g S m(-3) h(-1) at pH 7.0 and 0.62 g S m(-3) h(-1) at pH 8.5, which accounted for less than 30% of the potential aerobic oxidation rates. A long-term anaerobic adaptation of the wastewater was found to inhibit the oxidation process.     

Selection of an ultraviolet disinfection system for a municipal wastewater treatment plant.

As part of an expansion to an average flow of 45.9 million gallons per day (174 mld), the Ypsilanti Community Utilities Authority wastewater treatment plant in the State of Michigan, USA, elected to install ultraviolet disinfection as a replacement for the existing chlorination process. This paper presents a unique methodology used in selecting the best system based on not only the life cycle costs, and O & M considerations but also the participation of the stakeholders. The Team members consisted of representatives of all departments at the Authority, and these Team members made the decision. The Team evaluated all criteria in the office, which was followed by verification at selected sites with similar types of equipment. The selected equipment then was pilot tested for validation of the dose-kill relationship under normal operation and also under reduced irradiation conditions. A low-pressure, high intensity system was selected, based on life-cycle cost, reliability, safety, and ease of operation. This paper describes the unique methodologies used in making that decision. The full-scale system is scheduled for start-up in Spring 2003.     

Dynamic monitoring system for full-scale wastewater treatment plants.

This paper proposes a new process monitoring method using dynamic independent component analysis (ICA), ICA is a recently developed technique to extract the hidden factors that underlie sets of measurements, whereas principal component analysis (PCA) is a dimensionality reduction technique in terms of capturing the variance of the data. Its goal is to find a linear representation of non-Gaussian data so that the components are statistically independent. PCA aims at finding PCs that are uncorrelated and are linear combinations of the observed variables, while ICA is designed to separate the ICs that are independent and constitute the observed variables. The dynamic ICA monitoring method is applying ICA to the augmenting matrix with time-lagged variables. The dynamic monitoring method was applied to detect and monitor disturbances in a full-scale biological wastewater treatment (WWTP), which is characterized by a variety of dynamic and non-Gaussian characteristics. The dynamic ICA method showed more powerful monitoring performance on a WWTP application than the dynamic PCA method since it can extract source signals which are independent of time and cross-correlation of variables.     

Ozone micro-bubble disinfection method for wastewater reuse system.

Reuse of wastewater is regarded as one important way to deal with the world's shortage of potable water. The authors focused on a disinfection system using micro-bubbles and evaluated its capability for wastewater reuse. This paper reports experimental results from examination of the basic characteristics of micro-bubbles and disinfection of secondary effluent by air or ozone micro-bubbles. The results suggest that when micro-bubbles are applied in an ozonation system it is possible to reduce the reactor size, the amount of ozone decomposition equipment needed and the ozone dose rate.     

DE型氧化沟在城市污水处理中的应用

以济南水质净化二厂为例分析DE型氧化沟处理城市污水的效果,对该厂2004年水质指标CODCr、BOD5、SS、TP、NH3-N的进出水浓度变化进行了分析,同时分析了1#氧化沟和3#氧化沟的MLSS、MLVSS、SV的月平均变化趋势。结果表明用DE型氧化沟处理城市污水具有较好的效果,能够达到《城镇污水处理厂污染物排放标准》(GB18918—2002)的二级标准。     

UASB-接触氧化工艺处理果汁废水

结合实际工程的运行情况,对UASB-接触氧化工艺在处理果汁废水中的应用状况进行了研究,并针对果汁废水特点,对UASB的快速启动进行了详细的分析.实践表明,该工艺对CODCr、BOD5、SS、NH3-N均有较高的去除率,出水水质达到《污水综合排放标准》(GB 8978-1996)一级标准.     

ICEAS-接触氧化工艺处理电器加工生产废水

采用反应沉淀-ICEAS-生物接触氧化-气浮-过滤工艺处理电器加工废水,该废水主要污染物为特氟隆及其他高分子有机物,且水质水量变化大.工程实践证明,经该工艺处理后出水CODCr28～46 mg/L,BOD5 5～8 mg/L,SS 2～4 mg/L,pH 6～9,出水水质达到<城市污水再生利用城市杂用水水质>(GB/T 18920-2002)标准,可回用作为绿化和冲洗厕所用水.     

混凝沉淀-ABR-接触氧化工艺处理纱线染整废水

采用混凝沉淀—ABR—接触氧化工艺处理纱线染整废水,并对工艺单元的特点和运行情况进行了分析。运行结果表明,混凝沉淀池对CODCr和色度的去除率分别为50.5%和76.9%;ABR和接触氧化池的容积负荷分别为0.73kgCODCr/(m3.d)和0.43kgCODCr/(m3.d);处理后出水CODCr<85.5mg/L,色度<40倍,系统对CODCr、BOD5、SS、色度和硫化物的平均去除率分别为89.8%、92.1%、82.8%、95.2%和99.2%。     

Non-specific monitoring to resolve intermittent pollutant problems associated with wastewater treatment and potable supply.

An online monitoring system based on an array of non-specific sensors was used for the detection of chemical pollutants in wastewater and water. By superimposing sensor profiles for defined sampling window, the identification of data points outside these normal sensor response patterns was used to represent potential pollution episodes or other abnormalities within the process stream. Principle component analysis supported the detection of outliers or rapid changes in the sensor responses as an indicator of chemical pollutants. A model based on the comparison of sensor relative responses to a moving average for a defined sample window was tested for detecting and identifying sudden changes in the online data over a 6-month period. These results show the technical advantages of using a non-specific based monitoring system that can respond to a range of chemical species, due to broad selectivity of the sensor compositions. The findings demonstrate how this non-invasive technique could be further developed to provide early warning systems for application at the inlet of wastewater treatment plants.     

Advanced oxidation of bleached eucalypt kraft pulp mill effluent.

In this study a poorly biodegradable (BOD/COD = 0.3) industrial alkaline ECF bleaching filtrate was treated using different advanced oxidation processes to evaluate their use in combined chemical-biological treatment aimed at increasing recalcitrant COD removal and improving final effluent quality. Oxidative treatments included ozonation combined with hydrogen peroxide (2, 5, 10, 20 mmol L(-1) O3/0.7, 2, 5, 10 mmol L(-1) H2O2) and photocatalysis with hydrogen peroxide (UV/2, 4 and 8 mmolL(-1) H2O2) and with TiO2 (UV/TiO2/0.7 and 4 mmol L(-1) H2O2). The O3/H2O2 process increased effluent biodegradability by up to 68% as a result of increasing BOD and decreasing COD. Increasing the O3 dose had a greater effect on biodegradability improvement and lignin and colour removal efficiencies than increasing the H2O2 dose. A combined oxidant dose of 5 mmol L(-1) O3 and 2 mmol L(-1) H2O2 resulted in 75% lignin removal, 40% colour removal and 6% carbohydrate loss without mineralizing the organic carbon. The photocatalytic processes led to a decrease in effluent biodegradability through combined decrease in BOD and increase in COD and did not result in efficient lignin or colour removal. Photocatalytic oxidation was apparently inhibited by the high chloride and COD levels in the alkaline filtrate, and may be more efficient in recalcitrant COD removal if performed after biological.     

Integrated airlift bioreactor system for on-site small wastewater treatment.

An integrated airlift bioreactor system was developed, which mainly consists of a multi-stage loop reactor and a gas-liquid-solid separation baffle and possesses dual functions as bioreactor and settler. This integrated system was used for on-site treatment of industrial glycol wastewater in lab-scale. The strategy of gradually increasing practical wastewater concentration while maintaining the co-substrate glucose wastewater concentration helped to accelerate the microbial acclimation process. Investigation of microbial acclimation, operation parameters evaluation and microbial observation has demonstrated the economical and technical feasibility of this integrated airlift bioreactor system for on-site small industrial wastewater treatment.