鲁西北地区渍涝洼地人工鱼塘─台田的环境分析

鲁西北地区是黄淮海平原中低产田渍涝洼地的主要分布区之一。在鲁西北的禹城市，利用挖鱼塘、建台田的工程措施，综合改造利用这类洼地。工程实施后，通过水盐调控，改善了洼地的环境状况。监测结果表明：洼地台田土壤含盐量降低，土壤逐渐熟化。土壤有机质大量整治前后分别为０．５８２％（１９８６年）、０．９８９％（１９８９年）．土壤中的全氮、全磷也由整冶前的０．０２％、０．１４％上升到整治后的０．０６１％和０．１５８％。土壤盐分含量逐年降低，由０．５０～０．９２％下降到０．０６～Ｏ２９％。挖鱼塘建台田的生态工程措施，使浅层地下水地表化，解决了洼地积水蒸发等形成的盐渍化问题。综合环境效应显示，洼地原有的自然状况向良性转化，达到了初步治理的目的。     

水处理氧化还原过程的电动化学特性

以流动电流为参数,研究了水处理条件下氧化还原过程的电动化学特性.考察了水中KMnO_4及其与Mn~(2+),Fe~(2+)之间氧化还原作用的流动电流(SC)规律,探讨了氧化还原的初始条件、水处理环境、原水水质、氧化剂与还原剂的投加方式等对流动电流的影响.结果表明,水中约0.5mg·l~(-1)的KMnO_4可产生SC的峰值,而且当它与Mn~(2+)和Fe~(2+)经不同条件进行氧化还原作用时,可通过SC值的变化表现出更为明显的电动化学特性.     

Cyclohexane oxidation and carbon deposition over metal oxide catalysts

Catalytic activity of V, Mn, Ni, Cu, Zn, Mo, Zr and Ce oxides over an -alumina support was evaluated for cyclohexane oxidation under oxygen deficient conditions in order to understand the relation between carbon deposition and catalytic activity/selectivity. Carbon formation over the catalysts during the oxidation reaction was measured by means of Fourier transformed infrared spectroscopy (FTIR). Catalysts Mn/Al₂O₃ and Ce/Al₂O₃, which are selective for deep oxidation of cyclohexane, possessed relatively carbon free surfaces. The catalysts with relatively high carbon deposition (V, Ni, Cu, Zn, Mo and Zr) produced CO in addition to CO₂. Traces of formaldehyde were produced over the catalysts Mo and V.     

污泥颗粒化快速启动厌氧氨氧化反应器的探讨

厌氧氨氧化工艺处理成本低,被认为是有应用前景的废水脱氮技术.但是,厌氧氨氧化菌生长缓慢,厌氧氨氧化反应器启动困难.探讨了几种快速启动厌氧氨氧化反应器的方法,包括投加颗粒污泥、惰性载体、絮凝剂及多价阳离子等,并对其作用机理进行了分析.     

前处理-水解-生物接触氧化工艺处理染料废水

介绍了前处理-水解-生物接触氧化工艺处理染料废水的工程实例.当进水COD≤8000 mg/L时,出水可达到国家<污水综合排放标准>(GB8978-1996)二级标准.     

炼油厂含油冷却水处理回用技术研究

开展了O3 氧化和强碱性阴离子交换组合工艺用于炼油厂含油冷却水回用处理的实验研究。结果表明 ,O3 氧化过程中的最佳pH值约为 10 .5 ,O3 氧化的除油效率为 86 .7% (紫外法测定 ) ,去除 1mg石油类约需消耗 5 .7mgO3 ,O3 氧化后产物以乙酸和丙酸等挥发性脂肪酸为主。离子交换处理后油的含量达到未检出的水平。研究结果表明 ,O3 氧化和离子交换组合处理技术能使炼油厂含油冷却水达到回用水水质标准。     

生物接触氧化-电凝聚复合工艺处理垃圾渗滤液

为了探索高效垃圾渗滤液处理工艺,采用生物接触氧化-电凝聚复合工艺处理垃圾渗滤液.试验结果表明,本工艺适于处理COD＜5000 mg/L的垃圾渗滤液,最高容积负荷可达6.56 kgCOD/m3·d,COD去除率最高可达84.63%,平均BOD去除率可达91.25%,NH4-N去除率最高可达86.13%,处理后的垃圾渗滤液可达到国家污水二级排放标准,电耗为9元/m3水,铁耗为1元/m3水.     

臭氧在污泥减量技术中的应用

大量的剩余污泥已成为国内外污水处理行业亟待解决的问题,因此各种物理、化学和生物方法被应用到污泥处理中,臭氧以其独特的性质从一开始应用就备受青睐.详细地说明了臭氧在污泥减量技术中应用的背景及原理,重点介绍了臭氧对污泥性质的影响,并分别从臭氧氧化技术与传统活性污泥法组合、与AO工艺组合、与膜生物反应器(MBR)组合、与磷回收工艺组合、与SBR工艺组合等角度分析了臭氧在污泥减量技术中的应用与现状、目前存在的问题及未来的发展方向.     

Water technology for specific water usage

BACKGROUND: Water is the basis for life and culture. In addition to the availability of water its quality has become a major issue in industrialized areas and in developing countries as well. Water usage has to be seen as part of the hydrological cycle. As a consequence water management has to be sustainable. The aim of the contribution is to give water usage oriented quality criteria and to focus on the technical means to achieve them. MAIN FEATURES: Water is used for many purposes, ranging from drinking and irrigation to a broad variety of technical processes. Most applications need specific hygienic, chemical and/or physical properties. RESULTS: To meet these demands separation and reaction principles are applied. The reuse of water and the application of water treatment with little or no waste and by-product formation is the way to go. Membrane separation and advanced oxidation including catalytic reactions are promising methods that apply natural processes in sustainable technical performance. Thus elimination of specific water constituents (e.g. salts and metals, microorganisms) and waste water cleaning (e.g. pollutants, nutrients and organic water) can be done efficiently. OUTLOOK: Learning from nature and helping nature with appropriate technology is a convincing strategy for sustainable water management.     

Formation of Nitrate and Sulfate in the Plume of Berlin (8 pp)

Background, Aims and Scope Secondary inorganic aerosol (SIA), i.e. particulate sulphate (S(VI)), ammonium and nitrate (N(V)) is formed from gaseous precursors i.e., sulfur dioxide (S(IV)), ammonia and nitrogen oxides, in polluted air on the time-scale of hours to days. Besides particulate ammonium and nitrate, the respective gaseous species ammonia and nitric acid can be formed, too. SIA contributes significantly to elevated levels of respirable particulate matter in urban areas and in strongly anthropogenically influenced air in general. Methods The near-ground aerosol chemical composition was studied at two stationary sites in the vicinity of Berlin during a field campaign in summer 1998. By means of analysis of the wind field, two episodes were identified which allow to study changes within individual air masses during transport i.e., a Lagrangian type of experiment, with one station being upwind and the other downwind of the city. By reference to a passive tracer (Na+) and estimates on dry depositional losses, the influences of dispersion and mixing on concentration changes can be eliminated from the data analysis. Results and Discussion Chemical changes in N(-III), N(V) and S(VI) species were observed. SIA i.e., N(V) and S(VI), was formed from emissions in the city within a few hours. The significance of emissions in the city was furthermore confirmed by missing SIA formation in the case of transport around the city. For the two episodes, SIA formation rates could be derived, albeit not more precise than by an order of magnitude. N(V) formation rates were between 1.4 and 20 and between 1.9 and 59 % h-1 on the two days, respectively, and S(VI) formation rates were > 17 and > 10 % h-1. The area south of the city was identified as a source of ammonia. Conclusion The probability of occurrence of situations during which the downwind site (50 km downwind of Berlin) would be hit by an urban plume is > 7.4%. Furthermore, for the general case of rural areas in Germany it is estimated that for more than half of these there is a significant probability to be hit by an urban plume (> 8%). The S(VI) formation rates are higher than explainable by homogeneous gas-phase chemistry and suggest the involvement of heterogeneous reactions of aerosol particles. Recommendation and Outlook The possible contribution of heterogeneous processes to S(VI) formation should be addressed in laboratory studies. Measurements at more than two sites could improve the potential of Lagrangian field experiments for the quantification of atmospheric chemical transformations, if a second downwind site is chosen in such a way that, at least under particular stability conditions, measurements there are representative for the source area.