SCR脱硝催化剂再生技术的发展及应用

催化剂是SCR烟气脱硝技术的核心,其成本占整个SCR烟气脱硝系统投资成本的40%甚至更多。催化剂的性能直接决定了SCR烟气脱硝系统的脱硝效率和氮氧化物排放量、氨逃逸量、SO2/SO3转化率、系统压力、电能消耗、还原剂消耗等,一般工业应用的SCR催化剂的使用寿命为2.4万小时,逾期需要及时更换或进行再生。文章介绍了SCR脱硝催化剂再生技术的发展现状,分析了国内SCR催化剂再生技术的发展前景,并列举了催化剂再生技术的应用案例。     

高性能Pt—Rh型汽车尾气净化三效催化剂的研制

本文报导了以高性能稀土储氧材料为基础、制备出高性能高耐久性的Pt-Rh型三效催化剂,经过8万公里快速老化实验,催化剂仍保持高活性和高稳定性。     

SCR催化剂的碱金属中毒研究

催化剂是选择性催化还原（SCR）系统的重要组成部分，催化剂的寿命决定着SCR系统的运行成本，研究催化剂中毒的原因，延长催化剂的使用寿命对降低SCR系统的运行费用意义重大。本文介绍了SCR脱除氮氧化物的基本原理，并讨论了导致催化剂中毒的各种原因。     

端视ICP-AES测定饮用水中的13种金属元素

本法研究了在饮用水使用端视ICP－AES直接测定水中的钙、镁、锂、锶、钡、铝、铁、锰、铜、锌、镉、铅、银元素。该方法操作简单，结果准确，具有良好的精密度和回收率。     

溶胶凝胶法制备铜催化剂及其稳定性的研究

介绍了利用溶胶凝胶方法制备铜系催化剂，并考察了制备过程中各个工艺参数对铜系催化剂稳定性的影响。通过优化催化剂的设计和制备方法，可有效地改善Cu^2＋的溶出问题，使该类催化剂具有广阔的应用前景。     

光解法降解含萘污水的实验研究

分别以６Ｗ主波长为２６５ｍｍ的低压汞灯和３００Ｗ的高压汞灯为光源,对模拟污水中的萘进行了紫外光直接光解和ＴｉＯ２催化光解的可行性进行了研究。通过对催化剂吸附作用、体系溶氧、无机酸、碱和催化剂剂量等因素对萘光解反应影响的考察,证明紫外光光解法能够使模拟污水中的萘快速、有效地进行降解,并表明萘的ＴｉＯ２催化光解与其直接光解相比并无明显的优越性。光解反应速率方程符合一级反应动力学性质。     

疏水催化剂用于水中氚回收的实验研究

本文简要介绍了自制的几种疏水催化剂的主要特性，采用这些催化剂进行了室温下的Ｈ－Ｔ同位素交换实验，初步考察了氢气流速对催化活性的影响。实验表明，催化剂的催化活性较高，能够用于室温下从氚水中回收氚     

SCR脱硝催化剂反应活性探讨

随着我国对环保要求以及对氮氧化物排放指标要求的不断趋严,选择性催化还原(SCR)脱硝技术在我国得到了广泛的应用,选择性催化还原(SCR)脱硝催化剂性能的好坏直接关系到脱硝系统的运行效果。通过对实际生产中因积灰堵塞、磨损和中毒使催化剂失活的原因分析,提出了在设计和运行等方面的优化措施。     

汽车尾气催化剂的发展

文章介绍了汽车尾气催化净化的发展简史，概述了三效催化剂的组成及相关性能和制备方法，分析了汽车尾气三效催化剂技术发展热点和趋势。     

B/Fe2O3共掺杂纳米TiO2可见光下催化性能研究

采用溶胶-凝胶法制备了B／Fe2O3共掺杂TiO2复合光催化材料，并用XRD、荧光光谱（FS）和紫外可见漫反射光谱（DRS）对粉体进行了表征。XRD显示催化剂以锐钛矿存在的纳米颗粒，硒显示了颗粒的光谱特征，DRS显示掺杂B能极大提高催化剂可见光响应。以2，4-二氯苯酚（DCP）为降解物质，在紫外和可见光下分别研究了复合催化剂的光催化活性。结果表明，掺杂B能使吸收光谱红移至可见光区，而进一步掺杂Fe203大大提高了催化剂的活性。     

PUBLIC PERCEPTIONS IN WATER QUALITY EVALUATION1

ABSTRACT: A Visual Perception Test, consisting of photographic slides of water sites, was designed to examine laymen's water quality perceptions. The slides were taken at five water sites where the level of visual pollution was artifically altered by the investigator. Analysis of variance indicated that the water sites were evaluated differently for each of five pollution levels. Increases in water discoloration and the quality of litter were viewed as increases in level of pollution. Laymen not only evaluated visually polluted sites lower for uses such as picnicking, but they also evaluated the quality of the actual water lower. Stepwise multiple regression indicated that a combination of water color, scenic beauty appreciation, quality of the surrounding environment and industry as a pollution source explained 73 percent of the variance in predicting Overall Pollution. Application of factor analysis simplified the variables to an Overall Pollution Factor and a Boating Use Factor.     

THE W-INDEX FOR RESIDENTIAL WATER CONSERVATION1

ABSTRACT: An index of residential water efficiency - a “W-Index” - can serve as a measure of effectiveness of water conservation features in the home. The index provides a calculated numerical value for each dwelling unit, derived from the number and kind of water-saving features present, including indoor and outdoor water savers and water harvesting or recycling systems. A W-Index worksheet, devised for on-site evaluation of single-family residences in the Tucson, Arizona, region shows that a nonconserving residence with all the water-using features would use 151,000 gallons per year or 148 gallons per capita per day (gpcpd), while the fully conserving model would use 35,300 gallons per year or 35 gpcpd and with water harvesting and graywater recycling systems would have a maximum W-Index of W-160. A Tucson water conservation demonstration home, Casa del Agua, received a rating of W-139, and field tests of about 30 homes in new Tucson subdivisions show values ranging from W-75 to W-100, indicating the incorporation of some water conservation in current new models. By adjustment of some climatic or water-use parameters, the W-Index format can be applied to various types of dwelling units or to other urban areas. The W-Index can be used by individual homeowners or builders to evaluate water efficiency of residential units, or by water providers or water management agencies as a device for promoting and achieving water conservation goals.     

RATIONAL INDUSTRIAL WATER REUSE RATIOS1

ABSTRACT: This work begins by defining rational water use, and then discusses important factors that most strongly influence it. A general model is then developed to enable factories to quantify the ratio of rational industrial water reuse based on the least cost method. The model is established to minimize the cost of water with reference to gross water use and three subsystems ‐ the intake, reuse, and discharge of industrial water. Discharge cost is determined using data from a 1997 survey of 38 factories, and reuse costs are ranked and expressed by a step function. The model is verified using data from a typical semiconductor factory in northern Taiwan's Hsinchu Science Based Industrial Park, whose effective rational water reuse ratio is about 38 percent. A sensitivity analysis shows that improving water reuse technology is the most important factor in determining the rational water reuse ratio, and the price of water is the second most important. When water costs over NT$30 (New Taiwan Dollar, US$1 = NT$34) per cubic meter, increasing reuse becomes significant. The model provides a step towards the scientific management of industrial water.     

MEETING FUTURE PUBLIC WATER SUPPLY NEEDS: A SOUTHWEST PERSPECTIVE1

ABSTRACT: Most southwestern cities were founded along rivers or in areas having springs or readily available ground water. Because of the generally sparse precipitation, the renewable fresh water supply in the Southwest is smaller than most other areas of the United States. Despite the arid climate, water use has increased rapidly, first in the form of irrigation, and more recently the use in cities. This has caused extensive development of local water resources and overdraft of ground water basins in some areas. It is difficult to implement new local supplies and importation projects due to a myriad of environmental and legal constraints and a general shortage of public funds. Various opportunities and plans for water management, both on the demand and supply sides, are discussed. Evolving water strategies in four metropolitan areas - El Paso, Albuquerque, Las Vegas, and Phoenix - and issues regarding the Central Arizona Project are presented.     

POTENTIAL BENEFITS AND COSTS OF INGROUND STORAGE OF IMPORTED WATER1

ABSTRACT: In the near future, groundwater storage of imported water may become increasingly important as sites for surface storage are less available. This article explores the potential economic costs and benefits of groundwater storage. The costs include capital outlays, maintenance costs, land costs, legal costs, energy costs, and opportunity costs. The benefits include land cost savings, prevention of subsidence, aquifer protection, and higher economic use of surface lands that might be covered by a reservoir.     

The Water Market for the Middle and Lower Portions of the Texas Rio Grande Basin1

Leidner, Andrew J., M. Edward Rister, Ronald D. Lacewell, and Allen W. Sturdivant, 2011. The Water Market for the Middle and Lower Portions of the Texas Rio Grande Basin. Journal of the American Water Resources Association (JAWRA) 47(3):597‐610. DOI: 10.1111/j.1752‐1688.2011.00527.x Abstract: Regional water management on the United States’ side of the middle and lower portions of the Rio Grande basin of Texas has been aided by a functioning water market since the early 1970s. The water market operates over a region that stretches from the Amistad Reservoir to the Rio Grande’s terminus into the Gulf of Mexico. This article provides an overview of the organizations, institutions, policies, and geographic particulars of the region’s water‐management system and its water market. In recent years, this region has experienced high population growth, periodic droughts, and a reallocation of water resources from the area’s agricultural sector to the municipal sector. Demand growth for potable water and a relatively fixed supply of raw water are reflected in increasing prices for domestic, municipal, and industrial water rights. Rising prices in the presence of scarcity and the transfer of water from lower‐value to higher‐value uses indicate that the market is operating as suggested by economic theory. Reasons for the market’s functionality are presented and discussed. Finally, suggestions are presented which might mitigate potential complications to market operations from aquifer depletion and aid the management of instream river flows.     

水资源短缺的有效解决途径——虚拟水战略

针对中国水资源利用现状，系统论述了水足迹、虚拟水以及虚拟水战略的概念和内涵。通过水足迹来揭示人类对水资源的实际需求和占用，介绍了虚拟水战略的研究展望及存在的不足，通过应用虚拟水战略可以缓解水资源短缺现状，保证水资源与人口、耕地的地域组合均衡。     

WATER MANAGEMENT ISSUES FOR THE NINETIES1

ABSTRACT: This paper summarizes contemporary water management issues as recognized by 19 U.S. organizations. Only the issues are identified herein. Individual organization stands are not presented. Most suggestions for action are those of the author. Addresses of all organizations whose documents were reviewed are included in the Reference section so that those desiring to learn more about an organization's stand can readily make contact.     

WATER USE RELATIONSHIPS AND PROJECTION CORRESPONDING WITH REGIONAL GROWTH,SEATTLE REGION1

ABSTRACT: The paper outlines both the methods used and the results obtained in a study of the demand for municipal and industrial water for the Seattle region. The study was made as part of a regional water management study program, one objective of which is to “… identify, quantify, and set priorities for all current and future water uses …”. A basic concept in the study of municipal and industrial water use is that the demand for water is derived from the demand for output and the direct services that water provides. Principal characteristics of the study are: (1) Water use is studied by type - residential, commercial, industrial and public -with identification of factors affecting each; (2) Water demands are studied by season as well as on an annual basis; (3) Projections of future water use are tied directly to projections of economic change in the service area; and (4) The effects of alternative policies on water use are estimated. Water use levels are projected under alternative regional growth assumptions provided by the Puget Sound Governmental Conference, a regional planning agency. Thus, the water use planning is consistent with other regional planning programs in this respect. The results can be varied according to changes in specific factors affecting water use. The factors considered in the present study include: single-family residential lot size, distribution of population between single- and multi-family units, per capita water use by multi-family unit residents, and industrial and commercial water use per employee. An income elasticity of demand was estimated for single-family residential water use.     

Price Determination and Efficiency in the Market for South Platte Basin Ditch Company Shares

Water scarcity presents an obstacle to economic development in the western United States. Water rights markets help improve water allocation, allowing states to derive the highest economic benefit from available resources, and supporting new uses and economic development. However, the implicit (marginal) prices of water rights attributes are uncertain. To address this problem, we apply econometric analysis to a unique dataset to estimate the implicit values that market participants place on the attributes of shares of ditch company water rights in Colorado's South Platte River Basin. Our analysis demonstrates that ditch company share buyers value proximity of water diversion, reliability of water deliveries, and temporal flexibility of water use. To assess reliability we introduce the use of the coefficient of variation to capture, in one variable, the randomness of supply from ditch company shares that are not a single water right, but a portfolio of rights with different appropriation dates. Finally, we test and correct for spatial autocorrelation for the first time in a study of water market prices.