北京某数据中心全年用水量分析

介绍了北京某数据中心用水量设计及运行的工程实例,以全年用水量的实测数据为基础进行研究,计算数据中心的水资源使用效率实测值,分别探讨了冷却塔补水量对用水量的影响以及蒸发损失、浓缩倍数、冷却水循环水量、制冷系统自然冷却时间对冷却塔补水的影响,最后给出了在数据中心水资源容量规划、冷却循环水补水系数取值及冷却水补水储存容量估算时的具体建议。     

中小型抽风逆流式冷却塔防冻措施

目前,中小型冷却塔已作为产品供应,工程建设中只需选型、配置水池和管道。这样,在气候寒冷地区冬季使用冷却塔往往会发生结冰现象,达是普遍存在的问题。在我厂12500KVA硅铁电炉循环冷却水系统中,设置了ZBL_2—300型抽风逆流式玻璃钢冷却塔(以下简称冷却塔),每台冷却水量为300吨/时,其布置安装形式如图1所示。我厂所处西宁市的历年最冷月平均温度为-9℃,属寒冷地区。冷却塔在冬季运     

寒冷地区冷却塔防冰新技术

寒冷地区冷却塔冬季运行时结冰现象严重，给安全生产和操作维护都带来许多困难。介绍了防止冷却塔进风百叶窗和外层填料处结冰的新技术及其实际应用效果。     

核电厂抗震机械通风冷却塔防冻技术探讨

寒冷地区核电厂抗震机械通风冷却塔冬季运行中的最大危害是冷却塔结冰,尤其是处于严寒地区的冷却塔。通过对电厂中冷却塔的运行经验的调研,结合核电厂抗震机械通风冷却塔的特殊性,分析冷却塔易结冰部位,找出结冰原因,分析结冰产生的危害,提出针对核电厂抗震机械通风冷却塔的防冻措施。     

大型冷却塔防护间距的探讨

本文叙述了冷却塔防护间距现行国家标准的来历和确定冷却塔防护间距的主要因素，根据冷却塔收水器效率的提高、实测风吹水量的减少和对冷却塔现状的调查，对国家标准规定的冷却塔与相邻设施的防护间距进行了探讨，提出冷却塔防护间距应根据环境条件、气候差异而不同，还应随着技术的发展适时修订。     

发电厂排烟冷却塔防腐体系设计

华电天津军粮城发电有限公司五期2×350MW供热机组工程采用排烟冷却塔技术,详细分析了排烟冷却塔的腐蚀机理,指出采用防腐涂层是目前国内较实用的防腐途径。介绍了防腐体系选择的原则及防腐施工中应注意的问题,从根本上提高防腐质量。     

循环冷却水系统的节能与冷却塔供冷技术

探讨了建筑循环冷却水系统中的节能途径,对冷却水水源、系统、冷却塔的选择和设置、水处理、计量与控制、余热利用与冷却塔供冷等方面提出了具体的节能方法。重点介绍了冷却塔供冷技术的节能方法,包括冷却塔供冷的形式和设计中需注意的问题,并介绍了系统中运用的三通阀。     

填料支承方式对冷却塔面积的影响分析

针对冷却塔悬吊式和搁置式两种填料支承方式,会导致淋水填料层有效通风面积和通风阻力有所不同,在冷却塔总体热力性能相当的条件下,探讨了其对冷却塔淋水层面积(冷却塔面积)的影响。以某1 000MW机组电站为例,对两种填料支承方式进行对比分析,为冷却塔填料的支承方式选择提供借鉴和参考。     

玻璃钢烟道在排烟冷却塔中的应用

介绍了排烟冷却塔在国内外的发展情况。论述了华电天津军粮城发电有限公司五期2×350MW供热机组工程排烟冷却塔工艺流程和烟气设计参数，重点阐明了玻璃钢烟道的选择、玻璃钢烟道的性能及其加工制作技术要求。华电天津军粮城发电有限公司冷却塔玻璃钢烟道的应用经验，可为使用同类冷却塔玻璃钢烟道的电厂提供参考和借鉴。     

超大型双曲冷却塔考虑不同场地类型的地震性能研究

当不具备直流冷却条件时,工业生产过程中产生的废热,需要用冷却塔来冷却。本文研究的超大型双曲冷却塔是火电厂中循环冷却水的重要建筑物,其高度达到250 m,底部直径也达到了200 m。其高度远远超过规范"冷却塔高度≤150 m"的限制。由于规模较大,冷却塔的抗震性能就变得更加重要。本文对超大型冷却塔结构进行模态分析、地震作用分析,并比较不同场地类型下的结构地震响应,分析结果显示:冷却塔受力敏感部位为塔身底部和喉部,应作为重点考察其受力与变形;冷却塔地震作用受场地影响较大,应避免在不利场地条件下选址。     

Call for Papers

正As the eldest and most distributed professional journal of water industry,Water Wastewater Engineering(W WE)gained very wide acceptance from the colleagues working in this field in this country since start publication in 1964.Now it is administrated by the Ministry of Construction of the People’s Republic of China and sponsored by the China Civil Engineering Society etc.     

Serial discontinuities in a Rocky mountain river. I. Distribution and abundance of plecoptera

Samples were taken year-round at eleven sites along the altitudinal profile (2900-1400 m a.s.l.) of the Gunnison River, a 329 km tributary of the Colorado River, to document the distribution of the Plecoptera and to evaluate responses to hypolimnial-release dams in the headwaters and middle reaches. Twenty-two species were present, with the greatest species richness occurring in an unregulated segment upstream of the middle reach dams; average nymphal biomass over the study period (175 organisms, 395 mg dry mass m^?2) was also greatest in this segment. Only four species (58 organisms, 48 mg m^?2) were present in the tailwaters of the headwater dam and values were greatly reduced (nine species; 35 organisms, 180 mg m^?2) below the middle reach dams. The stonefly community recovered ca. 80 km downstream from the last dam (15 species; 244 organisms, 250 mg m^?2), apparently in response to natural resetting of environmental conditions corresponding to those above the middle reach dams. At the most downstream site (11) only four species (four organisms, 16 mg m^?2) were present. The observed distributional pattern is a classic serial discontinuity in response to hypolimnial stream regulation in a temperate latitude river.     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Impacts of Microcystis on algal biodiversity and use of new technology to remove Microcystis and dissolved nutrients

Cyanobacteria often dominate eutrophic lakes, outcompeting green algae that are required by fish and zooplankton. This study was undertaken to ascertain the impact of the cyanobacterium, Microcystis, on algal biodiversity. Under laboratory conditions, we found that the presence of Microcystis decreased phyla richness by 58%, phyla evenness by 47%, genera richness by 66% and genera evenness by 51%. Analysis by mixed anova s demonstrated a significant interaction between treatment and time and confirmed a significant reduction in richness and evenness of phyla and genera. We also conducted a phosphate restriction assay on the algae in Mason Lake (Irvine, CA, USA) and found that the threshold needed for algal growth there was 0.02 mg L^?1 PO₄. A pilot study was then conducted to test the effectiveness of the Blue Pro? water treatment facility in removal of this colonial organism from Mason Lake, in addition to removal of dissolved nutrients required for its growth. We measured a 97% reduction in Microcystis cells, a 72% reduction in chlorophyll‐a, and a 96% reduction in phosphate after just one 10 min cycle through the unit. Our study demonstrated that removal of Microcystis colonies may allow green algae to increase in numbers. This may improve algal biodiversity, which will benefit zooplankton and fishes.     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

SPATIAL AND TEMPORAL WATER QUALITY VARIABILITY IN AQUATIC HABITATS OF A CULTIVATED FLOODPLAIN

The floodplains of lowland rivers contain diverse aquatic habitats that provide valuable ecosystem services but are perturbed when intensively cultivated. Hydrologic, water chemistry and biological (fish) conditions in five aquatic habitats along the Coldwater River, Mississippi, were measured for more than 4 years: the river, two severed meanders that functioned as backwaters, a managed wetland and an ephemeral channel draining cultivated fields. Off‐channel habitats were connected to downstream regions 0.10% to 32% of the dry season and 24% to 67% of the wet season. The median temperatures for the five monitored sites ranged from 18°C to 23°C, the median total solids concentration for all sites was 135 mg L^?1, the median total phosphorus was 0.29 mg L^?1 and the median total nitrogen was 1.56 mg L^?1. Chemical and physical water quality displayed strong seasonal differences between the wet winter/spring and the dry summer/fall periods so that temporal variation consisted of gradual seasonal trends superimposed on strong diurnal variations. All off‐channel habitats exhibited periods of hypoxia and temperatures >30°C during the dry season. Between‐site gradients of water and habitat quality were strongly coupled to water depth and runoff loading. The rehabilitation of one backwater by increasing water depth and diverting agricultural runoff was associated with improved water quality and fish species richness relative to an adjacent untreated backwater. The diversion of polluted runoff and the use of water control structures to maintain greater water depth were observed to be effective management tools, but the former reduces the water supply to habitats that tend to dry up and the latter reduces connectivity. Published in 2011 by John Wiley & Sons, Ltd.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

簸箕李引黄灌区水沙分布及优化调度的经验

灌区利用水沙观测所取得的资料和试验数据，运用水沙运动力学理论，总结分析和揭示了灌区水沙分布的规律和特点。在此基础上，结合灌区的实际运行情况，围绕减少骨干渠道的淤积进行探讨、研究，进而，优化水沙调度方案。该方案实施后，骨干渠道减旅伴效果明显，取得了成功的经验。     

小湾水库大坝防渗面板及其裂缝的加固处理

小湾水库大坝防渗面板整体抗渗性能差,且存在多条裂缝,通过对面板钢丝网喷涂丙乳砂浆加固处理及其裂缝修补,大坝渗漏量明显减少,且左岸上灌浆廊道内及大坝下游坝面92～93 m高程下廊道入口处原有小股射流全部消失.     

Automated system for removal and pneumatic transport of fly ash from electric precipitator hoppers

A system for removal and pneumatic transport of fly ash is examined, in which air pulses act on batches (pistons) of ash formed in a duct. Studies are made of the effect of several physical parameters on the force required to displace a piston of ash and these serve as a basis for choosing a system for removal and pneumatic transport of ash simultaneously from several hoppers of an electric precipitator. This makes it possible to separate the ash particles according to size without introducing additional components. Formulas are given for calculating the structural and dynamic parameters of this system and measurements of indirect dynamic parameters are used to calculate the input-output characteristics of the system. In order to optimize the system, configurations for summing several ducts into a single transport duct for pneumatic ash transport are proposed. Some variants of dry ash utilization and the advantages of producing of size-separated particles are considered. __________ Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008).