含硫气田设备及管道的腐蚀与防腐

四川气田系我国典型的含硫气田,设备及管道的腐蚀与防腐问题一直是一个重要的研究课题。文章首先分别探讨了H_2S腐蚀和CO_2腐蚀的机理及其影响因素,进而提出了H_2S和CO_2的防腐工艺和措施,最后探讨了含硫气田腐蚀及防腐研究的热点和发展方向,指出应该大力开展高含硫气田的腐蚀和防腐技术、二氧化碳条件下的钢材腐蚀机理和防腐技术、细菌腐蚀以及新型合金材料及非金属管道的应用研究,同时进行防腐实验。     

水体穿越输油管道腐蚀检测及泄漏后果模拟

为了解管道腐蚀状况,对管道所处的土壤环境进行了分析,对管道外防腐层进行了土壤腐蚀性检测、外防腐层检测,对管道的内腐蚀状况以及管道腐蚀破坏后造成的泄漏后果进行了模拟分析。结果表明:管道发生腐蚀的风险较大,为此对管道防腐工作提出了建议。     

大气污染对起重机械的腐蚀与防腐措施

本语文主要介绍了在腐蚀性介质环境中工作的起重机械被腐蚀的原因及形成机理,进而提出了在用起重机械防腐控制的措施。     

湿法烟气脱硫中烟囱腐蚀及其防腐材料研究现状

介绍了湿法烟气脱硫(WFGD)机理及烟气脱硫处理过程,分析了WFGD处理烟气后引起烟囱严重腐蚀的相关问题.同时,系统地介绍了目前解决烟囱腐蚀的相关防腐材料,并叙述了相关重防腐处理工艺.     

典型乘用车整车道路强化腐蚀试验方法对比分析

整车道路强化腐蚀试验是汽车防腐质量控制体系中的核心工作,本文对比分析了美系、欧系以及自主品牌汽车典型道路强化腐蚀试验方法的差异,解读国际知名汽车企业整车道路强化腐蚀试验方法制定的依据,为我国自主品牌汽车企业尤其是新能源汽车企业开发适应全球不同腐蚀环境、腐蚀环境因素来源以及腐蚀控制目标的汽车整车提供技术借鉴。     

整车道路腐蚀试验的统计结果与分析

通过统计近几年来国内外各企业在海南试验场进行的整车道路腐蚀试验结果,进行分类对比分析,得出相关结论,为整车防腐工艺设计和道路腐蚀试验结果评价提供辅助参考。     

不同品牌汽车的零部件及材料加速腐蚀试验方法及评价对标分析

随着汽车工业的发展,汽车防腐日渐成为汽车制造及使用中的一个重要部分,汽车防腐技术的发展对于车辆的使用具有重要意义。加速腐蚀试验是指通过模拟材料所处的环境,通过加速腐蚀演示的方法来评价材料的耐蚀性,进而检测零部件和材料的性能。文章通过对美系汽车、日系汽车、欧系汽车等的加速腐蚀试验方法和标准的分析,为车企在相关试验方法的选择上做一些建议。     

吉林油田X区块腐蚀防护技术研究及应用

吉林油田X区块腐蚀结垢严重,造成的环境污染及安全生产隐患越来越突出。文章以X区块为研究对象,通过常规水质测定、高温高压釜失重法、气相色谱、XRD衍射分析等方法研究了矿化度、SRB细菌、CO2分压等腐蚀因素对区块注采系统腐蚀的影响。结果表明在X区块工况条件下,空白水样腐蚀速率达到0.3854mm/a,注水系统以CO2和SRB细菌腐蚀为主,油井以CO2腐蚀为主,SRB腐蚀为辅。以此为基础研发了抗CO2缓蚀杀菌剂体系,同时开展了涂层防腐工艺的试验,矿场监测数据表明注采系统腐蚀速率控制在0.076mm/a以内,失效漏失次数降低40％以上,减轻了环境污染,保障了老油田的安全高效生产。     

基于猪场环境下空调器腐蚀原因分析

针对空调在猪场养殖环境中频繁出现故障的问题,急需找出失效原因以此改进空调的防腐性能。通过现场走访调研,对故障空调部件的腐蚀形貌的观察及其腐蚀产物的分析,猪场有害气体采集分析以及腐蚀机理研究,找出引起空调腐蚀的主要原因。结果表明：铜管和镀锌钢支架腐蚀产物主要为氧化物和硫化物;空调服役的环境存在一定含量的硫化氢、二氧化硫、氨气和二氧化氮等有害气体。空调的腐蚀主要是由于猪舍“微环境”存在有害气体和较高湿度造成,需要对空调关键部件及材料的耐腐蚀性进行改善才能提高空调在猪场养殖环境的使用寿命。     

氨法烟气脱硫装置氟腐蚀分析及防护

氨法脱硫装置玻璃钢防腐层以及钛合金材质设备发生严重腐蚀,影响装置长周期运行。通过对腐蚀部位介质和装置来料进行化验分析,得出硫酸铵浆液中含大量氟离子。分析氟离子在装置内的聚集过程,研究氢氟酸在多种酸混合溶液中对二氧化硅和钛合金材料的腐蚀机理,为预防装置氟腐蚀提供理论依据。提出建立氟离子监控指标、增加烟气净化除氟前置单元、含氟过高部位采用2507双相钢材料等措施提高装置抗氟腐蚀能力。     

Conversion of temperate forests into heaths: Role of ecosystem disturbance and ericaceous plants

Fire and logging in nutrient-poor temperate forests with certain ericaceous understory plants may convert the forests into heaths. The process of disturbance-induced heath formation is documented by using examples ofCalluna in western Europe,Kalmia in Newfoundland, andGaultheria (salal) in coastal British Columbia. In a cool, temperate climate, rapid vegetative growth ofCalluna, Kalmia, and salal following disturbance results in increasing organic accumulation (paludification), nutrient sequestration, soil acidification, and allelochemicals. These are thought to be the main reasons to conifer regeneration failure in disturbed habitats. If continuation in forest is a land-use objective, then temperate forests with an ericaceous understory should not be logged unless effective silvicultural methods are devised to control the ericaceous plants and restore forest regeneration. Preharvest vegetation control may be considered as an option. Failure to control the understory plants may lead to a long-term vegetation shift, from forest to heathland, particularly in nutrient-poor sites. Successful methods of controllingKalmia andGaultheria, however, have yet to be developed. While theKalmia- andGaultheria- dominated heathlands are undesirable in Canada and the Pacific Northwest, a wide range ofCalluna heathlands of western Europe are being conserved as natural and seminatural vegetation.     

AN APPLICATION RUNOFF MODEL STRATEGY FOR UNGAGED WATERSHEDS1

ABSTRACT: Mathematical models for predicting watershed surface flow responses are available, most of which are elaborate nonlinear numerical surface and channel flow models linked with infiltration models. Such models may be used to make predictions for ungaged areas, assuming an acceptable fitting of the model to the topography and roughness of the real system. For some application purposes, these models are impractical because of their complexity and expensive computer solutions. A procedure is developed that uses a complex model of an ungaged area to derive a simpler parametric nonlinear system model for repetitious simulation with input sequences. The predicted flow outputs are obtained with the simpler model at significant savings of money and time. The procedures for constructing a complex kinematic model of a 40 acre (161,880 m²) reference watershed and deriving the simpler system model are outlined. The results of predictions from both models are compared with a selected set of measured events, all having essentially the same initial conditions. Peak discharges ranged from 3 to 118 ft³/sec (0.085 to 3.34 m³/sec), which includes the largest event of record. The inherent limitations of lumped systems models are demonstrated, including the bias caused by their inability to model infiltration losses after rainfall ceases. Computer costs and times for the models were compared. The derived simple model has a cost advantage when repeated use of a model is required. Such an applications hydrologic model has an engineering tradeoff of reduced accuracy, and lumping bias, but is more economical for certain design purposes.     

Urban ecological systems: scientific foundations and a decade of progress

Urban ecological studies, including focus on cities, suburbs, and exurbs, while having deep roots in the early to mid 20th century, have burgeoned in the last several decades. We use the state factor approach to highlight the role of important aspects of climate, substrate, organisms, relief, and time in differentiating urban from non-urban areas, and for determining heterogeneity within spatially extensive metropolitan areas. In addition to reviewing key findings relevant to each state factor, we note the emergence of tentative "urban syndromes" concerning soils, streams, wildlife and plants, and homogenization of certain ecosystem functions, such as soil organic carbon dynamics. We note the utility of the ecosystem approach, the human ecosystem framework, and watersheds as integrative tools to tie information about multiple state factors together. The organismal component of urban complexes includes the social organization of the human population, and we review key modes by which human populations within urban areas are differentiated, and how such differentiation affects environmentally relevant actions. Emerging syntheses in land change science and ecological urban design are also summarized. The multifaceted frameworks and the growing urban knowledge base do however identify some pressing research needs.     

Neighbourhood characteristics and urban gardens in the Toledo metropolitan area: staffing and voluntarism,food production,infrastructure, and sustainability practices

Urban gardens are important sources of sustenance for communities with limited access to food. Hence, this study focuses on food production in gardens in the Toledo metropolitan area in Northwest Ohio. We administered surveys to 150 garden managers from November 2014 to February 2015 in our attempt to better understand how neighbourhood racial composition and poverty levels are related to staffing and voluntarism, food production and distribution, the development of infrastructure, and the adoption of sustainability practices in urban gardens. The results from 30 gardens are presented in this paper. We used Geographic Information Systems to map the gardens and overlay the map with 2010 census data so that we could conduct demographic analyses of the neighbourhoods in which the gardens were located. Though the gardens were small – two acres or less – up to 46 varieties of food were grown in a single garden. Gardens also operated on small budgets. Food from the gardens was gifted or shared with friends, family, and neighbourhood residents. Gardens in predominantly minority neighbourhoods tended to have fewer institutional partners, less garden infrastructure, and had adopted fewer sustainable practices than gardens in predominantly White neighbourhoods. Nonetheless, residents of predominantly minority and high-poverty neighbourhoods participated in garden activities and influenced garden operations. Volunteering and staffing were racialised and gendered.     

Using Paleo Reconstructions to Improve Streamflow Forecast Lead Time in the Western United States

In water stressed regions, water managers are exploring new horizons that would help in long‐range streamflow forecasts. Oceanic‐atmospheric oscillations have been shown to influence streamflow variability. In this study, long‐lead time streamflow forecasts are made using a multiclass kernel‐based data‐driven support vector machine (SVM) model. The extended streamflow records based on tree ring reconstructions were used to provide a longer time series data. Reconstructed data were used from 1658 to 1952 and the instrumental record was used from 1953 to 2007. Reconstructions for oceanic‐atmospheric oscillations included the El Niño‐Southern Oscillation, Pacific Decadal Oscillation, Atlantic Multidecadal Oscillation, and North Atlantic Oscillation. Streamflow forecasts using all four oscillations were made with one‐year to five‐year lead times for 21 gages in the western United States. This is the first study that uses both instrumental and reconstructed data of oscillations in SVM model to improve streamflow forecast lead time. SVM model was able to provide “satisfactory” to “very good” forecasts with one‐ to five‐year lead time for the selected gages. The use of all the oscillation indices helped in achieving better predictability compared to using individual oscillations. The SVM modeling results are better when compared with multiple linear regression model forecasts. The findings are statistical in nature and are expected to be useful for long‐term water resources planning and management.     

Predicting deer-vehicle collisions in an urban area

Collisions with deer and other large animals are increasing, and the resulting economic costs and risks to public safety have made mitigation measures a priority for both city and wildlife managers. We created landscape models to describe and predict deer-vehicle collision (DVCs) within the City of Edmonton, Alberta. Models based on roadside characteristics revealed that DVCs occurred frequently where roadside vegetation was both denser and more diverse, and that DVCs were more likely to occur when the groomed width of roadside right-of-ways was smaller. No DVCs occurred where the width of the vegetation-free or manicured roadside buffer was greater than 40 m. Landscape-based models showed that DVCs were more likely in more heterogeneous landscapes where road densities were lower and speed limits were higher, and where non-forested vegetation such as farmland was in closer proximity to larger tracts of forest. These models can help wildlife and transportation managers to identify locations of high collision frequency for mitigation. Modifying certain landscape and roadside habitats can be an effective way to reduce deer-vehicle collisions.     

MANGANESE CYCLE IN IMPOUNDMENT WATER

Manganese entering impounded water will undergo a cyclic transformation. Oxidation precipitates manganese from top waters. At the bottom of the lake, biological activity will render manganese soluble by both intracellular as well as extracellular activity. The study was made to demonstrate that biological reduction and transformation, organometallic complexation, together with the presence of carbon dioxide and the lowering of pH all have some effect on the solubility of manganese. Dissolved manganese may be brought back to top waters during the lake overturn and therefore deteriorates the water quality.     

Biodiversity and biotechnology

The maintenance of biodiversity is urged from many quarters and on grounds ranging from aesthetic considerations to its usefulness, particularly for biotechnology. But regardless of the grounds for preserving biodiversity, writers are generally in agreement that it should be preserved. But, in examining the various references biodiversity, such as species diversity, genetic diversity, and habitat diversity, it is apparent that we cannot aim to preserve biodiversityas such, since there are a number of conflicts in any such undertaking. In preserving one aspect of biodiversity, we damage another aspect. Five arguments which attempt to ground our moral concern for biodiversity are reviewed and critiqued, not only for their consistency but also for their power to move us to action. The final section of the paper shows how conflicts in the values of personal and environmental health can impair ethical action and especially policy formation.An earlier version of this paper was read at the conference on Agriculture, Food, and Human Values: Tradition and Change, Orlando, Florida, October 7–9, 1987.     

Surface applied water treatment residuals affect bioavailable phosphorus losses in Florida sands

Water treatment residuals (WTR) can reduce runoff P loss and surface co-application of P-sources and WTR is a practical way of land applying the residuals. In a rainfall simulation study, we evaluated the effects of surface co-applied P-sources and an Al-WTR on runoff and leacheate bioavailable P (BAP) losses from a Florida sand. Four P-sources, namely poultry manure, Boca Raton biosolids (high water-soluble P), Pompano biosolids (moderate water-soluble P), and triple super phosphate (TSP) were surface applied at 56 and 224kgPha(-1) (by weight) to represent low and high soil P loads typical of P- and N-based amendments rates. The treatments further received surface applied WTR at 0 or 10gWTRkg(-1) soil. BAP loss masses were greater in leachate (16.4-536mg) than in runoff (0.91-46mg), but were reduced in runoff and leachate by surface applied WTR. Masses of total BAP lost in the presence of surface applied WTR were less than approximately 75% of BAP losses in the absence of WTR. Total BAP losses from each of the organic sources applied at N-based rates were not greater than P loss from TSP applied at a P-based rate. The BAP loss at the N-based rate of moderate water-soluble P-source (Pompano biosolids) was not greater than BAP losses at the P-based rates of other organic sources tested. The hazards of excess P from applying organic P-sources at N-based rates are not greater than observed at P-based rates of mineral fertilizer. Results suggest that management of the environmental P hazards associated with N-based rates of organic materials in Florida sands is possible by either applying P-sources with WTR or using a moderate water-soluble P-source.     

Sources and Transport of Phosphorus to Rivers in California and Adjacent States,U.S., as Determined by SPARROW Modeling

The SPARROW (SPAtially Referenced Regression on Watershed attributes) model was used to simulate annual phosphorus loads and concentrations in unmonitored stream reaches in California, U.S., and portions of Nevada and Oregon. The model was calibrated using de‐trended streamflow and phosphorus concentration data at 80 locations. The model explained 91% of the variability in loads and 51% of the variability in yields for a base year of 2002. Point sources, geological background, and cultivated land were significant sources. Variables used to explain delivery of phosphorus from land to water were precipitation and soil clay content. Aquatic loss of phosphorus was significant in streams of all sizes, with the greatest decay predicted in small‐ and intermediate‐sized streams. Geological sources, including volcanic rocks and shales, were the principal control on concentrations and loads in many regions. Some localized formations such as the Monterey shale of southern California are important sources of phosphorus and may contribute to elevated stream concentrations. Many of the larger point source facilities were located in downstream areas, near the ocean, and do not affect inland streams except for a few locations. Large areas of cultivated land result in phosphorus load increases, but do not necessarily increase the loads above those of geological background in some cases because of local hydrology, which limits the potential of phosphorus transport from land to streams.