首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Strategies to predict, and thus limit, potentially detrimental environmental impacts of abyssal disposal of wastes are severely limited by our lack of knowledge of deep-sea processes and lack of opportunity to directly study waste disposal in abyssal environments. Probable successional sequences following burial of benthic faunas by sewage sludge and dredged material on the abyssal seafloor are drawn by analogy with well-known processes in shallow-marine water. Scales of change and recovery of abyssal benthic faunas from episodic deposition of waste material are examined by extrapolation from what is currently known about turbidite sedimentary provinces, in particular, the Venezuela Abyssal Plain and the Great Meteor East area of the Madeira Abyssal Plain. Results suggest that initial benthic faunal recolonization would take place within years following episodic depositions of waste on the abyssal seafloor. Anoxic conditions or chemical inhibitory effects may delay initial benthic recolonization for hundreds of years. Establishment of equilibrium benthic faunal assemblages probably takes hundreds to potentially thousands of years. Potentially detrimental effects dictate that the surface areas of individual waste deposits should be minimized and the deposits should be isolated by capping with nontoxic materials or chemical barriers.  相似文献   

2.
The Naval Research Laboratory (NRL), with industry and university participation, conducted an assessment of the concept of isolating certain wastes (i.e., sewage sludge, fly ash from municipal incinerators, and contaminated dredged material) on the oceans' abyssal seafloor. In this assessment the advantages, disadvantages, and economic and environmental viability of potential engineering methods for achieving abyssal waste isolation were identified and compared. This paper presents background to the Abyssal Plains Waste Isolation (APWI) Project, describes the characteristics of the waste streams and quantities potentially available for disposal via the abyssal isolation concept, summarizes regulations affecting use of the abyssal seafloor for disposal of wastes, and introduces the technical and scientific premises underlying implementation of the concept.  相似文献   

3.
高谦  商蕾  管聪 《中国修船》2021,(1):39-43
针对配备有余热回收系统的船舶中,现有电力系统配置方案存在低电力负荷时发电机组功率过剩,运行效率较低的问题,文章提出了基于年均成本的船舶电力系统配置优化方法,建立了配置优化的数学模型,并根据模型给出了配置优化方案。配置优化方案同原始配置方案的对比,结果表明,配置优化方案可以有效降低电力系统的年均成本,提高系统内设备的运行效率。  相似文献   

4.
Identification of optimal sites for the isolation of waste on the abyssal seafloor was performed with two approaches: by the traditional method of map overlays of relevant attributes, and by a specially developed, automated Site-Selection Model (SSM). Five initial, Surrogate Sites, identified with the map-overlay approach, were then compared with the more rigorously produced scores from the SSM. The SSM, a process for optimization of site locations, accepts subjective, expert-based judgments and transforms them into a quantitative, reproducible, and documented product. The SSM is adaptable to any siting scenario. Forty-one factors relevant to the isolation scenario, including 21 weightable factors having a total of 123 scorable categories, have been entered into the SSM. Factors are grouped under project definition, unique environments, anthropogenic, geologic, biologic, weather, oceanographic and distance criteria. The factor scores are linked to a georeferenced database array of all factors, corresponding to 1°×1° latitude–longitude squares. The SSM includes a total of 2241 one-degree squares within 1000 n.m. of the U.S. coasts, including the western North Atlantic, the Gulf of Mexico, and the eastern North Pacific. Under a carefully weighted and scored scenario of isolation, the most favorable sites identified with the SSM are on the Hatteras and Nares Abyssal Plains in the Atlantic. High-scoring sites are also located in the Pacific abyssal hills province between the Murray and Molokai Fracture Zones. Acceptable 1° squares in the Gulf of Mexico are few and of lower quality, with the optimum location on the northern Sigsbee Abyssal Plain. Two of the five Surrogate Site locations, on the Hatteras and Sigsbee Abyssal Plains, correspond to the best SSM sites in each ocean area. Two Pacific and a second Atlantic Surrogate Site are located in low-scoring regions or excluded by the SSM. Site-selection results from the SSM, although robust, are an initial attempt to quantify the site-selection process. The SSM database exposes a significant lack of high-quality information for many areally mappable attributes on the abyssal seafloor, particularly bottom-current speed and measures of biologic productivity and flux. Terminologies and classifications of some measures, such as sediment types, suffer from parochialism and vary by ocean. Considerable research is needed even for a broad understanding of the environmental measures required to make sound societal decisions about use of the abyssal seafloor for disposal or other purposes.  相似文献   

5.
序批式活性污泥法,即SBR法,随着其反应器控制系统的完善越来越受到人们的重视。通过实验研究了解该反应器的特性。实验分驯化污泥、增加负荷、确定运行周期等3个阶段。首先通过驯化污泥明确化学品船洗舱污水的可生化降解性;增强负荷是为了解装置的处理能力;而确定运行周期是针对该污水寻找一合适的处理周期。本实验结论如下:1)使用SBR法处理化学品船洗舱污水切实可行;2)实验中出现污水膨胀现象可采取措施控制;3)使用该装置产生的污泥量少,处理费用低。  相似文献   

6.
海洋石油平台余热利用研究   总被引:2,自引:2,他引:0  
杨树 《船舶工程》2015,37(5):94-96
东海某DPP平台投产近十五年后,出现设备老化、工艺系统处理量发生变化等情况,从而透平电站、热油锅炉和工艺处理系统出现余热,如何减少能源浪费,及时有效回收利用,需要及时解决问题。通过对基础资料分析研究、平台生产实地调研,提出余热利用方案,并进行成本投资/回报比较,最终验证了方案的正确性。  相似文献   

7.
The response of pore water oxygen, nitrate, sulfate, sulfide, ammonium and methane and particulate organic carbon distributions to the input of 8.5 million m3 (3.8×1012 g) of organic-rich waste materials is simulated. The deposit is assumed to be conical with a maximum thickness of approximately 20 m. Remineralization reactions within the deposit rapidly deplete any initially available pore water oxidants such as oxygen, nitrate and sulfate, and are subsequently dominated by fermentation reactions. Diffusion downward of reduced metabolites, sulfide, ammonium and methane, depletes the available oxidants in the pore waters below the waste pile, increasing the thickness of the anoxic layer. While the impacted region is limited to essentially the deposition site, recovery of the pore waters is estimated to be >104 years. The overall computational results are corroborated by the pore water distributions observed at turbidite boundaries. Numerous uncertainties in the parameterizations limit the overall accuracy of the calculations presented. The most significant of these are: (1) A quantitatively accurate assessment of the remineralization rate of the deposited organic matter including its rate of inoculation by abyssal microorganisms; (2) a detailed assessment of potential non-diffusive pore water transport processes including advection due to compaction and buoyancy-driven flows and enhanced exchange due to macrobenthic irrigation activities and (3) an assessment of the potential alteration of pore space and methane reactivity due to gas hydrate formation.  相似文献   

8.
林贵华  徐礼康 《船舶工程》2020,42(S1):266-270
针对豪华邮轮在每次航行中每餐都会产生大量的餐厨垃圾,设计一款餐厨垃圾处理系统。该系统研究了一种新型的斜齿圆柱齿轮磨辊粉碎方式和微波干燥脱水方式相结合而成的餐厨垃圾粉碎脱水一体机,并对脱水后的处理工艺压缩储存进行研究。应用CATIA软件对邮轮用餐厨垃圾粉碎脱水一体机和压缩装置进行三维建模并基于Workbench软件对粉碎装置的齿轮磨辊进行接触分析和自由模态分析,验证此设计的可行性。  相似文献   

9.
Recent Thredbo Conferences have begun to explore the importance of the relationship between public transport service purchaser and provider in the development of successful public transport services. However, practical examples to test the trusting partnership model are rare. Bus service planning and delivery in Melbourne, Australia, has pioneered the trusting partnership approach, from agreement about desirable service standards and requisite operator qualifications (at the Tactical level) to detailed service delivery contracts. New negotiated performance-based metropolitan bus contracts commenced in January 2009, embodying principles discussed in previous Thredbo Conferences. This paper reports on the Tactical planning process that agreed service standards and the subsequent contract negotiation process, reflecting a trusting partnership between purchaser and provider, while remaining transparent and accountable and maintaining performance pressure on the provider. It shows how patronage growth rates have increased dramatically and identifies areas where further enhancements should be explored in the contracting area.  相似文献   

10.
有机朗肯循环发电装置能够有效地利用工业中的废热,将其转化成清洁能源—电能。本文介绍了朗肯循环发电理论方案、基本工作原理、系统计算方法。并且在理论的基础上,对某陶粒砂厂烟气工况进行了分析、计算,这对低品味工业余热的开发利用具有重要的参考价值。  相似文献   

11.
With winds of change from the European Commission reaching the Netherlands, the national government altered the Law on Passenger Transport in 2000 to best reflect European demands. This new law meant competitive tendering became obligatory. At first, the metropolitan transport authorities in the three largest cities (Amsterdam, The Hague, and Rotterdam) were granted an extended deadline for tendering. However, due to shifting winds from Brussels, in 2007 the Dutch national government dropped the obligation to tender for the three cities. Suddenly the authorities had to decide for themselves whether or not to tender. This article describes the different routes and outcomes of the three metropolitan authorities. Where the metropolitan authority in Rotterdam aimed at conservation of their existing model, the authorities of Amsterdam and The Hague embraced change. In The Hague conformation to the letter of the law seemed an important driver, whereas confrontation between different interests in the region was the starting point for change in Amsterdam.  相似文献   

12.
刘扬 《中国修船》2011,24(3):31-33
舰船在运行、修理过程中会产生大量的废水。对废水处理技术应用进行研究,对实现废水安全处理并有效降低处理和处置费用、降低环境危害具有实际意义。文章就废水产生的种类、来源、危害和处理方法进行了系统的研究和论述,对应用的处理方法、系统工艺流程进行了效能分析并提出了应对措施。  相似文献   

13.
The burgeoning commitment to contracting the delivery of bus services through competitive tendering or negotiated performance-based contracts has been accompanied by as many contract payments schemes as there are contracts. We are now well placed to design a simplified performance-linked payment (SPLP) model that can be used as a reference point to ensure value for money, given the accumulation of experiences throughout the world which have revealed substantive common elements in contracts. Whether the payment to the operator is framed as a payment per passenger or as a payment per service kilometre, the SPLP identifies efficient subsidy outcomes that are linked to a proxy indicator of net social benefit per dollar of subsidy. We illustrate how the SPLP model can be applied to obtain the gross (subsidy) cost per passenger (or per passenger km) from measures of gross cost efficiency and network effectiveness. This model can then be used as part of a benchmarking activity to identify reference value of money prospects in respect of passengers per $ subsidy outlay by adjusting for influences not under the control of the service provider. A single framework to identify contract payments to operators, and to assess (i.e., benchmark) operator performance on critical KPIs, is provided by internalising critical key performance indicators (KPIs) in the design of the SPLP. The proposed SPLP model is sufficiently general to be independent of the procurement method (competitive tendered or negotiated, for example) and of the treatment of revenue allocation (net or gross based contracts), with the additional advantage of being able to assess value for money for government.  相似文献   

14.
船舶余热梯级利用的淡水-空调复合供能系统   总被引:1,自引:0,他引:1  
曹石  杨征  安卫超 《船舶工程》2017,39(5):76-80
探讨船舶柴油机余热利用的发展潜力和当前研究现状,在此基础上根据能量梯级回收利用原则,设计一种以水/水蒸汽为单一热媒的新型淡水-空调复合供能系统,该系统包括冷却水余热回收和废气余热回收2个模块,兼具供热/制冷、制取淡水、生活用水等诸多作用。最后,对该系统进行热平衡分析,结果表明该系统可实现68.4%的余热回收量,低碳环保,节能效益显著。  相似文献   

15.
大型水利水电开发建设项目施工期具有占地大、施工作业面积广、土石方开挖量大的特点,建设过程中不可避免对生态造成影响,如何减少施工期弃渣带来的生态环境的不利影响成为一种挑战。为此,以岷江龙溪口航道枢纽工程施工期采取的生态保护措施为例,研究表明:在施工期优化施工工艺、施工区布置、施工工序等可有效减少弃渣产生量。在此基础上,提出了弃渣减量和弃渣资源化利用途径,可为国内其他规划和航电枢纽在建项目的生态措施提供借鉴。  相似文献   

16.
ABSTRACT

This study empirically evaluated the effects of unmanned aerial vehicles (UAVs) applications and acceptable cost on intention to use UAVs in maritime shipping contexts. Factor analysis was employed to identify key UAVs applications (i.e. pollution forensics, supervision and service, search and rescue, humanitarian and emergency delivery, and safety and security), acceptable UAV cost, and intention to use UAVs. Survey data were collected from 201 respondents working for a maritime port corporation, shipping company, agency, and stevedoring company, and then hierarchical regression analysis was conducted to test research hypotheses and examine the effects of UAVs applications and acceptable cost dimensions on intention to use UAVs. The results suggested that the pollution forensics, supervision and service, search and rescue, humanitarian and emergency delivery, and safety and security dimensions positively affected intention to use UAVs. The study findings also revealed negative associations among seniority, turnover, and intention to use UAVs. Theoretical contributions and managerial implications are proposed to assist maritime port bureaus, corporations, and operating practice design in remaining competitive and efficient.  相似文献   

17.
杨光海  郑超瑜  陈武 《船海工程》2012,41(5):115-118
探讨转轮除湿空调系统在船舶上应用的可行性。在分析干燥剂再生温度和除湿效果的基础上,根据船舶余热的品质和船舶空调的特点,构建了一个船用除湿空调系统。该系统采用单个转轮两级除湿的方案,利用船舶余热作为干燥剂的再生热源,采用海水冷却和压缩式制冷机组冷却相结合的冷却方式,以保证送风温度的稳定。根据所确定的系统方案,建立起船用单个转轮两级除湿空调系统的实验台,用于研究模拟海洋环境下该系统的性能。  相似文献   

18.
孙未 《船舶》2020,(2):52-57
鉴于普通柴油机能量有效转化率不足50%,以及船东对节能减排的特殊要求,文章以缸套水为研究对象,设计出一套能够回收主、辅机缸套水废热的加热系统。利用主、辅机产生的废热去加热燃油舱、污油舱、货油洗舱水以及空调等用户,以实现节能、提高燃油利用率的目的。满足船舶在停泊、装卸货、进出港、正常航行等工况时以及洗舱时的热能需要。运用简单实用的办法提高船舶动力装置总效率,为中小型船舶的废热利用提供借鉴。  相似文献   

19.
林红良  李志  祝广场 《船电技术》2012,(Z1):35-37,41
在余热发电系统中,换热器直接将热源中的热量吸收传递到系统中,然后将从透平中出来的工质冷凝,其性能好坏直接影响了整个系统的效率。本文引入了无量纲熵产数Ns表示换热器的热力完善程度,并且通过熵产分析,揭示了换热器能耗产生的原因,确定了最佳的热力参数匹配,能够更好的完成节能目的。对于工业中余热发电项目的优化具有重要参考意义。  相似文献   

20.
论中国造船企业的核心竞争力   总被引:9,自引:1,他引:8  
陈强 《中国造船》2004,45(1):1-7
本文分析了中国造船企业的竞争优势与劣势,并提出了培育中国造船企业核心竞争力的基本战略.中国造船企业的竞争优势主要在于生产要素、需求条件及政府支持等方面;劣势在于相关产业、企业目标、战略、组织结构等方面.培育中国造船企业核心竞争力必须采取模仿性提高、差异化、低成本、聚焦重点客户、提升集成设计能力、采用先进造船模式、提升生产系统的管理能力、建立优秀企业文化、创新、信息化及战略性人力资源管理等战略.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号