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1.
文中提出了用先堆焊镍基合金后自蔓延(SHS)内衬陶瓷,最后将两管道的堆焊端进行焊接的方法来提高石油天然气管道的抗腐蚀、冲蚀能力;并在制好的堆焊/自蔓延管道上截取试样,进行了X射线衍射试验、硬度试验和冲蚀磨损试验,为更耐久的石油天然气管道的制作提供了工艺方法,也为管道性能分析提供了试验数据。  相似文献   

2.
通过对浙江省高速公路30对服务区污水处理方案的调查,及对沪杭甬和杭金衢高速部分服务区污水取样研究,针对污水氨氮浓度高的特点,采用兼氧-好氧-物化的组合工艺来处理这类污水,研究结果表明,污水的各项指标均能达到国家一级排放标准。经核算,该工艺每吨水的处理成本约为0.58元,经济和环境效益十分显著。  相似文献   

3.
本文就广贺高速公路江坪高架桥3号墩4号桩因桩基承载力达不到设计要求,采用切割旋喷法进行处理的工艺,旨在同类工程质量缺陷处理借鉴。  相似文献   

4.
天然气管道的干燥处理是输气管道投产前的重要工艺环节.研究表明,最经济安全的干燥法为干空气干燥法,其过程为复杂的传热、传质.文中介绍干空气干燥工艺原理,并对其干燥和吸水过程,应用质量守恒原理、相平衡理论和费克定律,建立了天然气管道干燥机理模型、吸水机理模型及密闭稳定再干燥模型,编制了应用程序;利用双庙1井-杨柳垭天然气管...  相似文献   

5.
《综合运输》2010,(1):93-93
2009年12月14日,中国-中亚天然气管道通气仪式在土库曼斯坦阿姆河右岸巴哥德雷合同区第一天然气处理厂举行。中国国家主席胡锦涛同土库曼斯坦、哈萨克斯坦、乌兹别克斯坦三国总统共同出席通气仪式。中国-中亚天然气管道起始于土库曼斯坦-乌兹别克斯坦边境,经乌兹别克斯坦、哈萨克斯坦到达中国霍尔果斯。管道分AB双线敷设,单线长1833公里,A线于今年12月初试运投产。  相似文献   

6.
旋挖硬切割法咬合支护桩工艺有利于施工质量控制和保障安全,且各桩间止水效果良好,能为主体结构创造一个良好的施工作业环境。文章结合工程实例,介绍了旋挖硬切割法咬合支护桩施工工艺,分析了施工中存在的问题与对策,为类似工艺施工提供参考。  相似文献   

7.
以唐山LNG外输管道工程丰南分输站工艺管道的吹扫试压方法取得的效果为依据,总结了在天然气站场工艺管道吹扫试压方法选取中需考虑的因素。从吹扫介质选取、吹扫段落的划分、吹扫注意事项等方面对吹扫方法进行了分析;从试压方法选取、试压段落的划分、试压注意事项等方面对试压方法进行了分析。最后结合国内天然气站场的实际情况,对天然气站场工艺管道吹扫试压方法的制定提出了建议。  相似文献   

8.
天然气脱硫工艺的研究与发展   总被引:3,自引:0,他引:3  
文中介绍了几种常用的脱硫工艺,如醇胺法、Sulfatreat法、低温甲醇洗技术等,指出各方法的优势及目前存在的问题,提出了今后天然气脱硫工艺发展的趋势。认为应在成熟的天然气脱硫方法的基础上进一步改进,实现高效节能。指出膜吸收是膜基气体分离与传统的物理吸附、化学吸收、低温精馏、深冷结合起来的新型分离技术。与常规工艺相比具有明显的优势,是今后天然气脱硫技术研究发展的新方向。  相似文献   

9.
杭甬线天然气管道自投产以来尚未进行过清管,随着年输气量逐年增加,从管道运行状况来看有必要对其进行清管作业,清除管道内长期积存的杂质,检测管道内部通过能力以及自身缺陷。合理的输气方案和有效的控制清管器速度的措施保障了此次清管作业顺利实施。文中详细介绍了杭甬线东段(春晓-余姚)天然气管道清管作业的工艺方案及过程,结合自身运行特点和国内外长输管道清管作业经验,总结清管作业中存在的问题,提出改进措施和建议,为天然气管道安全高效的清管作业提供参考。  相似文献   

10.
用涂装法取代地下管道氧煤沥青一嵌二布三胶工艺,以缩短工序并达到更为出色的防腐性为目的。  相似文献   

11.
为提高天然气气源供应的稳定性、可靠性,拓展气源采购范围,降低采购成本,国内各大型管网在资源供应上采取了多个气源方,以多点、多方位对同一管网供气,从而构成了天然气管网的多气源供应格局.因天然气产地及生产工艺的原因,各气源间的组成和物性参数存在差异,如何确保多种气源在同一管网中进行稳定、安全输送,是国内外亟待解决的技术难题...  相似文献   

12.
针对长输油气管道施工和抢维修过程中,施工现场“碰死口”下短管工序对钢管切割和管端坡口的需求,研制一套机械分瓣式钢管切割机设备.该切割机使用安全的冷切割工艺,钢管母材的性能不会改变.采用分瓣式联接结构,通过夹持机构将两瓣固定在钢管外壁上,通过刀盘的旋转和刀具的自动进给,能够同时实现钢管的切割及管端坡口的功能.现场实验情况...  相似文献   

13.
在山区高速铁路建设中,不可避免地会出现深路堑,如果方案选择不合理,则会造成当地环境的破坏,导致地质灾害频发,直接威胁到高铁运营的安全.因此,正确、合理地选用深路堑和隧道方案,显得非常重要.文章主要从地质条件、环境影响、施工难度、综合经济成本、运营安全等五个方面,比较研究了深路堑与隧道选用的适用性,并提出了方案选择的建议.  相似文献   

14.
Plug-in hybrid electric vehicles (PHEVs) can provide many of the benefits of battery electric vehicles (BEVs), such as reduced petroleum consumption and greenhouse gas emissions, without the “range anxiety” that can accompany driving a vehicle with limited range when there are few charging opportunities. However, evidence indicates that PHEVs are often plugged in more frequently than BEVs in practice. This is somewhat paradoxical: drivers for whom plugging in is optional tend to do so more frequently than those for whom it is necessary. This has led to the coining of a new term – “gas anxiety” – to describe the apparent desire of PHEV drivers to avoid using gasoline. In this paper, we analyze the variables influencing the charging choices of PHEV owners, testing whether drivers express preferences consistent with the concept of gas anxiety. We analyze data collected in a web-based stated preference survey using a latent class logit model. The results reveal two classes of decision-making patterns among the survey respondents: (1) those who weight the cost of gasoline and the cost of recharging approximately equally (the cost-minimizing class), and (2) those who weight the cost gasoline more heavily than the cost of recharging (the gas anxiety class). Respondents in the gas anxiety class expressed a willingness to recharge at a charging station even when doing so would cost approximately four times as much as the cost of the gasoline avoided. While the gas anxiety class represents the majority of our sample, more recent PHEV adopters are more likely to be in the cost-minimizing class. Looking forward, this suggests that public charging station operators may need to price charging competitively with gasoline on a per-mile basis to attract PHEV owners.  相似文献   

15.
There have been ongoing debates over whether battery electric vehicles contribute to reducing greenhouse gas emissions in China’s context, and if yes, whether the greenhouse gas emissions reduction compensates the cost increment. This study informs such debate by examining the life-cycle cost and greenhouse gas emissions of conventional vehicles, hybrid electric vehicles and battery electric vehicles, and comparing their cost-effectiveness for reducing greenhouse gas emissions. The results indicate that under a wide range of vehicle and driving configurations (range capacity, vehicle use intensity, etc.), battery electric vehicles contribute to reducing greenhouse gas emissions compared with conventional vehicles, although their current cost-effectiveness is not comparable with hybrid electric vehicles. Driven by grid mix optimization, power generation efficiency improvement, and battery cost reduction, the cost-effectiveness of battery electric vehicles is expected to improve significantly over the coming decade and surpass hybrid electric vehicles. However, considerable uncertainty exists due to the potential impacts from factors such as gasoline price. Based on the analysis, it is recommended that the deployment of battery electric vehicles should be prioritized in intensively-used fleets such as taxis to realize high cost-effectiveness. Technology improvements both in terms of power generation and vehicle electrification are essential in improving the cost-effectiveness of battery electric vehicles.  相似文献   

16.
The paper challenges the conventional view that the movement of goods through supply chains must continue to accelerate. The compression of freight transit times has been one of the most enduring logistics trends but may not be compatible with governmental climate change policies to cut greenhouse gas emissions by 60–80% by 2050. Opportunities for cutting CO2 emissions by ‘despeeding' are explored within a freight decarbonisation framework and split into three categories: direct, indirect and consequential. Discussion of the direct carbon savings focuses on the trucking and deep-sea container sectors, where there is clear evidence that slower operation cuts cost, energy and emissions and can be accommodated within current supply chain requirements. Indirect emission reductions could accrue from more localised sourcing and a relaxation of just-in-time (JIT) replenishment. Acceleration of logistical activities other than transport could offset increases in freight transit times, allowing the overall carbon intensity of supply chains to reduce with minimal loss of performance. Consequential deceleration results from other decarbonisation initiatives such as freight modal split and a shift to lower carbon fuels. Having reviewed evidence drawn from a broad range of sources, the paper concludes that freight deceleration is a promising decarbonisation option, but raises a number of important issues that will require new empirical research.  相似文献   

17.
输气管线摩阻系数的影响因素以及减阻的主要方法   总被引:1,自引:0,他引:1  
在输气管线中 ,摩擦阻力的存在对输气管线运行产生了很大影响。一方面 ,摩擦阻力越大 ,管线压力降低越快 ,动力损耗越多 ;另一方面 ,摩擦阻力影响输气流量 ,摩擦阻力越大 ,流量越小 ,会增加管线的运营成本。因而 ,要提高长距离输气管线的输气流量、降低运营成本 ,降低摩阻系数是非常必要的。考察了大量的摩阻计算公式 ,求解出各种不同条件下的摩阻系数 ,分析和讨论了影响摩阻系数的因素 ,提出了降低摩阻系数的主要方法 ,重点介绍了加内壁涂层的减阻方法。计算分析表明 :管道施加内壁涂层之后 ,可大大降低摩阻系数  相似文献   

18.
In this study, the costs involved in the use of petrol, diesel, natural gas, biogas, and methanol (produced from natural gas and biomass) in cars and heavy trucks are compared. The cost includes fuel cost, extra capital cost for vehicles using alternative fuels, and the environmental cost of VOC, NOx, particulate and CO2 emission based on actual 1996 and estimated 2015 emission factors. The costs have been calculated separately for rural, urban and city-centre traffic. A complete macroeconomic assessment of the effect of introducing alternative fuels is not, however, included in the study. The study shows that no alternative fuel can compete with petrol and diesel in rural traffic when the economic valuation of CO2 emission is taken as current Swedish CO2 taxes ($200/tonne C). In cities with a natural gas network, natural gas is the fuel with the lowest cost for both cars and heavy trucks, based on 1996 emission factors. Methanol from natural gas and biogas from waste products can also compete with diesel in urban traffic. With predicted improvements in technology and subsequent emission reductions, no alternative fuel can compete with petrol in any of the traffic situations studied by 2015, and only in city-centre traffic will alternative fuels be less costly than diesel in heavy vehicles. Of the biomass-based fuels studied, low-cost biogas from waste products is the most competitive one and is, already at current CO2 taxes, the fuel with lowest cost for heavy trucks in urban traffic in areas where natural gas networks do not exist. To enable the more widespread use of biomass-based fuels, i.e. using feedstocks such as energy crops or logging residues that are available in larger amounts, the economic valuation of CO2 emission has to be 2–2.5 times higher than current Swedish CO2 tax level.  相似文献   

19.
TBM滚刀刀圈磨损机理研究   总被引:2,自引:0,他引:2  
滚刀刀圈的磨损影响施工成本、设备利用率和掘进效率,刀圈的快速磨损与工程地质条件密切相关,是一项重要的工程地质问题.基于摩擦磨损学的原理,结合滚刀破岩机理,分析了在滚刀破岩过程中刀圈的磨损机理.应用滚刀的磨损机理,解释了滚刀刀圈的三种磨损形式,分析得出影响刀圈磨损的两大因素,即机械因素和地质因素,并提出建立刀圈消耗量预测模型应该考虑这两方面的因素.  相似文献   

20.
水平旋喷桩施工工艺在深圳地铁施工中的应用   总被引:1,自引:0,他引:1  
郭伟 《现代隧道技术》2012,49(2):114-118,141
在深圳地铁安托山站—侨香站区间矿山法隧道超前支护施工中,由于采用了水平旋喷桩施工工艺,成功地解决了安-侨区间暗挖隧道在饱和粉细砂层及砾砂层中近距离穿越大断面雨水箱涵及φ500 mm次高压燃气管线的难题,节约了施工成本,充分显示了水平旋喷桩施工工艺在富水砂层浅埋暗挖隧道开挖预支护工程应用上的经济优势。文章论述了水平旋喷桩的工艺机理、适应性、优缺点以及在该工程中的应用效果。  相似文献   

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