LNG加气站BOG放散原因分析及降低措施

针对未连接城市燃气管网的LNG加气站,调研BOG放散量与储罐充装间隔期的关系,发现对于未做特殊保冷的普通LNG加气站,当储罐充装间隔期在4 d及以内时,基本不发生BOG放散。当储罐充装间隔期超过4 d时,BOG放散量随着充装间隔期的增加而增大。结合实际运行中的LNG储罐压力的变化,分析BOG放散量与LNG充装间隔期的关系。针对日销气量少、充装间隔期长的LNG加气站,提出对LNG加气站进行分卸以控制充装间隔期在4 d及以内,建立判断分卸是否经济的数学模型。     

关于L-CNG、LNG加气站储罐BOG自动排放系统应用的研究

LNG储罐BOG自动排放系统应用非常普及,它选用自力式压力释放阀来实现储罐BOG自动排放。但在加气站的LNG储罐一般没有设计BOG自动排放系统,主要原因是采用这种自力式压力释放阀来实现BOG自动排放有一定的缺点,不便于准确、频繁地调整压力参数。本文研究利用PLC站控系统控制气动阀,对储罐BOG进行自动排放,以获得最佳的工艺参数,取得良好的效果,并在新建加气站中推广应用。     

信息与其他

深圳市大工业区天然气供应站工程内容:由液化天然气(LNG)槽车或集装箱罐车将液化天然气运至LNG供应站,在卸气台通过自带的增压器或站区增压器对槽车储罐增压,利用压差将LNG送至低温LNG储罐储存,储罐储存期间压力保持在0 .3MPa ,储存温度为- 14 5℃。使用时,打开储罐的自增压系统,通过储罐增压器增压至0 .5MPa ,然后通过储罐自身的压力进入空温式气化器气化,气化后的气态天然气通过调压、计量、加臭后送入管网供工业用户。目前该工程为工业用气。在2 0 0 7年续建时改成调峰站,储罐内的液态天然气通过增压器增压至0 .5MPa后再通过LNG…     

LNG加气站联合卸车工艺设计的探讨

提出LNG加气站联合卸车过程中遇到的主要问题(槽车液化天然气不易流进增压器,无法给槽车增压,以至于卸车困难),分析其原因,给出了改进方案.     

LNG橇装汽车加气站工艺流程与设备选型

LNG橇装汽车加气站将LNG储罐、加气机、低温泵、卸车增压器、储罐增压器、管道、控制阀门等设备集中固定安装在一个橇块上,适用于LNG汽车加气项目推广和其他小规模客户开发。以某公交站场的LNG橇装汽车加气站为例,从技术规范、技术参数、工艺流程和设备选型等方面进行了分析。     

使用液氮回收LNG加气站BOG的可行性分析

介绍常用的LNG加气站BOG回收方法及BOG排放量计算,探讨使用液氮回收LNG加气站内BOG的工艺流程和液氮量计算。将使用液氮回收BOG与常用的BOG回收方法进行对比,分析使用液氮回收BOG的优势。     

LNG卸车台防静电报警装置使用问题的研究

<正>1引言LNG槽车装卸区必须安装防静电报警装置,作业前通过防静电报警装置把槽车与储罐连接成等电位,消除静电危害。GB50156-2012《汽车加油加气站设计与施工规范》11.2.16要求"LNG罐车卸车场地内用于防静电跨接的固定接地装置,不应设置在爆炸危险1区"。但"防静电跨接的固定接地装置"是指那一部分,"爆炸危险1区"的中心点在那里,众说不一。     

压缩机在天然气槽车BOG回收中的应用

为减少常规LNG槽车卸车方式存在的缺陷带来的损失,在储配站搭建了一套基于BOG气体压缩机的LNG槽车卸车系统。结合无锡新区储配站具体实例,介绍了此套卸车系统的组成、工作流程以及系统搭建过程中改造工程的实施方案。最后结合此系统具体的运行监测数据,对系统的经济性进行了深入分析,总结了系统运行过程的优势与不足。     

液化天然气气化站中BOG储罐功能的探讨

总结了目前LNG气化站流程中蒸发气体(BOG)储罐的设置方式,通过对工艺流程的分析得出该种设置方式并不能储存BOG的结论。如果在BOG储罐之后设置阀门,则该储罐可储存一定量的气体,储气量与BOG储罐的容积、LNG储罐的工作压力、LNG储罐气相管道上BOG减压阀的设定启动压力及城市燃气管网的供气压力有关。稍具规模的城市燃气管网的水力工况能接受LNG气化站BOG的排放,在气化站内设置BOG储罐没有必要。     

张家港中集圣达因低温装备有限公司

正张家港中集圣达因低温装备有限公司是中集安瑞科控股有限公司(3899.HK)下属骨干企业,注册资金7.95×108元人民币。专业从事各类低温液体储罐、槽车、罐式集装箱、低温绝热气瓶等的设计、制造、销售和相关技术服务,并承接LNG/L-CNG汽车加气站、LNG气化站、LNG小型气化站、大型常压储罐、子母罐、球罐以及水上运输、加注、燃料储罐和供气系统等各类低温工程应用的总承包业务。公司具有A2、A3、C2、C3设计许可证,A2、A3、C2、C3、B3压力容器制造许可证,GCI压力管道安装许可证,美国机械工程师学会"ASME""U"、"S"和"T"钢印授权证书     

Assessment of bridges via monitoring

The prediction of a realistic life cycle and the extension of the service life is an important task in reducing costs of civil engineering structures in the future. The paper first gives an overview of the necessary steps of the overall procedure of a precise life cycle assessment. The knowledge of the existing, inherent damage of a structure is an essential prerequisite for life cycle prediction. A theoretical and an experimental approach to determine the inherent damage is described. The paper concludes with the presentation of a fairly precise method to assess the fatigue life cycle of steel bridges. The methods are developed besides others at the Collaborative-Research-Center “Monitoring of Structures” at the Technical University at Braunschweig, Germany.     

Network analysis via Markov processes

Although the practice of using Markov processes to analyse networks can be subjective owing to the probabilities and estimates involved, it is no more subjective than other techniques attempting to handle decision-making under conditions of uncertainty. The method does, however, offer the advantage of providing the decision-maker with a tool that he can use before a conventional network technique to help him decide whether or not the project should be undertaken.     

Batch monoethylamine degradation via nitrate respiration

Monoethylamine (MEA) degradation via nitrate respiration was evaluated in batch experiments using suspended growth bacterial cultures grown under low growth rate conditions. It was found that, under the conditions tested, MEA was highly degradable when the initial TOC/MLVSS ratio used in a batch experiment was < 0.35, beyond which, however, MEA inhibition was evident. The composition of the medium solution used to cultivate the bacterial cultures was critical in MEA degradation via nitrate respiration. In this study, the best MEA degradation was attained when cobalt (0.45 mg/l), copper (0.5 mg/l), molybdenum (0.5 mg/l), and yeast extract (1.0 mg/l) were all present in the medium solution. Ammonia was formed as an end product from MEA degradation via nitrate respiration. The MEA-N initially added in a batch experiment could be accounted for as NH⁺₄-N when the assimilatory requirements for nitrogen were negligible during the sampling period.     

Reliability of shells via koiter formulas

Probabilistic methods are being applied to Koiter formulas in order to derive the reliability of imperfection-sensitive shells, on this occasion by taking into account the randomness of both parameters appearing in the formulas — the initial imperfection and the allowable load. The results indicate the importance of the loading randomness, implying a dramatic reduction in the reliability with respect to traditional derivations which consider only the randomness of the initial imperfections.     

试验设计方法在结构优化中的应用

研究了试验设计中的均匀设计法在结构优化中的应用,提出了余表的概念,解决了搜索方向的问题,考察了体积约束条件下悬臂梁的刚度优化问题,并对优化过程及结果进行了分析,结果表明均匀设计法用于结构优化是可行的.     

Color removal via adsorption on wood shaving

Factors affecting the adsorption capacity of dyes on wood shavings, such as the mesh size of the adsorbent, wood dosages, contact time, and the structure of the adsorbant, were studied. Adsorption of dye on wood follows the classical Freundlich's isotherm. Available results indicated that wood shaving is a good adsorbent. Its capacity varies according to the structure of the dye and mesh size. Powdered activated carbon was used as a reference adsorbent for the same dyes under investigation.     

Adaptive Occupancy-based Lighting Control via Grey Prediction

This paper describes adaptive occupancy-based lighting control via Grey prediction. Determining the timing of automatically switching off the lights after the occupied space is vacated is quite challenging when trade-off between occupant's comfort and energy saving is concerned. The occupancy behavior is modeled by the well-known Pareto distribution for determining such delay time based on probability of no false off-switch. Since the occupancy behavior for determining the delay time at controlling time cannot be known in advance and dynamically changes, Grey prediction model is thus applied in order to determine the delay time according to the knowledge of that occupant's activity in the past. The real-time control implementation to lighting an office room is used to illustrate a viability of the proposed methodology in practical use for energy saving.     

价值工程在我国节能建筑推广中的应用探索

本文简介了价值工程的思想和我国经济发展面临的能源形势,在此基础上提出推广建筑节能是缓解能源危机的重要途径。提出了将价值工程的思想运用到我国节能建筑的推广上面,包括节能建筑的选择、建筑物的结构设计、材料选择、节能建筑的市场推广等。最后,提出了推广节能建筑的若干政策建议。