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排序方式: 共有1307条查询结果,搜索用时 46 毫秒
1.
《International Journal of Hydrogen Energy》2022,47(32):14674-14686
Reformed exhaust gas recirculation technology has attracted great attention in internal combustion engines. A platform of an exhaust gas-fuel reformer connected with the marine LNG engine was set up for generating on-board hydrogen. Based on the platform, effects of the methane to oxygen ratio (M/O) and reformed exhaust gas ratio (REG) from the reformer and excess air ratio (λ) from the engine on the components, hydrogen yield, thermal efficiency and reforming process of the reformer were experimentally investigated. Results shown that hydrogen-rich gases (reformate) can be generated by reforming the mixture of engine exhaust gas (about 400 °C) and methane supplied via the reformer with Ni/Al2O3 catalyst, and the hydrogen concentration of reformate was between 6.2% and 12.6% by volume. The methane supplied rate and λ affected the components and temperature of the reactant in the reformer, while REG changed the gas hour space velocity during the exhaust gas-fuel reforming processes, resulting in the difference in the components of the reformate and thermal efficiency. At the present experimental condition, the highest H2 concentration reformate was generated under the M/O of 2.0, λ of 1.55 and REG of 6%. 相似文献
2.
《International Journal of Hydrogen Energy》2020,45(60):34927-34937
Transporting energy in liquefied forms results in reduction in volume, which enables energy to be transported economically over long overseas distances. In this study, liquefied natural gas, liquid ammonia and methanol are proposed to transport the energy of natural gas in different forms to overseas. Due to temperature difference between the energy storage medium and the ambient, a portion of liquefied energy carriers mass is lost as boil-off gas (BOG). Therefore, a technical assessment based on energy and exergy analyses is conducted in this work to assess the total required energy and losses due to BOG for each energy carrier. To make a fair comparison among the energy carriers, the ship volume capacity is the fixed factor. The results show that the total daily energetic BOGs for LNG, ammonia, and methanol are calculated as 0.610%, 0.098%, 0.034% while the exergetic BOGs are 0.491%, 0.068%, 0.032%, respectively. Ammonia and methanol generate significantly less daily BOG, respectively, compared to LNG during the full supply chain, which make them alternative for efficient energy carrier transport. 相似文献
3.
In this paper we apply self-optimizing control (SOC) to a cascaded LNG liquefaction plant. We first introduce the model, and then define the operational objective, which is to achieve minimal energy consumption while satisfying operational constraints. Four control structures are compared; a “standard” temperature control structure, an SOC structure with two plant measurements, an SOC structure that uses a combination of plant measurements as controlled variable, and an SOC structure where we also include measurements of disturbances in addition to the plant measurements. We find that the SOC structures significantly reduce the average steady-state loss when the operating conditions change. We furthermore find that using more plant measurements in the SOC structure results in lowered losses. In particular, for the disturbances considered, the steady-state loss becomes acceptably low, such that there is no need for a supervisory real-time optimization layer. Finally, it has been found that including disturbance measurements results in somewhat reduced losses, although the improvement was insignificant for the studied case. The effectiveness of the SOC framework is shown by closed-loop step responses to selected disturbances. 相似文献
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5.
低温控制阀是LNG接收站操作控制中的主要执行单元,控制阀的正确选型是保证阀门正常运行及工艺操作的关键环节。该文具体分析了LNG接收站低温控制阀的选型设计要点,包括阀门类型、材料选择、特殊设计、口径选择、执行机构、低温试验等。 相似文献
6.
Determining and reducing the measurement uncertainty of LNG energy transfer in custody transfer operations is considered extremely important and challenging for industry. The European Metrology Research Programme (EMRP) for Liquefied Natural Gas (LNG) has been focused on reducing the uncertainty in the evaluation of LNG energy transfers by improving existing measurement methods, validating new measurement methods and development of new traceable calibration systems. Part of this project was to produce realistic measurement uncertainty budgets and to determine the sensitivity of the overall LNG energy transfer uncertainty to changes in the composition and temperature of different LNG cargoes.This paper provides details on the development of an uncertainty budget and the results from the sensitivity study. It was found that the uncertainty in the LNG energy transfer ranged from 0.56% to 0.77% when using the uncertainty budget for 461 LNG cargoes. The variation was mainly due to the difference in the LNG composition and its associated uncertainty. 相似文献
7.
介绍了LNG储罐用06Ni9钢板的技术要求。针对生产中06Ni9钢板性能控制、表面质量控制及超极限规格轧制板形控制的难点问题,经试验及现场实践,提出了相应的控制措施,如优化化学成分设计、优化轧制工艺和热处理工艺,保证了钢板的性能;板坯表面喷涂专用防氧化涂料,并配合合理的除鳞工艺,保证了钢板的表面质量;优化坯料、辊型设计,改进模型参数,保证了极限规格钢板的板形质量。在此基础上,太钢成功开发出LNG工程用06Ni9钢板。 相似文献
8.
简述了国内首套焦炉气甲烷化制LNG的工艺原理、工艺流程,介绍了其重点工艺单元和催化剂:焦炉煤气净化、甲烷合成催化剂、甲烷合成工艺、合成气低温液化等。利用自主研发的预还原催化剂以及绝热型反应器和换热型反应器组合形成的焦炉煤气甲烷合成新工艺,可保证合成气中CO2体积分数小于50×10-6,甲烷合成反应更完全。工业运行结果表明,该装置具有工艺简单、操作平稳、设备投资少、能耗低等特点。 相似文献
9.
与管道天然气相比,俄罗斯LNG产业的发展可谓相形见绌。受全球市场影响,俄罗斯决心大力发展LNG,2013年11月俄联邦政府批准LNG出口自由化法案。该法案的颁布将有助于LNG产业的快速发展,提高俄罗斯LNG在国际市场的份额,但同时也面临来自美国和加拿大等竞争对手的压力。俄罗斯未来的LNG出口出现较大幅度增长将会是不争的事实,将影响亚洲乃至全球LNG市场,同时对地缘政治局势也有一定的影响。 相似文献
10.