页岩气开发及应用展望

近期,美国页岩气开发技术突破,天然气产量迅猛增长,从而跃升为全球第一大天然气生产国。对于我国这个以煤炭为主导的能源消费大国来说,页岩气发展也正在被寄予厚望。从分析页岩气的基本特点入手,描述页岩气开发可能涉及到的专业设备与关键技术,参考美国页岩气的发展历程,结合我国页岩气发展的现状与形势,最终对我国页岩气开发和应用进行了展望。     

基于MSC.ADAMS的动力传动系统建模与仿真

根据动力传动系统的组成及工作原理,在MSC.ADAMS中分别建立了发动机、液力变矩器、齿轮传动、离合器的动力学模型,并组装成动力传动系统虚拟样机,采用仿真剧本进行总体仿真。结果表明,利用MSC.ADAMS进行动力传动系统仿真具有一定的优越性。     

闭式液压行走系统在甘蔗联合收割机中的应用研究

闭式液压行走系统在农业机械设备,尤其在甘蔗联合收割机中广泛应用,论述了闭式液压行走系统的工作原理、调速的实现方法,提出了甘蔗联合收割机差速及同步驱动控制的实现思路,为推进闭式液压行走系统在农业机械的应用提供借鉴与参考。     

浅谈如何实施HXD1型交流传动电力机车焊接质量控制

重点从焊接过程质量控制、首件评审和转序控制、标识和追溯性控制、不合格品控制、人员要求等方面,阐述了深度国产化HXD1型八轴交流传动电力机车焊接质量控制。面对工期短、焊接质量要求高、焊接量大等难点,明确了实施要求,规范了管理,使过程得到有效控制,圆满完成了该机车的生产试制任务。     

蒸汽喷射器的腐蚀与修复

介绍了脱碳流程中蒸汽喷射器的腐蚀情况及修复措施,并对腐蚀的机理作一探讨。     

油田绿色开采技术——CO2驱油

对于现在的社会来说,环保、“绿色”成为了现在工业化的标准。对于石油和天然气工作者来说,注CO2不仅能够减少向大气中排放CO2的量,同时还能够将以往认为是废气的CO2利用起来,提高油田的采收率。因此,CO2驱油已经引起世界各国越来越多的注意。本文介绍了CO2驱油技术的发展历史、CO2驱油提高采收率的技术机理、CO2驱的特点及存在的问题。最后根据以上调研CO2驱的特点,对CO2驱今后的发展提出了几点建议。     

Heat-integrated reactor concepts for catalytic reforming and automotive exhaust purification

Optimal solutions in environmental catalysis require a well-coordinated development of catalysts and of process design. This contribution is devoted to energy integrated design concepts for fuel reforming and for automotive exhaust purification. The examples presented demonstrate the importance of an innovative process design for optimal utilization of existing catalysts and show the potential of future developments.

New concepts for steam reforming through the efficient coupling of the endothermic reforming reaction with an exothermic combustion reaction are discussed in the first part. These concepts have been implemented for methanol steam reforming in a counter-current reactor with distributed side feed of burner gas and for methane steam reforming in a modular reactor with a co-current reaction section for the endothermic and the combustion reaction and attached counter-current heat exchangers. Both applications employ the so-called folded sheet reactor design, which ensures an excellent heat transfer between the reforming and combustion channels and efficient heat recovery.

A similar design solution is introduced for the apparently different case of automotive exhaust purification. The proposed concept aims at decoupling exhaust after-treatment from engine control. Its main component is a counter-current heat exchanger with integrated purification stages for HC-oxidation, NO_X storage and reduction and soot filtering. A small catalytic burner at the hot end of the heat exchanger provides both heat and oxidizing or reducing agents on demand. A new soot filter design allows for safe soot filter regeneration.     

Effect of dopants on the performance of CuO–CeO2 catalysts in methanol steam reforming

Steam reforming of methanol was carried out over a series of doped CuO–CeO₂ catalysts prepared via the urea–nitrate combustion method. XRD analysis showed that at least part of the dopant cations enter the ceria lattice. The addition of various metal oxide dopants in the catalyst composition affected in a different way the catalytic performance towards H₂ production. Small amounts of oxides of Sm and Zn improved the performance of CuO–CeO₂, while further addition of these oxides caused a decrease in catalyst activity. XPS analysis of Zn- and Sm-doped catalysts showed that increase of dopant loading leads to surface segregation of the dopant and decrease of copper oxide dispersion. The addition of oxides of La, Zr, Mg, Gd, Y or Ca lowered or had no effect on catalytic activity, but led to less CO in the reaction products. Noble-metal modified catalysts had slightly higher activity, but the CO selectivity was also significantly higher.     

Adsorption and reactions of ethanol and ethanol–water mixture on alumina-supported Pt catalysts

The formation of surface species in the ethanol–water interaction and the reforming of ethanol have been investigated on Pt/Al₂O₃ catalysts and for comparison on the support. By means of infrared spectroscopy it was found that on Pt/Al₂O₃ not only adsorbed ethanol, different types of ethoxy species but also traces of acetaldehyde and a significant amount of acetate groups were detectable on the surface. The latter species were stable even at 700 K. The gas phase analysis of the ethanol-dosed surface showed at higher temperature considerable amount of ethylene in the case of Al₂O₃ and hydrogen in the case of Pt/Al₂O₃.

In the ethanol + water reaction the selectivity of H₂ and CO₂ formation at 723 K decreased in time, while that of ethylene increased. This trend was attenuated by increasing the following parameters: water concentration, metal loading and reaction temperature. It was assumed that this behavior of Pt/Al₂O₃ in the ethanol + water reaction can be attributed to the formation of surface acetate groups which hindered the reaction on the metal, although these species were located rather on the support.     

Hydrogen production in solar reactors

The present work summarizes the recent activities of our laboratory in the field of solar-aided hydrogen production with structured monolithic solar reactors. This reactor concept, “transferred” from the well-known automobile exhaust catalytic after-treatment systems, employs ceramic supports optimized to absorb effectively solar radiation and develop sufficiently high temperatures, that are coated with active materials capable to perform/catalyze a variety of “solar-aided” reactions for the production of hydrogen such as water splitting or natural gas reforming. Our work evolves in an integrated approach starting from the synthesis of active powders tailored to particular hydrogen production reactions, their deposition upon porous absorbers, testing of relevant properties of merit such as thermomechanical stability and hydrogen yield and finally to the design, operation simulation and performance optimization of structured monolithic solar hydrogen production reactors. This approach, among other things, has culminated to the world's first closed, solar-thermochemical cycle in operation that is capable of continuous hydrogen production employing entirely renewable and abundant energy sources and raw materials – solar energy and water, respectively – without any CO₂ emissions and holds, thus, a significant potential for large-scale, emissions-free hydrogen production, particularly for regions of the world that lack indigenous resources but are endowed with ample solar energy.