S-zorb装置反应器顶过滤器长周期运行研究

通过对汽油吸附脱硫装置(以下简称S-zorb装置)反应器过滤器原理进行分析和中石化某炼厂S-zorb装置反应器过滤器ME101实际运行中出现的问题进行汇总,给出了本装置的解决方案,在实际生产中通过一些调整可以实现ME101长周期平稳运行。     

信息与动态

S-zorb催化汽油脱硫装置建成国内首套1.2 Mt·a-1S-zorb催化汽油脱硫装置于2007年5月下旬在中国石化燕山石化公司建成。装置投产后,可生产硫含量低于10μg·g-1的低硫清洁汽油。届时,中国石化燕山石化公司生产的全部汽油将达到欧Ⅳ排放标准。随着2008年北京奥运会的临近,北京市     

OCTM装置生产国Ⅴ汽油的工业实践

为满足国Ⅴ汽油生产需要,原设计为国Ⅳ汽油标准的OCTM装置通过优化原料、调整轻重汽油切割点、提高重汽油加氢反应深度、改进脱臭单元流程等途径,优化OCTM装置操作,降低硫含量,再与S-zorb汽油调和,从而满足国Ⅴ汽油质量指标。     

科技集粹

首套S-zorb催化汽油脱硫装置投运国内首套120万t/aS-zorb催化汽油脱硫装置于5月下旬在燕山石化公司建成。该装置投产后。可生产流含量低于10μg/g的低硫清洁汽油。届时,燕山石化生产的全部汽油将达到欧IV排放标准,满足北京市的环保要求。该装置是世界上第四套、国内第一套同类生产装置。     

双分散颗粒湍动床反应器的多尺度模拟及细粉夹带优化

S-zorb吸附脱硫工艺技术是生产超低硫含量汽油的关键技术。目前,S-zorb湍动床反应器内的细粉夹带严重,容易堵塞其顶部过滤器,是影响反应器使用寿命和工艺流程运行周期的主要原因。因此,深入研究其反应器内的吸附剂颗粒和细粉颗粒的运动行为对优化反应器和提升工艺运行效率非常重要。本研究采用多尺度计算流体力学方法对双分散颗粒S-zorb湍动床反应器进行了模拟研究,考察了减少细粉夹带的优化方案。首先,比较了不同非均匀EMMS-bubbling曳力模型和EMMS-ANN模型对双分散颗粒运动行为的影响,发现采用上述两个模型都能合理预测吸附剂颗粒的流动行为和浓度分布,但EMMS-ANN模型对细粉颗粒的夹带量预测与工厂实验值的偏差大于前者。考察了一系列设计改造方案对减少细粉夹带的影响,结果表明,适当增大沉降段圆柱高度和半径以及增设固相出口横管都有助于减少细粉夹带,其中在反应区和沉降段之间的过渡区增设固相出口横管以及增大沉降段半径的方案对减少细粉夹带最有效。研究结果将有助于S-zorb工艺的进一步优化和升级。     

综合信息

高效铁系脱硫催化剂工业应用；日本开发从CO2和H2直接生产二甲醚；首套S-zorb催化汽油脱硫装置投运；安庆石化炼油二部火炬气脱硫装置开车成功；复合型高效捕沫器获国家专利；解化合成氨原料路线改造成功；工程设计信息。[编者按]     

首套S—zorb催化汽油脱硫装置投运

国内首套120万t/a S-zorb催化汽油脱硫装置于5月下旬在燕山石化公司建成。该装置投产后。可生产流含量低于10μg／g的低硫清洁汽油。届时，燕山石化生产的全部汽油将达到欧Ⅳ排放标准，满足北京市的环保要求。该装置是世界上第四套、国内第一套同类生产装置。     

北京将用上超低硫清洁汽油

日前,国内首套120万吨/年S-zorb催化汽油脱硫装置在燕山石化建成,顺利实现中间交接.预计该装置投产后,可生产硫含量低于10ppm的低硫清洁汽油.届时,燕山石化生产的全部汽油将达到欧Ⅳ排放标准,满足北京市更高环保要求,在提升企业竞争实力,提高经济效益的同时,为改善首都环境质量,实现绿色奥运目标作出贡献.     

以生产轻芳烃为目的的催化重整装置原料拓展研究进展

中国炼油产能过剩,而以轻芳烃为代表的化工产品消费量持续增长,调整产品结构是当前炼油企业面临的重大问题。目前,炼油企业主要以催化重整工艺生产轻芳烃。介绍了以催化重整工艺生产轻芳烃对原料性质的要求,全面详细地综述了直馏石脑油、加氢裂化石脑油、催化裂化汽油、焦化石脑油、乙烯裂解抽余油、S-zorb汽油、3种煤基石脑油的组成和性质特点,以及将其作为重整原料所需要的加工工艺。未来,催化重整装置的原料将呈现多元化趋势,依据上述几种原料的性质特点,给出相应原料的预处理建议,为炼油企业拓展催化重整工艺生产轻芳烃原料的发展提供参考。     

茂名100kt／a丁二烯生产装置运行状态评价

论述了茂名100kt／aDMF法丁二烯生产装置的概况、装置运行状况以及装置综合性评价。从装置运行工艺指标执行情况、装置用能情况分析、装置动静设备运行评价等3方面对装置的运行状态进行全面分析,获得了100kt／a丁二烯装置运行过程中主要物单耗、能单耗、公用工程操作费、各设备运行数据,实现了对装置的综合性评价。     

Extraction into a flow of a fluid with a velocity gradient

Unsteady extraction from a system of semi-infinite capillaries to the flow of a fluid with a linear velocity gradient is studied. An assumption that the diffusion in the flow is a quasi-steady-state process is taken to obtain a linear equation for the local mass flux from the pore space, which involves fractional derivatives with respect to time and flow coordinate. Limiting solutions for the total diffusion flux at small and large times that cover the entire time interval are found.     

Drag of a cylinder moving near a wall in a yield stress fluid

The drag of a cylindrical obstacle moving at a constant velocity in a yield stress fluid close to a wall is studied experimentally and numerically. The wall influence has been explored for gap values between the cylinder of diameter D and the wall ranging from 0.01D to 100D, which corresponds, respectively, to hydrodynamic lubrication and to unconfined domain conditions. A model yield stress fluid (Carbopol gel) is used in the experiments. The viscous and plastic drag coefficients have been calculated and measured as depending on the Oldroyd number, in conditions where the yield stress effects are more important than those of viscosity and the inertia negligible. We have performed experimental and numerical validations in the Newtonian case and provided more specifically comparisons of our measured data on yield stress materials with those resulting from viscoplastic flow simulations. © 2018 American Institute of Chemical Engineers AIChE J, 64: 4118–4130, 2018     

Growth of a Bonelike Apatite Layer on a Substrate by a Biomimetic Process

A dense and uniform bonelike apatite layer was formed on a substrate by the following biomimetic method. The substrate was first placed on granular particles of CaO, SiO₂-based glass soaked in a simulated body fluid (SBF) with ion concentrations nearly equal to those of human blood plasma and then soaked in another fluid highly supersaturated with respect to the apatite. The thickness of the apatite layer increased in proportion to the soaking time in the second solution. The rate of increase in the thickness of the apatite layer increased from 0.5 to 7.0 μm/day with increasing temperature of the second solution from 10° to 60°C, increased from 0.15 to 1.7 μm/day with increasing ion concentrations of the second solution from 0.2 to 1.5 times those of the SBF, and doubled by shaking the second solution. These results indicate that the growth of the apatite layer is controlled by mass transport across the interface between the crystal and the fluid.     

Electrolytes: From a Thorn Comes a Rose,and from a Rose,a Thorn

In this article we take a stroll through the metaphorical rose garden, part of the flower garden, that is electrochemical storage systems. We take a closer look at batteries as the center‐pieces – the roses – and especially at the system component of batteries, the electrolyte and its development, throughout history. Just as a rose can only develop its unique beauty when taken good care of and provided with clean water and suitable nutrients, a battery cell cannot function without its electrolyte; the seemingly trivial component that has to juggle a multitude of requirements in order to make batteries truly bloom.     

Motion of a large object in a bubbling fluidized bed with a rotating distributor

This work studies the effect of a low-frequency rotating distributor on the motion of a large object immersed in a bubbling fluidized bed. The object size and density differ from those of the inert solids that conform the bed. Examples of objects moving in a bubbling fluidized bed include passive particles, catalysts and reactants. The rotation modifies the bed dynamics in the surroundings of the distributor and affects the motion of the object within the bed.A set of experiments was carried out in a lab-scale cylindrical bed, equipped with a perforated plate distributor that can rotate at around 1 Hz, for different bed aspect ratios, gas velocities, and object characteristics. Sizes were far larger than that of the solids of the dense phase and densities ranged from half the bed density to values around it. The experiments were video recorded, capturing the surface of the bed from above.As have often been noted, objects might remain in stagnant regions near the distributor and be “lost” or precluded to circulate. This can be avoided in most practical cases forcing the distributor to rotate. Also, the effect of rotation on the circulation time of the objects is presented, showing a general reduction of large circulation times.     

Behaviour of a large bubble flowing through a sudden constriction between a cylindrical pipe and a rectangular cross section channel

The behaviour of a single large bubble flowing through a sudden constriction between a cylindrical pipe and a channel of rectangular cross section is studied experimentally. Two types of constrictions are considered: an abrupt one and a smooth one. Image analysis displays the deformation of the large bubble generated in the upstream vertical pipe and flowing through each kind of constriction. Image processing allows an estimate to be made of the velocity of Dumitrescu bubbles upstream of the constriction and the velocity of a 2D cap bubble flowing downstream of the constriction in a rectangular-cross-section channel. When the large bubble flows through a constriction, its behaviour can be considered in two steps: a first step corresponding to the disengagement of the large bubble and a second step corresponding to its transient behaviour after detachment. In terms of disengagement, an abrupt constriction induces systematic break-up of the large bubble whereas, with a smooth constriction, the large bubble undergoes strong deformations but does not break up. After detachment, large bubbles relax in a similar way and their velocities tend towards the terminal velocity of the 2D cap bubble.     

When is a Beam a Plate?

Formulas associated with simple beam or plate theories are used extensively in structural design, to determine You's modulus, and to determine fracture strength of brittle nonmetallic materials. The question may arise as to whether the proper ratio of beam-width-to-beam-depth is such that the bent structural element can be considered as a beam and, if not, what is the correction factor that should be used with the simple beam formula. These questions are answered for a range of structural metallic and brittle nonmetallic materials.     

Validating a fertilizer recommendation across a diverse cropping environment

One of the major objectives of on-farm research is to test and refine recommendations coming from controlled research conditions to suit the variable conditions met under farmer circumstances. In developing countries, resources available for agricultural research are limiting. Therefore the challenge is to develop methodologies favouring resource–use efficiency and facilitating relatively fast results. At the same time researchers must take advantage of a high level of farmer participation and sample environmental variables suspected of affecting the technology's performance. In this context, ways in which to deal with variability, both in terms of environment as well as in farmer management, become important. To present lessons learned, this case study describes first relevant aspects of the farming system, a brief history of the problem and the resulting experimental program. For illustration purposes, one year of data is presented in detail. This came from a farmer-implemented, farmer-managed test on urea use (30 kg/ha nitrogen) in rice cultivation based on water harvesting.Variation in rice yields has been investigated in order to determine whether known differences in cultivation circumstances (water level during fertilizer application, field position on the slope, rice variety used) warrant refining the recommendation regarding urea use. It is known for example that water height varying at application time can significantly influence the rice crop's response to nitrogen; however, in this investigation urea use proved to be an economically attractive option over the water level range investigated (5–15 cm).Although variable response to urea use due to environmental factors was identified, economic evaluation using Marginal Rates of Return showed that under all conditions urea use was justified. Therefore, the recommendation does not need to be refined, given the assumptions presented.Finally, the sustainability of urea use is discussed, in view of the fact that nitrogen application enhances crop yields and therefore increases the extraction of other crucial plant nutrients.     

Optimizing the size of a CFRP patch to repair a crack in a thin sheet

One of the several techniques to repair cracks in structural sheets consist in bonding polymer composite patches. The effectiveness of the repair for restoring the quasistatic strength of the structure depends largely on the adhesively bonded interface. The interface fails due to interfacial separation caused by the high peeling and shearing stresses. The geometrical dimensions, that is, patch length and width, have significant effect on the interface separation and they need to be optimized. The failure strength of the patch was determined by a numerical analysis using the cohesive zone model. Twenty-five numerical analyses were carried out as per the L-25 Taguchi orthogonal array followed by ANOVA which indicated the greater contribution of the patch width toward the failure of the patch. The failure stresses thus obtained were used to generate a response surface in ANSYS Design Explorer Module. A design criterion in terms of the percentage increase of the failure stress over the yield stress of the skin was used for minimizing the area of the patch. The optimum length and width of the patch corresponding to the minimum patch area were obtained by plotting the response curves generated from the response surface.