催化剂级配技术在加氢改质装置上的工业应用

基于柴油产品质量升级的需求,中国石化大连石油化工研究院(FRIPP)开发了FHIDW加氢改质技术及配套FF-46加氢精制催化剂、FC-14B加氢改质催化剂和FDW-3临氢降凝催化剂.该技术及催化剂级配体系在格尔木炼油厂0.8 Mt·a-1加氢改质装置上的工业应用情况表明,级配催化剂体系对原料适应性强,装置运转平稳,操作灵活性高,催化剂失活速率慢,产品分布合理且质量优异,在降低柴油产品凝点的同时可以明显改善其密度和十六烷值,解决了改造前装置生产重柴油密度偏低的问题,为炼油厂生产符合国V质量标准的柴油提供了技术保障.     

预硫化型FF-66/FC-20催化剂组合应用生产国Ⅵ低凝柴油

为实现柴油产品质量升级,选择抚顺石油化工研究院研制的新一代加氢精制催化剂FF-66替换原加氢精制催化剂FF-36,与加氢裂化催化剂FC-20组合使用生产国Ⅵ低凝柴油。结果表明,采用FF-66/FC-20组合催化剂处理催化柴油、焦化汽油和直馏柴油组成的混合原料(平均硫含量为2 742μg/g),标定工况下的柴油产品硫含量降低至4.5μg/g,氮含量降低至0.35μg/g,多环芳烃质量分数降低至3.3%,十六烷值提高了3.5个单位,凝点降至-24℃。说明FF-66/FC-20催化剂活性匹配良好,具有优异的脱硫、脱氮性能和十六烷值增值能力,能够满足柴油加氢改质异构降凝装置生产国Ⅵ低凝柴油的需求。     

FF-36/FC-32A组合催化剂在加氢改质装置上的应用

详细介绍了FF-36加氢精制催化剂和FC-32A加氢裂化催化剂在柴油加氢改质装置上的工业应用。精制催化剂具有反应温度上与裂化催化剂相匹配的加氢脱氮能力,FC-32A具有显著优先裂解重组分能力、开环选择性以及显著提高柴油十六烷值能力。工业标定结果表明,产品汽油、轻质柴油、柴油的硫、氮质量分数均在10-6g/g以内,汽油的脱硫率为98%、脱氮率为99%,轻质柴油脱硫率为99%、脱氮率为99%,柴油脱硫率为99%、脱氮率为99%,达到设计要求。汽油的辛烷值和柴油的十六烷值以及指标达到设计要求。     

FF-66/FC-52组合催化剂在柴油加氢改质装置上的应用

分析了FF-66及FC-52型催化剂在某公司1.5 Mt/a柴油加氢改质装置上的应用情况。工业应用表明,在反应压力11.5 MPa、精制床层平均温度360℃、裂化床层平均温度369℃的条件下,产品柴油硫、氮质量含量均小于2.0μg/g,石脑油收率由14.5%增加至32.9%,产品柴油收率由50.9%下降至39.4%,装置柴汽比由3.22下降至1.20。FF-66、FC-52催化剂具有优异的加氢脱硫、脱氮活性和较高的石脑油产品选择性。该催化剂级配体系的成功应用,可以为同类装置制定油品质量升级及降低柴汽比方案提供一定的借鉴意义。     

FF-33催化剂在蜡油加氢处理装置的工业应用

某公司2.3Mt·a-1蜡油加氢处理装置第五周期采用大连石油化工研究院开发的FF-33主催化剂及FZC系列保护剂。介绍了催化剂FF-33初期标定结果及日常工业应用情况。结果表明:催化剂FF-33具有优异的加氢脱硫性能及良好的稳定性,能满足装置长周期运行要求。     

FF-24催化剂在镇海炼化蜡油加氢装置的工业应用

中国石化镇海炼化分公司为了提高180万t/a蜡油加氢装置运行效果(尤其是提高加氢脱氮率),于2012年换用抚顺石油化工研究院最新开发的蜡油加氢处理专用催化剂(FF-24)。要介绍了FF-24催化剂在中国石化镇海分公司180万t/a蜡油加氢装置的工业应用情况。工业应用结果表明:FF-24催化剂生产方案灵活,活性稳定性好,能满足生产优质低硫催化裂化原料及精制柴油的需要。     

经济型轻蜡油加氢改质降凝工艺的开发及工业应用

一重集团大连工程建设有限公司开发的轻蜡油加氢改质降凝工艺具有对原料油和已有加氢装置适应能力强、操作灵活性大及柴油产率高等特点。该工艺技术关键是使用自主开发的HPH型加氢精制催化剂及具有异构和裂化多功能的HPC型加氢改质催化剂。工业应用结果表明,该工艺能够对原料油进行深度加氢精制脱硫、脱氮,芳烃深度加氢饱和,产品收率高,有效降低柴油产品的凝点、密度和馏程,显著提高柴油的十六烷值,是经济型生产清洁柴油的优选工艺,具有广阔的应用前景。     

塔河炼化柴油加氢改质MHUG装置长周期运行分析

为应对柴油质量升级,中国石化塔河炼化对现有的100万吨/年柴油加氢装置进行了技术改造。本次改造采用石油化工科学研究院开发的柴油加氢改质MHUG技术和高性价比柴油加氢改质RIC-3催化剂。本文对该装置加工焦化汽柴油生产低硫高十六烷值清洁柴油长周期运行情况进行了分析。截止至2019年4月25日该装置已经连续稳定生产国V柴油累计903天。运转分析结果表明,生产国V柴油期间,精制反应器平均反应温度为340～350℃,改质反应器平均反应温度为338～361℃。综合考虑原料性质和焦化汽油加工比例的变化对催化剂寿命的影响以及反应器压降等因素,100%满负荷运转时,催化剂连续运行时间可达到4年。     

新催化剂级配技术的工业应用

中国石油大庆炼化公司加氢改质装置2010年更换由中国石化抚顺石油化工研究院研发的FH-98/3963/FDW-3加氢改质降凝组合催化剂，改进了降凝反应器催化剂装填方式。工业应用结果表明，组合催化剂级配合理，新的装填模式的运用提高了柴油收率，同时降低了装置能耗     

加氢裂化装置的工艺优化改造设计

国内某炼厂0.8 Mt/a加氢裂化装置由于所产柴油产品产率偏低、密度偏低,导致全厂仅能生产调和硫含量低于350μg/g的国Ⅲ标准车用柴油产品。根据柴油国V质量升级的需要以及目前装置运行过程中存在的问题,对该装置进行技术改造,催化剂更换为抚顺石油化工研究院开发的FF-46加氢精制、FDW-3临氢降凝和FC-14B加氢改质催化剂组合,采用加氢改质(降凝)操作模式,由一段串联全循环工艺流程改为一段串联一次通过工艺流程,装置改造后可以生产硫含量低于10μg/g的国V标准车用柴油产品,柴油产品密度由800~805 kg/m3提高至812~810.4 kg/m3,柴油产品产率由50.46%提高至88.90%~97.20%。同时考虑到装置原料变差的可能性,通过切换操作,工艺流程可以由一段串联一次通过工艺流程恢复至一段串联全循环工艺流程,给原料加工和生产操作带来极大的适应性。     

Mesomorphic transitions in a mixture of a flexible and a semi-rigid polymer

Phase studies on a mixture of two polymers are presented, one of which is mesomorphic. We have systematically examined the influence of the molecular weight of the flexible polymer (including the oligomers) and of the semi-flexible polymer. In addition to the effect of the molecular weight, specific interactions are important for compatibility and formation of a homogeneous mesomorphic phase. The nature of this phase is demonstrated to be cholesteric and the pitch is determined.     

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.     

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.     

Detonation of a Column of a Chemically Active Bubbly Medium in a Liquid

The problem of a detonation wave propagating in a cylindrical column of a chemically active bubbly medium screened by a liquid from the tube walls is formulated and numerically solved within the framework of the Iordanskii–Kogarko two-phase model with allowance for energy dissipation due to acoustic radiation of bubbles. The wave structure of the reaction zone and the detonation velocity of the bubbly medium column are calculated. It is found that the self-sustaining wave can propagate with a velocity greater than the velocity of one-dimensional bubble detonation by a factor of 1.5–2.5.     

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     

Propagation of a burning front over a condensed material from a focus

Measured propagation speeds are given for the combustion front in a blind gap in a condensed substance, which are related to gap height and mean pressure. The front may propagate monotonically, which is characteristic of relatively high pressures and wide gaps, or as a result of additional burning foci arising at a certain distance from the main front. At low pressures and particularly with small gap heights, the front propagates in an unstable fashion over the surface.Moscow. Translated from Fizika Goreniya i Vzryva, Vol. 28, No. 4, pp. 49–53, July–August, 1992.     

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.     

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.