三聚氰胺与尿素联产工艺及技术改造

河南省中原大化集团有限责任公司采用联产技术对三聚氰胺尾气进行回收,并对原尿素装置进行改造,新增了11万t/a尿素生产装置,并配套增设了尿素水解装置、OAT水解装置、碳铵液回收装置和尿素熔化装置。各装置彼此联系,又相对独立,充分发挥了尿素装置和三聚氰胺装置的联产优势,降低了三聚氰胺的生产成本,确保了污染物的达标排放。     

提高硫磺回收联合装置硫回收率的研究

介绍了中国石油四川石化有限责任公司硫磺回收联合装置中酸性水汽提装置、溶剂再生装置及硫磺回收装置的特点.详细阐述了影响酸性水汽提装置、溶剂再生装置脱硫率以及硫磺回收装置硫回收率的因素,提出了提高联合装置硫回收率的相应措施,从根源上降低SO2排放,为炼厂环保装置的平稳运行提供参考.     

高压法三聚氰胺装置废水处理工艺研究与技改

中国石油乌鲁木齐石化分公司化工厂高压法三胺装置有两套废水处理装置,一套为欧技公司引进废水处理装置、另一套为东华工程科技股份有限公司(化三院)设计尿素解析水解装置。在装置试车过程中两套装置都出现问题,欧技公司的废水处理装置频繁堵塞,化三院的解析水解装置外排经常不达标。通过我们对两套装置运行特性的不断摸索研究,做出技改解决了换热器堵塞、外排不达标的问题,提高了装置的运行平稳率,降低了操作人员的劳动强度,既节能又能保证环保。     

催化裂化装置油浆换热系统改造分析

探讨了催化裂化装置油浆换热系统改造,通过对流程的优化,进一步实现了装置之间的热联合,降低了装置的总能耗,提高了装置的操作稳定性。     

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。     

双酚A装置基于风险检验技术的应用

对某企业双酚A装置进行风险评估,发现10%的设备和管道承担了装置90%的风险。随着时间的推移,装置风险有了较大增高,因此需要定期检验来降低装置风险。根据装置风险评估的结果制定检验方案,实践证明基于风险的检验更具针对性,也降低了装置的风险,为企业节约了成本。     

复合胎面挤出生产线的改造

为提高挤出胎面质量,对胎面挤出生产线的进料装置、温控装置、贴合装置、冷却装置、裁断装置、吹分装置、分检装置和存放装置进行全面改造,取得了良好的效果。     

催化裂化装置再生立管震动原因分析及处理

中海炼化惠州炼油催化裂化装置开工正常以来,再生立管现场震动很大,装置加工量未达到设计要求,装置效益低。根据此现象分析了装置运行中存在的问题并查找原因,提出解决措施,从而提高了装置的经济效益,保证了装置平稳运行。     

全密闭一体化生产装置在涂料生产中的应用

分析了国内涂料生产装置的落后和弊端,推出了一种全密闭一体化的涂料生产装置,该装置通过了自动控制系统实现了涂料生产的给料、合成、灌装的自动完成,该装置稳定高效,节能环保,代表了涂料生产装置的最新发展方向。     

10万t/a焦炉煤气制合成氨装置试运行总结

介绍了焦炉煤气制合成氨装置的工艺流程,简述了装置的试运行情况。结果表明,装置各项运行指标均符合设计要求,并及时解决了装置试运行中存在的问题。     

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.