低温甲醇洗装置扩产改造总结

通过对低温甲醇洗装置各系统的潜能分析,制定出低温甲醇洗装置的改造方案.分析了低温甲醇洗装置投运中出现的问题,提出相应的改进措施.改造后,低温甲醇洗装置产能提高,有较好的节能减排效果.     

鲁奇型低温甲醇洗工艺探讨

通过对鲁奇型低温甲醇洗装置运行的经验总结，提出了对低温甲醇洗工艺的新认识。概括论述了低温甲醇洗工艺的合理性和鲁奇型低温甲醇洗装置的工艺及运行特点，认为低温甲醇洗在煤制合成氨工艺中的应用是成功的。     

低温甲醇洗系统存在问题分析及解决办法

结合义马气化厂低温甲醇洗工艺运行情况,从低温甲醇洗工艺原理出发,就低温甲醇洗在生产中暴露出的问题进行物理化学分析,总结解决问题的方法.逐步提高对低温甲醇洗认识,保障实际生产中低温甲醇洗装置平稳运行,充分发挥低温甲醇洗装置的先进性、经济性及其环保性.同时,为提高企业的生存竞争力打下坚实的基础.     

低温甲醇洗系统存在问题分析及解决办法

结合义马气化厂低温甲醇洗工艺运行情况,从低温甲醇洗工艺原理出发,就低温甲醇洗在生产中暴露出的问题进行物理化学分析,总结解决问题的方法。逐步提高对低温甲醇洗认识,保障实际生产中低温甲醇洗装置平稳运行,充分发挥低温甲醇洗装置的先进性、经济性及其环保性。同时,为提高企业的生存竞争力打下坚实的基础。     

低温甲醇洗装置甲醇消耗问题探讨

煤化工行业进入了变革期,传统的生产工艺存在着非常大的能耗,影响了煤化工企业的生产效益。甲醇脱硫脱氮工艺环节,低温甲醇洗装置不可或缺,虽然这一装置在运行的过程中,有效去除了气体中的二氧化碳、硫化氢等气体,使酸性气体得以回收,减轻了传统工艺下的环境污染现象,但是,这一装置同样存在着一定的技术缺陷,就是甲醇消耗非常严重,因此,甲醇消耗控制是低温甲醇洗装置应用的关键。基于此,本文重点分析了在低温甲醇洗装置甲醇消耗方面的控制策略。     

低温甲醇洗装置运行中的设备问题及处理

在低温甲醇洗装置运行过程中,可能会出现一些问题对装置的运行造成不利影响,影响低温甲醇洗装置的应用效果,因此需要加强低温甲醇洗装置运行情况的研究,分析运行中出现问题的原因,采取措施及时的进行处理。本文以某煤化工公司的低温甲醇洗装置为例,介绍了该公司低温甲醇洗装置运行过程中出现的问题,对导致问题的原因进行了分析,提出了针对性的解决策略。     

低温甲醇洗制冷系统的优化

介绍低温甲醇洗工艺在HT-L粉煤气化制甲醇装置中运用出现的设计缺陷,通过技术改造,解决了低温甲醇洗制冷系统存在的问题,大大提高了装置的生产能力,生产成本也大幅下降。     

浅谈低温甲醇洗装置设备布置

结合低温甲醇洗装置设备布置实例以及在布置时遇到的问题,重点对影响低温甲醇洗装置设备布置的关键因素进行说明,通过对两种典型布置进行优缺点对比,明确低温甲醇洗装置布置的重难点及优化方向,希望能对以后提升和完善设备布置起到一定的参考作用.     

低温甲醇洗工艺的技术优化

介绍了低温甲醇洗工艺流程设置及特点,结合项目的实际情况对低温甲醇洗工艺进行了优化调整,在确保技术可靠、操作稳定的基础上,进一步优化装置能耗、降低操作费用、缩减装置投资,并为同等规模低温甲醇洗流程设置提供参考。     

低温甲醇洗装置技术改造能效分析

采用航天炉粉煤加压气化技术对300 kt/a甲醇生产厂气化装置进行改造,同时对配套低温甲醇洗装置进行改造优化。通过改造前、后能量平衡分析发现,改造后低温甲醇洗装置的热效率提高了6.0%;通过分析发现,改造后低温甲醇洗装置的损失降低1.8×107k J/h,效率提高3.5%。     

A comprehensive review of nanofiltration membranes:Treatment, pretreatment, modelling, and atomic force microscopy

Nanofiltration membranes (NF) have applications in several areas. One of the main applications has been in watertreatment for drinking water production as well as wastewater treatment. NF can either be used to treat all kinds of water including ground, surface, and wastewater or used as a pretreatment for desalination. The introduction of NF as a pretreatment is considered a breakthrough for the desalination process. NF membranes have been shown to be able to remove turbidity, microorganisms and hardness, as well as a fraction of the dissolved salts. This results in a significantly lower operating pressure and thus provides a much more energy-efficient process. Similar to other membrane processes, a major problem in NF membrane applications is fouling. Several studies have investigated the mechanisms of fouling in NF membranes and suggested methods to minimize and control the fouling of NF membranes. For NF membrane characterizations and process prediction, modeling of NF processes and the use of atomic force microscopy (AFM) are very important. The ability to predict the performance of NF processes will lead to a lower number of experiments, saving of time and money, and help to understand the separation mechanisms during NF. A comprehensive review of NF in water treatments is presented including a review of the applications of NF in treating water as well as in the pretreatment process for desalination; the mechanism as well as minimization of NF membrane fouling problems; and theories for modelling and transport of salt, charged and noncharged organic compounds in NF membranes. The review will also address the application of AFM in studying the morphology of membrane surfaces as part of the NF membrane characterization.     

浅析课程教学与教学相长

教学相长既是教学理念,又是教学方法,它是古人对教学和认知的一种哲学思想。通过目前对教学相长认识现状的分析,结合课程教学,构建了课程教学中的教学相长模型。该模型包含5种形式的教学相长模式,囊括了目前人们对教学相长的所有认识。通过具体的教学实践,阐述了5种教学相长模式的具体应用,证明了这5种模式在课程教学中的有效性,为教学相长在新时期的应用提供了实践和理论依据。     

NUMERICAL SIMULATION OF VOLATILE ORGANIC COMPOUNDS EVAPORATION IN CLOSED SPACES

Abstract

This paper deals with the simulation of VOCs concentration dispersion, evaporated from flooring materials, with the purpose of understanding VOCs evaporation and dispersion mechanisms. A test chamber is examined whose flooring material emits a number of VOCs. Given the area specific ventilation rate and considering it as boundary conditions, experimental data for the examined compounds concentration, the dispersion of the VOCs concentrations is examined under steady state and transient conditions. The model developed is used in conjunction with a general - purpose CFD code, PHOENFCS, that can provide detailed information on the flow as well as concentration fields. The results of the above two simulation cases are used as a guide for two other cases, where faster restoration of the air indoor quality was investigated by changing the ventilation rate in the chamber. The simulation results were used as a basis for further analysis for VOC evaporation for other flooring materials; this will allow proper material selection as well as proper ventilation system for a more healthy and comfortable environment in a building.     

Study on optimization of actinide oxalate precipitation process in a vortex flow reactor

Oxalate precipitation process is globally accepted and is the current choice for conversion of actinide nitrates to their oxides. A vortex flow reactor with magnetic stirrer is found to be a better option for a hassle-free operation of batch as well continuous actinide reconversion process. Utilization of magnetic stirrer as an alternate for the conventional mechanical stirrer eliminates corrosion-related issues as none of the metal parts are in contact with nitric acid as well as oxalic acid solution. Moreover, this alternative system ensures a maintenance-free process. Optimization of various process conditions in a vortex reactor was accomplished using cerium nitrate as a surrogate for actinide nitrate and the results obtained were compared with that of pitched blade mechanical stirrer. About 40 L of thorium nitrate solution was successfully precipitated by the optimized procedure in a vortex reactor.     

大型蒸汽管网系统放空阀、安全阀的设计选型

以某大型化工项目蒸汽管网系统的设计为实例,重点介绍了设计选型时对放空阀放空量和安全阀容量的选择要领、选取原则以及放空阀、安全阀开启压力值的确定方式.     

Orphics: Computer Graphics and the Feasibility of a Preferred Color Order

Because color has lost its permanent form in certain media such as computer displays, there is a need for some overriding organizational principle. In earlier work on orphics, this author has discussed some ideas and techniques for the fluid articulation of color in space and time without relying on a preferred color order. In this article the possibility of defining a sequence of colors arranged in a unique order, that is, general enough to serve as a tuning for the composition of color in space and time, is discussed. to gain as wide a perspective as possible, color vision theories and their relevance are discussed, as well as the structural compatibilities between color orders and the well-tempered musical scale. Finally the works of two artists, Morgan Russell and Robert Delaunay, are examined.     

Integration of a Gas Fired Steam Power Plant with a Total Site Utility Using a New Cogeneration Targeting Procedure

A steam power plant can work as a dual purpose plant for simultaneous production of steam and elec-trical power. In this paper we seek the optimum integration of a steam power plant as a source and a site utility sys-tem as a sink of steam and power. Estimation for the cogeneration potential prior to the design of a central utility system for site utility systems is vital to the targets for site fuel demand as well as heat and power production. In this regard, a new cogeneration targeting procedure is proposed for integration of a steam power plant and a site utility consisting of a process plant. The new methodology seeks the optimal integration based on a new cogenera-tion targeting scheme. In addition, a modified site utility grand composite curve （SUGCC） diagram is proposed and compared to the original SUGCC. A gas fired steam power plant and a process site utility is considered in a case study. The applicability of the developed procedure is tested against other design methods （STAR？ and Thermoflex software） through a case study. The proposed method gives comparable results, and the targeting method is used for optimal integration of steam levels. Identifying optimal conditions of steam levels for integration is important in the design of utility systems, as the selection of steam levels in a steam power plant and site utility for integration greatly influences the potential for cogeneration and energy recovery. The integration of steam levels of the steam power plant and the site utility system in the case study demonstrates the usefulness of the method for reducing the overall energy consumption for the site.     

Residual Stress Distributions in Ceramics

Residual stress distributions in ceramics can be calculated for a coordinate system fixed by the specimen geometry as well as for the crystal system. Computations were performed using alumina as a model system with the residual stresses caused by thermal expansion anisotropy. Mean values and standard deviations of the stress distributions are calculated for a plane stress as well as a plane strain scenario in a laboratory coordinate system and compared to distributions of stresses occuring along the a -axis and c -axis of alumina. In addition, stress fluctuations in the whole assembly of grains are compared with stress fluctuations within and between individual grains.     

NUMERICAL SIMULATION OF VOLATILE ORGANIC COMPOUNDS EVAPORATION IN CLOSED SPACES

This paper deals with the simulation of VOCs concentration dispersion, evaporated from flooring materials, with the purpose of understanding VOCs evaporation and dispersion mechanisms. A test chamber is examined whose flooring material emits a number of VOCs. Given the area specific ventilation rate and considering it as boundary conditions, experimental data for the examined compounds concentration, the dispersion of the VOCs concentrations is examined under steady state and transient conditions. The model developed is used in conjunction with a general - purpose CFD code, PHOENFCS, that can provide detailed information on the flow as well as concentration fields. The results of the above two simulation cases are used as a guide for two other cases, where faster restoration of the air indoor quality was investigated by changing the ventilation rate in the chamber. The simulation results were used as a basis for further analysis for VOC evaporation for other flooring materials; this will allow proper material selection as well as proper ventilation system for a more healthy and comfortable environment in a building.