在役压力容器免耐压试验替代方法与管理模式研究

现代化大型企业中一些在役压力容器由于种种客观原因难以按照法规进行耐压试验,针对这一问题提出制定替代方法需要考虑的七个方面因素;研究了基于风险的检验方法和检验策略,并同我国现行定期检验规范进行了比较,提出可以借鉴风险评估的方法,为确定免除耐压试验替代方法提供依据;给出了制定事故应急预案的编制指南,最后提出大型企业在役压力容器免除耐压试验的安全管理模式框架。     

Thermisches Spritzen im Chemieapparate- und Maschinenbau – Anlagen,Werkstoffe, Anwendungen

Thermal spray technique in chemical equipment and machine construction – Plant, materials, applications . The metal spray technique originally used only for repair applications is nowadays also used for production of new equipment since the attainable life expectancy of the coated parts plus the possibility of using inexpensive basic materials result in a significant increase in economy. The use of thermal spray coats in the manufacture of chemical plant calls not only for high adhesion and freedom from pores and cracks but also for good corrosion resistance. The high technological level which has been reached in spray processes as well as the development of suitable spray materials have meant that a satisfactory solution has now been found to a large number of the problems that were still outstanding a few years ago.     

离子液体应用研究进展

由于离子液体具有较低的熔点、良好的导电性和可以忽略的蒸汽压等优点,引起了科学界和工业界的广泛瞩目.随着研究的日益深入,室温离子液体已经被开发和应用到诸多领域.对室温离子液体应用的研究进展进行了综述,详细介绍了离子液体在电化学、化学反应、分离过程以及在新材料等方面的应用.并对该领域的研究前景作了展望.     

Optimal cure cycles for the fabrication of thermosetting-matrix composites

Polymer-matrix composites using thermosetting resins as the matrix are increasingly finding use. However, a major impediment to their widespread commercial use is the high cost associated with their manufacture, arising from the long processing cycle times. This paper addresses the problem of determining cure temperature and pressure variations with time for a time-optimal manufacture of thermosetting-matrix composites subject to practical constraints. The optimal cure cycles are determined using the nonlinear programming scheme of sequential quadratic programming combined with a physical model base to simulate the process phenomena. The optimized cycles are shown to improve upon the manufacturer-recomended cycles as well as the improved cycles reported in the literature. The optimization results are reported for a wide range of resin materials, product specifications, and process constraints to illustrate their effects on the optimal cure cycles. Parametric studies are presented in terms of dimensionless groups to assess the combined effects of the product and process variables on the optimal cycles in a generalized manner.     

Development of technical catalysts

Heterogeneous catalysis is the backbone of the modern chemical industry. The successful development of technical catalysts requires a highly interdisciplinary approach and a permanent close interaction between catalyst and process development. Although many modern methods are available for the characterisation of catalytic materials, still no substitute for a pilot plant test is available. Therefore the application of representative testing conditions in the laboratory or pilot plant reactor is of crucial importance. In order to identify the relationships between the often complicated solid state synthesis process during catalyst manufacture, the structural properties of the catalyst and its performance, correlation analysis are used.     

Oxidation of Ethylene over Silver: Adsorption, Kinetics, Catalyst

Selective oxidation of ethylene to ethylene oxide over supported silver catalysts is not only one of the very few uses of that element as n catalyst of industrial importance, it also has been the basis for the manufacture of an important chemical intermediate that underlies the large glycol industry as well as the manufacture of a varied array of solvents and related chemical materials, The chemical reactions offer a classical example of selectivity for partial oxidation to ethylene oxide versus complete combustion to carbon dioxide and water.     

一种计算炭材料生产工作配方的新方法

提出了一种计算炭材料生产工作配方的新方法,把计算炭材料生产工作配方归结为一种非线性规划问题。文中给出了用于计算炭材料生产工作配方的通用数学模型,介绍了求解该数学模型的常用方法,并以MAT-LAB软件为工具示范了应用计算机求解该数学模型的过程,最后对该数学模型中的目标函数、各粒度级料配比的下限和数学模型的求解方法进行了讨论。     

Water-based release coatings: Paper machine

Recent advances in the technology of water-based release materials and, in particular, their adaptability for use with paper machines are discussed with respect to their influence on the manufacture of pressure sensitive tape. The potential benefits of these advances, such as all-water based silicone and non-silicone release materials, and all-water, fast, low-temperature curing systems are reviewed.     

Oxidation of Ethylene over Silver: Adsorption,Kinetics, Catalyst

Abstract

Selective oxidation of ethylene to ethylene oxide over supported silver catalysts is not only one of the very few uses of that element as n catalyst of industrial importance, it also has been the basis for the manufacture of an important chemical intermediate that underlies the large glycol industry as well as the manufacture of a varied array of solvents and related chemical materials, The chemical reactions offer a classical example of selectivity for partial oxidation to ethylene oxide versus complete combustion to carbon dioxide and water.     

Industrial applications for animal fatty oils

Some of the animal fats that are by-products of the meat packing industry can become a valuable commodity for certain other portions of our nation’s economy. This paper reviews the types of raw materials used, as well as the manufacturing techniques employed to manufacture these by-products into useful animal oils. The industrial uses for these oils include, not only petroleum and metal processing, but also the chemical and pharmaceutical industries. These oils also can be reacted chemically to produce various extreme pressure additives for the petroleum industry. In some areas it is even replacing the oil from the sperm whale whose use has been banned within the U.S. One of 12 papers presented in the Symposium “Novel Uses of Agricultural Oils” at the AOCS Spring Meeting, New Orleans, April 1973.     

锆材换热器的制作工艺

介绍了300 kt/a醋酸装置中锆材换热器制造的主要制作工艺和控制要点,为特殊材料设备制造积累了宝贵经验。     

Mineralogy of clay raw material from Burkina Faso and Niger used for ceramic wares

Some clay deposits in West Africa provide raw materials for the local and traditional manufacture of ceramic products. We selected three clays in Burkina Faso, with the references ROG, GRI and POT and a fourth one, AKN1 in Niger. These clays have been mined for many years. There is growing demand for such materials and the reserves are sufficient to meet this demand. The ROG and GRI clays are used as construction materials in both fired and unfired bricks. The POT and AKN1 clays are used for producing the porous ware of fired pottery. A study was carried out to look at some of the physico–chemical characteristics of these raw materials in order to enhance their use. This is a preliminary study which will be followed by further investigations into the production of different ceramic wares. An analysis of the chemical and mineralogical composition of the materials and some investigations of their fired properties during a firing cycle up to 1000°C has demonstrated that, taken as a whole, they possess satisfactory characteristics for the described applications.     

Analysis,modelling and simulation of hydrogen peroxide ultrapurification by multistage reverse osmosis

Very high purity chemicals are required for preparation of semiconductor materials and manufacture of printed circuit boards because low presence of metallic impurities is needed to avoid defects on silicon surface. Hydrogen peroxide is one of the most demanded chemical by the semiconductor industry and it must be submitted to ultrapurification processes to achieve the exigent requirements the chemical must fulfill to be accepted for semiconductor uses. In this paper, the potential of multistage reverse osmosis processes to reduce the metallic content of technical grade hydrogen peroxide below the limits fixed by the semiconductor industry is investigated. SEMI Grade 1 quality hydrogen peroxide was obtained by a two-pass reverse osmosis process in an experimental lab scale. A model based on Kedem-Katchalsky transport equations together with system material balances was proposed to describe the behavior of the installation. A full analysis of the influence of the design (recovery rates) and operation (applied pressures) variables over the performance of a simulated industrial scale plant was carried out. The economic viability of the simulated plant was demonstrated.     

Methoden und Anwendungen der statistischen Prozeß- und Qualitätskontrolle im chemischen Betrieb

Methodology and applications of statistical process and quality control in chemical plant. Statistical process and quality control, known respectively as SPC and SQC, presently command considerably attention. Originating with buyers of chemical products, the vocabulary and methodology of this area of expertise are increasingly entering the chemical plant. Appropriate use of these techniques is considered in the present article. A brief presentation of the philosophy of quality assurance in production using the methods of SPC and SQC is followed by a terse explanation of the goals and techniques of SPC/SQC. The applicability of the methods to process engineering is a special problem. Questions of the necessary adaptation and introduction into the conventional procedures of process control are discussed. Instrumentalization of plant with digital process controllers provides a framework for implementation of integrated solutions of such quality assurance systems in production. This is explained with the aid of examples.     

Das Zusammenwirken Technischer Regeln und technischer Entwicklungen für die Sicherheit von Chemieanlagen

Interplay of technical specifications and technical developments in the safety of chemical plant. In the planning, construction, and operation of chemical plant requiring close supervision the aims are defined by rules and regulations which refer back to a comprehensive compilation of technical specifications concerning the means by which these aims can be accomplished. These rules were, and are, worked out by business federations in collaboration with occupational and governmental agencies in joint committees. Since both practical experience and fresh knowledge resulting from technical developments are gained in industrial undertakings, the feedback of experience from industry ensuring continuous up-dating of the technical specifications is of immense importance. Starting from the current state of the art, the expert frequently has to work out solutions to specific problems. Once general conclusions which have proved their value in practice can be derived, they are incorporated in the technical specifications. Such a contribution to safety engineering is illustrated for a pressure vessel. The examples described range from the derivation of reliable criteria for assessing the danger of brittle fracture of high-strength steel pressure vessels to the development of preventative techniques of nondestructive testing of components. They also incorporate the development of design data for conservative dimensioning of safety valves for frothing mixtures and their safe release into the atmosphere as well as investigation of the pressures expected on explosion of flammable hydrocarbon/air mixtures.     

Verwertung der schweren Rückstands-Fraktionen im Hinblick auf den Umweltschutz

Utilization of residual oil fractions in the light of environmental protection . The conversion of residual fractions produced in refineries into raw materials of chemical industry offers an alternative to fueling in thermal power stations, which is noteworthy from an energetic as well as environmental point of view. Processes may be compared using some criteria as yardstick, which have been derived from the request for pollution abatement. The modern process of high-pressure gasification keeps in line with those criteria. It is considered as a source of large quantities of hydrogen and carbon monoxide. Furthermore a thermal power plant is considered, in which the flue-gas desulphurization is replaced by fuel desulphurization operated at high pressure. A comparison of processes shows typical productions and consumptions as well as thermal efficiencies. The remaining environmental pollution is also tabulated. Thermal efficiencies of chemical processes are remarkably higher than that of the power plant process.     

新型D形螺栓高压密封结构

通过将D形螺栓联接的高压密封与传统的双锥密封、卡扎里密封在结构、加工、密封可靠性、重量等方面进行对比,说明D形螺栓联接的高压密封结构具有结构紧凑、重量轻、加工简单、密封可靠、拆装方便等优点,是较为理想的高压密封装置,适用于经常装卸的高压设备和管道．     

Der Entwicklungsstand der Hochtemperatur-Verbrennung und Rauchgasreinigungstechnik — dargestellt an zwei laufenden Bauvorhaben

State of development of high-temperature combustion and flue gas purification — illustrated for two current construction projects. The state of the art in rotary furnace combustion plant is described with the aid of two current construction projects for a chemical plant and for a publicly accessible plant. The concepts of the plant are adapted to the waste material to be disposed of, the energy utilisation system, and disposal of the residual materials. Data for the chemical plant indicate higher concentrations and fluctuations in the flue gas constituents. Flue gas scrubbing is accomplished here by quenching, passage, through two rotary scrubbers, and wet electrofiltration. Scrubber liquid is passed to a company purification plant. In the other case, no waste water may occur. A two-field electrofilter and a two-stage milk of lime washer are employed. Washing liquid is passed to a waste water treatment unit with vacuum evaporation. Special process engineering measures are necessary to maintain pure gas values even in cases of pronounced concentration fluctuations. Household and special waste incineration are discussed increasingly from the viewpoint of NO_x reduction. Possible developments of SCR processes up to use of activated charcoal final purification stages are considered.     

Manufacture of Nonwovens Abroad

All existing types of chemical fibres, including the new generation (aramid, bicomponent, polyacrylate, etc.) are now actually raw material for nonwoven materials. More than 60 firms in Western Europe manufacture chemical, primarily synthetic, fibres for production of nonwovens by dry, wet, water-jet, thermobonding and ChemBonding, needle punch, and other methods, including melt spinning (spanbond/meltblown). The highest growth rates in manufacture and consumption of nonwovens is predicted for 2005-2010, where such consumption areas as geotextiles, construction, medicine, and others should have a leading role.     

Integrated Environmental Protection Reduces Water Pollution

In the manufacture of chemical products, undesirable residues are also produced. These frequently occur as polluted wastewater that leads to the formation of sewage sludge after end-of-pipe treatment. Effective reduction of these substances is an important aim of industrial environmental protection. Taking the example of chemical production, the author shows how this aim can be achieved by production-integrated environmental protection. The paper outlines the technical measures involved in this approach, the result that they bring and the inherent limitations. The associated cost criteria are also discussed. The two concepts of end-of-pipe technology and production-integrated environmental protection are compared.