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Petrochemical Industry (petrochemical + industry)
Selected AbstractsSIMULATION OF THIN-FILM DEODORIZERS IN PALM OIL REFININGJOURNAL OF FOOD PROCESS ENGINEERING, Issue 2010ROBERTA CERIANI ABSTRACT As the need for healthier fats and oils (natural vitamin and trans fat contents) and interest in biofuels are growing, many changes in the world's vegetable oil market are driving the oil industry to developing new technologies and recycling traditional ones. Computational simulation is widely used in the chemical and petrochemical industries as a tool for optimization and design of (new) processes, but that is not the case for the edible oil industry. Thin-film deodorizers are novel equipment developed for steam deacidification of vegetable oils, and no work on the simulation of this type of equipment could be found in the open literature. This paper tries to fill this gap by presenting results from the study of the effect of processing variables, such as temperature, pressure and percentage of stripping steam, in the final quality of product (deacidified palm oil) in terms of final oil acidity, the tocopherol content and neutral oil loss. The simulation results have been evaluated by using the response surface methodology. The model generated by the statistical analysis for tocopherol retention has been validated by matching its results with industrial data published in the open literature. PRACTICAL APPLICATIONS This work is a continuation of our previous works (Ceriani and Meirelles 2004a, 2006; Ceriani et al. 2008), dealing with the simulation of continuous deodorization and/or steam deacidification for a variety of vegetable oils using stage-wised columns, and analyzing both the countercurrent and the cross-flow patterns. In this work, we have studied thin-film deodorizers, which are novel equipment developed for steam deacidification of vegetable oils. Here, we highlight issues related to final oil product quality and the corresponding process variables. [source] Hydrodynamic investigation of bubble-column reactors: effect of column configurationASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2010Abid Akhtar Abstract Bubble-column reactors are quite popular in the chemical, biochemical and petrochemical industries due to their relatively simple construction, favourable heat and mass transfer properties and low operating cost. Among the various design parameters, column geometry (configuration) has a significant impact on the overall throughput. In this study, an experimental investigation of the bubble-column configuration on its hydrodynamics has been conducted with three different sizes of the column (ID = 10,45 cm). A comparison in terms of the overall gas holdup as well as localised bubble properties is performed using the four-point optical technique and hydrodynamic similarities/dissimilarities are discussed. The study showed that the overall gas holdup was a function of the gas flow rate. For the range of gas velocity investigated (9.5,22.3 cm3/ min), the smaller column had 50,60% more holdup than the bigger column. Localised bubble properties exhibited similar behaviour (i.e. higher values for the smaller column). A comparative study of L/D illustrated an invariant behaviour at a high value of L/D (>5.5). A low L/D (,1.5), however, showed a prominent influence on hydrodynamics. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Inert Gas and Fuel Gas Influence on the Pressure Limits of Stability of AcetyleneCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 11 2003K. Holtappels Chemically unstable gases obtained in many processes of, for example, the chemical and petrochemical industries, can decompose explosively also in the absence of oxidizing agents. In order to avoid hazards resulting from explosion reactions, safety measures need to be developed. Key to such methods is the knowledge of stability limits of unstable gases. In the present paper, an experimental method for determining the pressure limits of stability of unstable gases and gas mixtures is presented. It has proved useful when examining C2H2/inert gas and C2H2/fuel gas mixtures. [source] Conflict, Collaboration and Climate Change: Participatory Democracy and Urban Environmental Struggles in Durban, South AfricaINTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 3 2010ALEX AYLETTArticle first published online: 28 JUN 2010 The South Durban Basin on the eastern coast of South Africa is home to both a large-scale petrochemical industry and a highly mobilized residential community. In a conflict cemented by apartheid-era planning, the community's campaigns to improve local air quality provide a test case for the value of conflict for participatory democratic structures. In the context of the work of the International Panel on Climate Change (IPCC), the South Durban Basin also provides an opportunity to push the boundaries of the established links between participation and the design and implementation of responses to a changing climate. Contributing to one of the main themes of the symposium, this article argues that the focus on collaboration and compromise within studies of governance and participation overlooks both the reality of conflict and its potentially positive effects. Addressing this requires particular attention to how power relationships influence processes of governance, and the role of civil society in balancing the influence of the private sector on the state. It also calls for a better understanding of conflict and collaboration as mutually re-enforcing elements of an ongoing and dynamic political process. Together, the elements of this critique help to build a more nuanced view of participatory urban governance: one that both better describes and may better facilitate the ability of urban populations to collectively, effectively and rapidly respond to the challenges of a changing climate. Résumé Le bassin Sud de Durban, situé sur la côte Est de l'Afrique du Sud, abrite à la fois un vaste secteur pétrochimique et une communauté résidentielle particulièrement mobilisée. Dans une lutte cimentée par un urbanisme datant de l'apartheid, les campagnes communautaires pour améliorer la qualité de l'air local testent la valeur de la lutte en faveur de structures démocratiques participatives. De plus, dans le cadre des travaux du Groupe d'experts intergouvernemental sur l'évolution du climat (GIEC), le bassin Sud de Durban offre une occasion de repousser les limites des liens établis entre la participation, d'une part, et l'élaboration et la mise en ,uvre de réponses au changement climatique, d'autre part. Contribuant à l'un des principaux thèmes du symposium, cet article montre que, compte tenu de leur focalisation sur la collaboration et le compromis, les études sur la gouvernance et la participation négligent la réalité de la lutte autant que ses effets positifs potentiels. Pour ce faire, il examine comment les relations de pouvoir modulent les processus de gouvernance ainsi que le rôle de la société civile visant àéquilibrer l'influence du secteur privé sur l'État. Il convient également de mieux appréhender lutte et collaboration comme des composantes qui se nourrissent mutuellement dans un processus politique permanent et dynamique. Les éléments de cette analyse critique, une fois réunis, aident àélaborer une vision plus nuancée de la gouvernance urbaine participative. Cette vision offre une meilleure description et peut faciliter l'aptitude des populations urbaines à réagir de façon collective, efficace et rapide aux défis du changement climatique. [source] Utilization of spent petrochemical sulfuric acid in the production of wet-process phosphoric acidJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 12 2005Andrzej Chojnacki Abstract The possibility of the application of spent sulfuric acid from the petrochemical industry in wet-process phosphoric acid technology was investigated. The effect of organic impurities in sulfuric acid from benzol acidic refining on the solubility of calcium sulfate hydrates is discussed. Solubility isotherms and regression equations for CaSO4,H3PO4,H2SO4,H2O (pure and containing impurities) systems are presented. Phase transition temperatures between dihydrate and hemihydrate calcium sulfate were determined. The difference between pure and polluted sulfuric acid systems observed is negligible over the range of typical wet-process phosphoric acid technology parameters. It is concluded that the application of spent sulfuric acid from benzol acidic refining does not have a negative influence on the crystallization process of dihydrate calcium sulfate and therefore can be applied in wet-process phosphoric acid technology. Copyright © 2005 Society of Chemical Industry [source] Vietnam unveils ambitious oil and gas plansOIL AND ENERGY TRENDS, Issue 12 2007Article first published online: 14 DEC 200 Vietnam has announced a series of plans to increase oil production and to establish a refining and petrochemical industry. At the same time, it is proposing to develop a series of gas discoveries. Many of the developments are ambitious, as is the timetable. Oil production is supposed to rise by over 50% within 2-3 years whilst gas is set to more than double by 2015. Some of the developments may prove too ambitious within the timescale proposed, particularly those in the downstream sector. [source] Predicting deflagration to detonation transition in hydrogen explosionsPROCESS SAFETY PROGRESS, Issue 3 2008Prankul Middha Abstract Because of the development in computational resources, Computational Fluid Dynamics (CFD) has assumed increasing importance in recent years as a tool for predicting the consequences of accidents in petrochemical and process industries. CFD has also been used more and more for explosion predictions for input to risk assessments and design load specifications. The CFD software FLACS has been developed and experimentally validated continuously for more than 25 years. As a result, it is established as a tool for simulating hydrocarbon gas deflagrations with reasonable precision and is widely used in petrochemical industry and elsewhere. In recent years the focus on predicting hydrogen explosions has increased, and with the latest release the validation status for hydrogen deflagrations is considered good. However, in many of these scenarios, especially involving reactive gases such as hydrogen, deflagration to detonation transition (DDT) may be a significant threat. In previous work, FLACS was extended to identify whether DDT is likely in a given scenario and indicate the regions where it might occur. The likelihood of DDT has been expressed in terms of spatial pressure gradients across the flame front. This parameter is able to visualize when the flame front captures the pressure front, which is the case in situations when fast deflagrations transition to detonation. Reasonable agreement was obtained with experimental observations in terms of explosion pressures, transition times, and flame speeds. The DDT model has now been extended to develop a more meaningful criterion for estimating the likelihood of DDT by comparison of the geometric dimensions with the detonation cell size. This article discusses the new models to predict DDT, and compare predictions with relevant experiments. © 2007 American Institute of Chemical Engineers Process Saf Prog 2008 [source] | ||||||||||