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2nd IFAC Workshop on Automatic Control in Offshore Oil and Gas Production, OOGP 2015

作者： Peixoto, Alessandro Jacoud Pereira-Dias, Diego Xaud, Arthur F. S. Secchi, Argimiro Resende PEE/GOPPE/UFRJ Department of Electrical Engineering P.O. BOX 68.504 Rio de Janeiro RJ21.945-970 Brazil Non-Destructive Testing Corrosion and Welding Laboratory Rio de Janeiro RJ21.945-480 Brazil PEQ/COPPE/UFRJ - Chemical Engineering Program P.O. BOX 68502 Rio de Janeiro RJ21.941-914 Brazil

This paper addresses the design of a perturbation-based extremum seeking control (ESC) method to maintain the oil production around the optimum point of the well-performance curve in gas lifted wells. The method uses periodic perturbation which is injected into the plant with intention to extract the information about the gradient of the well-performance curve. A simple nonlinear dynamic model is proposed and the essential dynamics of the Eikrem's model are captured, i.e., the transient behavior and the optimal steady state wellperformance curve. Based on this simple model, a pre-compensation is developed which allows the application of the ESC scheme without reducing excessively the perturbation frequency. The control performance is evaluated via numerical simulations using an appropriate environment for modelling, simulation and optimization (EMSO) of process dynamic systems. © 2015, IFAG (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.

关键词： Process control

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Modelling and Extremum Seeking Control of Gas Lifted Oil Wells

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IFAC-PapersOnLine 2015年第6期48卷 21-26页

作者： Alessandro Jacoud Peixoto Diego Pereira-Dias Arthur F.S. Xaud Argimiro Resende Secchi PEE/COPPE/UFRJ - Department of Electrical Engineering P.O. BOX 68.504 Rio de Janeiro RJ 21.945-970 Brazil Non-Destructive Testing Corrosion and Welding Laboratory Rio de Janeiro RJ 21.945-480 Brazil PEQ/COPPE/UFRJ - Chemical Engineering Program P.O. BOX 68502 Rio de Janeiro RJ 21.941-914 Brazil

This paper addresses the design of a perturbation-based extremum seeking control (ESC) method to maintain the oil production around the optimum point of the well-performance curve in gas lifted wells. The method uses periodic perturbation which is injected into the plant with intention to extract the information about the gradient of the well-performance curve. A simple nonlinear dynamic model is proposed and the essential dynamics of the Eikrem's model are captured, i.e., the transient behavior and the optimal steady state well- performance curve. Based on this simple model, a pre-compensation is developed which allows the application of the ESC scheme without reducing excessively the perturbation frequency. The control performance is evaluated via numerical simulations using an appropriate environment for modelling, simulation and optimization (EMSO) of process dynamic systems.

关键词： extremum seeking control oil production process control gas lifted wells

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LaCoO3 perovskite on ceramic monoliths - Pre and post reaction analyzes of the partial oxidation of methane

LaCoO3 perovskite on ceramic monoliths - Pre and post reacti...

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作者： Brackmann, R. Perez, C.A. Schmal, M. Federal University of Rio de Janeiro Chemical Engineering Program NUCAT/PEQ/COPPE Bl. G 128 C. P. 68502 CEP 21941-914 Rio de Janeiro RJ Brazil

Powder LaCoO3 perovskite were synthesized using Pechini's methodology. The γ-Al2O3 was deposited on the commercial cordierite ceramic substrate by washcoating. The perovskite was deposited over the monoliths by dip coating with a 80 g/l LaCoO3 suspension. The LaCoO3/γ-Al2O3/cordierite system was characterized by XRD, SEM, TPR and XPS. Results showed that the crystallite sizes of the perovskite remained unchanged after its deposition. XRD results identified LaCoO3 and cordierite phases, without segregation or formation of other oxides. After reduction, the LaCoO3 perovskite is transformed to metallic cobalt. The dip coating technique was efficient for deposition of the mixed oxide on the monolithic structure, without forming other structures. The adjustment of the zeta potential of the suspension was adequate to prevent agglomeration of the LaCoO3 particles. The catalysts were active for the POM reaction and were extremely stable during the tests. After reaction, RAMAN spectroscopy and SEM images revealed the presence of carbon nanotubes with large amount of defects at the surface. © 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

关键词： Hydrogen production

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Separation of Soybean Oil/n-hexane Miscellas Using Polymeric Membranes

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Journal of Food Science and engineering 2012年第11期2卷 616-624页

作者： Marcus V. Tres Jéssica C. Racoski Zuleica Novello Jonas R.M. de Melo Helen C. Ferraz Marco DiLuccio José Vladimir Oliveira: Department of Food Engineering URI-Campus de Erechim Av. Sete de Setembro 1621 Erechim 99700-000 RS Brazil Program of Chemical Engineering COPPE UFRJ-Centro de Tecnologia Bloco G Sala 115 Rio de Janeiro 21941-972 R JBrazil

Separation of refined soybean oil/n-hexane miscellas was studied using different commercial ultra- and nanofiltration membranes, with cut-oil＇s in the range of 1 to 5 kDa and salt rejection higher than 97% （MgSO4）. Commercial soybean oil and n-hexane miscellas with 1：3 and 1：1 mass ratios were permeated in a dead-end module. The effects of the feed pressure （2-25 bar） on oil and n-hexane fluxes and rejection were investigated. Oil rejection ranged from negative values to 30.8%, soybean oil flux from 28.9 to 617.8 g/m2 hl and n-hexane flux from 8.5 to 1,078.5 g m2 hl. Membrane fouling was observed at all experimental conditions studied. The membrane separation process has proven to be a promising alternative to solvent recovery in soybean oil extraction.

关键词： Soybean oil n-hexane ultrafiltration nanofiltration polymeric membranes.

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Overall efficiency evaluation of commercial distilattion column with two-pass valve trays

Overall efficiency evaluation of commercial distilattion col...

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2011 AIChE Spring Meeting and 7th Global Congress on Process Safety, 11AIChE

作者： Invernici, P.L. Secchi, A.R. Mendes, T.F. Basic Petrochemical Unit Braskem Triunfo RS Brazil Chemical Engineering Program COPPE UFRJ Rio de Janeiro RJ Brazil Department of Chemical Engineering UFRGS Porto Alegre RS Brazil

ISBN: (纸本)9780816910670

This article addresses the prediction of the efficiency of two-pass crossflow valve trays in an industrial distillation column using different models with and without the use of the Stagnant Regions Model, as proposed by Lockett in *** what could be expected, few papers have been published about the main characteristics of valve trays and about efficiency of two-pass valve trays. The results suggest that O'Connell's correlation, the model of Chan and Fair applied to two-pass valve trays converted to one-pass valve trays and the model of Chan and Fair with the SRM method are those that best predict the efficiency of this two-pass crossflow valve trays column. The O'Connell's correlation underestimates the efficiency, showing a slightly conservative value, while the predictions using Chan and Fair model and the modified Chan and Fair model with equivalent length proposed by Klemola and Ilme overestimate the efficiency, showing slightly non-conservative results.

关键词： Distillation columns

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Soft sensor models: Bias updating revisited

Soft sensor models: Bias updating revisited

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作者： Quelhas, André D. Pinto, José Carlos Petrobras - Corporate University Rio de Janeiro Brazil Chemical Engineering Program COPPE-UFRJ Rio de Janeiro Brazil

ISBN: (纸本)9783902661548

Bias updating is a widespread adaptive procedure to allow inference models to pursue time variant features of a real world process. The aim of this work is to clarify the statistical consequences of bias updating to soft sensor estimates as well to point up the need of careful analysis of the effect of unmeasured disturbances on the true values of the variable of interest. It is shown that bias updated inferences are unbiased estimates of the true value but yields estimates whose variance are 100% larger than the ones obtained with no use of bias updating. It is suggested the use of a weighting factor to bias updating in order to balance statistical benefits and penalties. A case study of a soft sensor for weathering of LPG in oil refinery exemplifies the concepts discussed.

关键词： Error statistics

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Soft sensor models: Bias updating revisited

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IFAC Proceedings Volumes 2009年第11期42卷 679-684页

作者： André D. Quelhas José Carlos Pinto Petrobras – Corporate University Rio de Janeiro - Brazil (Tel: +55-21-3487-3467 Chemical Engineering Program COPPE-UFRJ Rio de Janeiro - Brazil

Abstract Bias updating is a widespread adaptive procedure to allow inference models to pursue time variant features of a real world process. The aim of this work is to clarify the statistical consequences of bias updating to soft sensor estimates as well to point up the need of careful analysis of the effect of unmeasured disturbances on the true values of the variable of interest. It is shown that bias updated inferences are unbiased estimates of the true value but yields estimates whose variance are 100% larger than the ones obtained with no use of bias updating. It is suggested the use of a weighting factor to bias updating in order to balance statistical benefits and penalties. A case study of a soft sensor for weathering of LPG in oil refinery exemplifies the concepts discussed.

关键词： Soft sensor Bias Updating Error Analysis Statistics

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Preliminary results of Carbon Budget in two hydroelectric reservoirs in Brazil

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International Symposium on Dams in the Societies of the 21st Century, ICOLD-SPANCOLD - Dams and Reservoirs, Societies and Environment in the 21st Century

作者： Dos Santos, M.A. Matvienko, B. Pinguelli Rosa, L. Oliveira Dos Santos, E. Sikar, E. Eça D'Almeida Rocha, C.H. Santos Costa, R. Bento Silva, M. Rao Patchineelam, S. Portilho Bentes Jr., A.M. Energy Planning Program COPPE UFRJ Rio de Janeiro Brazil Unigranrio Rio de Janeiro Brazil Center of Applied Ecology and Hydraulics USP São Carlos Brazil Construmaq São Carlos São Carlos Brazil Civil Engineering Program COPPE UFRJ Rio de Janeiro Brazil Geochemical Department UFF Rio de Janeiro Brazil Chemistry of Chemical Engineering Program COPPE UFRJ Rio de Janeiro Brazil

ISBN: (纸本)0415404231

Pioneering studies were carried out in relation to greenhouse gas emissions from the conversion of forests and agricultural land to hydroelectric reservoirs and its relationship with greenhouse gas emissions. coppe/ufrj team has been carrying out several studies on greenhouse gases emissions by hydropower plants. This paper has been presented to show the preliminary results of two reservoirs studied by coppe/ufrj in the Carbon Budget Project of Furnas Centrais Elétricas S.A. This project has been developed to identify the carbon cycle pathways and related environmental aspects. The objective of coppe team in this project is measure flux estimates of CO2, CH4 e N2O in the water-atmosphere interface and water column as well as the determination of incoming carbon and sedimentation rates. Here the results of three field trips are presented for two reservoirs, Serra da Mesa and Manso. © 2006 Taylor & Francis Group.

关键词： Carbon

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CONTROLLING THE PERFORMANCE OF A CYCLONIC OIL-WATER SEPARATION SYSTEM

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IFAC Proceedings Volumes 2006年第2期39卷 391-396页

作者： Giovani Cavalcanti Nunes Magno Antonio Calil Enrique Luis Lima Research Centre of PETROBRAS-CENPES 22411.001-Rio de Janeiro-RJ-Brazil Chemical Engineering Program COPPE-UFRJ BOX 68502-21945.970- Rio de Janeiro-RJ-Brazil

This work analyzes various configurations for the control of a recently developed compact oil-water separation process for offshore production platforms consisting of a gravity separator and a sequence of three modules of hydrocyclones. Three different control algorithms were compared for interface level control in the separator: proportional and integral, band and linear model predictive control. These algorithms were combined with a classical differential pressure ratio (DPR) control for the modules of hydrocyclones. Results have shown that band control is a promising approach for the interface level and that the DPR control is better if only used in the last module of the sequence of hydrocyclones.

关键词： Process control control algorithms load regulation level control process models

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Preface: chemical engineering in Brazil: A growing presence in the country and in the world

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Brazilian Journal of chemical engineering 2003年第4期20卷 iii-v页

作者： Loureiro, Luiz Valcov Do Nascimento, Claudio Augusto Oller Nóbrega, Ronaldo Chemical Engineering Department University of São Paulo - USP São Paulo Brazil Grad. Program on Chemical Eng. COPPE Federal Univ. of Rio de Janeiro-UFRJ Rio de Janeiro Brazil

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