The Experts below are selected from a list of 165 Experts worldwide ranked by ideXlab platform
Eric Masanet - One of the best experts on this subject based on the ideXlab platform.
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energy efficiency improvement and cost saving opportunities for the pulp and paper industry
2011Co-Authors: Klaas Jan Kramer, Eric Masanet, Tengfang Xu, Ernst WorrellAbstract:The U.S. pulp and paper industry—defined in this Energy Guide as facilities engaged in the manufacture of pulp, paper, and paperboard—consumes over $7 billion worth of purchased fuels and electricity per year. Energy efficiency improvement is an important way to reduce these costs and to increase predictable earnings, especially in times of high energy price volatility. There are a variety of opportunities available at individual plants in the U.S. pulp and paper industry to reduce energy consumption in a cost-effective manner. This Energy Guide discusses energy efficiency practices and energy-efficient technologies that can be implemented at the component, Process, Facility, and organizational levels. This Energy Guide begins with an overview of the trends, structure, and energy consumption characteristics of the U.S. pulp and paper industry, along with descriptions of the major Process technologies used within the industry. Next, a wide variety of energy efficiency measures applicable to pulp and paper mills are described. Many measure descriptions include expected savings in energy and energy-related costs, which are based on case study data from real-world applications in pulp and paper mills and related industries worldwide. Typical measure payback periods and references to further information in the technical literature are also provided, when available. Given the importance of water use in pulp and paper mills, a summary of basic measures for improving plant-level water efficiency is also provided. The information in this Energy Guide is intended to help energy and plant managers in the U.S. pulp and paper industry reduce energy and water consumption in a cost-effective manner while maintaining the quality of products manufactured. Further research on the economics of all measures—as well as on their applicability to different production practices—is needed to assess their cost effectiveness at individual plants.
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energy efficiency opportunities in the u s pulp and paper industry
Energy Engineering, 2010Co-Authors: Klaas Jan Kramer, Eric Masanet, Ernst WorrellAbstract:The U.S. pulp and paper industry consumes over $7 billion worth of purchased fuels and electricity per year. Energy efficiency improvement is an important way to reduce these costs and to increase predictable earnings, especially in times of high energy price volatility. There are a variety of opportunities available at individual plants in the U.S. pulp and paper industry to reduce energy consumption in a cost-effective manner. This paper provides a brief overview of the U.S. EPA ENERGY STAR(R) for Industry energy efficiency guidebook (a.k.a. the Energy Guide ) for pulp and paper manufacturers. The Energy Guide discusses a wide range of energy efficiency practices and energy-efficient technologies that can be implemented at the component, Process, Facility, and organizational levels. Also provided is a discussion of the trends, structure, and energy consumption characteristics of the U.S. pulp and paper industry along with a description of the major Process technologies used within the industry. Many energy efficiency measure descriptions include expected savings in energy and energy-related costs, based on case study data from real-world applications in pulp and paper mills and related industries worldwide. The information in this Energy Guide is intended to help energy and plant managers in the U.S. pulp and paper industry reduce energy consumption in a cost-effective manner while maintaining the quality of products manufactured. Further research on the economics of all measures?as well as on their applicability to different production practices?is needed to assess their cost effectiveness at individual plants.
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energy efficiency improvement and cost saving opportunities for the pulp and paper industry an energy star guide for energy and plant managers
2009Co-Authors: Klaas Jan Kramer, Ernst Worrell, Eric Masanet, Tengfang XuAbstract:The U.S. pulp and paper industry—defined in this Energy Guide as facilities engaged in the manufacture of pulp, paper, and paperboard—consumes over $7 billion (48 billion yuan or RMB) worth of purchased fuels and electricity per year. Energy efficiency improvement is an important way to reduce these costs and to increase predictable earnings, especially in times of high energy price volatility. There are a variety of opportunities available at individual plants in the U.S. pulp and paper industry to reduce energy consumption in a cost-effective manner. This Energy Guide discusses energy efficiency practices and energy-efficient technologies that can be implemented at the component, Process, Facility, and organizational levels. This Energy Guide begins with an overview of the trends, structure, and energy consumption characteristics of the U.S. pulp and paper industry, along with descriptions of the major Process technologies used within the industry. Next, a wide variety of energy efficiency measures applicable to pulp and paper mills are described. Many measure descriptions include expected savings in energy and energy-related costs, which are based on case study data from real-world applications in pulp and paper mills and related industries worldwide. Typical measure payback periods and references to further information in the technical literature are also provided, when available. Given the importance of water use in pulp and paper mills, a summary of basic measures for improving plant-level water efficiency is also provided. The information in this Energy Guide is intended to help energy and plant managers in the U.S. pulp and paper industry reduce energy and water consumption in a cost-effective manner while maintaining the quality of products manufactured. Further research on the economics of all measures—as well as on their applicability to different production practices—is needed to assess their cost effectiveness at individual plants.
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energy efficiency improvement and cost saving opportunities for the petrochemical industry an energy star r guide for energy and plant managers
Lawrence Berkeley National Laboratory, 2008Co-Authors: Maarten Neelis, Ernst Worrell, Eric MasanetAbstract:Energy is the most important cost factor in the U.S petrochemical industry, defined in this guide as the chemical industry sectors producing large volume basic and intermediate organic chemicals as well as large volume plastics. The sector spent about $10 billion on fuels and electricity in 2004. Energy efficiency improvement is an important way to reduce these costs and to increase predictable earnings, especially in times of high energy price volatility. There are a variety of opportunities available at individual plants in the U.S. petrochemical industry to reduce energy consumption in a cost-effective manner. This Energy Guide discusses energy efficiency practices and energy efficient technologies that can be implemented at the component, Process, Facility, and organizational levels. A discussion of the trends, structure, and energy consumption characteristics of the petrochemical industry is provided along with a description of the major Process technologies used within the industry. Next, a wide variety of energy efficiency measures are described. Many measure descriptions include expected savings in energy and energy-related costs, based on case study data from real-world applications in the petrochemical and related industries worldwide. Typical measure payback periods and references to further information in the technical literature are also provided, when available. The information in this Energy Guide is intended to help energy and plant managers in the U.S. petrochemical industry reduce energy consumption in a cost-effective manner while maintaining the quality of products manufactured. Further research on the economics of all measures--and on their applicability to different production practices--is needed to assess their cost effectiveness at individual plants.
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Energy Efficiency Improvement and Cost Saving Opportunities for the Fruit and Vegetable Processing Industry. An ENERGY STAR Guide for Energy and Plant Managers
Lawrence Berkeley National Laboratory, 2008Co-Authors: Eric Masanet, Ernst Worrell, Wina Graus, Christina GalitskyAbstract:The U.S. fruit and vegetable Processing industry--defined in this Energy Guide as facilities engaged in the canning, freezing, and drying or dehydrating of fruits and vegetables--consumes over $800 million worth of purchased fuels and electricity per year. Energy efficiency improvement is an important way to reduce these costs and to increase predictable earnings, especially in times of high energy price volatility. There are a variety of opportunities available at individual plants in the U.S. fruit and vegetable Processing industry to reduce energy consumption in a cost-effective manner. This Energy Guide discusses energy efficiency practices and energy-efficient technologies that can be implemented at the component, Process, Facility, and organizational levels. A discussion of the trends, structure, and energy consumption characteristics of the U.S. fruit and vegetable Processing industry is provided along with a description of the major Process technologies used within the industry. Next, a wide variety of energy efficiency measures applicable to fruit and vegetable Processing plants are described. Many measure descriptions include expected savings in energy and energy-related costs, based on case study data from real-world applications in fruit and vegetable Processing facilities and related industries worldwide. Typical measure payback periods and references to further information in the technical literature are also provided, when available. Given the importance of water in fruit and vegetable Processing, a summary of basic, proven measures for improving plant-level water efficiency are also provided. The information in this Energy Guide is intended to help energy and plant managers in the U.S. fruit and vegetable Processing industry reduce energy and water consumption in a cost-effective manner while maintaining the quality of products manufactured. Further research on the economics of all measures--as well as on their applicability to different production practices--is needed to assess their cost effectiveness at individual plants.
Ernst Worrell - One of the best experts on this subject based on the ideXlab platform.
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energy efficiency improvement and cost saving opportunities for the pulp and paper industry
2011Co-Authors: Klaas Jan Kramer, Eric Masanet, Tengfang Xu, Ernst WorrellAbstract:The U.S. pulp and paper industry—defined in this Energy Guide as facilities engaged in the manufacture of pulp, paper, and paperboard—consumes over $7 billion worth of purchased fuels and electricity per year. Energy efficiency improvement is an important way to reduce these costs and to increase predictable earnings, especially in times of high energy price volatility. There are a variety of opportunities available at individual plants in the U.S. pulp and paper industry to reduce energy consumption in a cost-effective manner. This Energy Guide discusses energy efficiency practices and energy-efficient technologies that can be implemented at the component, Process, Facility, and organizational levels. This Energy Guide begins with an overview of the trends, structure, and energy consumption characteristics of the U.S. pulp and paper industry, along with descriptions of the major Process technologies used within the industry. Next, a wide variety of energy efficiency measures applicable to pulp and paper mills are described. Many measure descriptions include expected savings in energy and energy-related costs, which are based on case study data from real-world applications in pulp and paper mills and related industries worldwide. Typical measure payback periods and references to further information in the technical literature are also provided, when available. Given the importance of water use in pulp and paper mills, a summary of basic measures for improving plant-level water efficiency is also provided. The information in this Energy Guide is intended to help energy and plant managers in the U.S. pulp and paper industry reduce energy and water consumption in a cost-effective manner while maintaining the quality of products manufactured. Further research on the economics of all measures—as well as on their applicability to different production practices—is needed to assess their cost effectiveness at individual plants.
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energy efficiency opportunities in the u s pulp and paper industry
Energy Engineering, 2010Co-Authors: Klaas Jan Kramer, Eric Masanet, Ernst WorrellAbstract:The U.S. pulp and paper industry consumes over $7 billion worth of purchased fuels and electricity per year. Energy efficiency improvement is an important way to reduce these costs and to increase predictable earnings, especially in times of high energy price volatility. There are a variety of opportunities available at individual plants in the U.S. pulp and paper industry to reduce energy consumption in a cost-effective manner. This paper provides a brief overview of the U.S. EPA ENERGY STAR(R) for Industry energy efficiency guidebook (a.k.a. the Energy Guide ) for pulp and paper manufacturers. The Energy Guide discusses a wide range of energy efficiency practices and energy-efficient technologies that can be implemented at the component, Process, Facility, and organizational levels. Also provided is a discussion of the trends, structure, and energy consumption characteristics of the U.S. pulp and paper industry along with a description of the major Process technologies used within the industry. Many energy efficiency measure descriptions include expected savings in energy and energy-related costs, based on case study data from real-world applications in pulp and paper mills and related industries worldwide. The information in this Energy Guide is intended to help energy and plant managers in the U.S. pulp and paper industry reduce energy consumption in a cost-effective manner while maintaining the quality of products manufactured. Further research on the economics of all measures?as well as on their applicability to different production practices?is needed to assess their cost effectiveness at individual plants.
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energy efficiency improvement and cost saving opportunities for the pulp and paper industry an energy star guide for energy and plant managers
2009Co-Authors: Klaas Jan Kramer, Ernst Worrell, Eric Masanet, Tengfang XuAbstract:The U.S. pulp and paper industry—defined in this Energy Guide as facilities engaged in the manufacture of pulp, paper, and paperboard—consumes over $7 billion (48 billion yuan or RMB) worth of purchased fuels and electricity per year. Energy efficiency improvement is an important way to reduce these costs and to increase predictable earnings, especially in times of high energy price volatility. There are a variety of opportunities available at individual plants in the U.S. pulp and paper industry to reduce energy consumption in a cost-effective manner. This Energy Guide discusses energy efficiency practices and energy-efficient technologies that can be implemented at the component, Process, Facility, and organizational levels. This Energy Guide begins with an overview of the trends, structure, and energy consumption characteristics of the U.S. pulp and paper industry, along with descriptions of the major Process technologies used within the industry. Next, a wide variety of energy efficiency measures applicable to pulp and paper mills are described. Many measure descriptions include expected savings in energy and energy-related costs, which are based on case study data from real-world applications in pulp and paper mills and related industries worldwide. Typical measure payback periods and references to further information in the technical literature are also provided, when available. Given the importance of water use in pulp and paper mills, a summary of basic measures for improving plant-level water efficiency is also provided. The information in this Energy Guide is intended to help energy and plant managers in the U.S. pulp and paper industry reduce energy and water consumption in a cost-effective manner while maintaining the quality of products manufactured. Further research on the economics of all measures—as well as on their applicability to different production practices—is needed to assess their cost effectiveness at individual plants.
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energy efficiency improvement and cost saving opportunities for the petrochemical industry an energy star r guide for energy and plant managers
Lawrence Berkeley National Laboratory, 2008Co-Authors: Maarten Neelis, Ernst Worrell, Eric MasanetAbstract:Energy is the most important cost factor in the U.S petrochemical industry, defined in this guide as the chemical industry sectors producing large volume basic and intermediate organic chemicals as well as large volume plastics. The sector spent about $10 billion on fuels and electricity in 2004. Energy efficiency improvement is an important way to reduce these costs and to increase predictable earnings, especially in times of high energy price volatility. There are a variety of opportunities available at individual plants in the U.S. petrochemical industry to reduce energy consumption in a cost-effective manner. This Energy Guide discusses energy efficiency practices and energy efficient technologies that can be implemented at the component, Process, Facility, and organizational levels. A discussion of the trends, structure, and energy consumption characteristics of the petrochemical industry is provided along with a description of the major Process technologies used within the industry. Next, a wide variety of energy efficiency measures are described. Many measure descriptions include expected savings in energy and energy-related costs, based on case study data from real-world applications in the petrochemical and related industries worldwide. Typical measure payback periods and references to further information in the technical literature are also provided, when available. The information in this Energy Guide is intended to help energy and plant managers in the U.S. petrochemical industry reduce energy consumption in a cost-effective manner while maintaining the quality of products manufactured. Further research on the economics of all measures--and on their applicability to different production practices--is needed to assess their cost effectiveness at individual plants.
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Energy Efficiency Improvement and Cost Saving Opportunities for the Fruit and Vegetable Processing Industry. An ENERGY STAR Guide for Energy and Plant Managers
Lawrence Berkeley National Laboratory, 2008Co-Authors: Eric Masanet, Ernst Worrell, Wina Graus, Christina GalitskyAbstract:The U.S. fruit and vegetable Processing industry--defined in this Energy Guide as facilities engaged in the canning, freezing, and drying or dehydrating of fruits and vegetables--consumes over $800 million worth of purchased fuels and electricity per year. Energy efficiency improvement is an important way to reduce these costs and to increase predictable earnings, especially in times of high energy price volatility. There are a variety of opportunities available at individual plants in the U.S. fruit and vegetable Processing industry to reduce energy consumption in a cost-effective manner. This Energy Guide discusses energy efficiency practices and energy-efficient technologies that can be implemented at the component, Process, Facility, and organizational levels. A discussion of the trends, structure, and energy consumption characteristics of the U.S. fruit and vegetable Processing industry is provided along with a description of the major Process technologies used within the industry. Next, a wide variety of energy efficiency measures applicable to fruit and vegetable Processing plants are described. Many measure descriptions include expected savings in energy and energy-related costs, based on case study data from real-world applications in fruit and vegetable Processing facilities and related industries worldwide. Typical measure payback periods and references to further information in the technical literature are also provided, when available. Given the importance of water in fruit and vegetable Processing, a summary of basic, proven measures for improving plant-level water efficiency are also provided. The information in this Energy Guide is intended to help energy and plant managers in the U.S. fruit and vegetable Processing industry reduce energy and water consumption in a cost-effective manner while maintaining the quality of products manufactured. Further research on the economics of all measures--as well as on their applicability to different production practices--is needed to assess their cost effectiveness at individual plants.
K.j. Imrich - One of the best experts on this subject based on the ideXlab platform.
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degradation of a n06690 borescope in a radioactive waste glass melter system
2. international conference on heat resistant materials Gatlinburg TN (United States) 11-14 Sep 1995, 1995Co-Authors: K.j. ImrichAbstract:Radioactive liquid waste from nuclear materials production Processes wi11 be vitrified in the Defense Waste Process Facility (DWPF) melter. The melter borescope outer housing, fabricated from N06690, was severely degraded by the combined effects of corrosion and oxidation after only five months of non radioactive operation. The melter was idled and not being fed over 85% of the time during the cold run operations. The borescope was designed to perform in an oxygen rich, chloride containing environment with temperatures approaching 900{degree}C (1650{degree}F). The housing was designed for a minimum of two years of continuous service in the DWPF melter. Air and steam were purged through the borescope and swept over the optics assembly to keep molten glass and volatile gases from depositing on the lens cover. Upon exiting the borescope the air passes through a N06690 orifice and enters the melter. Severe oxidation was observed around the orifice. Extensive material loss was also observed on the side of the outer housing which protrudes through the dome of the melter. Redesign of the borescope is currently underway and will include a new set of optics that will allow the size of the orifice to be significantly decreased, thus reducing the amount of air necessary to keep the lens cover clean. Application of a duplex diffusion coating, consisting of chromium and aluminum, on the end of the borescope outer housing and the use of an inert gas purge are also being considered.
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Degradation of a N06690 borescope in a radioactive waste/glass melter system
1995Co-Authors: K.j. ImrichAbstract:Radioactive liquid waste from nuclear materials production Processes wi11 be vitrified in the Defense Waste Process Facility (DWPF) melter. The melter borescope outer housing, fabricated from N06690, was severely degraded by the combined effects of corrosion and oxidation after only five months of non radioactive operation. The melter was idled and not being fed over 85% of the time during the cold run operations. The borescope was designed to perform in an oxygen rich, chloride containing environment with temperatures approaching 900{degree}C (1650{degree}F). The housing was designed for a minimum of two years of continuous service in the DWPF melter. Air and steam were purged through the borescope and swept over the optics assembly to keep molten glass and volatile gases from depositing on the lens cover. Upon exiting the borescope the air passes through a N06690 orifice and enters the melter. Severe oxidation was observed around the orifice. Extensive material loss was also observed on the side of the outer housing which protrudes through the dome of the melter. Redesign of the borescope is currently underway and will include a new set of optics that will allow the size of the orifice to be significantly decreased, thus reducing the amount of air necessary to keep the lens cover clean. Application of a duplex diffusion coating, consisting of chromium and aluminum, on the end of the borescope outer housing and the use of an inert gas purge are also being considered.
Faisal Khan - One of the best experts on this subject based on the ideXlab platform.
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a novel Process economics risk model applied to biodiesel production system
Renewable Energy, 2018Co-Authors: Zaman Sajid, Faisal Khan, Yan ZhangAbstract:Abstract In this paper, the concept of value at risk (VAR) is introduced to study Process economics related to biodiesel production and use. Although the VAR concept is actively used in financial engineering for stock investment and trading, it has never been used in Process economics. A methodology to develop a VAR model for a biodiesel Process Facility has been proposed and analysed. The impact of different cost related risk factors is modelled using a stochastic Process and interdependence in a Bayesian Network format. The analysis reveals that cost underestimation is the most significant risk factor in biodiesel economics. The VAR model is analysed for 1, 5, and 10 VAR for 5 years of plant operations. Analysing VAR at any point of time (i.e. year 2) shows that with a 1% chance, 5% chance and 10% chance, the maximum loss would be $6.26, $9.52 and $11.34 million respectively (up to year 2). When VAR is considered in the Process economics the return period is significantly affected and is increased by 21 months. This study recommends that VAR should be considered as an integral part of Process economics, especially for new product or Process design.
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Industry specific dust explosion likelihood assessment model with case studies
Journal of Chemical Health and Safety, 2014Co-Authors: Junaid Hassan, Paul Amyotte, Faisal Khan, Refaul FerdousAbstract:Dust explosion is a potential threat to the Process facilities handling dusts. Dust explosion occurrences are frequently reported in these industries. Industrial professionals and researchers have been trying to develop effective measures to assess and mitigate and/or prevent dust explosion. To develop effective prevention and mitigation strategies, it is important to understand the interaction of dust explosion controlling parameters and also to assess likelihood of occurrence in given conditions. Authors have proposed a conceptual framework to model dust explosion likelihood. In this paper, a detailed implementation of the conceptual model is presented. Three different dust classes (i.e. food feed; plastic, resin and rubber; and metal alloys) are considered for model development. The proposed model considers six key parameters of dust explosion: dust particles diameter, minimum ignition energy, minimum explosible concentration, minimum ignition temperature, limiting oxygen concentration and explosion pressure. These parameters are conditional to the type of dust and chemical composition. A conditional probabilistic approach is used to determine the total probability of dust explosion in a given Process Facility. Use of this model will help to assess the likelihood of dust explosion in given operating conditions. Moreover, it will help to develop prevention strategies focusing on the parameters that are responsible for dust explosion. Three case studies are presented here to demonstrate the application of the model in real life.
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the role of human error in risk analysis application to pre and post maintenance procedures of Process facilities
Reliability Engineering & System Safety, 2013Co-Authors: Alireza Noroozi, Faisal Khan, Nima Khakzad, Scott Mackinnon, Rouzbeh AbbassiAbstract:Human factors play an important role in the safe operation of a Facility. Human factors include the systematic application of information about human characteristics and behavior to increase the safety of a Process system. A significant proportion of human errors occur during the maintenance phase. However, the quantification of human error probabilities in the maintenance phase has not been given the amount of attention it deserves. This paper focuses on a human factors analysis in pre-and post- pump maintenance operations. The procedures for removing Process equipment from service (pre-maintenance) and returning the equipment to service (post-maintenance) are considered for possible failure scenarios. For each scenario, human error probability is calculated for each activity using the Success Likelihood Index Method (SLIM). Consequences are also assessed in this methodology. The risk assessment is conducted for each component and the overall risk is estimated by adding individual risks. The present study is aimed at highlighting the importance of considering human error in quantitative risk analyses. The developed methodology has been applied to a case study of an offshore Process Facility.
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shipp methodology predictive accident modeling approach part ii validation with case study
Process Safety and Environmental Protection, 2011Co-Authors: Samith Rathnayaka, Faisal Khan, Paul AmyotteAbstract:Abstract System Hazard Identification, Prediction and Prevention (SHIPP) is a systematic methodology to identify, evaluate, and model the accident Process, thereby predicting and preventing future accidents in a Process Facility. In this methodology, Process hazard accidents are modeled using safety barriers rather than causal factors. The fault tree and event tree analysis techniques enhance the accident model to represent a holistic picture of the cause-consequence mechanism of the accident Process. Quantitative analysis has two aspects: updating and prediction. The Bayesian theory updates failure probability and consequence occurrence probability when a new observation arrives. The predictive model forecasts the probability of a number of abnormal events occurring in the next time interval. The qualitative and quantitative capabilities of the SHIPP methodology help to design and implement safety strategies into a Process system. This methodology was presented in Part I of a series of two papers. This paper (Part II) presents the results of a case study carried out on a liquefied natural gas (LNG) Facility. It is conducted with the sole purpose of testing the SHIPP methodology. Gas production and liquefaction were considered as a boundary for accident analysis. This paper illustrates accident model development and cause-consequence analysis for the LNG Facility. The updated results demonstrate that the probabilities of abnormal events dramatically change over time as new information is observed. Using accident precursor data for the year 2009, the predictive model estimates that the mean of abnormal events occurring in the next time interval is 22. The qualitative and quantitative analyses provide insight to identify critical safety areas and functions, and to determine the likelihood of failure of these measures. Combining management oversight and engineering analyses, the SHIPP methodology provides a comprehensive, systematic approach to manage a system risk.
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methodology for computer aided fuzzy fault tree analysis
Process Safety and Environmental Protection, 2009Co-Authors: Refaul Ferdous, Faisal Khan, Brian Veitch, Paul AmyotteAbstract:Process facilities are well known for unplanned chemical emission, toxic release, fire and explosion and operational disruption. These incidents have the potential to cause an industrial accident and environmental damage. From the investigation of all major accidents, it is apparent that most industrial accidents can be avoided or restricted with a systematic risk analysis and safety management strategy. An effective risk analysis strategy always gives preference to minimizing the risk of a Process Facility at its design stages. -- Probabilistic risk assessment (PRA) is a comprehensive, structured and logical method for identifying and assessing risks of complex Process systems. It uses fault tree analysis (FTA) as a tool to identify basic causes leading to an undesired event, to represent logical dependency of these basic causes in leading to the event, and finally to calculate the probability of occurrence of this event. Probability data estimation, and large and complex fault trees, are challenging aspects of FTA as applied to Process facilities. -- Quantitative analysis of a fault tree for a Process system requires a fault tree and the system components (basic events) failure data. Sometimes or always it is difficult to have an exact estimation of the failure rate of individual components or the probability of occurrence of undesired events due to a lack of sufficient data. Further, due to imprecision in basic failure data or the data sufficiency the overall analysis of a fault tree may be questionable. To avoid such conditions, a fuzzy approach may be used with the FTA technique. This reduces the ambiguity and imprecision arising out of the subjectivity of the data. -- Fault tree construction for a Process Facility must accommodate for a wide variation in components, Process operations and control mechanisms. It is more scientific to analyze such a large and complex fault tree through proper sub-divisions of the tree. A proper modularization technique (sub-division) can sub divide a tree into its equivalent sub trees and then analyze it for the Process Facility. -- This work is focused on developing a methodology of a fuzzy based computer-aided fault tree analysis tool. The central idea of this methodology is to adopt a suitable algorithm for moduling (sub-dividing) a large and complex fault tree and then evaluate it by using the fuzzy approach. This methodology uses a systematic approach of fault tree development, fault tree modularization, minimal cut sets determination, fuzzy probability analysis, and fuzzy based sensitivity analysis of a system for achieving its objectives. Besides developing a methodology for computer- aided FTA, this study also proposes a procedure of fuzzy approach for the uncertainty analysis, which is used for comparing error robustness of fuzzy FTA and conventional FTA.
Juan Jose Villaverde Mella - One of the best experts on this subject based on the ideXlab platform.
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miscanthus x giganteus a source of biobased products characterizacion organosolv fractionation and tcf bleaching
2009Co-Authors: Juan Jose Villaverde MellaAbstract:Many national governments worldwide have already perceived the importance of biomass in a model of sustainable socio-economic development. For this reason, its use is being stimulated and a wide variety of bioproducts, bioenergy and biofuels are being introduced in markets competing with oil-based products for quality, prices and consumers interest. A biorefinery is a Process Facility that integrates biomass conversion Processes and equipment to produce fuels, power, and chemicals from biomass. The achievement of replacing petroleum- for bio-based products will mean a great challenge and aspects like adequate selection of plant species, productivity increase with a rational use of soil, fertilizers, pesticides and water, the use of genetically modified organisms and logistics, among others, will have to be directed. Furthermore, it will be essential that biobased products do not come from part of the food production, particularly when the world population is expected to reach 9-10 billion by the middle of the XXI century. In this complex scenario, a deep knowledge and thorough understanding of the composition of each plant species and the development of efficient Processing and chemical/biochemical transformation/fractionation technologies will be essential for the development of future biorefineries. The main objective of this work was to evaluate the potential of Miscanthus x giganteus as a source of organic chemicals for Processes in biorefineries. In order to achieve this, lipophilic extractives obtained from bark and core, were analyzed by gas chromatography-mass spectrometry (GC-MS), showing that several compounds with useful nutraceutical and pharmacological applications (sterols and aromatic compounds) are abundant especially in the core extractives and that they could be a source of added value in a future biorefinery, using this species as raw material. Optimization studies were carried out on two organosolv fractionation Processes, viz., Acetosolv and Formosolv, and evaluated with the help of appropriate kinetic models, achieving suitable pulps to initiate a bleaching Process (with kappa numbers near 20). Besides, the lignins from black liquors were isolated, purified and characterized. The physico-chemical changes with respect to milled wood lignin (MWL) were analyzed using analytical techniques such as nuclear magnetic resonance (NMR), size-exclusion chromatography (SEC) and thioacidolysis, observing that these lignins are probably acylated at the carbon of the side-chain. The influence of the main operational variables in the bleaching of M. x giganteus Acetosolv pulps with hydrogen peroxide/acetic acid (in aqueous alkaline media and in acetic acid media) was also evaluated, using factorial designs of experiments, and pulps fulfil the requirements for forthcoming stages. This methodology was also used to optimize the bleaching of Acetosolv pulps, with a new sequence free of chlorine [EPabO(PO)P], introducing peroxyacetate ion as bleaching species (Pab-stage). The sequence was tested with Formosolv and Milox pulps (brightnesses near 90% ISO were obtained with good intrinsic viscosities). The necessity of carbohydrate protectors was analyzed: no beneficial effect was observed until the last two stages, where addition of DTPA and MgSO4 preserved the cellulose chains.
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miscanthus x giganteus a source of biobased products characterizacion organosolv fractionation and tcf bleaching
2009Co-Authors: Juan Jose Villaverde MellaAbstract:Many national governments worldwide have already perceived the importance of biomass in a model of sustainable socio-economic development. For this reason, its use is being stimulated and a wide variety of bioproducts, bioenergy and biofuels are being introduced in markets competing with oil-based products for quality, prices and consumers interest. A biorefinery is a Process Facility that integrates biomass conversion Processes and equipment to produce fuels, power, and chemicals from biomass. The achievement of replacing petroleum- for bio-based products will mean a great challenge and aspects like adequate selection of plant species, productivity increase with a rational use of soil, fertilizers, pesticides and water, the use of genetically modified organisms and logistics, among others, will have to be directed. Furthermore, it will be essential that biobased products do not come from part of the food production, particularly when the world population is expected to reach 9-10 billion by the middle of the XXI century. In this complex scenario, a deep knowledge and thorough understanding of the composition of each plant species and the development of efficient Processing and chemical/biochemical transformation/fractionation technologies will be essential for the development of future biorefineries. The main objective of this work was to evaluate the potential of Miscanthus x giganteus as a source of organic chemicals for Processes in biorefineries. In order to achieve this, lipophilic extractives obtained from bark and core, were analyzed by gas chromatography-mass spectrometry (GC-MS), showing that several compounds with useful nutraceutical and pharmacological applications (sterols and aromatic compounds) are abundant especially in the core extractives and that they could be a source of added value in a future biorefinery, using this species as raw material. Optimization studies were carried out on two organosolv fractionation Processes, viz., Acetosolv and Formosolv, and evaluated with the help of appropriate kinetic models, achieving suitable pulps to initiate a bleaching Process (with kappa numbers near 20). Besides, the lignins from black liquors were isolated, purified and characterized. The physico-chemical changes with respect to milled wood lignin (MWL) were analyzed using analytical techniques such as nuclear magnetic resonance (NMR), size-exclusion chromatography (SEC) and thioacidolysis, observing that these lignins are probably acylated at the carbon of the side-chain. The influence of the main operational variables in the bleaching of M. x giganteus Acetosolv pulps with hydrogen peroxide/acetic acid (in aqueous alkaline media and in acetic acid media) was also evaluated, using factorial designs of experiments, and pulps fulfil the requirements for forthcoming stages. This methodology was also used to optimize the bleaching of Acetosolv pulps, with a new sequence free of chlorine [EPabO(PO)P], introducing peroxyacetate ion as bleaching species (Pab-stage). The sequence was tested with Formosolv and Milox pulps (brightnesses near 90% ISO were obtained with good intrinsic viscosities). The necessity of carbohydrate protectors was analyzed: no beneficial effect was observed until the last two stages, where addition of DTPA and MgSO4 preserved the cellulose chains.