bluuebunny/crossref_metadata_2025_split huggingface dataset:
Emergency relief system (ERS) design: An integrated approach using DIERS methodology
Authors: Biocourt Gerald W. 
Published: June 2004

AbstractThe Design Institute for Emergency Relief Systems (DIERS) has developed methodologies for sizing relief devices for two‐phase flow. Good engineering practices which account for two‐phase flow will ensure against undersized relief devices and potentially catastrophic vessel overpressurization. Application of the DIERS tools and methodologies for two‐phase flow can be a formidable undertaking for the uninitiated. This paper attempts to mitigate some of the complexities by a discussion of tempered systems in an integrated form. Tempered, gassy and hybrid systems are identified. Both reactive and non‐reactive systems will be considered. The integrated relief system consists of the reactor, relief device, and vent line. The design equations are presented with their underlying assumptions and application limitations. The importance of experimental design data is stressed. The “omega” methodology is discussed with examples.
Take chemistry and physics into consideration in all phases of chemical plant design
Authors: Lutz William K. 
Published: June 2004

AbstractAccurate description of chemical and physical properties form the basis of chemical research, development, and commercialization of chemistry into products. The operating conditions for the chemical process are usually quite specific and are the focus of the entire commercialization activity. With the commitment to protect the worker, the public, and the environment, new or refined methods may be needed to control chemical and physical phenomena that can occur at the extreme bounds of the processing conditions. This control is accomplished in a variety of ways, but is usually done by providing a mix of passive, active and procedural controls.Those with safety and risk assessment responsibilities in the Chemical Process Industry (CPI) identify hazards and assess risks inside these operating conditions and work diligently with their respective chemical development Teams to define the phenomena that can occur at the full operating capability of the commercial equipment. Phenomena like loss of thermal stability, and side reactions that do not occur within the desired operating conditions, may be enabled when the chemical processing conditions proceed toward the design limits of the equipment once control is lost.
Method used to estimate screening‐level total failure probability for human error events
Authors: Burns R. S. , Turner J. H. 
Published: June 2004

AbstractThis document briefly describes the method used to estimate a screening value for the Total Failure Probability (FT) of human error events that are identified in the fault trees which describe potential liquid UF6 release accidents at two U.S. Gaseous Diffusion Plants. A discussion is provided of the assumptions, limitations, and overall logic of the FT assignment method, and a description is presented of how the method is employed. The description herein, and more completely in Burns and Turner [1], presents the screening technique* used to quantify human errors in the accident analysis portion of the Gaseous Diffusion Plant Safety Analysis Report Upgrade Program.
Some thoughts on the difference between inherent safety and safety
Authors: Hendershot Dennis C. 
Published: June 2004

AbstractInherently safer processes represent the most desirable way to manage risk. However, we must not forget that other approaches can be used effectively, and the inherently hazardous processes can be operated safely. The overall benefits of a hazardous technology can justify the use of that technology, with appropriate resources devoted to risk management, as we continue to search for viable inherently safety alternatives.
Inherently safer design: The growth of an idea
Authors: Kletz Trevor A. 
Published: June 2004

AbstractInherently safer design, that is, avoiding hazards rather than controlling them, has advocated since the explosion at Flixborough in 1974. Progress has been real but nevertheless the concept has not been adopted nearly as rapidly as quantitative risk assessment, introduced into the chemical industry only a few years earlier. The present position is reviewed and the constraints that have to be overcome are outlined.A man takes a mustard seed and sows it in his field. It is the smallest of all seeds, but when it grows up, it is the biggest of all plants. It becomes a tree…—Matthew 13:31–32It takes longer to familiarize oneself with a region of the mind than with a country…—Graham Greene (Introduction to Brighton Rock)
Inherently safer latex plants
Authors: Scheffler Norman E. 
Published: June 2004

AbstractMajor improvements have occurred in the technology for making latex. Latex plants represent good examples of the application of inherently safer plant features. Early plants had Fire & Explosion Indexes (F&EIs) in a range of 159‐171 (Severe) whereas recent plants are in a range of 97–127 (Intermediate). A key design feature is adequate spacing. Minimum inventories of hazardous materials are maintained. Containment of hazardous materials minimizes exposure to facilities and people and provides adequate volume.Process structures are open to avoid accumulation of flammable gases. Containment in vessels uses high design pressures. Safe emergency relief venting is provided. The ability to make discrete batches is maintained, but some semi‐continuous feeding is used. Appropriate redundancy of instrument and control systems is used with sophisticated process control systems. Emergency block valves and fire tested valves are used. Inherently unsafe equipment is avoided. Good operating practices are employed with documentation of operation procedures, testing, maintenance and training. Fire protection systems and emergency planning are provided.The final result in applying inherently safer design practices is major improvement in safety and minimization of the risk potential for losses that could affect people, plant equipment, business loss and the environment.
The effects of downsizing on safety in the CPI/HPI
Authors: Perron Mlchael J. , Friedlander Randal H. 
Published: June 2004

AbstractA number of incidents including observations that underline the dangers of “starving” a safety program are discussed. While accurate data on the impact of substantial staff reductions remains scarce, many people in industry fear that excessive cutbacks could create conditions leading to a catastrophic accident. Guidelines are provided to assist management in evaluating manpower needs for successful management systems for Process Safety Management (PSM).
Hazopexpert: An expert system for automating HAZOP analysis
Authors: Vaidhyanathan Ramesh , Venkatasubramanian Venkat , Dyke Frederick T. 
Published: June 2004

AbstractHazard and operability (HAZOP) analysis is the study of systematically identifying every conceivable deviation from the design intent, and all possible abnormal causes, and adverse hazardous consequences that can occur in a chemical plant. This is a difficult, labor‐ and knowledge‐intensive, and time‐consuming analysis. HAZOP analysis is typically performed by a group of experts poring over the process P&IDs for weeks. An intelligent system for automating this analysis can reduce the time and effort involved, make the analysis more thorough and detailed, and minimize or eliminate possible human errors. Towards that goal, a model‐based framework has been developed in which the knowledge required to perform HAZOP analysis is divided into process‐specific and process‐general components. The process‐specific knowledge consists of the process material properties and the process P&ID. The process‐general knowledge consists of the HAZOP‐Digraph models of the process units which are qualitative causal models developed specifically for hazard identification. These models are developed in a context independent manner so that they can be used in a wide variety of processes. An inference mechanism is developed for appropriate interaction between these components in order to identify process‐specific abnormal causes and adverse consequences. Based on this framework, an expert system called HAZOPExpert has been developed in an object‐oriented architecture using the expert system shell G2. The salient features of the HAZOPExpert system and its performance on an industrial‐scale sour water stripper plant case study are presented.
A team‐based approach to mechanical integrity implementation
Authors: Herrington Edwin F. 
Published: June 2004

AbstractThe U.S. Occupational Safety and Health Administration (OSHA) promulgated the Process Safety Management of Highly Hazardous Chemicals standard (29CFR 1910.119) in 1992. One key provision of the regulation calls for a Mechanical Integrity (MI) program to ensure that process equipment containing and controlling highly hazardous chemicals is maintained to high standards, standards which minimize the chances of accidental release and subsequent injuries or incidents. This article addresses the approach taken by Tennessee Eastman Division in the implementation of the OSHA MI requirements.
Testing the suitability of FIBCs for use in flammable atmospheres
Authors: Ebadat Vahid , Mulligan James C. 
Published: June 2004

AbstractFlexible intermediate bulk containers are used in several industries, including the chemical, pharmaceutical, and food processing industries, for convenient handling of bulk solids and powders. While the electrostatic hazard posed by FIBCs is well known, little full‐scale experimental work has been performed to quantify this hazard.In this paper, experimental work conducted to evaluate the suitability of a new type of FIBC for use in common industrial flammable atmospheres is described. As a part of this work, two other FIBC types were evaluated for comparative purposes. Testing included determination of electrostatic discharge incendivity and measurement of charge transfer, surface potential, and charge density.The primary outcome of this work has been to establish the viability of a new type of FIBC for use in flammable atmospheres without the need for electrical grounding. However, consequent outcomes include a move towards a quantification of the electrostatic hazard posed by FIBC use and a better understanding of the mechanism characteristic of discharges from charged FIBC surfaces.
Carbon‐initiated effluent tank overpressure incident
Authors: Sherman R. E. , Crawford K. C. , Cusick T. M. , Csengery L. V. 
Published: June 2004

AbstractThis report provides, for information purposes, a description of an unusual event and the corrective actions undertaken by the Shell facility involved. Shell and the authors hope that this information will help personnel associated with other facilities understand a non‐obvious failure mechanism and take action to prevent their experienceing similar incidents.While drawn from actual experience, the information provided should be considered illustrative. Each company should review their own facilities, materials or processes to determine the appropriate equipment and procedures for their own specific circumstances.
Procedure for determining the distribution ranking index
Authors: Latino Michael A. 
Published: June 2004

AbstractThe Distribution Ranking Index (DRI) has been developed as a simple but effective means to indicate the inherent, acute hazards of a material that might be released in a transportation accident. Utilizing existing Dow resources and procedures, it is one of the methods used for prioritization of chemicals in Dow's distribution related process risk management effort.Seven individual hazard indexes are considered for a material. The values range from 1 to 4 with 4 representing the most severe hazard. The highest value from any hazard index determines the overall DRI.
Management of chemical plants using chemical compatibility information
Authors: Leggett David J. 
Published: June 2004

AbstractOSHA's Process Safety Management Standard, 29 CFR 1910.119 (September, 1992) requires that process hazard evaluations be performed on covered processes. The regulations contain 14 areas for consideration, six of which are related to the need to provide comprehensive information of all process materials, including the consequences of inadvertent mixing of process materials. This information can be made available to those involved in the manufacturing process through the development of an Interaction Matrix. A brief overview of the subject is given in a publication by the Center for Chemical Process Safety (CCPS) [1].In 1996 AIChE announced the availability of the computer package CHEMPAT that provides a straight‐forward method of generating and documenting the interaction matrix, or Compatibility Chart, and accompanying database. CHEMPAT was developed, and used internally, by the Dow Chemical Company since 1987. It was donated by Dow to AIChE in 1995 for use by the chemical process industries.This paper outlines the approach used to develop chemical compatibility information and briefly describes the use of CHEMPAT in that process.
Severe pressure surges in a simple pump‐pipeline‐valve system (and what to do about it)
Authors: Anderson A. , Simpson A. R. , McPheat J. G. 
Published: June 2004

AbstractA Simple case study of a relatively high‐friction pipeline with pump‐assisted gravity flow (e.g., for high viscosity fluids such as hydrocarbon products) illustrates three features which lead to unexpectedly high transient pressure surges for which conventional alleviation practices (such as extended value‐closure times or surge‐relief devices at the pump discharge) are ineffective:

the use of a value to control flow in a long or high‐friction pipeline;
a system with a value closure a significant distance downstream of a pump; and
a system where surge protection is located a significant distance away from a control value.
Improved safety through distributed manufacturing of hazardous chemicals
Authors: Koch T. A. , Krause K. R. , Mehdizadeh M. 
Published: June 2004

AbstractLarge scale centralized manufacture of chemicals coupled with distribution to remote customers has obvious economic advantages derived from economy of scale. In some cases, however, concern for safety and environment can drive a search for competitive small scale processes for production of toxic chemicals at the end‐use site, thereby eliminating the potential hazards associated with transportation. We will present a case study in which novel technology is being explored to develop a safe, economically attractive process with minimal waste for the synthesis of hydrogen cyanide.
The use of slam shut valves on LCA plants
Authors: McConnell R. A. 
Published: June 2004

AbstractOne of the many novel features on ICI's leading Concept Ammonia Plants is the use of Slam Shut Valves instead of safety relief valves for certain important relief duties. The design intention was to reduce the environmental impact of gas releases to the vent and flare systems, to allow a smaller vent and flare system to be installed, and to contain gas within the plant systems to allow rapid re‐start following a plant upset giving considerable savings in flaring and plant re‐start time. As the design proceeded throughout 1984–86, various implications of the design were revealed, and these are discussed in this paper. Nearly 15 years of operating and maintenance experience on the 2 plants at ICI's Severnside factory have justified the decision to use Slam Shut Valves.
Out‐of‐the‐loop performance problems and the use of intermediate levels of automation for improved control system functioning and safety
Authors: Kaber David B. , Endsley Mica R. 
Published: June 2004

AbstractHuman supervisory control and monitoring of automated systems, as well as, passive system(s) information processing can all be classified as forms of out‐of‐the‐loop (OOTL) performance. Whether the operator's task is to decide if process control intervention is necessary, detect a critical system event, or accept or reject the actions of a computer controller, he or she is removed from direct, real‐time control of the system. OOTL performance is a critical issue in overall automated systems functioning because it is associated with numerous negative consequences including: (a) operator failure to observe system parameter changes and intervene when necessary (vigilance decrements); (b) human over‐trust in computer controllers (complacency); (c) operator loss of system or situation awareness; and (d) operator direct/manual control skill decay. These consequences have been found to impact human performance under both normal operating conditions and system failure modes, with a greater effect on the latter [15] leading to serious problems in operator ability to perform their assigned tasks when working with automated systems.Level of automation (LOA) has been put forth as an approach to ameliorating OOTL performance problems. It is intended to determine the optimal assignment of control between a human operator and computer in order to keep both involved in system operations. LOA considers the capabilities and capacities of both the human and computer controller in determining their optimal coupling. It constitutes a systems approach to resolving OOTL performance problems by minimizing the negative consequences associated with the removal of the operator from active system control, and allows for the strengths of both human decision making and computer processing to be realized. When compared to a technological approach that assesses only the capabilities of the computer in allocating as much responsibility to the machine as possible, and assigning the remaining tasks to the human operator, the advantages can be considerable.A LOA taxonomy will be presented along with research examining its utility in a dynamic control task. Using LOA to identify optimal combinations of human and computer control was found to produce improvements in system performance under intermediate levels. These levels involve joint human and computer control of various system functions, such as monitoring, planning, and option selection and implementation. Results indicated decreases in the number of system processes/tasks overlooked by operators. These improvements may translate into cost reductions due to improved operational safety and are anticipated to be applicable to process control operations.
An overview of SuperChems for DIERS: A program for emergency relief system and effluent handling designs
Authors: Melhem G. A. , Fisher H. G. 
Published: June 2004

AbstractThe Design Institute for Emergency Relief Systems (DIERS) Users Group awarded Arthur D. Little, Inc., a contract to provide the next generation computer program for emergency relief system and effluent handling designs.The new computer program, SuperChems for DIERS, is a dynamic simulator, capable of performing emergency relief system and effluent handling designs for complex geometries and multiphase reaction systems. In addition, SuperChems for DIERS is an equation‐of‐state based program which provides several benefits over existing non‐equation‐of‐state based methods for systems involving supercritical reactions like polymerizationsof butadiene and acrylonitrile, solution effects such as HCl/Water, and a priori determination of phase splitting.This new computer program allows the user to dynamically simulate several common configurations for vent containment design. For example, the user is able to simulate a vessel discharging a two‐phase mixture into a quench/vent where the catch/vent tank will vent to a stack or a scrubber. Unit operations available include separators (horizontal and vertical), cyclones, etc. The impact of back pressure and continuing reaction in the vent containment system is accounted for in the dynamic simulations.
Decomposition of thermally unstable chemicals in solvents
Authors: Chervin Sima , Evon Skip E. , Bodman Glenn T. 
Published: June 2004

AbstractKnowledge of the decomposition reactions of chemicals when tested neat versus in mixtures with various solvents is essential for process safety studies. The decomposition of several mercaptotetrazole derivatives was studied by differential scanning calorimetry, both neat and in seven different solvents. Most mixtures exhibited destabilization of the chemical in the solvent compared with the neat material, resulting in a lower decomposition onset temperature in the mixture. It was demonstrated that the decomposition mechanism and kinetics changed significantly when these chemicals were mixed with solvents. The highly variable effects on thermal stability from mixing thermally unstable chemicals with solvents demonstrates the value of thermal stability testing of reaction mixtures as integral part of process hazard identification.
Toxic hazard reduction with passive mitigation systems
Authors: Myers Philip M. , Morgan Richard S. , Flamberg Stephanie A. 
Published: June 2004

AbstractA major component of the United States Environmental Protection Agency's 112(r) Risk Management Program Rule is the evaluation and control of potential public exposures to toxic chemicals. The rule requires identification and evaluation of a worst case accidental toxic release scenario, but provides for the inclusion of passive mitigation systems in modeling the dispersion hazard zones that are to be communicated to the public. These passive mitigation systems can be taken into account in the consequence modeling if they will withstand the initiating event that causes the accidental release and function as intended.This paper discusses several passive mitigation systems that can be designed as an integral part of storage or processing of highly toxic chemicals. These include, but are not limited to, optimizing storage conditions, design of secondary containment, toxic vapor generation control, and enclosure design. The effectiveness of various passive mitigation systems is evaluated using consequence modeling for case studies involving highly toxic chemicals such as phosgene, chlorine, and ethylene oxide.
The influence of the geometry of the hot surfaces on the autoignition of vapor/air mixture: Some experimental and theoretical results
Authors: Duarte Dayse , Rohatgi Janardan , Judice Raul 
Published: June 2004

AbstractTwo major accidents in the 80's: the summit Tunnel Fire, England and Piper Alpha disaster, an offshore platform in the North Sea; and very recently, possible explosion of the Boeing, TWA flight 800 at New York, makes it imperative that further research into the mechonisms of the ignition of flammable vapor/air mixture in contact with hot surfaces needs to be done. There have been a number of studies of ignition by hot surfaces, but in all these studies the ignition sources were wire, sphere or strip, i.e., most of them were flat surfaces. But to the authors' knowledge, other variables which affect the ignition mechanism such as irregular geometrical shapes have not been studied. The purpose of this paper is to examine how the degree of confinement (or, configuration), size and orientation, of the heated surface affects the ignition temperature of the flammable vapors. The results were obtained by experimentnal and by computational fluid dynamics.
Short communication: Estimating the minimum ignition energy of hybrid mixtures
Authors: Britton Laurence G. 
Published: June 2004

AbstractA simple analytical method is presented for estimating the hybrid minimum ignition energy (HMIE) of dust–gas mixtures, based on the assumed generality of Bartknecht's well‐known test data for mixtures of propane with a series of dusts in air. Since the HMIE equation requires input data which might be unavailable, the use of conservative default methods is discussed.