No description available.

The advent of microprocessors has created the possibility of developing low cost adaptive controllers for small process plants which in the past badly needed but could not afford such controllers. To examine the practicality of developing advanced low cost microprocessor based controller, this thesis describes the development of a non-linear adaptive controller for a nylon crimping plant which is a typical example of small process plants. In order to test the algorithm on site, an algorithm development/implement device basing on a novel multi-tasking concept was developed. This novel microprocessor based device can perform program development, on-line algorithm test and data logging at the same time, while, still maintaining its small size for easy transportation. When the control algorithm was fully developed and tested, a low cost dedicated controller using an Intel 8085 processor was designed to house the algorithm and as a direct replacement of the original analogue controller.

No description available.

No description available.

Environmental Diagnosis of Process Plants by Life Cycle TechniquesHaydée A. Yrigoyen GonzálezEl objetivo de la investigación es desarrollar una herramienta que relacione aspectos desimulación, evaluación ambiental y análisis de sensibilidad. Para lo cual se estableció unametodología que consta de cinco niveles: Simulación de proceso, Inventario, evaluación deimpactos ambientales, análisis económico y análisis de sensibilidad.La metodología describe las variables relacionadas con el proceso, así como losimpactos asociados a cada una de sus etapas y la viabilidad económica del proceso, eidentifica las etapas de proceso con el mayor impacto ambiental (mediante el análisis desensibilidad).Para la simulación de procesos se empleó el simulador ASPEN Hysys®. El inventario,la evaluación de impactos y el análisis económico se lleva a cabo en hojas de cálculo de formaautomática.La obtención del inventario de efectos ambientales y la evaluación de loscorrespondientes impactos se realizan siguiendo la metodología de ciclo de vida, por lo que seconsideran las cargas ambientales asociadas a las materias primas, la generación deelectricidad y utilidades. Para obtener el inventario se construyó una base de datos quecontiene la información ambiental asociada a varios procesos industriales que se relacionanindirectamente al proceso bajo estudio. Similarmente, se incluyó una base de datos con losfactores de caracterización de las categorías de impacto más importantes.La validación de la metodología y de la herramienta desarrollada se ha llevado a cabomediante tres procesos industriales: polietileno de baja densidad (LDPE), óxido de etileno (EO)y biodiesel. Para cada proceso se han evaluado diferentes configuraciones para poderdeterminar cual de ellas es la mejor opción desde el punto de vista ambiental y económico.En el caso del LDPE, el cambio de configuración se ha enfocado en el origen de laelectricidad, la cual puede ser proveniente de la Red Nacional Española o de una unidad decogeneración. Los resultados indican que la mejor configuración corresponde al proceso queemplea electricidad proveniente de la unidad de cogeneración, puesto que se obtiene vaporcomo sub-producto y se evitan las emisiones asociadas a la generación de electricidad, lo quese refleja en una importante reducción de los impactos ambientales asociados.En el segundo proceso analizado, referente a la producción de oxido de etileno, se hanevaluado cuatro configuraciones, empleando aire u oxígeno como materia prima y electricidadde la Red Española o produciéndola mediante cogeneración. En relación al origen de laelectricidad, al emplear la cogeneración, el comportamiento ambiental del proceso mejoraconsiderablemente. En cuanto a la importancia de la materia prima empleada, al utilizaroxígeno se obtiene un mejor rendimiento en la etapa de reacción, con lo cual se compensa loscostes asociados a la materia prima con la productividad del proceso.Finalmente, se ha llevado a cabo la evaluación del proceso de producción de biodiesel,se comparó el comportamiento ambiental del proceso empleando un catalizador ácido y uncatalizador básico. En el proceso ácido se generan menores impactos ambientales. De formasimilar, ésta configuración tiene un mejor perfil económico ya que los costes asociados a laproducción son menores y no se requiere ninguna unidad de pretratamiento (necesaria en elproceso alcalino).Mediante la herramienta desarrollada, la información inicial puede modificarse encualquier momento con el fin de obtener los valores correspondientes a nuevas condiciones.Uno de los aspectos más importantes es el que la herramienta se adapta fácilmente con elmínimo de variaciones. Las bases de datos que se incluyen en las hojas de cálculo pueden seractualizadas por el usuario o ajustarse a las necesidades específicas de cada proceso. Todo elanálisis se lleva a cabo de forma automática, una vez introducida la información inicial delproceso e información económica.Environmental Diagnosis of Process Plants by Life Cycle TechniquesHaydée A. Yrigoyen GonzálezThe objective of this work is to develop a tool that integrates simulation, environmentalassessment and sensitivity analysis aspects. To support this tool, a methodology consisting offive levels was established. These are: process simulation, Inventory, environmental impactsassessment, economic analysis and sensitivity analysis.The developed methodology describes the variables related to the process, as well asthe impacts associated to each stages, the economic viability of the process, and the processstages with the highest environmental impact (by means of the sensitivity analysis).ASPEN Hysys® is the chosen software for the simulation of processes. The inventory,impact assessment and the economic analysis are automatically obtained in spreadsheets, bymeans of macros execution.The inventory and the impacts assessment are performed following the Life Cyclemethodology. Therefore, the environmental loads of the raw materials, electricity generation andutilities are considered. In order to generate the inventory, a data base was constructed; itcontains the environmental information associated to industrial processes that are indirectlyrelated to the process under study. Similarly, a data base with the characterization factors of themost important impact categories was included in the tool.The validation of the methodology and the developed tool has been accomplished bytheir application to three industrial processes: low density polyethylene (LDPE), ethylene oxide(EO) and biodiesel production. Different configurations have been evaluated for each process todetermine the best option from the environmental and economic point of view.For the LDPE process, the configuration change has focused in the origin of theelectricity, which can be supplied by the Spanish National Network or a cogeneration unit.Based on our results, the best configuration corresponds to the process employing electricity bycogeneration, since steam is obtained as by-product and the emissions associated to theelectricity generation are eliminated. These facts are reflected in an important reduction of theoverall impacts associated to this process.In the second analyzed process, referring to the production of ethylene oxide, fourconfigurations have been evaluated: using air or oxygen as raw material and electricity from theSpanish Network or produced by cogeneration. Related to the origin of the electricity, usingcogeneration, a better environmental profile is obtained. On the other hand, the oxygen as rawmaterial is better than air due to the best yield of ethylene oxide in the reaction stage. Due tothe better selectivity of the oxygen in the reaction, the costs of O2 as raw material arecompensated by high production.Finally, the process evaluation of the biodiesel production has been carried out. In thiscase, an acid and a basic catalyst were compared. The best configuration corresponds to theprocess using an acid catalyst. In the acid process lower environmental impacts are generated.Furthermore, this configuration has a better economical profile since the costs associated to theproduction are smaller and a pre-treatment unit is not required, as in the alkaline process.The initial information can be modified at any time to obtain the profile associated to thenew conditions by means of the developed tool. Also, the tool can be adapted to any process inan easy way. The included database can be updated or adjusted by the user at any time topersonalize them to the specific necessities of each process. Once the initial information isintroduced, the analysis is executed automatically.The developed tool is able to make the simulation, its environmental diagnosis,economic evaluation and the sensitivity analysis of any industrial process, introducing the initialoperation conditions.

The task of creating the operating procedures for a processing plant is time consuming and requires the involvement of key members of the design team. As one of the consequences, the writing of operating procedures is often put off till the final stages of the design process. However, some operability problems will remain hidden in the design until the operating procedure is considered. These problems are expensive to fix because they require undoing some of the design decisions that have already been made. This thesis reports on research into the automatic creation of operating procedures, a field of research sometimes called Operating Procedure Synthesis (OPS). One motivation for OPS research is to develop a tool that can detect operability problems in the design of a plant and thus allow operability problems to be considered earlier in the design process reducing the cost of resolving these problems. Previous OPS systems are generally based around single techniques such as mixed integer linear programming. All the techniques that have been examined in the past are strong in some aspects of OPS and weak in some other aspects. There is no single technique that is strong in all areas of OPS. As a result, no previous OPS system is able to generate all the procedures used as examples in the OPS literature. This thesis presents a new approach to OPS. In this approach, OPS is viewed as a set of distinct but related subtasks. Three subtasks have been identified and examined in this work, namely planning, safety and valve sequencing. Algorithms have been developed to address each of these three subtasks individually. These algorithms have been integrated to form a single OPS system by using a common representation of the operating procedure to be created.

Thesis (M. Eng.)(Chemical)--University of Pretoria, 2003. / Summaries in Afrikaans and English. Includes bibliographical references (leaves 83-86) and index. Available on the Internet via the World Wide Web.

Major accidents in the process industries occurred mostly as an outcome of multiple failures in different safety barriers and their interrelation with unsafe acts by frontline operators. This has become the reason why safety analyses in terms of plant technical aspects cannot be performed independently from analysing human response to the changing technology. Unsafe acts and errors by operators must be seen as a symptom of system insufficiencies and underlying problems, rather than as the cause of an accident. With this paradigm, the need to optimally configure the system and the whole working condition to understand human’s limitation and requirements becomes very evident. It is too naive to desire that human operators make zero error by asking them to change their behaviour and to perfectly adapt to the system. Human Factors (HF) attempts to cope with the need to understand the interrelation between human operators, the technology they are working with and the management system, with the aim to increase safety and efficiency. In achieving this goal, HF must be incorporated into the whole plant lifecycle, from the earliest design stage to plant operation and modifications. Moreover, HF analysis must comprise all kinds of operators’ activities and responsibilities in operating process plants, which can include manual works in field and supervisory control conducted remotely from a control centre/room. This work has developed techniques that provide systematic way to incorporate HF into process plant lifecycle. The new HF analysis technique, PITOPA-Design, in a combination with the classic PITOPA, is applicable for an implementation during design and operation of a plant. With the awareness that safety analysis and HF cannot be performed separately, an interconnection with HAZOPs is made possible by means of this new technique. Moreover, to provide a systematic analysis of operators’ work in control room, an additional technique, the PITOPA-CR was also developed. This HF technique can as well be integrated into a general HF analysis both during design phase and plant operation. In addition to it, results coming from PITOPA-CR will provide information required to optimally configure control and alarm system, as well as the whole alarm management system to better understand the limitation and requirements of control room operators. The structure of the development can be described as follows: i) Development of HAZOPA (the Hazards and Operator Actions Analysis), which provides the interconnection between HF analysis and HAZOPs, ii) Development of PITOPA-Design, a technique to incorporate HF consideration into design phase, which is differentiated into 3 stages to comprise the conceptual design, the basic engineering and the detail engineering phase, iii) Development of PITOPA-CR, a technique for HF analysis in control room, iv) Integration of PITOPA-CR into alarm management system, development of a technique for alarm prioritization. / Schwere Unfälle in der Prozessindustrie erfolgen meist aus einem Zusammenspiel mehrerer verschiedener Fehler und der gleichzeitigen Wechselwirkung mit falschem menschlichem Handeln. Dabei sind diese Fehlhandlungen nicht als Unfallursache anzusehen, sondern sie resultieren aus Fehlern, die in dem System selbst zu finden sind. Aus diesem Grund kann bei der Sicherheitsanalyse die technische Analyse nicht unabhängig von der Betrachtung des Human Factors (HF) durchgeführt werden. Um eine Reduzierung der Fehlhandlungen zu erreichen, müssen das Anlagendesign, die Bedienbarkeit und die Arbeitsumgebung an die menschlichen Fähigkeiten angepasst werden. Human Factors (HF) betrachtet die Interaktion zwischen menschlichen, technischen und organisatorischen Aspekten einer Anlage, mit dem Ziel die Sicherheit und Effektivität der Anlage zu optimieren. Dafür ist eine Einbindung von HF in den gesamten Lebenszyklus einer Anlage notwendig. So müssen HF- Analysen nicht nur während des Betriebs einer Anlage und bei Prozessmodifikationen durchgeführt werden, sondern auch während des gesamten Design- Prozesses, da gerade in den frühen Design-Phasen das Optimierungspotential besonders hoch ist. Eine solche Analysemethode muss alle Aufgaben eines Operators erfassen, so dass zwischen manueller Arbeit und der Arbeit in der Leitwarte unterschieden werden muss. In dieser Arbeit wurden Analysentechniken entwickelt, die einen systematischen Ansatz zur Berücksichtigung des HF über den gesamten Lebenszyklus einer verfahrenstechnischen Anlage darstellen. Mit Hilfe der neuen Analysemethode, PITOPA-Design, können Untersuchungen sowohl während der Designphase als auch während des Betriebs einer Anlage durchgeführt werden. Da solche HF-Analyse immer in Verbindung mit einer klassischen Sicherheitsanalyse erfolgen muss, bindet die neue Methode die HAZOP-Analyse direkt ein. Darüber hinaus wurde ein weiterer Ansatz für die Analyse von Operatorhandlungen in einer Messwartenarbeit entwickelt. Diese neue Analysentechnik, PITOPA-CR, bildet die Grundlage für Verbesserungen im Alarmsystem und wird in das Alarmmanagementsystem eingebunden. Die Arbeit ist wie folgt strukturiert: i) Entwicklung von HAZOPA (the Hazards and Operator Actions Analysis). Diese Methode stellt die Einbindung der HF-Analyse in HAZOP dar. ii) Entwicklung von PITOPA-Design, zur HF-Analyse während des gesamten Designprozesses einer verfahrenstechnischen Anlage. Die Methode wurde in 3 Teile eingeteilt, um die drei Designsphasen Conceptual-, Basic-, und Detail-Design zu erfassen. iii) Entwicklung von PITOPA-CR, zur HF-Analyse in der Messwarte. iv) Einbindung von PITOPA-CR in das Alarmmanagementsystem und Entwicklung einer Technik zur Alarmpriorisierung.

Major accidents in the process industries occurred mostly as an outcome of multiple failures in different safety barriers and their interrelation with unsafe acts by frontline operators. This has become the reason why safety analyses in terms of plant technical aspects cannot be performed independently from analysing human response to the changing technology. Unsafe acts and errors by operators must be seen as a symptom of system insufficiencies and underlying problems, rather than as the cause of an accident. With this paradigm, the need to optimally configure the system and the whole working condition to understand human’s limitation and requirements becomes very evident. It is too naive to desire that human operators make zero error by asking them to change their behaviour and to perfectly adapt to the system. Human Factors (HF) attempts to cope with the need to understand the interrelation between human operators, the technology they are working with and the management system, with the aim to increase safety and efficiency. In achieving this goal, HF must be incorporated into the whole plant lifecycle, from the earliest design stage to plant operation and modifications. Moreover, HF analysis must comprise all kinds of operators’ activities and responsibilities in operating process plants, which can include manual works in field and supervisory control conducted remotely from a control centre/room. This work has developed techniques that provide systematic way to incorporate HF into process plant lifecycle. The new HF analysis technique, PITOPA-Design, in a combination with the classic PITOPA, is applicable for an implementation during design and operation of a plant. With the awareness that safety analysis and HF cannot be performed separately, an interconnection with HAZOPs is made possible by means of this new technique. Moreover, to provide a systematic analysis of operators’ work in control room, an additional technique, the PITOPA-CR was also developed. This HF technique can as well be integrated into a general HF analysis both during design phase and plant operation. In addition to it, results coming from PITOPA-CR will provide information required to optimally configure control and alarm system, as well as the whole alarm management system to better understand the limitation and requirements of control room operators. The structure of the development can be described as follows: i) Development of HAZOPA (the Hazards and Operator Actions Analysis), which provides the interconnection between HF analysis and HAZOPs, ii) Development of PITOPA-Design, a technique to incorporate HF consideration into design phase, which is differentiated into 3 stages to comprise the conceptual design, the basic engineering and the detail engineering phase, iii) Development of PITOPA-CR, a technique for HF analysis in control room, iv) Integration of PITOPA-CR into alarm management system, development of a technique for alarm prioritization.:ACKNOWLEDGEMENT i ABSTRACT iii ZUSAMMENFASSUNG iv CONTENTS v TABLE OF FIGURES viii LIST OF TABLES x NOMENCLATURE xi ACRONYMS AND ABBREVIATIONS xii CHAPTER 1 1 INTRODUCTION 1 1.1 Background 1 1.2 Objectives 2 1.3 Scope of Work 3 CHAPTER 2 5 THEORETICAL BACKGROUND 5 2.1 Fundamentals of Human Error 5 2.2 Human Factors (HF) 8 2.3 Motivations to Consider HF in Process Safety 9 2. 3. 1 Accidents that Address HF in Process Safety 11 2. 3. 2 Regulation and Legal Requirements 16 2. 3. 3 Business Value 19 2.4 Work of Operators in Complex Systems 19 2. 4. 1 Role of Operators in Complex Systems 20 2. 4. 2 Problems with Computerisation and Automation 24 2. 4. 3 Allocation of Functions and Levels of Automation 25 2.5 Performance Influencing Factors (PIFs) 27 2.6 Distributed Control System (DCS) and Alarm Systems 29 2. 6. 1 Alarm, Alarm System and Alarm Management 30 2. 6. 2 Most Common Alarm Problems 33 2. 6. 3 Improving Alarm Performance through Prioritization 34 2.7 Safety Analysis Methods 38 2.7.1 Qualitative Safety Analysis 39 2.7.2 Quantitative Safety Analysis 43 2.8 Mathematical Algorithms 44 2.8.1 Techniques for Multi-Criteria Decision Making (MCDM) 44 2.8.2 Classification Methods 47 CHAPTER 3 50 RECENT DEVELOPMENTS IN HF STUDIES 50 3. 1 Methods for HF analysis 50 A. Task Analysis 50 B. Techniques for Operators Actions Analysis 51 3. 2 Human Reliability Analyses (HRA) 52 3. 3 Consideration of Human Error in HAZOP 53 3. 4 HF in Process Plant Design 54 3. 5 HF in Alarm Management and DCS-Design 55 3. 6 The Need for Further Development of HF Methods 57 CHAPTER 4 58 MOTIVATION OF THE WORK 58 CHAPTER 5 61 PROCESS INDUSTRY TOOL FOR OPERATOR ACTIONS ANALYSIS (PITOPA) 61 5.1 The New Technique for Operator Actions Analysis (OAA) 64 5.2 Technique for Performance Influencing Factors (PIFs) Evaluation 65 5.3 Validation of PITOPA in the Process Industry 67 CHAPTER 6 71 EXTENDING HAZOP TO INTEGRATE HF INTO 71 GENERAL SAFETY ANALYSIS 71 6.1 Development of HAZOPA (The Hazard, Operability and Operator Actions Analysis) 72 6.2 Case Study 75 CHAPTER 7 85 APPROACH TO INCORPORATING HF CONSIDERATION 85 INTO PLANT DESIGN 85 7.1 Development of an Approach for HF Analysis in Design – The PITOPA-Design 85 7.1.1 HF Analysis in Conceptual Design Phase (HFAD–Conceptual) 88 7.1.2 HF Analysis in Basic Engineering (HFAD – Basic) 93 7.1.3 HF Analysis in Detail Engineering (HFAD-Detail) 107 7.2 Technique for HF-Design Parameters Evaluation 109 7.3 Intermediate Summary 114 CHAPTER 8 115 IMPLEMENTATION OF THE NEW PITOPA-DESIGN: 115 A CASE-STUDY 115 8.1 Conceptual Design 115 8.2 Basic Engineering 123 8.3 Detail Engineering 127 CHAPTER 9 132 APPROACH FOR IMPROVING OPERATOR PERFORMANCE 132 IN CONTROL ROOM 132 9.1 Performance Influencing Factors (PIFs) for Supervisory & Monitoring Tasks 134 9.2 Development of PITOPA-Control Room (PITOPA-CR) 140 9.2.1 Analysis of Normal Operation 142 9.2.2 Analysis of Abnormal Operation 150 9.3 Alarm Prioritization 156 9.3.1 A survey on Alarm Prioritization 156 9.3.2 Incorporation of CROAA into Alarm Prioritization 157 9.4 Intermediate Summary 165 CHAPTER 10 167 INCORPORATION OF OPERATOR ACTIONS ANALYSIS INTO ALARM MANAGEMENT 167 CHAPTER 11 171 RESULTS AND FUTURE WORKS 171 11. 1 Results 171 11. 2 Future Works 172 BIBLIOGRAPHY 174 APPENDIX A A-1 APPENDIX B B-1 / Schwere Unfälle in der Prozessindustrie erfolgen meist aus einem Zusammenspiel mehrerer verschiedener Fehler und der gleichzeitigen Wechselwirkung mit falschem menschlichem Handeln. Dabei sind diese Fehlhandlungen nicht als Unfallursache anzusehen, sondern sie resultieren aus Fehlern, die in dem System selbst zu finden sind. Aus diesem Grund kann bei der Sicherheitsanalyse die technische Analyse nicht unabhängig von der Betrachtung des Human Factors (HF) durchgeführt werden. Um eine Reduzierung der Fehlhandlungen zu erreichen, müssen das Anlagendesign, die Bedienbarkeit und die Arbeitsumgebung an die menschlichen Fähigkeiten angepasst werden. Human Factors (HF) betrachtet die Interaktion zwischen menschlichen, technischen und organisatorischen Aspekten einer Anlage, mit dem Ziel die Sicherheit und Effektivität der Anlage zu optimieren. Dafür ist eine Einbindung von HF in den gesamten Lebenszyklus einer Anlage notwendig. So müssen HF- Analysen nicht nur während des Betriebs einer Anlage und bei Prozessmodifikationen durchgeführt werden, sondern auch während des gesamten Design- Prozesses, da gerade in den frühen Design-Phasen das Optimierungspotential besonders hoch ist. Eine solche Analysemethode muss alle Aufgaben eines Operators erfassen, so dass zwischen manueller Arbeit und der Arbeit in der Leitwarte unterschieden werden muss. In dieser Arbeit wurden Analysentechniken entwickelt, die einen systematischen Ansatz zur Berücksichtigung des HF über den gesamten Lebenszyklus einer verfahrenstechnischen Anlage darstellen. Mit Hilfe der neuen Analysemethode, PITOPA-Design, können Untersuchungen sowohl während der Designphase als auch während des Betriebs einer Anlage durchgeführt werden. Da solche HF-Analyse immer in Verbindung mit einer klassischen Sicherheitsanalyse erfolgen muss, bindet die neue Methode die HAZOP-Analyse direkt ein. Darüber hinaus wurde ein weiterer Ansatz für die Analyse von Operatorhandlungen in einer Messwartenarbeit entwickelt. Diese neue Analysentechnik, PITOPA-CR, bildet die Grundlage für Verbesserungen im Alarmsystem und wird in das Alarmmanagementsystem eingebunden. Die Arbeit ist wie folgt strukturiert: i) Entwicklung von HAZOPA (the Hazards and Operator Actions Analysis). Diese Methode stellt die Einbindung der HF-Analyse in HAZOP dar. ii) Entwicklung von PITOPA-Design, zur HF-Analyse während des gesamten Designprozesses einer verfahrenstechnischen Anlage. Die Methode wurde in 3 Teile eingeteilt, um die drei Designsphasen Conceptual-, Basic-, und Detail-Design zu erfassen. iii) Entwicklung von PITOPA-CR, zur HF-Analyse in der Messwarte. iv) Einbindung von PITOPA-CR in das Alarmmanagementsystem und Entwicklung einer Technik zur Alarmpriorisierung.:ACKNOWLEDGEMENT i ABSTRACT iii ZUSAMMENFASSUNG iv CONTENTS v TABLE OF FIGURES viii LIST OF TABLES x NOMENCLATURE xi ACRONYMS AND ABBREVIATIONS xii CHAPTER 1 1 INTRODUCTION 1 1.1 Background 1 1.2 Objectives 2 1.3 Scope of Work 3 CHAPTER 2 5 THEORETICAL BACKGROUND 5 2.1 Fundamentals of Human Error 5 2.2 Human Factors (HF) 8 2.3 Motivations to Consider HF in Process Safety 9 2. 3. 1 Accidents that Address HF in Process Safety 11 2. 3. 2 Regulation and Legal Requirements 16 2. 3. 3 Business Value 19 2.4 Work of Operators in Complex Systems 19 2. 4. 1 Role of Operators in Complex Systems 20 2. 4. 2 Problems with Computerisation and Automation 24 2. 4. 3 Allocation of Functions and Levels of Automation 25 2.5 Performance Influencing Factors (PIFs) 27 2.6 Distributed Control System (DCS) and Alarm Systems 29 2. 6. 1 Alarm, Alarm System and Alarm Management 30 2. 6. 2 Most Common Alarm Problems 33 2. 6. 3 Improving Alarm Performance through Prioritization 34 2.7 Safety Analysis Methods 38 2.7.1 Qualitative Safety Analysis 39 2.7.2 Quantitative Safety Analysis 43 2.8 Mathematical Algorithms 44 2.8.1 Techniques for Multi-Criteria Decision Making (MCDM) 44 2.8.2 Classification Methods 47 CHAPTER 3 50 RECENT DEVELOPMENTS IN HF STUDIES 50 3. 1 Methods for HF analysis 50 A. Task Analysis 50 B. Techniques for Operators Actions Analysis 51 3. 2 Human Reliability Analyses (HRA) 52 3. 3 Consideration of Human Error in HAZOP 53 3. 4 HF in Process Plant Design 54 3. 5 HF in Alarm Management and DCS-Design 55 3. 6 The Need for Further Development of HF Methods 57 CHAPTER 4 58 MOTIVATION OF THE WORK 58 CHAPTER 5 61 PROCESS INDUSTRY TOOL FOR OPERATOR ACTIONS ANALYSIS (PITOPA) 61 5.1 The New Technique for Operator Actions Analysis (OAA) 64 5.2 Technique for Performance Influencing Factors (PIFs) Evaluation 65 5.3 Validation of PITOPA in the Process Industry 67 CHAPTER 6 71 EXTENDING HAZOP TO INTEGRATE HF INTO 71 GENERAL SAFETY ANALYSIS 71 6.1 Development of HAZOPA (The Hazard, Operability and Operator Actions Analysis) 72 6.2 Case Study 75 CHAPTER 7 85 APPROACH TO INCORPORATING HF CONSIDERATION 85 INTO PLANT DESIGN 85 7.1 Development of an Approach for HF Analysis in Design – The PITOPA-Design 85 7.1.1 HF Analysis in Conceptual Design Phase (HFAD–Conceptual) 88 7.1.2 HF Analysis in Basic Engineering (HFAD – Basic) 93 7.1.3 HF Analysis in Detail Engineering (HFAD-Detail) 107 7.2 Technique for HF-Design Parameters Evaluation 109 7.3 Intermediate Summary 114 CHAPTER 8 115 IMPLEMENTATION OF THE NEW PITOPA-DESIGN: 115 A CASE-STUDY 115 8.1 Conceptual Design 115 8.2 Basic Engineering 123 8.3 Detail Engineering 127 CHAPTER 9 132 APPROACH FOR IMPROVING OPERATOR PERFORMANCE 132 IN CONTROL ROOM 132 9.1 Performance Influencing Factors (PIFs) for Supervisory & Monitoring Tasks 134 9.2 Development of PITOPA-Control Room (PITOPA-CR) 140 9.2.1 Analysis of Normal Operation 142 9.2.2 Analysis of Abnormal Operation 150 9.3 Alarm Prioritization 156 9.3.1 A survey on Alarm Prioritization 156 9.3.2 Incorporation of CROAA into Alarm Prioritization 157 9.4 Intermediate Summary 165 CHAPTER 10 167 INCORPORATION OF OPERATOR ACTIONS ANALYSIS INTO ALARM MANAGEMENT 167 CHAPTER 11 171 RESULTS AND FUTURE WORKS 171 11. 1 Results 171 11. 2 Future Works 172 BIBLIOGRAPHY 174 APPENDIX A A-1 APPENDIX B B-1

Background: The Digital Twin is an increasingly trending technology that utilizes many of the key technologies relevant to the digitalization of industries and Industry 4.0, such as AI, Big Data, and IoT, to bring a virtual asset and a physical asset together to perform analysis and execute real-time decision making backed up by data (Grieves & Vickers, 2017; Rasheed et al., 2020). Current research on the benefits and challenges of Digital Twins in process industries is sparse and under-developed, and the significance of Digital Twins in their operational lifecycle phase requires investigation (Perno et al., 2020; Schleich et al., 2019; Sjödin, 2013). Research Questions: RQ1: What are the benefits of industrial process plant Digital Twins for companies in process industries? RQ2: What are the challenges that companies will face with industrial process plant Digital Twins in process industries? Literature Review: A theoretical framework was developed based on the applications, challenges, and enablers researched in other industries which acted as a foundation for the data collection process. Research Method: The thesis follows a qualitative research approach. A single-case study was employed with a large equipment supplier in the mineral processing industry, where data was collected through 17 semi-structured interviews with people possessing in-depth knowledge about the needs of the mineral processing industry. Findings: Five main benefits of industrial process plant Digital Twins in process industries were identified, Process performance, Monitoring and control, Predictive maintenance and scheduling, Business opportunities, and Safety. Correspondingly, four main challenges were identified, Perception and presentation, Privacy and security, Data management and performance, and Mutual scope and focus. Conclusions: The thesis project's managerial and theoretical implications include providing equipment suppliers in process industries with what benefits there lie with industrial process plant Digital Twins and which challenges must be overcome. By providing these benefits and challenges to equipment suppliers, they can prioritize which of these are most important to consider in their situation. The thesis contributes to the research of Digital Twins and adds to the sparse existing knowledge of what the benefits and challenges are of industrial process plant Digital Twins in process industries. The main limitation is the absence of process plant companies during the data collection phase.