Abstract. 1. Introduction. 2. Risk Monitors

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1 IBP2955_10 CONTINUOUS MONITORING OF RISK AND RELIABILITY IN INTEGRATED AND DISTRIBUTED SYSTEMS Jesús Salomón Llanes 1, Manuel Perdomo Ojeda 2, Jesús Rivero Oliva 3, Dany Sánchez Domínguez 3, Diego Frías 3 Copyright 2010, Instituto Brasileiro de Petróleo, Gás e Biocombustíveis - IBP Este Trabalho Técnico foi preparado para apresentação na Rio Oil & Gas Expo and Conference 2010, realizada no período de 13 a 16 de setembro de 2010, no Rio de Janeiro. Este Trabalho Técnico foi selecionado para apresentação pelo Comitê Técnico do evento, seguindo as informações contidas na sinopse submetida pelo(s) autor(es). O conteúdo do Trabalho Técnico, como apresentado, não foi revisado pelo IBP. Os organizadores não irão traduzir ou corrigir os textos recebidos. O material conforme, apresentado, não necessariamente reflete as opiniões do Instituto Brasileiro de Petróleo, Gás e Biocombustíveis, seus Associados e Representantes. É de conhecimento e aprovação do(s) autor(es) que este Trabalho Técnico seja publicado nos Anais da Rio Oil & Gas Expo and Conference Abstract This paper describes a system designed to continuous real-time monitoring of the risk in distributed industrial facilities that incorporates geo-referenced information, allowing the construction of dynamic maps of risk. The system consists of a set of monitors which cooperate with each other, and can be applied to plants and systems with high requirements of safety and reliability, as the oil industry, integrating production, refining and distribution. The base system is a computer code developed to perform Probabilistic Risk Assessment of level 1 that takes into account the operational status of principal and support systems as well as the expected responses to breakdown and accident initiator events. From the states sent by the local monitors the system creates a map indicating vulnerable areas and providing critical information needed for decision making in accidental and dangerous situations. 1. Introduction Reliability and risk studies of complex systems in Cuba started in the late 1980s with the Pre-operational Risk Assessment of the Juraguá Nuclear Power Plant. The authors, taking into account the high complexity (mainframe application) and low scalability and flexibility of the commercial softwares available in that time, decided to develop a new tool for Probabilistic Risk Assessment based on PC. As a result in 1990 the software ANCON was created (SALOMON and RIVERO, 1991; RIVERO et al., 1993). In ANCON new computational methods for solving fault trees were embedded (RIVERO et al., 1996) as well as new indexes reliability and graphical interfaces were included (SALOMON, 1997). The Probabilistic Risk Assessment methodology was posteriorly applied in other industries [RIVERO, 1999; SALOMON et al., 2000, SALOMON, 2000; CASTELLANOS E SALOMON, 2001] and also supported new maintenance programs focused on reliability and safety [MOSQUERA et al., 1994; TORRES et al., 1997; TORRES et al., 2000]. The authors also focused the development of methodologies for the determination of the initiators of accidents (PEREIRA and SALOMON, 1999), for the evaluation of the impact of organizational features (CASTELLANOS E SALOMON, 1999) as well as for the consideration of inter-dependent events and faults and human errors within the probabilistic framework (PERDOMO and FERRO, 2000) The success achieved in those applications justified the development of a new family of tools for real-time monitoring of reliability and risk indexes in industrial facilities. 2. Risk Monitors Taking into consideration the dynamic nature of the risk it was created a 5-stages methodology for its quantitative and continuos prediction in distributed systems (network of industrial facilities) as illustrated in Figure 1. First stage: Probabilistic Safety Analysis - PSA of each facility using technological project of the plant and standard component reliability databases. Second stage: PSA of each facility with real data from the plant live PSA. Third stage: Development of Risk Monitors for each facility: first off-line version followed by the on-line version. 1 Ph.D., Nuclear Engineer - Instituto Superior de Tecnologia y Ciencias Aplicadas (InSTEC), Habana, Cuba 2 Master, Nuclear Engineer - InSTEC, Habana, Cuba 3 Ph.D., Nuclear Engineer - D&D MASTERS, Bahia, Brazil

2 Fourth stage: Development of an expert system called Speaking Risk Adviser (SRA) in each facility. Fifth stage: Construction of a Supervised Network of Cooperative Speaking Risk Advisers supported by Geographic Information System. Figure 1. Multi-Stage Risk Monitor Development Procedure. 3. Static Probabilistic Risk Assessment In the first step a customized Probabilistic Risk Assessment (PRA) application was developed using state-ofthe-art techniques, safety and reliability concepts and indicators, some of them developed by the authors, like the concepts of vulnerability, prioritization, distribution and contribution, as well as average and instantaneous unavailability and point-wise and multi-parametric sensitivity. This application was used for stages 1 and 2 and later embedded into the monitor application developed in stage 3. Figure 2 shows the data used in a PRA. In Figure 3 screenshots of four codes used for PRA are shown. 4. Dynamic Risk Assessment Dynamic risk assessment differs from a sequence os static risk evaluation due to the fact that both present and future states depends on past states. It was necessary to introduce new indicators like the aperiodic curves of instantaneous unavailability, a novel feature embedded in the risk monitors. The on-line monitor demanded the creation of tools, in order to ensure the dynamics of the recording of operations and state parameters as well as to implement the calculation of estimates of new probabilistic indicators. In particular the dynamic relative importance of each component in the reliability and risk level of the plant as well as the determination of coupling factors that allows a decrease in the entropy of the Plant Operating State, were introduced. Off-line monitor is able to perform dynamic risk assessment in an industrial facility but reading temporal series of parameters and other operating, surveillance and maintenance data saved in the monitor database. In-line monitors are able to read real-time values from monitored parameters and perform instantaneous and continuous risk evaluation. To evolve from off-line to on-line monitor an interface with the automatic control system (PLC/HMI/ ESCADA) of the facilities had to be built. 4.1 Dynamic Reliability Database It was created a failure rate database for specific dynamic reliability assessment, based on cycles of records and information storage in a Thermoelectric Power Plant (CASTELLANOS, 2008), in a dangerous goods transportation company (SALOMON, 2008b), and in a crude oil pipeline (DE DIEGO et al., 2008) and in a ship terminal of a refinery (GARCIAS and SALOMON, 2008), used as test cases. A really challenging issue was the determination of reliability of trucks and ships parts and spares in terms of time and mileage when monitoring transportation activities (SALOMON 2

3 and RIVERO, 2001; SALOMON, 2008b). Figure 2. Data used for a PRA Probabilistic Risk Assessment. Notice that in many case the PRA results can suggest modifications in procedures and engineering specifications (indicated with a double-sense arrows). Figure 3. Screenshots of softwares (ANCON, ASeC, MOSEG and MRCh) included in the risk monitor system for qualitative, semi-quantitative and quantitative risk and reliability assessment. 5. Speaking Risk Adviser The recent advances in natural voice processing allowed the inclusion of an speaking interface to the Risk Analysis Expert System developed in the project for each monitored facility. The oral informations provided by the risk monitors allowed the operators to focus their attention on other consoles of the plant without disregarding the control of risk and reliability indicators. The Speaking Adviser can be set into three operational modes: (1) Normal Mode in which the monitor provides regularly oral information above the state of the monitored plant or facility, (2) Warning Mode in which the monitor provides only oral warnings when monitored indexes (usually risk and/or reliability) 3

4 achieves prefixed alarm levels, and (3) Emergency Mode in which the monitor provides oral information only when an emergency occurs. Lower levels include information of higher levels. For example, when setting Operational Mode 1 it implies that the information of levels 1 (Normal), 2 (Warning) and 3 (Emergency) is provided to the operator. 6. Cooperative Distributed Speaking Risk Monitor Network supported by GIS This higher level application allows the integrated monitoring of distributed industrial systems producing risk and hazard maps supported by geographic information systems (GIS), as shown in Figure 4. This application, which is the server (master) of a network of risk monitors, uses a new kind of dynamic event tree that takes into account the geographical position (and/or the relative position within the distributed industrial system) where the initiator event occurs. Figure 4. Map of risk generated by the Risk Monitor implemented in an oil duct in Varadero- Matanzas, Cuba (2007). This application can be set to assess dynamically the potential risk at territorial level, before the occurrence of different events, both natural as human-induced, as well as to maintain a careful monitoring before, during and after the occurrence of initiator events. The risk monitor network uses dynamic probabilistic models previously developed for multiple scenarios, and is able to assign priorities based on risk criteria, according to information generated by the network of risk monitors. It is done via establishment of a hierarchical level of prioritization based decision-making function of the magnitude of the harms associated with initiator events (SALOMON 2008a). 7. Conclusions In this works the authors shared their experience in developing an Speaking Cooperative Risk Monitor System. Risk monitors are designed for continuous dynamic risk assessment and prediction of hazardous sequences of events in distributed industrial systems. Speaking Cooperative Risk Monitor Networks has great potential for employment in the oil industry covering a large number of industrial activities interrelated with each other. Among the main features of this kind of system we have the immediacy of results considering multiple scenarios, and the large number of new indicators developed for this specific context. A knowledge database feeds an expert system provided with a configurable speaking interface for a better support (advertisement) to plant operators. 4

5 The risk monitor performs qualitative, semi-quantitative and quantitative evaluations of reliability and risk in the components of the geographically distributed system and uses these scores for calculation of territorial reliability and risk levels. 9. References SALOMÓN, J., RIVERO, J. ANCON 4.0: A PC software for reliability index calculation and level 1 Probabilistic Risk Assessment, Simposio internacional sobre el empleo de la evaluación probabilista de la seguridad a la seguridad operacional, EPS-91, Viena, Austria, RIVERO, J., SALOMÓN, J., TORRES, A., PERDOMO, M. El programa ARCON 4.1 para APS de nivel I, II Congreso Regional de Seguridad Radiológica y Nuclear, Zacatecas, México, MOSQUERA, G., RIVERO, J., SALOMÓN, J. Y OTROS. Confiabilidad de sistemas para el mantenimiento Industrial, Edit. Universidad Central de Venezuela, Caracas, Venezuela, RIVERO, J. Algoritmos para la evaluación de árboles de fallos complejos, Tesis de Doctorado, InSTEC, La Habana, Cuba, SALOMÓN, J. Desarrollo de las Aplicaciones de los Análises Probabilisticos de Seguridad, Tesis de Doctorado, InSTEC, La Habana, Cuba, TORRES, A., RIVERO, J., SALOMÓN, J., MIARI, E. El enfoque probabilista, una solución factible a la gestión del mantenimiento actual, CIDIM-97, Instituto Superior Politécnico José Antonio Echevarria, Cuba, RIVERO, J., SALOMÓN, J. Experiences on the application of the PSA methodology in the industry, Technical Committee Metting on PSA Applications to innprove NPP Safety. Madrid, Spain, p , PEREIRA, G., SALOMÓN, J. Análisis de Causa Raíz de Incidentes empleado las técnicas de Cascada de Tormenta de Ideas Inducidas con Ciclos de Control, III Taller Cátedra de Seguridad de la Industria, Habana, Cuba, CASTELLANOS, V., SALOMÓN, J. Metodología para la evaluación de los factores organizativos, en la confiabilidad operacional de la CTE, III Taller de la Cátedra de Seguridad de la Industria, Habana, Cuba, PERDOMO, M., FERRO, A. Análisis de Falla Dependiente y Errores Humanos, Universidad Central de Venezuela. Editora Universidad Central de Venezuela, Caracas, Venezuela, SALOMÓN, J., PERDOMO, M., Y OTROS Análisis de Riesgo Industrial, Universidad Central de Venezuela. Editora Universidad Central de Venezuela, Caracas, Venezuela, TORRES, A., PIEDRA, M., SALOMÓN, J. Diseño de un Sistema de Control de Mantenimiento Orientado a la Disponibilidad y Seguridad de las Instalaciones DIAGNOS-2000, Instituto Superior Politécnico José Antonio Echevarria, Habana, Cuba, SALOMÓN, J. Evaluación Probabilista de Accidentes en Refinería, III Conferencia Internacional de Bomberos, Habana, Cuba, SALOMÓN, J., RIVERO, J. Control de fuentes móviles basado en monitores de Riesgo, SAFIN-2001, Universidad de la Habana, Cuba CASTELLANO, V., SALOMÓN, J. Entropía de los Estados Operativos en la Central Termoeléctrica de Mariel, SAFIN-2001, Universidad de la Habana, Cuba DE DIEGO, R., VERDE, J., SALOMÓN, J. Aplicación de Monitor de Riesgo en el Oleoducto Varadero Matanzas, II Taller de la Cátedra de Seguridad y Riesgo de Cuba, Habana, Cuba, GARCÍAS, M., SALOMÓN, J. Adaptación y aplicación de un Monitor de Riesgo Consejero Hablante en la Terminal 221 de la refinería Ñico López, II Taller de la Cátedra de Seguridad y Riesgo de Cuba, Habana, Cuba, CASTELLANOS, V. Monitor de Riesgo Consejero Hablante para Bloques Energéticos (Código MRch-CTE), Instituto Superior Politécnico José Antonio Echevarria, Habana, Cuba SALOMÓN, J. Concepción y Desarrollo de los Mapas de Riesgo Laboral y de Evaluación del Riesgo Dinámico soportada en Monitores de Riesgo Consejero Hablante, II Congreso Mundial de Riesgo, Guadalajara. 2008a SALOMÓN, J. Nueva concepción del Monitoreo de Buques para la Transportación de Cargas Peligrosas, VI Simposio Marítimo Internacional y Simposio Panamericano de Navegación en Águas Restringidas. Symmtechnaval. Habana, Cuba, 2008b. 5