Efficient water deluge nozzles arrangement on offshore installations for the suppression of pool fires
Introduction
Onshore and offshore platforms have the potential for various hazardous risks. In particular, fires with high temperatures may result in catastrophic consequences such as significant human casualties, economic losses and serious environmental pollution. The fire risk assessment and management, which includes presented rules and recommended practices, have been identified for reducing the risk of fire accidents (Czujko and Paik, 2012a, 2012b; Spouge, 1999; NORSOK, 2010; ABS, 2014; LR, 2014). In addition, design guidelines have been established to detail the methods of fire risk assessment and management (Nolan, 1996; Walker et al., 2003; Vinnem, 2007; Paik and Czujko, 2009, 2010; 2011, 2012; Paik et al., 2011).
Risk control options are effective means of minimising the probability of an event and its associated risk (UKOOA/HSE, 2006). Generally, active protection devices such as gas detectors and water spray systems are used as preventive and/or mitigating safety systems against fire accidents. Most installations have a two-tier alert system for preventing spurious shutdowns and unnecessary alerts. System failures generally occur when a detector fails to detect the specified information such as flammable gas, flame, smoke, heat, toxic gas and oil mist, or when the alarm or signal transmission systems fail to alert operators or activate emergency mitigation systems (DeFriend et al., 2008).
Water deluge systems are designed to cool equipment and control the growth of a fire by providing a simultaneous application of water over the entire fire hazard (ISO, 1999). For the efficient application of such water deluge systems, the location of the water deluge nozzles is important for ensuring their performance. The locations of the water deluge nozzles are usually selected through engineering judgments based on the deterministic approach (Dembele et al., 2007). However, the conventional method has an element of uncertainty in light of human error and accidental fires. To reduce the risk of such uncertainty, a probabilistic approach, based on credible fire scenarios, becomes necessary to select the locations of water deluge nozzles.
Numerous studies of fire-fighting systems have been performed (Svensson, 2002; Himoto and Tanaka, 2012; Jee et al., 2013; Alarifi et al., 2014). McCaffrey (1984) investigated the effect of water deluge on jet fires, and Prasad et al. (1999) conducted an experimental test for the suppression of pool fires with water deluge systems. Gosse and Hankinson (2001) and Hankinson and Lowesmith (2004) carried out large-scale studies to investigate the mitigation effect of water deluge systems on jet and pool fires.
Regarding active protection systems, some research has contributed to the application of the probabilistic approach. Seo et al. (2013) introduced a method for determining efficient gas detector locations using a quantitative approach. Recently, Kim et al. (2016) stressed water deluge location in the control of jet fires, and successfully implemented the approximate optimisation method to calculate the efficient nozzle locations for offshore platforms. They suggested the use of a water deluge index, based on the characteristics of jet fires, to determine the efficient locations of water deluge nozzles. The present paper is a sequel to the previous paper (Kim et al., 2016). In contrast to the previous paper, which concerned jet fires, this paper focuses on pool fires. Pool fires have different characteristics than jet fires, and thus a proper method should be developed to reflect those characteristics. The aims of this study are to use the water deluge location index for pool fires (WLIP) to suggest an efficient method of arrangement based on a probabilistic approach, and to verify the effectiveness of the proposed methodology for the arrangement of water deluge nozzles. Finally, this study compares its results with current industrial practices.
Section snippets
Jet fires
The location of water deluge nozzles has traditionally been determined based on engineering judgment and deterministic procedures. To reduce the risk of uncertainty in the conventional method, it is necessary to take a probabilistic approach based on engineering technology. Kim et al. (2016) successfully implemented a procedure for selecting efficient water deluge system locations to prevent, and reduce the consequences of, jet fire accidents on offshore installations. The WLI (water deluge
Target structure
Part of a hypothetical FLNG topside structure, is used as the target structure in the applied example. It consists of one deck, called the process deck (Fig. 3).
Selection of fire scenarios
The selection of a credible pool fire scenario is important for the determination of water spray positions. The Latin hypercube samplings (LHSs) technique (Ye, 1998) is used in this applied example for selecting the fire scenarios. The LHSs technique partitions each input distribution into N intervals of equal probability and selects
Concluding remarks
The aim of this study is to suggest a new method for the selection of water deluge nozzles to efficiently prevent and reduce the risk of pool fire accidents. The water deluge index for pool fires (WLIP) is calculated using the pool area and the frequency of fire scenarios. As the pool area is calculated with a simple equation, oil spill CFD analysis can be used to yield more precise results. The reliability of the WLIP is validated using risk-based comparison, which shows that the WLIP is more
Acknowledgements
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (NRF-2017R1A2B4004891).
References (40)
- et al.
Effects of fire-fighting on a fully developed compartment fire: temperatures and emissions
Fire Saf. J.
(2014) - et al.
A risk-based approach to flammable gas detector spacing
J. Hazard Mater.
(2008) - et al.
An experimental study of the effects of water mist characteristics on pool fire suppression
Exp. Therm. Fluid Sci.
(2013) - et al.
Effectiveness of area and dedicated water deluge in protecting objects impacted by crude oil/gas jet fires on offshore installations
J. Loss Prev. Process. Ind.
(2004) - et al.
A model for the fire-fighting activity of local residents in urban fires
Fire Saf. J.
(2012) - et al.
Performance-based fire fighting strategies for confined fire zones in nuclear power plants
Prog. Nucl. Energy
(2013) - et al.
Methods for determining the optimal arrangement of water deluge systems on offshore installations
Ocean Eng.
(2016) - et al.
Quantitative assessment of hydrocarbon explosion and fire risks in offshore installations
Mar. Struct.
(2011) - et al.
Simulation of water mist suppression of small scale methanol liquid pool fires
Fire Saf. J.
(1999) A study of tactical patterns during fire fighting operations
Fire Saf. J.
(2002)
Guidance Noted in Fire-fighting Systems
A test of goodness-of-fit
J. Am. Stat. Assoc.
Recommended Practice for Analysis, Design, Installation, and Testing of Safety Systems for Offshore Production Facilities. API RP 14C
A comprehensive program for calculation of flame radiation levels
Hydrocarbon explosion and fire engineering: assessing and managing hydrocarbon explosion and fire risks in offshore installations
Mar. Technol.
Paradigm change in safety design against hydrocarbon explosions and fires
FABIG Newsl.
Effectiveness of water deluge in fire suppression and mitigation
Fire Protection. DNV-os-d301
Use of water deluge to minimise hazards of oil and gas fires offshore
Offshore Hydrocarbon Release Statistics 2000, Offshore Technology Report N. OTO 2000-112
Cited by (5)
Phenomenological characteristics and flame radiation of dynamically evolving oil spill fires in a sealed ship engine room
2023, Ocean EngineeringCitation Excerpt :Here, a pool is characterized by a confined body of fuel, and it can form due to the liquid fuel released in a low spot, or can exist as a result of normal storage of fuels in tanks or containers (Liu et al., 2020). Moreover, a pool fire usually has a stable burning area with a rather thick oil layer (Ji et al., 2017; Lee et al., 2018; Wang et al., 2018). In contrast, the spill fires have two notable characteristics: (1) the combustion area changes dynamically, and there is a substantial uncertainty for different fire scenarios and boundary conditions; (2) the fuel thickness is generally on the order of millimeters, resulting in a less effective thermal feedback on the fuel surface (Hurley et al., 2016a).
Analysis of effectiveness of fire safety in machinery spaces
2019, Fire Safety JournalCitation Excerpt :While this wider safety research does not directly relate to fire safety in machinery spaces, its application may provide holistic improvements in fire safety in ships, which would ultimately include the machinery spaces. This systematic approach to accident prevention is not at the expense of analysis of individual features of fire prevention however and can be noted in the literature covering human and organisational factors, historical causal factors of fires in maritime transportation, calculation of fire probability [25–27], along with fire impact analysis research focusing on mitigating the outbreak of fire [28–41]. With the above in mind, the question is whether the prior assumptions that guide accident analysis, safety rules and regulations, etc. are indeed flawed.
Influence of Firefighting Intervention on Fire Spread Characteristics in Ship Engine Room
2023, Journal of Marine Science and EngineeringSimulation Research on Suppression and Extinguishment of Fires in a Ship Engine Room by Water Mist Based on FDS
2020, Ship Building of China