Hydrocarbon Fire Research Articles

Modelling the influence of hydrocarbon fire on offshore topside

Modelling the influence of hydrocarbon fire on offshore topside

Non-target screening reveals 124 PFAS at an AFFF-impacted field site in Germany specified by novel systematic terminology.

The uncontrolled release of aqueous film-forming foam (AFFF) ingredients during a major fire incident in Reilingen, Germany, in 2008 led to significant soil and groundwater contamination. As the identity of fluorochemical surfactants in AFFF are often veiled due to company secrets, it is important to characterize AFFF contaminations and their impact on the environment comprehensively. In this study, we adapted a systematic approach combining a suitable extraction method with liquid chromatography high-resolution quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) for an extensive non-targeted analysis. Our analysis identified 124 per- and polyfluoroalkyl substances (PFAS) from 42 subclasses in the contaminated soil (confidence levels of identification between 1 and 3). Typical for AFFF-impacted field sites, these included anionic, cationic, and zwitterionic substances with perfluoroalkyl chains spanning from 3 to 14 carbon atoms. Furthermore, we identified 1 previously unreported substance, and detected 9 PFAS subclasses for the first time in soil. AFFFs have long been employed to extinguish large hydrocarbon fires, yet their environmental consequences remain a concern. This study sheds light on the complex composition of AFFFs at this particularly contaminated area, emphasizing the necessity for extensive contaminant characterization as sound basis for informed management strategies to mitigate their adverse effects. AFFF PFAS are often named differently in the literature, leading to inconsistency in terminology. To address this issue, we introduced partially new terminology for AFFF-related PFAS to establish consistent terminology, to facilitate communication of identified compounds, and to ensure that the chemical structure can be directly derived from acronyms.

Shear performance of horizontally curved steel box bridge girders under hydrocarbon fire exposure conditions: Numerical investigation and design implications

Recent fire incidents indicated that fire-induced bridge collapse is commonly associated with local shear failures occurred in web plates. However, current studies provided failure modes only related to deflection arose from steel bridge girders, irrespective of the underlying shear mechanism. To bridge the knowledge gap, this study presents an investigation on structural behavior of horizontally curved steel box bridge girders (HCSBBGs) under the combined effects of hydrocarbon fire exposure and shear-dominant loadings. The numerical models are developed utilizing the ANSYS program, incorporating a validated thermal-structural analysis model and a shear limit analysis model that accounts for web initial imperfections. These models are further employed to examine effects of fire-shear load scenarios, curvature radius, web slenderness ratio, and aspect ratio on shear performance of HCSBBGs. Herein, deflections, degradation of shear capacity, and web out-of-plane displacement (WOPD) of the steel box bridge girders are discussed in detail. Failure modes of steel box bridge girders can be determined via moment-shear interaction diagrams as specified by Eurocode 3 (EC3). The findings indicate that decreasing web slenderness ratio and web aspect ratio can enhance shear capacity of steel box girders. Further, shear failure modes are predominant when fire occurs near side support of HCSBBGs. Current fire-resistant design practices relying on deflection or flexural limit based failure criteria, cannot be applicable in predicting fire resistance of steel box bridge girders under shear failure mode. Therefore, a failure criterion based on the ultimate web out-of-plane displacement ratio (UWOPDR), related to the web shear limit state, can be more suitable for predicting fire resistance of HCSBBGs.

Empirical prediction on boilover onset and impact for liquid hydrocarbon fire in atmospheric storage tank

Empirical prediction on boilover onset and impact for liquid hydrocarbon fire in atmospheric storage tank

Oil and Gas Structures: Forecasting the Fire Resistance of Steel Structures with Fire Protection under Hydrocarbon Fire Conditions

The hydrocarbon temperature–time curve is widely used instead of the standard curve to describe the temperature in the environment of structural surfaces exposed to fire in oil and gas chemical facilities and tunnels. This paper presents calculations of the ratio of time to reach critical temperatures at different nominal fire curves for steel structures such as bulkheads and columns with different types of fireproofing. The thermophysical properties of the fireproofing materials were obtained by solving the inverse heat conduction problem using computer simulation. It was found that the time interval for reaching critical temperatures in structures with different types of fireproofing in a hydrocarbon fire decreased, on average, by a factor of 1.2–1.7 compared to the results of standard fire tests. For example, for decks and bulkheads with mineral wool fireproofing, the K-factor of the ratio of the time for reaching the critical temperature of steel under the standard curve to the hydrocarbon curve was 1.30–1.62; for plaster, it was 1.56; for cement boards, it was 1.34; for non-combustible coatings, it was 1.38–2.0; and, for epoxy paints, it was 1.71. The recommended values of the K-factor for fire resistance up to 180 min (incl.) were 1.7 and, after 180 min, 1.2. The obtained dependencies would allow fireproofing manufacturers to predict the insulation thickness for expensive hydrocarbon fire experiments if the results of fire tests under standard (cellulosic) conditions are known.

Spontaneous ignition of corrugated cardboard under dynamic high radiant flux

Understanding the response of solid combustibles under high radiant fluxes is critical in predicting the thermal damage from extreme scenarios. Unlike the more moderate radiant fluxes in conventional hydrocarbon fires, extreme events such as strong explosion, concentrated sunlight and directed energy can generate dynamic radiant fluxes at the MW/m2 level, creating a unique threat to materials. This study investigates the pyrolysis and spontaneous ignition behaviors of corrugated cardboard by using both experimental and numerical methods, under 10-cm dynamic high radiant fluxes ranging from 0.2 to 1.25 MW/m2 for 10 s. The spontaneous ignition process at dynamic high radiant fluxes was recorded and quantified. Two ignition modes were found at the critical radiant flux of 0.4 MW/m2, namely hot-gas spontaneous ignition and hot-residue piloted ignition. The latter is not the focus of this paper due to its extremely small probability of occurrence. The research reveals that the increase in flux intensity induces shorter delay times for both pyrolysis and ignition, lower ignition energy density, along with a corresponding rise in the critical mass flux and surface temperature at ignition moment. The simulation results are generally aligned with the experimental findings, despite some divergences may be attributed to model simplifications and parameter assumptions. The work contributes to a deeper insight into material behavior under extreme radiation, with valuable implications for fire safety and hazard assessment.

A promising strategy for enhancing fire resistance of steel structure: a composite thermoplastic polyurethane sheet adhered to steel plate

It is an effective passive fire protection method for the steel structure by painting fireproof coatings. Here, a feasible strategy for enhancing the fire resistance of steel structures is proposed. Specifically, a kind of adhesive composite sheet based on thermoplastic polyurethane (TPU), ammonium polyphosphate (APP), polyhedral oligomeric octaphenylsilsesquioxane (OPS), titanium dioxide (TiO2) and sodium silicate was constructed and named as Sheet-Ti/Na. The as-prepared Sheet-Ti/Na exhibited excellent flame retardancy and smoke suppression performance. In addition, the Sheet-Ti/Na can firmly adhere to the steel plate through hot pressing and adhesive bonding methods, acting as a non-traditional fireproof “coating”. This feasible coating method can effectively enhance the fireproof and thermal insulation of the steel plates under the action of the hydrocarbon fire at about 1100 ℃. After testing, the char layer of Sheet-Ti/Na can still firmly adhere to the steel plate without any detachment or cracking. Finally, a ceramic-like reaction among TiO2, APP, OPS and sodium silicate to generate pyrophosphates (TiP2O7 and SiP2O7) was clarified. The thermal insulation, flame retardancy and smoke suppression mechanisms of the Sheet-Ti/Na system also were stated. This work offers a promising strategy for rapidly and efficiently preparing fireproof and thermal insulation “coatings” for steel structures.

Fire Protection of Steel Structures of Oil and Gas Facilities: Multilayer, Removable, Non-Combustible Covers

Fire protection is required to protect metal structures of oil and gas facilities from fires. Such fire protection should provide high fire resistance limits: 60, 90, 120 and more minutes. Specialists of LLC “RPC PROMIZOL ” developed a multilayer, removable type of fire protection made of superfine basalt fibre and ceramic materials for operation in Arctic conditions. Five experimental studies were carried out in standard and hydrocarbon fire regimes. The fire protection effectiveness of the products for I20 beams without load was obtained: a 50 mm thick coating provided 130 min of a standard fire regime; a 15 mm thick coating provided 60 min. The 15 mm thick coating provided 30 min of a hydrocarbon fire regime and the 50 mm thick coating provided 93 min of a hydrocarbon fire regime. The I40 beam under a load of 19.9 tf showed an R243 for the standard fire regime. The coefficients of effective thermal conductivity and specific heat capacity of fire-retardant compositions were determined by solving the inverse heat conduction problem. The problem was solved by modelling using the QuickField 7.0 software package, which implements FEM. Modelling showed that for obtaining the fire resistance limit R120 under the standard fire regime for the sample steel structure from an I40 beam, it is enough to apply fire protection with a thickness of 25 mm instead of 50 mm, which agrees with the experimental data. For the hydrocarbon regime, it is predicted that R120 can be obtained at a thickness of 45 mm instead of 50 mm.

Experimental and Numerical Studies on the Efficacy of Water Mist to Suppress Hydrocarbon Fires in Enclosures

Fire is one of the most undesirable events onboard a ship. The engine room is one of the most critical spaces in the ship in terms of fire protection, as it includes machinery, hydrocarbon fuel systems, and different electrical equipment. With the phasing out of Halon 1301 as a fire suppressant over recent decades, there has been an intensive effort to explore the efficacy of water-mist spray in mitigating fires within machinery spaces. This exploration entails a comprehensive investigation through experimental and simulation studies aimed at identifying suppression mechanisms and evaluating their effectiveness. While experimental setups typically encompass measurements of gas temperature, thermal radiation heat flux, oxygen concentration, and fire extinction time, limited attention has been paid to quantifying the heat release rate (HRR), a crucial indicator of fire magnitude. Furthermore, research into shielded fire scenarios remains sparse, despite their significance in maritime fire dynamics. Addressing shielded fires with water mist proves particularly challenging due to the potential obstruction impeding the direct interaction between the fire source and the water droplets. In the existing literature, most of the computational fluid dynamics (CFD) modelling of fires and suppression was performed using a Fire Dynamics Simulator (FDS). Alternate studies were performed using FireFOAM. and very few employed FLUENT and other analogous software codes. In the majority of reported computational studies, the determination of HRR was typically relied upon for its calculation derived from the measured data of fuel mass loss rate. Moreover, certain studies were undertaken for numerical simulations without conducting thorough model validation, either by omitting validation altogether or solely validating against dry fire experiments (i.e., without water-mist suppression). This critical review of the literature has identified several notable research gaps in the context of extinguishing hydrocarbon fires utilising water-mist spray, warranting further investigations. Additionally, this review paper highlights recent advancements in both experimental and numerical investigations pertaining to the efficacy of water-mist fire-suppression systems in enclosed spaces regarding hydrocarbon fires.

A Model generation method and iteration algorithm for optimising fire protection thickness

With temperatures rising above 1000 °C within 5 min, hydrocarbon fire causes rapid strength degradation of structural steel members. It is among the most dangerous hazards, such as boiling liquid expanding vapour explosion (BLEVE) in the oil and gas industry. Intumescent coating as passive protection is widely adopted to prevent the steel structure from material property reduction. However, when optimising fire protection with heat transfer simulation, repetitive modelling work and lacking recalculation principle hinder productivity improvement. This method is developed to generate steel beam models and provides an effective algorithm to optimise coating thickness considering the temperature of a specific region. The main functions of the method include:•Providing section dimensions, initial insulation thickness, target temperature and heating time, temperature allowance and mesh size as variables.•Automatically generating the Abaqus steel beam model under 3-side heating conditions.•Effective iteration algorithm to modify fire protection thickness: test containing 38 Universal beam sections with a 5 °C allowance below target shows that 55.2% were completed within five iterations and 76.3% were completed within eight iterations.

Analysis of the Heating of Steel Structures During Fire Load

During the preparation of our article, we present in detail the changes in the thermotechnical parameters of carbon steel and corrosion resistance during fire. After that, we present in detail the calculation of the heating of steel structures without fire protection. We feel this is important because it is not possible to provide stainless steel with fire protection for aesthetic reasons, and it is also not typical for thin-walled galvanized structures. We also present the calculation of structures with fire protection in detail and present the background for editing commonly used nomograms. Such a nomogram is also available in the literature, but it can be considered true with significant simplifications. During the practical planning, the applied fire protection regulations were highly standardized. Realizing that there is no design nomogram for these types of solutions, we created and published them in our article. The advantage of these is that the applicable design can also be found as the optimum of the designs considered to be potentially good. With this solution, we can save time during planning, and we can also get a more cost-effective solution for the fire protection cover. The advantage of the presented method is that, if required, the editing of the nomograms can be extended to other designs by knowing the material characteristics and the layer thickness. Another option of the presented method is that the solution can also be applied to special fire loads, and nomograms can be produced for them as well (e.g., hydrocarbon fires). Doi: 10.28991/ESJ-2024-08-01-01 Full Text: PDF

ДОСЛІДЖЕННЯ ВОГНЕСТІЙКОСТІ ПОКРИТТЯ РЕАКТИВНОГО ТИПУ В УМОВАХ ВУГЛЕВОДНЕВОЇ ПОЖЕЖІ

The purpose of the study is to compare the efficiency of reactive fire protection coatings in modelling scenarios of standard and hydrocarbon fires. Methodology. Fire tests were carried out in a small-scale furnace, as regulated by DSTU EN 16623:2015. The linear coefficient of swelling K was determined in accordance with DSTU-N P B V.1.1-29:2010, and the strength of the char layer was measured using a ST-2 structurometer. The chemical structure of the thermolysis products of the fireproof coatings was studied by IR spectroscopy. Results. The study proposes an experimental protocol for assessing the strength of swollen coatings on steel plates under the influence of a standard and hydrocarbon fire. The evaluation method is based on monitoring the physical integrity and mechanical stability of the char-insulating layer formed from the reactive coating under high temperatures. It has been found that the reactive-type coating under the influence of a standard and hydrocarbon fire forms heat-protective char layers, the degree of swelling, mechanical strength and adhesion of which to the metal plate are proportional and differ on average by up to 10 %. It has been concluded that the studied coating Ammokote MW-120 can be used for fire protection of steel structures operated under potential conditions of hydrocarbon fire. Scientific novelty. The study proposes a simple and reliable method for assessing the possibility of using reactive-type coatings for fire protection of metal structures intended for use and certified for standard fire conditions in hydrocarbon fires. Pactical significance is to expand the scope of application of Ammokote MW-120 coating for fire protection of steel structures under the influence of standard and hydrocarbon fires. Keywords: fire protection of steel structures, hydrocarbon fire, intumescent coating, swelling coefficient.

Evaluation of the performance of slurry infiltrated fibre concrete slabs exposed to hydrocarbon fire

Evaluation of the performance of slurry infiltrated fibre concrete slabs exposed to hydrocarbon fire

Temperature Distribution Curve Analysis on Concrete through LS-DYNA

The development and importance of tunnels are increasing worldwide, and countries like Korea, where about 70% of the total land is covered with mountain regions, need more tunnel constructions to connect different routes of roads for safe and efficient transport. This study applied fire to the 200 mm × 200 mm × 200 mm concrete specimens, similar to the Rijkswaterstaat (RWS) fire, through an electric furnace. Thermocouples were placed inside the specimens to analyze the temperature during the occurrence of fire. Experimental and simulation thermal analysis during the occurrence of fire was analyzed. The experimental temperature at different depths agreed with the simulation results. Different international fire curves were applied to study the temperature inside the concrete through simulation by LS-DYNA. Concrete with different thicknesses of fireproof board was analyzed through simulation, and using fireproof board reduces the inside temperature during fire occurrence. Among the studied international fire curves, modified hydrocarbon fire curves had a high-temperature effect on concrete.

Investigating the fire resistance of corrugated steel columns

This research paper focuses on investigating the fire resistance of axially restrained Corrugated Plate Steel columns (CRG) exposed to hydrocarbon fire conditions. Key parameters, including corrugation depth, plate thickness, axial load percentage, and column length, were analyzed to assess their impact on the fire resistance performance of CRG columns. A comprehensive analysis involving 80 finite element (FE) models was conducted using ABAQUS software. The analysis process encompassed studying temperature distribution within the columns, observing buckling modes, and determining the durations of buckling and failure fire resistance. The adopted FE model has been verified by comparing it to experimental data presented in the relevant literature. Findings reveal that corrugated CRG columns exhibit superior resistance to buckling and structural failure compared to circular cross-section columns. Corrugation depth minimally affects fire resistance but influences axial deformation and generated axial force due to increased structural stiffness. Increasing plate thickness improves fire resistance, particularly at lower axial load levels, while increasing axial load percentage decreases fire resistance. Doubling the column length has no significant effect on fire resistance, but columns with smaller plate thicknesses exhibit lower resistance under high axial load conditions. These insights inform the design and construction of CRG columns in structures exposed to hydrocarbon fire risks, aiding in enhancing fire safety and performance.

Assessment of critical parameters affecting the behaviour of bearing reinforced concrete walls under fire exposure

PurposeThis research paper aims to investigate reinforced concrete (RC) walls' behaviour under fire and identify the thermal and mechanical factors that affect their performance.Design/methodology/approachA three-dimensional (3D) finite element (FE) model is developed to predict the response of RC walls under fire and is validated through experimental tests on RC wall specimens subjected to fire conditions. The numerical model incorporates temperature-dependent properties of the constituent materials. Moreover, the validated model was used in a parametric study to inspect the effect of the fire scenario, reinforcement concrete cover, reinforcement ratio and configuration, and wall thickness on the thermal and structural behaviour of the walls subjected to fire.FindingsThe developed 3D FE model successfully predicted the response of experimentally tested RC walls under fire conditions. Results showed that the fire resistance of the walls was highly compromised under hydrocarbon fire. In addition, the minimum wall thickness specified by EC2 may not be sufficient to achieve the desired fire resistance under considered fire scenarios.Originality/valueThere is limited research on the performance of RC walls exposed to fire scenarios. The study contributed to the current state-of-the-art research on the behaviour of RC walls of different concrete types exposed to fire loading, and it also identified the factors affecting the fire resistance of RC walls. This guides the consideration and optimisation of design parameters to improve RC walls performance in the event of a fire.

Thermal Characteristics of Epoxy Fire-Retardant Coatings under Different Fire Regimes

Different systems of fire protection coatings are used to protect the metal structures of stories and trestles at oil and gas facilities from low (when filling cryogenic liquids) and high temperatures (in case of the possible development of a hydrocarbon fire regime). This paper presents the results of experiments of fireproof coatings on an epoxy binder after the simulation of a liquefied hydrocarbons spill and subsequent development of a hydrocarbon fire regime at the object of protection and exposure of structures to a standard fire regime. According to the experimental results, the temperatures on the samples at the end of the cryogenic exposure were determined and the time from the beginning of the thermal exposure to the limit state of the samples at a hydrocarbon and standard temperature fire regime was determined. As a result, temperature–time curves in the hydrocarbon and standard fire regimes were obtained, showing good convergence with the simulation results. The solution of the inverse task of heat conduction using finite element modeling made it possible to determine the thermophysical properties of the formed foam coke at the end of the fire tests of steel structures with intumescent coatings. It was determined that an average of 12 mm of intumescent coating thickness is required to achieve a fire protection efficiency of 120 min and for the expected impact of the hydrocarbon fire regime, the coating consumption should be increased by 1.5–2 times compared to the coating consumption for the standard regime.

Reinforced Concrete Columns Insulated by Different Gypsum Layers Exposed to 900°C One Side Fire Flame

This study investigated the effect of high-temperature fire flame on reinforced concrete columns coated with a layer of gypsum insulation. Six samples were cast and cured in a hot water bath at 67°C, covered on one side by 10 and 20 mm thick layers of gypsum plaster. The samples were exposed to a 900°C fire flame in a hydrocarbon fire furnace for one and two hours. The results showed that the gypsum plaster layer prevented a high-temperature rise within the core of the column. The differences between all gypsum-coated columns varied compared to those of the reference samples. The gypsum-coated columns had reduced axial displacements and no spalling and visible cracks on their faces. The improvement in the compressive strength of concrete will be discussed in a future paper. This study was carried out following ACI-318 and ASTM C1529.

Behavior of steel box bridge girders subjected to hydrocarbon fire and bending-torsion coupled loading

This paper presents an experimental together with numerical investigation on behavior of steel box bridge girders under hydrocarbon (HC) fire and bending-torsion coupled loading conditions. Four test bridge girders fabricated utilizing single-box configured with twin-chamber supporting thin concrete slabs, taking into consideration sectional features and loading methods, were simultaneously subjected to HC fire exposure and bending-torsion coupled loading to analyze thermal and structural response. A numerical model established through program ANSYS, validated dependent on measured data generated from fire tests, was used to conduct a parametric analysis. Results show that significant discrepancies of temperature occur in mid-web and side-web of test bridge girders exposed to HC fire. Steel top flange has a significant influence on heat accumulation and transfer inside steel box, escape of water vapour in concrete slab and also fire resistance of steel box bridge girders. Deflection difference in transverse section of test bridge girders subjected to bending-torsion coupled loading gradually become predominant with fire exposure time. Test bridge girders without steel top flange experience a wide longitudinal crack in concrete slabs instead of excessive flexural deflection through entire fire exposure duration. Increasing longitudinal stiffeners in mid-web and bottom flange can effectively enhance fire resistance of steel box bridge girders. Timely evacuation of applied loads enforced on bridge girders during fire exposure can greatly delay deflection progression. The post-fire residual bearing capacity in test bridge girders can recover more than 80 % of initial bearing capacity after HC fire exposure. The experienced maximum temperature and fire exposure time has a predominant influence on post-fire recovery ability of steel box bridge girders under ventilation cooling conditions.

Analysis of hydrocarbon fire-exposed cold-formed steel columns

This study examines the fire behavior of cold-formed steel (i.e., CFS) columns exposed to hydrocarbon fire. Using ABAQUS numerical software, the heat transfer, and structural responses of CFS columns were simulated under hydrocarbon fire and axial compression. The research introduces two fire resistance levels: buckling time resistance (i.e., BTR, linked to maximum generated axial compression) and failure time resistance (i.e., FTR, at zero-axial generated force). Validation of the finite element model is achieved through comparison with the testing data reported in the literature. A parametric analysis explores key factors: the axial load level (α), slenderness ratio (λ), radius-to-thickness ratio (Rt), and the failure mode. Findings indicate significant impacts of α and Rt on CFS column behavior in hydrocarbon fire exposure. Increasing α by 60% decreases fire resistance by 30% and increases deformation rate by 63% on average. Adjustments in Rt proportionally affect both buckling and failure time resistance to approximately the same scale. In contrast, while λ has minimal effect on buckling time resistance, it does influence failure time resistance.