Oil and gas fields at pad wells: modeling of fire resistance of steel trestle structures

Introduction. Russian standards provide deterministic indicators of the required fire resistance of load-bearing structures of industrial facilities. Changes in CP 4.13130 are based on the American standard API 2218, where a probabilistic approach is assumed for determining fire exposure zones and required fire resistance limits. However, this approach is not used at oil industry facilities due to the lack of a methodology for determining the impact zones for hydrocarbon combustion.

Aims and objectives. The aim of this study is to determine the actual fire resistance limits of steel overpasses executing indicated scenarios in order to obtain the dependence of fire resistance of structures on the distance to the source of fire. Objectives of the study also include developing field fire models according to the design documentation; determination of the zones exposed to critical temperature; identifying the fire resistance of structures under different fire regimes.

Methods. The initial data was the design documentation of three oil fields with cluster arrangement of wells. The most dangerous and probable oil or gas spill fire scenarios were modelled for each field. Models of raised oil and gas pipelines were developed using Revit software. Fire hazard spreading was modelled by the method of field fire simulation using PyroSim.

Results. The study found actual fire resistance limits of pipelines of three fields, along with the sizes of fire impact zones, where fire protection of structures is required. Fire protection to ensure fire resistance R60 is required at less than 10.7 m at a source of fire of 305.24 MW; at 38.6 MW the critical temperature is reached in the radius of as low as 3 m.

Conclusions. In a “real” fire regime, structures may have higher fire resistance limits than required in the regulations. Modelling and calculation of fire resistance allows to determine the need for fire protection for each zone of fire exposure, not only within a radius of up to 12 meters. Scientific research in this area will make it possible to develop new normative documents for determining the fire exposure zones and fire resistance limits of exterior structures.

1. Khasanov I.R., Gravit M.V., Kosachev A.A., Pekhotikov A.V., Pavlov V.V. Harmonization of European and Russian regulatory documents establishing general requirements for fire-resistance test methods of building constructions and the use of temperature curves that take into account real fire conditions. Pozharovzryvobezopasnost/Fire and Explosion Safety. 2014; 23(3):49-57. EDN SFOCFF (rus).

2. Abramov I.V., Gravit M.V., Gumerova E.I. Increase in the fire resistance limits of ship and building structures with hydrocarbon fire. Gas Industry Magazine. 2018; 5:106-115. URL: https://cyberleninka.ru/article/n/povyshenie-predelov-ognestoykosti-sudovyh-i-stroitelnyh-konstruktsiy-pri-uglevodorodnom-temperaturnom-rezhime (accessed: 27.03.2024). (rus).

3. Klementev B., Kalach A., Gravit M. A comparative analysis of the requirements of Russia and the United States to the fire resistance of building structures of oil refineries and petrochemical plants. Pozharovzryvobezopasnost/Fire and Explosion Safety. 2021; 30(5):5-22. DOI: 10.22227/0869-7493.2021.30.05.5-22 URL:ravnitelnyy-analiz-­trebovaniy-rossii-i-ssha-k-ognestoykosti-stroitelnyh-konstruktsiy-neftepererabatyvayuschih-i-neftehimicheskih (accessed: 27.03.2024). (rus).

4. Dehkordi M.K., Behnam B., Pirbalouti R.G. Probabilistic fire risk analysis of process pipelines. Journal of Loss Prevention in the Process Industries. 2022; 80:104907. DOI: 10.1016/j.jlp.2022.104907

5. Kashi E., Bahoosh M. Jet fire assessment in complex environments using computational fluid dynamics. Brazilian Journal of Chemical Engineering. 2020; 37(1):203-212. DOI: 10.1007/s43153-019-00003-y

6. Shebeko A.Yu. Estimation of required fire resistance limits of bearing structures of refinery platforms and pipe racks. Pozharnaya bezopasnost/Fire Safety. 2019; 1:103-107. EDN YZZZML (rus).

7. Shi J., Dao J., Jiang L., Pan Z. Research on IFC- and FDS-Based information sharing for building fire safety analysis. Advances in Civil Engineering. 2019; 2019(1). DOI: 10.1155/2019/3604369

8. Rengel B., Mata C., Pastor E., Casal J., Planas E. A priori validation of CFD modelling of hydrocarbon pool fires. Journal of Loss Prevention in the Process Industries. 2018; 56:18-31. DOI: 10.1016/j.jlp.2018.08.002

9. Shebeko Yu.N., Zuban A.V., Shebeko A.Yu. An evaluation of an actual fire resistance limit of non-protected steel structures for different temperature regimes of fires. Pozharovzryvobezopasnost/Fire and Explosion Safety. 2019; 28(6):29-34. DOI: 10.18322/PVB.2019.28.06.29-34 (rus).

10. Gravit M., Dmitriev I., Shcheglov N., Radaev A. Oil and gas structures: forecasting the fire resistance of steel structures with fire protection under hydrocarbon fire conditions. Fire. 2024; 7:173. DOI: 10.3390/fire7060173

11. Shebeko A.Yu., Shebeko Yu.N., Zuban A.V. The calculation of required fire resistance limits for engineering structures of technological pipe racks at oil and gas processing plants on the basis of an evaluation of the time needed for personnel evacuation and rescue in case of fire. Pozharovzryvobezopasnost/Fire and Explosion Safety. 2021; 30(5):58-65. DOI: 10.22227/0869-7493.2021.30.05.58-65 (rus).

12. Li Lifeng, Luo Jinheng, Wu Gang, Li Xinhong, Ji Nan, Zhu Lixia. Impact assessment of flammable gas dispersion and fire hazards from LNG tank leak. Mathematical Problems in Engineering. 2021; 2021:1-15. DOI: 10.1155/2021/4769552

13. Santos F.da, Landesmann A. Thermal performance-based analysis of minimum safe distances between fuel storage tanks exposed to fire. Fire Safety Journal. 2014; 69:57-68. DOI: 10.1016/j.firesaf.2014.08.010

14. Tong S.-jiao, Wu Z.-zhi, Wang R.-jun, Wu H. Fire risk study of long-distance oil and gas pipeline based on QRA. Procedia Engineering. 2016; 135:368-374. DOI: 10.1016/j.proeng.2016.01.144

15. Pio G., Carboni M., Iannaccone T., Cozzani V., Salzano E. Numerical simulation of small-scale pool fires of LNG. Journal of Loss Prevention in the Process Industries. 2019; 61:82-88. DOI: 10.1016/j.jlp.2019.06.002.

16. Lim J.W., Baalisampang T., Garaniya V., Abbassi R., Khan F., Ji J. Numerical analysis of performances of passive fire protections in processing facilities. Journal of Loss Prevention in the Process Industries. 2019; 62:103970. DOI: 10.1016/j.jlp.2019.103970

17. Manco M.R., Vaz M.A., Cyrino J.C.R., Landesmann A. Evaluation of localized pool fire models to predict the thermal field in offshore topside structures. Journal of the Brazilian Society of Mechanical Sciences and Engineering. 2020; 42(12). DOI: 10.1007/s40430-020-02694-8

18. Chandrasekaran S., Pachaiappan S. Numerical analysis and preliminary design of topside of an offshore platform using FGM and X52 steel under special loads. Innovative Infrastructure Solutions. 2020; 5(3). DOI: 10.1007/s41062-020-00337-4

19. Shebeko A.Yu. Assessment of equivalent fire duration for building structures based on compartment fire modeling. Pozharnaya bezopasnost’/Fire Safety. 2015; 1:31-39. (rus).