Problems of calculation of classes and sizes of explosive zones round external equipments

 

Oleg Kulakov

National University of Civil Defence of Ukraine

http://orcid.org/0000-0001-5236-1949

 

Albert Katunin

National University of Civil Defence of Ukraine

http://orcid.org/0000-0003-2171-4558

 

Elena Lyashevska

National University of Civil Defence of Ukraine

http://orcid.org/0000-0002-1469-4141

 

DOI: https://doi.org/10.52363/2524-0226-2021-33-13

 

Keywords: explosive zone, external equipments, explosive environment, hypothetical volume, wind speed, time of existence

 

Abstract

Found out features of determination of classes and sizes of explosive zones that is created by explosive gas atmospheres round external equipments. National classification comes true by two methods, one of that is determined, and other - by a calculation. Explosive gas atmospheres round external equipments can form the explosive zones of classes 0, 1, 2. At application of calculation method initial parameters are climatic terms, properties are dangerous substances, degree of source and  level of ventilation. Intensity of source of liquid is determined, settle accounts hypothetical volume of explosive environment, compared that to the fixed value of general volume that is ventilated. An of hypothetical volume and time of existence of explosive environment depend on speed of wind on a hyperbolical law.  For example of the external equipments it is shown as an untight muff of above - ground gas pipeline of natural gas, that speed of wind is substantial influences on the size of hypothetical volume of explosive environment. At of speed that answers quiet wind after a scale of Beaufort, round the external equipment the explosive zone of class is created 1. At of speed that answers easy wind after a scale of Beaufort, round the external equipment the explosive zone of class is created 2. If decline of ambient temperature results in diminishing of size of hypothetical volume of explosive environment. Intensity of source of hazardous substance substantially influences on the class of explosive zone. For every type of hazardous substance it is necessary to determine the maximum value of intensity of source, higher that the explosive zone of class takes place 1, and below is an explosive zone of class 2. Time of existence of explosive environment does not depend on ambient and intensity of source temperature and quickly diminishes with the increase of speed of wind.

 

References

  1. HIS Markit Standards Store. (2021). International Electrotechnical Commis-sion (IEC). Available online: https://global.ihs.com/standards.cfm? publisher=IEC.
  2. National Fire Protection Association (NFPA). (2021). Retrieve from https://www.nfpa.org
  3. IEC 60079-10-1. (2020). Explosive atmospheres – Part 10-1: Classification of areas – Explosive gas atmospheres. 226. Retrieve from https://webstore.iec.ch/publication/63327
  4. IEC 60079-10-2. (2015). Explosive atmospheres – Part 10-2: Classification of areas – Explosive dust atmospheres. 92. Retrieve from https://webstore.iec.ch/publication/623
  5. ANSI/NFPA 70. (2020). National Electrical Code. Retrieve from https://www.nfpa.org/codes-and-standards/all-codes-and-standards/list-of-codes-and-standards/detail?code=70
  6. Tommasini, R., Pons, E., Palamara, F. (2013). Area classification for ex-plosive atmospheres: Comparison between European and North American approaches. Industry Applications Society 60th Annual Petroleum and Chemical Industry Conference, Chicago, IL, USA, 1–7. doi: 10.1109/PCICon.2013.6666015
  7. Mihoub, Z., Ouslati, A., Smadi, H. (2020). Determination and Classification of Explosive Atmosphere Zones While Considering the Height of Discharges. Journal of Faulure Analysis and Prevention, 20, 503–512. doi: 10.1007/s11668-020-00851-8
  8. Geng, J. (2016). Innovation Driven by Human and Organizational Factors (HOF) in Risk Assessment Methodologies and Standards: ATEX (Explosive Atmos-phere) Risk Assessment Application. Ph.D. Thesis, Polytechnic University of Turin. doi: 10.6092/polito/porto/2642505
  9. Kulakov, O. V., Katunin, A. M. (2020). Vply`v venty`lyaciyi na vy`znachennya klasu i rozmiru vy`buxonebezpechnoyi zony`, shho stvoryuyet`sya paropovitryany`m vy`buxonebezpechny`m seredovy`shhem u pry`mishhenni. Prob-lemyi pozharnoy bezopasnosti, 47, 65–70. Retrieve from https://nuczu.edu.ua/images/topmenu/science/zbirky-naukovykh-prats-ppb/ppb47/10.pdf
  10. Benintendi, R. (2010). Turbulent jet modelling for hazardous area classifica-tion. Journal of Loss Prevention in the Process Industries, 23, 373–378. doi: 10.1016/j.jlp.2009.11.004
  11. Webber, D., Ivings, M., Santon, R. (2011). Ventilation theory and dispersion modelling applied to hazardous area classification. Journal of Loss Prevention in the Process Industries, 24(5), 612–621. doi: 10.1016/ j.jlp.2011.04.002
  12. Lauri, R. (2016). Atmosfere potenzialmente esplosive: metodologia di valutazione della distanza pericolosa derivante da emissioni di compressori. La Termotecnica, 5, 51–54. Retrieve from https://verticale.net/metodologia-di-valutazione-della-distanza-pericolosa-9553.
  13. Lauri, R. (2018). A Methodological Approach for the Characterization of Hazardous Zones due to Potentially Explosive Atmospheres: a Case Study. Chemical engineering transactions, 67, 169–174. doi: 10.3303/ CET1867029
  14. Liu, Y., Liu, Z., Wei, J., Lan, Y., Yang, S., Jin, T. (2021). Evaluation and prediction of the safe distance in liquid hydrogen spill accident. Process Safety and Environmental Protection, 146, 1–8. doi: 10.1016/j.psep.2020.08.037
  15. Jespen, T. (2016). ATEX – Explosive Atmospheres. Springer Series in Relia-bility Engineering, 197. doi: 10.1007/978-3-319-31367-2
  16. NPAOP 40.1-1.32-01. (2013). Pravy`la budovy` elektroustanovok. 117. Re-trieve from https://dnaop.com/html/1692/doc-НПАОП_40.1-1.32-01
  17. IEC 60050-426. (2020). International Electrotechnical Vocabulary (IEV) – Part 426: Equipment for Explosive atmospheres. 430. Retrieve from https://webstore.iec