Advertisement

Experimental investigation of effects of variation in heating rate, temperature and heat flux on fire properties of a non-charring polymer

  • Ariza S. Abu-Bakar
  • Marlene J. Cran
  • Khalid A. M. Moinuddin
Article

Abstract

During fire, charring and non-charring polymers undergo reactions in the solid phase (pyrolysis) and in the gas phase (combustion). These reactions can be modelled using computational fluid dynamics-based fire modelling for the prediction of fire growth and spread. Given that many fire properties vary with temperature including heating rate and radiation flux, improvements in fire simulations can be made by accounting for these variations. This study characterizes the fire properties of the non-charring synthetic polymer poly(methyl methacrylate) (PMMA) for coupled pyrolysis and combustion simulation. Under pyrolysis, the heat of reaction of PMMA varies with heating rate due the change in residence time facilitating volatilization at any given temperature, particularly at higher heating rates. As a result, the volatiles are formed when the sample has reached higher temperature and therefore more heat flow is needed to assist this process at higher heating rates. Similarly, combustion parameters are also found to vary with the incident radiation flux; however, the variation is relatively minimal. In this study, thermal conductivity and specific heat capacity did not vary with temperature for PMMA.

Keywords

Pyrolysis Combustion Chemical kinetics Heat of reaction Heating rate Effective heat of combustion 

List of symbols

A

Pre-exponential factor, s−1

A

Area under the peak, m2

AT

Area under the curve, m2

Cp

Specific heat capacity, J kg−1 °C−1

Ea

Activation energy, kJ min−1

EHoC

Effective heat of combustion, kJ kg−1

HoR

Heat of reaction, kJ kg−1

HRR

Heat release rate, kW

\(k\)

Conductivity, W m−1 °C−1

MLR

Mass loss rate, m2 kg−1

MC

Moisture content, %

mi

Sample mass at the approximation

\(\dot{m^{\prime\prime}}\)

Mass loss rate per unit area, kg m−2 s−1

n

Reaction order

\(\dot{q}_{\text{c}}^{{\prime \prime }}\)

Convective heat flux, kW m−2

\(\dot{q}_{\text{r}}^{{\prime \prime }}\)

Radiative heat flux, kW m−2

R

Universal gas constant, J kg−1 mol−1 K−1

SEA

Specific extinction area, m2 kg−1

s

Solid

T

Temperature, °C or K

T1

Peak 1 integration temperature, °C

T2

Peak 2 integration temperature, °C

t

Time, s

xi

Mass loss fraction

Y

Weight fraction of conversion

yi

Fraction of ith gaseous products yield

dY/dT

Pyrolysis rate

dt/dT

Heating rate

w

Instantenous sample mass, mg

wi

Initial sample mass, mg

wf

Final sample mass, mg

wfc

Final sample mass (cone), mg

wic

Initial sample mass (cone), mg

β

dT/dt or heating rate, K s−1

ΔE

Heat flow into DSC sample, mW

ΔHDSC

Normalized enthalpy, kJ kg−1

ΔH

Heat of reaction, kJ kg−1

ΔHR

Heat of reaction in fire model, kJ kg−1

ΔHcon

Normalized HoR, kJ kg−1

ΔHenh

Enhanced HoR, kJ kg−1

ρ

Density, kg m−3

νs

Yield of solid residue, %

Notes

Acknowledgements

The authors wish to acknowledge the technical and financial assistance provided by Omnii Pty Ltd, Xtralis and Scientific Fire Services. The authors also acknowledge stimulating discussions with Dr. Yun Jiang of Xtralis. Ariza S. Abu-Bakar was a Ph.D. candidate at Victoria University funded by Universiti Sains Malaysia and currently employed by the same university.

References

  1. 1.
    McGrattan K, et al. Fire dynamics simulator (version 6.2): user’s guide. Gaithersburg: National Institute of Standard and Technology; 2015.Google Scholar
  2. 2.
    Abu-Bakar AS, Moinuddin KAM. Effects of variation in heating rate, sample mass and nitrogen flow on chemical kinetics for pyrolysis. In: 18th Australasian fluid mechanics conference. Launceston, TAS; 2012.Google Scholar
  3. 3.
    Font R, et al. Kinetics of pyrolysis and combustion of pine needles and cones. J Anal Appl Pyrol. 2009;85(1):276–86.CrossRefGoogle Scholar
  4. 4.
    Gai C, Dong Y, Zhang T. The kinetic analysis of the pyrolysis of agricultural residue under non-isothermal conditions. Bioresour Technol. 2013;127:298–305.CrossRefPubMedGoogle Scholar
  5. 5.
    Jiang Y. Decomposition, ignition and flame spread on furnishing materials. Melbourne: CESARE, Victoria University; 2006.Google Scholar
  6. 6.
    Matala A, Hostikka S, Mangs J. Estimation of pyrolysis model parameters for solid materials using thermogravimetric data. Fire Saf Sci. 2008;9:1213–23.CrossRefGoogle Scholar
  7. 7.
    Starink MJ, Gregson PJ. A quantitative interpretation of DSC experiments on quenched and aged SiCp reinforced 8090 alloys. Scr Metall Mater. 1995;33(6):893–900.CrossRefGoogle Scholar
  8. 8.
    American Society for Testing and Materials. ASTM 1354-04a, standard test method for heat and visible smoke release rates for materials and products using an oxygen consumption calorimeter. West Conshohocken, PA: ASTM International; 2004. www.astm.org. Accessed 03 Feb 2010.
  9. 9.
    Shi L, Chew MYL. A review of fire processes modeling of combustible materials under external heat flux. Fuel. 2013;106:30–50.CrossRefGoogle Scholar
  10. 10.
    Xu Q, et al. Discuss the heat release capacity of polymer derived from microscale combustion calorimeter. J Therm Anal Calorim. 2018;133(1):649–57.CrossRefGoogle Scholar
  11. 11.
    Xu Q, et al. A PMMA flammability analysis using the MCC. J Therm Anal Calorim. 2016;126(3):1831–40.CrossRefGoogle Scholar
  12. 12.
    Pau DSW. A comparative study on combustion behaviours of polyurethane foams with numerical simulations using pyrolysis models. Christchurch: Civil and Natural Resources Engineering, University of Canterbury; 2013.Google Scholar
  13. 13.
    Viswanath SG, Gupta MC. Estimation of nonisothermal kinetic parameters from a TG curve by the methods of overdetermined system and inflection point. Thermochim Acta. 1996;285(2):259–67.CrossRefGoogle Scholar
  14. 14.
    Wadhwani R, et al. Kinetics of pyrolysis of litter materials from pine and eucalyptus forests. J Therm Anal Calorim. 2017;130(3):2035–46.CrossRefGoogle Scholar
  15. 15.
    McGrattan K, Forney G. Fire dynamics simulator (version 4) user’s guide. 4th ed. Washington: US Government Printing Office; 2006.CrossRefGoogle Scholar
  16. 16.
    Gustafsson SE. Transient plane source techniques for thermal conductivity and thermal diffusivity measurements of solid materials. Rev Sci Instrum. 1991;62(3):797–804.CrossRefGoogle Scholar
  17. 17.
    Sibulkin M. Heat of gasification for pyrolysis of charring materials. In: Proceedings of the first international symposium on fire safety science. Boca Raton: CRC Press; 1986.Google Scholar
  18. 18.
    Kodur VKR, Harmathy TZ. Properties of building materials. In: DiNenno PJ, editor. SFPE handbook of fire protection engineering. 3rd ed. Berlin: Springer; 2002. p. 155–81.Google Scholar
  19. 19.
    Huffman R, Pan W-P. Combining DSC and TG data for measuring heats of reaction. Thermochim Acta. 1990;166:251–65.CrossRefGoogle Scholar
  20. 20.
    Rath J, et al. Heat of wood pyrolysis. Fuel. 2003;82(1):81–91.CrossRefGoogle Scholar
  21. 21.
    Abu-Bakar AS. Characterization of fire properties for coupled pyrolysis and combustion simulation and their optimised use. Melbourne: College of Engineering and Science, Victoria University; 2015.Google Scholar
  22. 22.
    Fang MX, et al. Kinetic study on pyrolysis and combustion of wood under different oxygen concentrations by using TG-FTIR analysis. J Anal Appl Pyrol. 2006;77(1):22–7.CrossRefGoogle Scholar
  23. 23.
    Gao N, et al. TG–FTIR and Py–GC/MS analysis on pyrolysis and combustion of pine sawdust. J Anal Appl Pyrol. 2013;100:26–32.CrossRefGoogle Scholar
  24. 24.
    Luche J, et al. Characterization of thermal properties and analysis of combustion behavior of PMMA in a cone calorimeter. Fire Saf J. 2011;46(7):451–61.CrossRefGoogle Scholar
  25. 25.
    American Society for Testing and Materials. ASTM E2160-04 standard test method for heat of reaction of thermally reactive materials by differential scanning calorimetry. West Conshohocken, PA: ASTM International; 2004. www.astm.org. Accessed 03 Feb 2010.
  26. 26.
    Hostikka S. 2012. (Personal Communication)Google Scholar
  27. 27.
    Matala A. Estimation of solid phase reaction parameters for fire simulation. Espoo: Faculty of Information and Natural Sciences, Helsinki University of Technology; 2008.Google Scholar
  28. 28.
    Li K-Y, et al. Pyrolysis of medium-density fiberboard: optimized search for kinetics scheme and parameters via a genetic algorithm driven by Kissinger’s method. Energy Fuels. 2014;28(9):6130–9.CrossRefGoogle Scholar
  29. 29.
    Zhang Z et al. Effect of temperature and heating rate in pyrolysis on the yield, structure and oxidation reactivity of pine sawdust biochar. In: Chemeca 2013: challenging tomorrow. Barton, ACT: Engineers Australia; 2013. p. 863–9.Google Scholar
  30. 30.
    Kim S-S, et al. Pyrolysis kinetics and decomposition characteristics of pine trees. Bioresour Technol. 2010;101(24):9797–802.CrossRefPubMedGoogle Scholar
  31. 31.
    Wang G, et al. TG study on pyrolysis of biomass and its three components under syngas. Fuel. 2008;87(4):552–8.CrossRefGoogle Scholar
  32. 32.
    Mui ELK, et al. Kinetic study on bamboo pyrolysis. Ind Eng Chem Res. 2008;47(15):5710–22.CrossRefGoogle Scholar
  33. 33.
    Kashiwagi T, Inaba A, Brown JE. Differences in PMMA degradation characteristics and their effects on its fire properties. Fire Saf Sci. 1986;1:483–93.CrossRefGoogle Scholar
  34. 34.
    Kissinger HE. Variation of peak temperature with heating rate in differential thermal analysis. J Res Nat Bur Stand. 1956;57(4):217–21.CrossRefGoogle Scholar
  35. 35.
    Missoum A, Gupta AK, Chen J. Global kinetics of the thermal decomposition of waste materials. In: Thirty-second intersociety energy conversion engineering conference (IECEC-97). Honolulu, HI; 1997. p. 636–41.Google Scholar
  36. 36.
    Quan C, Li A, Gao N. Thermogravimetric analysis and kinetic study on large particles of printed circuit board wastes. Waste Manag. 2009;29(8):2353–60.CrossRefPubMedGoogle Scholar
  37. 37.
    Milosavljevic I, Oja V, Suuberg EM. Thermal effects in cellulose pyrolysis: relationship to char formation processes. Ind Eng Chem Res. 1996;35(3):653–62.CrossRefGoogle Scholar
  38. 38.
    Lautenberger C, Rein G, Fernandez-Pello C. The application of a genetic algorithm to estimate material properties for fire modeling from bench-scale fire test data. Fire Saf J. 2006;41(3):204–14.CrossRefGoogle Scholar
  39. 39.
    Opfermann J. Kinetic analysis using multivariate non-linear regression. I. Basic concepts. J Therm Anal Calorim. 2000;60(2):641–58.CrossRefGoogle Scholar
  40. 40.
    Ballistreri A, Montaudo G, Puglisi C. Reliability of the volatilization method for determination of the activation energy in the thermal decomposition of polymers. J Therm Anal. 1984;29(2):237–41.CrossRefGoogle Scholar
  41. 41.
    Zhang H. Fire-safe polymers and polymer composites. Washington: Federal Aviation Administration, Office of Aviation Research; 2003.Google Scholar
  42. 42.
    Han TU, et al. Pyrolysis kinetic analysis of poly(methyl methacrylate) using evolved gas analysis-mass spectrometry. Korean J Chem Eng. 2017;34(4):1214–21.CrossRefGoogle Scholar
  43. 43.
    Ang HG, Pisharath S. Energetic polymers. New York: Wiley; 2012.Google Scholar
  44. 44.
    Haseli Y, van Oijen JA, de Goey LPH. Modeling biomass particle pyrolysis with temperature-dependent heat of reactions. J Anal Appl Pyrol. 2011;90(2):140–54.CrossRefGoogle Scholar
  45. 45.
    Peterson JD, Vyazovkin S, Wight CA. Kinetic study of stabilizing effect of oxygen on thermal degradation of poly(methyl methacrylate). J Phys Chem B. 1999;103(38):8087–92.CrossRefGoogle Scholar
  46. 46.
    Frederick WJ, Mentzer CC. Determination of heats of volatilization for polymers by differential scanning calorimetry. J Appl Polym Sci. 1975;19(7):1799–804.CrossRefGoogle Scholar
  47. 47.
    Harper CA. Handbook of building materials for fire protection. New York: McGraw-Hill; 2004.Google Scholar
  48. 48.
    Steinhaus T. Evaluation of the thermophysical properties of poly(methylmethacrylate): a reference material for the development of a flammability test for micro-gravity environments. College Park: Department of Fire Protection Engineering, The University of Maryland; 1999.Google Scholar
  49. 49.
    Zeng WR, Li SF, Chow WK. Preliminary studies on burning behavior of polymethylmethacrylate (PMMA). J Fire Sci. 2002;20(4):297–317.CrossRefGoogle Scholar
  50. 50.
    Spearpoint MJ, Quintiere JG. Predicting the piloted ignition of wood in the cone calorimeter using an integral model: effect of species, grain orientation and heat flux. Fire Saf J. 2001;36(4):391–415.CrossRefGoogle Scholar
  51. 51.
    Linteris GT et al. Modeling solid sample burning. In: Eighth international symposium international association for fire safety science (IAFSS). Boston, MA; 2005.Google Scholar
  52. 52.
    Nelson GL, Jayakody C. Flame retardant polyurethane. In: Flame retardant polymerics: electrical/electronic applications. Boca Raton: CRC Press; 1998. p. 1–28.Google Scholar
  53. 53.
    Babrauskas V, Peacock RD. Heat release rate: the single most important variable in fire hazard. Fire Saf J. 1992;18(3):255–72.CrossRefGoogle Scholar
  54. 54.
    Mulholland GW, Croarkin C. Specific extinction coefficient of flame generated smoke. Fire Mater. 2000;24(5):227–30.CrossRefGoogle Scholar
  55. 55.
    Assael MJ, et al. Thermal conductivity of polymethyl methacrylate (PMMA) and borosilicate crown glass BK7. Int J Thermophys. 2005;26(5):1595–605.CrossRefGoogle Scholar
  56. 56.
    Jansson R. Measurement of thermal properties at elevated temperatures: Brandforsk project 328-031. SP report 2004:46, 2004.Google Scholar
  57. 57.
    Smith WF, Hashemi J. Polymeric materials. In: Foundations of materials science and engineering. New York: McGraw-Hill; 2006. p. 515–6.Google Scholar

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2018

Authors and Affiliations

  1. 1.School of Housing, Building and PlanningUniversiti Sains MalaysiaGeorge TownMalaysia
  2. 2.Centre for Environmental Safety and Risk EngineeringVictoria UniversityMelbourneAustralia
  3. 3.Institute for Sustainable Industries and Liveable CitiesVictoria UniversityMelbourneAustralia

Personalised recommendations