Evaluation on the non-isothermal combustion kinetics of lignite and sewage sludge through microwave pretreatment

  • Y. Li
  • M. Q. ChenEmail author
  • Y. W. Huang


Lignite and sewage sludge powder were pretreated through microwave heating at a power level of 119 W. The non-isothermal combustion characteristics of lignite and sewage sludge powder through the microwave pretreatment were examined based on a thermo-gravimetric technique at three heating rates (10, 20 and 30 °C min−1). The effect of the microwave pretreatment on the combustion performance index and kinetic parameters was addressed. The ignition temperature region of the lignite samples was in between 357 and 376 °C, which was higher than that of the sewage sludge samples ranged from 219 to 235 °C. The comprehensive performance index of the treated lignite and sewage sludge increased by 22.5% and 2.3%, respectively. The combustion kinetic parameters of the samples were evaluated based on KAS method coupled with Criado method. The average activation energies of the untreated lignite and sewage sludge were 213.83 and 176.92 kJ mol−1, while that for the treated samples were 232.64 and 203.01 kJ mol−1.


Lignite Sewage sludge Microwave pretreatment Combustion performance Kinetics 

List of symbols


Pre-exponential factor (s−1)


Apparent activation energy (kJ mol−1)


Microwave pretreatment


The universal gas constant (kJ mol−1K−1)


Temperature (K)

Greek letters


Conversion degree


Heating rate







Comprehensive performance



This work was supported by the National Natural Science Foundation of China under No. 51376017.

Supplementary material

10973_2019_9107_MOESM1_ESM.docx (193 kb)
Supplementary material 1 (DOCX 193 kb)


  1. 1.
    Rao Z, Zhao Y, Huang C, Duan C, He J. Recent developments in drying and dewatering for low rank coals. Prog Energy Combust Sci. 2015;46(33):1–11. Scholar
  2. 2.
    Zhang Y, Zheng Y, Yang M, Song Y. Effect of fuel origin on synergy during co-gasification of biomass and coal in CO2. Biores Technol. 2016;200(33):789–94. Scholar
  3. 3.
    Ge L, Zhang Y, Xu C, Wang Z, Zhou J, Cen K. Influence of the hydrothermal dewatering on the combustion characteristics of Chinese low-rank coals. Appl Therm Eng. 2015;90(33):174–81. Scholar
  4. 4.
    Sun B, Yu J, Tahmasebi A, Han Y. An experimental study on binderless briquetting of Chinese lignite: effects of briquetting conditions. Fuel Process Technol. 2014;124(33):243–8. Scholar
  5. 5.
    Song Y, Feng W, Li N, Li Y, Zhi K, Teng Y, et al. Effects of demineralization on the structure and combustion properties of Shengli lignite. Fuel. 2016;183(33):659–67. Scholar
  6. 6.
    Roy B, Bhattacharya S. Ash characteristics during oxy-fuel fluidized bed combustion of a Victorian brown coal. Powder Technol. 2016;288:1–5. Scholar
  7. 7.
    Liu P, Le J, Zhang D, Wang S, Pan T. Free radical reaction mechanism on improving tar yield and quality derived from lignite after hydrothermal treatment. Fuel. 2017;207:244–52. Scholar
  8. 8.
    Jiang L, Yuan X, Xiao Z, Liang J, Li H, Cao L, et al. A comparative study of biomass pellet and biomass-sludge mixed pellet: energy input and pellet properties. Energy Convers Manag. 2016;126:509–15. Scholar
  9. 9.
    Niu S, Chen M, Li Y, Xue F. Evaluation on the oxy-fuel combustion behavior of dried sewage sludge. Fuel. 2016;178:129–38. Scholar
  10. 10.
    Osman H, Jangam SV, Lease JD, Mujumdar AS. Drying of low-rank coal (LRC)—a review of recent patents and innovations. Dry Technol. 2011;29(15):1763–83. Scholar
  11. 11.
    Areeprasert C, Scala F, Coppola A, Urciuolo M, Chirone R, Chanyavanich P, et al. Fluidized bed co-combustion of hydrothermally treated paper sludge with two coals of different rank. Fuel Process Technol. 2016;144:230–8. Scholar
  12. 12.
    Sakaguchi M, Laursen K, Nakagawa H, Miura K. Hydrothermal upgrading of Loy Yang Brown coal: effect of upgrading conditions on the characteristics of the products. Fuel Process Technol. 2008;89(4):391–6. Scholar
  13. 13.
    Magdziarz A, Werle S. Analysis of the combustion and pyrolysis of dried sewage sludge by TGA and MS. Waste Manag. 2014;34(1):174–9. Scholar
  14. 14.
    Liu H, Chen M, Han Z, Chen G, Lu T. Nonisothermal kinetics based on two-stage scheme for co-drying of biomass and lignite. Chem Eng Commun. 2016;203(1):18–27. Scholar
  15. 15.
    Huang YW, Chen MQ. Thin-layer isothermal drying kinetics of municipal sewage sludge based on two falling rate stages during hot-air-forced convection. J Therm Anal Calorim. 2017;129(1):567–75. Scholar
  16. 16.
    Zhang XY, Chen MQ, Huang YW, Xue F. Isothermal hot air drying behavior of municipal sewage sludge briquettes coupled with lignite additive. Fuel. 2016;171:108–15. Scholar
  17. 17.
    Yang X, Gang C, Qingyan F, Peng T, Tao Y, Cheng Z. Properties of upgraded Shengli lignite and its behavior for gasification. Energy Fuels. 2014;28:264–74.CrossRefGoogle Scholar
  18. 18.
    Kwon EE, Lee T, Ok YS, Tsang DCW, Park C, Lee J. Effects of calcium carbonate on pyrolysis of sewage sludge. Energy. 2018;153:726–31. Scholar
  19. 19.
    Karthikeyan M, Zhonghua W, Mujumdar AS. Low-rank coal drying technologies: current status and new developments. Dry Technol. 2009;27(3):403–15. Scholar
  20. 20.
    Fu BA, Chen MQ, Huang YW, Luo HF. Combined effects of additives and power levels on microwave drying performance of lignite thin layer. Dry Technol. 2017;35(2):227–39. Scholar
  21. 21.
    Cuccurullo G, Giordano L, Metallo A, Cinquanta L. Influence of mode stirrer and air renewal on controlled microwave drying of sliced zucchini. Biosyst Eng. 2017;158:95–101. Scholar
  22. 22.
    Yuan S, Liu J-Z, Zhu J-F, Zhou Q-Q, Wang Z-H, Zhou J-H, et al. Effect of microwave irradiation on the propensity for spontaneous combustion of Inner Mongolia lignite. J Loss Prev Process Ind. 2016;44(33):390–6. Scholar
  23. 23.
    Wang W, Xin F, Tu Y, Wang Z. Pore structure development in Xilingol lignite under microwave irradiation. J Energy Inst. 2016. Scholar
  24. 24.
    Cheng J, Zhou F, Wang X, Liu J, Wang Z, Zhou J, et al. Physicochemical properties of wastewater produced from the microwave upgrading process of Indonesian lignite. Fuel. 2015;158(33):435–42. Scholar
  25. 25.
    Tahmasebi A, Yu J, Han Y, Yin F, Bhattacharya S, Stokie D. Study of chemical structure changes of Chinese lignite upon drying in superheated steam, microwave, and hot air. Energy Fuels. 2012;26(6):3651–60. Scholar
  26. 26.
    Liu J-Z, Zhu J-F, Cheng J, Zhou J-H, Cen K-F. Pore structure and fractal analysis of Ximeng lignite under microwave irradiation. Fuel. 2015;146(33):41–50. Scholar
  27. 27.
    Liu X, Masuyama T, Hirajima T, Nonaka M, Sasaki K. Combustion performance of Loy Yang lignite treated using microwave irradiation treatment. Thermochim. Acta. 2016;642:81–7. CrossRefGoogle Scholar
  28. 28.
    Lester E, Kingman S. The effect of microwave pre-heating on five different coals. Fuel. 2004;83(14):1941–7. Scholar
  29. 29.
    Ge L, Zhang Y, Wang Z, Zhou J, Cen K. Effects of microwave irradiation treatment on physicochemical characteristics of Chinese low-rank coals. Energy Convers Manag. 2013;71(33):84–91. Scholar
  30. 30.
    Pang Q-H, Zhang J-L, Mao R, Jiang Z, Liu T. Mechanism of effect of microwave modification on pulverized coal combustion properties. Int J Iron Steel Res. 2014;21(3):312–20. Scholar
  31. 31.
    Yu LY, Li PS. Thermogravimetric analysis of coal and sludge co-combustion with microwave radiation dehydration. J Energy Inst. 2014;87(3):220–6. Scholar
  32. 32.
    Li Y, Chen MQ, Li QH, Huang YW. Effect of microwave pretreatment on the combustion behavior of lignite/solid waste briquettes. Energy. 2018;149:730–40. Scholar
  33. 33.
    Niu S, Chen M, Li Y, Lu T. Combustion characteristics of municipal sewage sludge with different initial moisture contents. J Therm Anal Calorim. 2017;129(2):1189–99. Scholar
  34. 34.
    Vyazovkin S, Chrissafis K, Di Lorenzo ML, Koga N, Pijolat M, Roduit B, et al. ICTAC Kinetics Committee recommendations for collecting experimental thermal analysis data for kinetic computations. Thermochim Acta. 2014;590(33):1–23. Scholar
  35. 35.
    Guo J, Chen M, Huang Y, Shokri N. Salinity effects on ultrasound-assisted hot air drying kinetics of sewage sludge. Thermochim Acta. 2019;678:178298. Scholar
  36. 36.
    Chen M, Yu D, Wei Y. Evaluation on ash fusion behavior of eucalyptus bark/lignite blends. Powder Technol. 2015;286:39–47. Scholar
  37. 37.
    Zhang XY, Chen MQ. A comparison of isothermal with nonisothermal drying kinetics of municipal sewage sludge. J Therm Anal Calorim. 2016;123(1):665–73. Scholar
  38. 38.
    Li XG, Lv Y, Ma BG, Jian SW, Tan HB. Thermogravimetric investigation on co-combustion characteristics of tobacco residue and high-ash anthracite coal. Bioresour Technol. 2011;102(20):9783–7. Scholar
  39. 39.
    Yi B, Zhang L, Mao Z, Huang F, Zheng C. Effect of the particle size on combustion characteristics of pulverized coal in an O2/CO2 atmosphere. Fuel Process Technol. 2014;128(33):17–27. Scholar
  40. 40.
    Martín-Lara MA, Blázquez G, Zamora MC, Calero M. Kinetic modelling of torrefaction of olive tree pruning. Appl Therm Eng. 2017;113:1410–8. Scholar
  41. 41.
    Criado JM, Málek J, Ortega A. Applicability of the master plots in kinetic analysis of non-isothermal data. Thermochim Acta. 1989;147(2):377–85. Scholar
  42. 42.
    Vyazovkin S, Burnham AK, Criado JM, Pérez-Maqueda LA, Popescu C, Sbirrazzuoli N. ICTAC Kinetics Committee recommendations for performing kinetic computations on thermal analysis data. Thermochim Acta. 2011;520(1):1–19. Scholar
  43. 43.
    Senum G, Yang R. Rational approximations of the integral of the Arrhenius function. J Therm Anal Calorim. 1977;11(3):445–7. Scholar
  44. 44.
    He Y, Ma X. Comparative investigation on non-isothermal kinetics for thermo-degradation of lignocellulosic substrate and its chlorinated derivative in atmospheres with CO2 participation. Bioresour Technol. 2015;189:71–80. Scholar
  45. 45.
    Ebrahimi-Kahrizsangi R, Abbasi MH. Evaluation of reliability of Coats-Redfern method for kinetic analysis of non-isothermal TGA. Trans Nonferrous Met Soc China. 2008;18(1):217–21. Scholar
  46. 46.
    Yanfen L, Xiaoqian M. Thermogravimetric analysis of the co-combustion of coal and paper mill sludge. Appl Energy. 2010;87(11):3526–32. Scholar
  47. 47.
    Ochoa A, Ibarra Á, Bilbao J, Arandes JM, Castaño P. Assessment of thermogravimetric methods for calculating coke combustion-regeneration kinetics of deactivated catalyst. Chem Eng Sci. 2017;171(33):459–70. Scholar
  48. 48.
    Liu X, Chen M, Wei Y. Combustion behavior of corncob/bituminous coal and hardwood/bituminous coal. Renew Energy. 2015;81:355–65. Scholar
  49. 49.
    Bamford CHTC. Comprehensive chemical kinetics. Amsterdam: Elsevier Scientific Publishing Company; 1980.Google Scholar

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2019

Authors and Affiliations

  1. 1.Institute of Thermal Engineering, School of Mechanical, Electronic and Control EngineeringBeijing Jiaotong UniversityBeijingChina
  2. 2.Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small ScaleBeijingChina

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