Isothermal combustion characteristics of anthracite and spent coffee grounds briquettes

  • Yuanhang Wei
  • Meiqian ChenEmail author
  • Qinghai LiEmail author
  • Shibo Niu
  • Yang Li


The isothermal combustion characteristics of anthracite and spent coffee grounds briquettes in a bench-scale fixed-bed furnace were examined by using a macro-thermogravimetric analysis approach between 873 and 1173 K. The combustion performances in terms of the conversion rates, flame evolution, pollutant emissions, ash compositions and ash fusion temperatures of two anthracite/spent coffee grounds blend briquettes with blending ratios of 40% and 60% were also compared with those of their individuals. There was only an obvious peak in DTG profile for every sample at each temperature. At 973 K, the average burning rate of the spent coffee grounds was about 8 times higher than that of the anthracite. The average burning rate of 60% anthracite/40% spent coffee grounds blend at 1173 K increased by about 3 times in comparison with that at 873 K. NO2 emissions for the four samples were much less than other gaseous emissions. The four ash fusion temperatures for the anthracite were higher than 1791 K. The deformation temperature, softening temperature, hemispherical temperature and flow temperature for the spent coffee grounds were 1526, 1626, 1687 and 1791 K. The ash fusion characteristics of the spent coffee grounds were improved by blending the anthracite.


Isothermal combustion Spent coffee grounds Anthracite Macro-thermogravimetric analysis Emissions Fixed bed 

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


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2018

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
  3. 3.Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power EngineeringTsinghua UniversityBeijingChina

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