The pyrolysis behavior of three typical agricultural residues including rice husk, rice straw and wheat straw, was studied at different heating rates(15℃/min, 40℃/min and 100℃/min) in a dynamic nitrogen flow ...The pyrolysis behavior of three typical agricultural residues including rice husk, rice straw and wheat straw, was studied at different heating rates(15℃/min, 40℃/min and 100℃/min) in a dynamic nitrogen flow of 80mL/min by TG analysis coupled with Fourier Transform Infrared Spectroscopy (FT-IR). The various gaseous products released during biomass pyrolysis were examined. The kinetic parameters under different heating rates were acquired by kinetics analysis. The correlation coefficients are above 0.99. The results show that as heating rate increases the TG curve shifts to low temperature zone and the peak of DTG curve goes to low temperature area accordingly, but the total weight loss and activation energy of pyrolysis fluctuate little. The releasing behavior of gaseous products during pyrolysis of the three samples is similar. CO, CO2, H2O, CH4 and organics are the main gaseous products during biomass pyrolysis. When the heating rate increases, the yield of gaseous products released increases, so does the releasing rate.展开更多
Using Fourier Transform Infrared (FTIR) combined with an adiabatic oxidation test, temperature-programmed oxidation and gas analysis, we studied the changes of active functional groups during low-temperature oxidation...Using Fourier Transform Infrared (FTIR) combined with an adiabatic oxidation test, temperature-programmed oxidation and gas analysis, we studied the changes of active functional groups during low-temperature oxidation of lignite, gas coal, fat coal and anthracite. During slow low-temperature heat accumulation, aliphatic hydrocarbons, such as methyl and methylene, are attacked by oxygen atoms absorbed by pores on coal surfaces, generating unstable solid intermediate carbon-oxygen complexes, which then decompose into gaseous products (CO, CO2) and stable solid complexes. At the accelerated oxidation stage, the stable complexes begin to decompose in large amounts and provided new active sites for further oxidation, while the aliphatic structures gained energy and fell from the benzene rings to produce CxHy and H2.展开更多
文摘The pyrolysis behavior of three typical agricultural residues including rice husk, rice straw and wheat straw, was studied at different heating rates(15℃/min, 40℃/min and 100℃/min) in a dynamic nitrogen flow of 80mL/min by TG analysis coupled with Fourier Transform Infrared Spectroscopy (FT-IR). The various gaseous products released during biomass pyrolysis were examined. The kinetic parameters under different heating rates were acquired by kinetics analysis. The correlation coefficients are above 0.99. The results show that as heating rate increases the TG curve shifts to low temperature zone and the peak of DTG curve goes to low temperature area accordingly, but the total weight loss and activation energy of pyrolysis fluctuate little. The releasing behavior of gaseous products during pyrolysis of the three samples is similar. CO, CO2, H2O, CH4 and organics are the main gaseous products during biomass pyrolysis. When the heating rate increases, the yield of gaseous products released increases, so does the releasing rate.
基金Financial support for this work provided by the National Natural Science Foundation of China (No.50674088) is deeply appreciated
文摘Using Fourier Transform Infrared (FTIR) combined with an adiabatic oxidation test, temperature-programmed oxidation and gas analysis, we studied the changes of active functional groups during low-temperature oxidation of lignite, gas coal, fat coal and anthracite. During slow low-temperature heat accumulation, aliphatic hydrocarbons, such as methyl and methylene, are attacked by oxygen atoms absorbed by pores on coal surfaces, generating unstable solid intermediate carbon-oxygen complexes, which then decompose into gaseous products (CO, CO2) and stable solid complexes. At the accelerated oxidation stage, the stable complexes begin to decompose in large amounts and provided new active sites for further oxidation, while the aliphatic structures gained energy and fell from the benzene rings to produce CxHy and H2.
