ZHANG Zhichao, LIU Jing, YANG Yingju, et al. Study on chemical kinetics of Na2SO4 formation in coal fired flue gas[J]. CIESC Journal, 2018, (8): 3643-3650. DOI: 10.11949/j.issn.0438-1157.20180051.
DOI:
ZHANG Zhichao, LIU Jing, YANG Yingju, et al. Study on chemical kinetics of Na2SO4 formation in coal fired flue gas[J]. CIESC Journal, 2018, (8): 3643-3650. DOI: 10.11949/j.issn.0438-1157.20180051.DOI:
Study on chemical kinetics of Na2SO4 formation in coal fired flue gas
The formation of gaseous sodium sulphate during Zhundong coal combustion leads to a series of problems such as the deposition and corrosion of heat exchange surface and the deactivation of tail SCR catalyst. Therefore
the kinetic study on the transformation of Na2SO4 is important for predicting and controlling the Na2SO4 formation in coal-fired flue gas. In this study
a more complicated chemical kinetic model of Na/Cl/S/O/H in flue gas was established and the formation mechanism of Na2SO4 was studied. The influence of oxygen content
temperature
SO2and H2O concentrations on Na2SO4 formation was also investigated. The model predictions were in good agreement with the experimental results. Oxygen promoted the formation of Na2SO4. Even though the chemical reactions were accelerated at high temperature
the Na2SO4 formation was inhibited. The effects of SO2 and H2O on Na2SO4 formation depended on reaction temperature. The path analysis indicated that there were two important paths to form Na2SO4:(1) the direct oxidation of SO2 (NaCl→NaSO3Cl→NaHSO4→Na2SO4)
and (2) the indirect oxidation of SO2(NaCl→NaO2→NaSO4→NaHSO4→Na2SO4). The result of sensitivity analysis showed that the Na2SO4 formation was sensitive to the reactions that generated or consumed radicals in the system.