Thermodynamic study for hydrogen production from bio-oil via sorption-enhanced steam reforming: Comparison with conventional steam reforming

Abstract

The thermodynamic analysis of the sorption-enhanced steam reforming (SESR) process of bio-oil for hydrogen production was investigated in terms of equilibrium compositions, energy consumption, with the comparison with the conventional steam reforming (CSR) process. Compared to CSR process, the SESR process could obtain higher H2 yield and concentration at lower temperature and S/C ratio, with both of the yield and concentration reaching over 90%. For decreasing the energy consumption, the sensible heat of the hot output streams from the two processes was recovered, with the recovered heat calculated by pinch analysis. To produce the same amount H2, the total energy demand of the SESR process was obviously lower the CSR process, especially under low temperature zone. Finally, the parameters of the two processes were optimized with a matrix analysis method. For SESR process, the optimal SR conditions were the temperature of 500 °C–600 °C, the S/C ratio of 3.0, under which the consumptions of bio-oil and energy were about 20% and about 30% lower than those under the optimal conditions of CSR process, respectively.