Morten Ronnekleiv

Process design simulation of H2 production by sorption enhanced steam methane reforming: evaluation of potential CO2 acceptors

A concept for pure H2 production with CO2 capture by sorption enhanced steam methane reforming (SESMR) has been investigated. Conventional steam reforming with CO2 capture has been used as a base case for comparison. SESMR resulted in competitive thermal efficiencies, which were highly dependent on the CO2 acceptor material. Thus, CaO and other more novel solid acceptors such as Li2ZrO3, K-doped Li2ZrO3, Na2ZrO3 and Li4SiO4 were screened in terms of thermodynamics, kinetics and stability. It was concluded that higher H2 yields and efficiencies can be obtained for the acceptors that have good ability for removing CO2 at low partial pressures. The best efficiencies were obtained using CaO as acceptor due to its more favourable thermodynamics and high reaction rates; however, the stability of CaO has to be improved. On the other hand, Na2ZrO3 is a promising alternative due to the good kinetics for CO2 removal and the stability.

Estimation of a deactivation model for the methanol synthesis catalyst from historic process data

Publisher Summary This chapter discusses the estimation of a deactivation model for the methanol synthesis catalyst that includes the effect of temperature and water, based on historic process data from a methanol plant. A model on the generalized power-law form was successfully fitted to process data from a limited period of time. The estimated model is of second order. No measurable effect of water was found, probably, because the variations in the feed compositions were too small. The model parameters are not valid for the total catalyst lifetime, because the deactivation process is fast in the beginning and slower after some time. Data from a larger period of time is needed to estimate a model that is valid over the total catalyst lifetime. The historic process data contains enough information to estimate a catalyst deactivation model that describes the effect of temperature but too little information to estimate the effect of the reaction-mixture composition.