Oxidation of copper at high temperature as an example for gas-solid reactions in a downer reactor – experiments and model-based analysis

One-Dimensional Heterogeneous Reaction Model of a Drop-Tube Carbonator Reactor for Thermochemical Energy Storage Applications

“…The carbonator reactor resembles a drop-tube (Figure 2) and is suitable for a wide range of fast gas-solid reaction systems [18,[20][21][22]. It is divided into two sections and the dimensions selected (~0.154 m diameter and ~4 m length) are appropriate to achieve a long solid phase residence time.…”

“…The two reactor segments are surrounded by electric furnaces that preheat the carbonator system in order to trigger the carbonation reaction (~400-500 °C). The carbonator reactor resembles a drop-tube (Figure 2) and is suitable for a wide range of fast gas-solid reaction systems [18,[20][21][22]. It is divided into two sections and the dimensions selected (~0.154 m diameter and~4 m length) are appropriate to achieve a long solid phase residence time.…”

“…In recent years, there have been numerous published works that have examined the simulation of heterogeneous gas-solid reaction systems in drop-tube or downflow reactors using mathematical models with different levels of complexity and accuracy [16][17][18][19][20][21][22][23][24]. Drop-tube reactors present a number of advantages compared to other types of reactors (i.e., risers), and are well known in the chemical and petrochemical industries.…”

“…Moreover, Kasule et al [18] developed a detailed mathematical model for the gasification of biomass in a single-stage, downward-firing, entrained-flow gasifier whereas the dynamic terms are involved later in [28]. Other similar studies have focused on the modelling strategies of different kinds of heterogeneous gas-solid reaction systems such as the oxidation of copper particles at high temperatures in a downer reactor [22], or the carbonation of CaO for CO 2 capture applications in cement kilns [20]. Finally, two recent studies have presented the construction of novel experimental facilities for the carbonation of fine CaO particles in a drop-tube reactor [29] and an entrained-flow reactor [30], examining the efficiency of the decarbonization of gases when exposed to different conditions and materials.…”

“…The entrained-flow system is assumed to be very dilute in the solid phase, such that the particle-wall and interparticle interactions may be neglected. Consequently, the conductive heat transfer mechanism between single particles and particles to the wall is neglected [22].…”