SMBR.Simulated moving bed reactor

The simulated moving bed reactor (SMBR) based on the simulated moving bed (SMB) process is a practical alternative for implementing counter-current continuous reactors. Counter-current movement of the phases is simulated by sequentially switching the inlet and outlet ports located between the columns in direction of the liquid flow (Fig. 8.4). As with the SMB process, two different concepts are known to realize the counter-current flow. One is based on switching the ports and the other on the movement of columns. However, both require elaborate process control concepts to realize the movement. Owing to the periodical changes of the set-up the pro-... 

Lode, F. (2002) A simulated moving bed reactor (SMBR) for esterifications. Dissertation. ETH Zurich. 

A novel reactive separation method consists of using simulated moving bed reactor (SMBR), a type of continuous chromatographic reactor. Pereira et al. reported an experimentally ethyl lactate productivity of 3.36 kggL/L,gsjjj day (mass of ethyl lactate produced per unit volume of catalyst employed and unit time) and ethyl lactate purity of 75%. 

Two different modeling approaches are used for simulated moving bed reactors. The first approach combines the model of several batch columns with the mass balances for the external inlet and outlet streams. By periodically changing the boundary conditions the transient behavior of the process is taken into account. The model is based on the SMB model introduced in Chapter 6 and is, therefore, referred to as the SMBR model. The second approach assumes a true counter-current flow of the solid and the liquid phase like the TMBR. Therefore, this approach is called the TMBR model. 

In order to reduce the high ethanol consumption, Silva et al. applied the simulated moving bed membrane reactor (PermSMBR) for the production of ethyl lactate. In PermSMBR, each column contains the catalyst and a set of hydrophilic membranes to increase the water removal, leading to a better process performance. A theoretical model was developed to evaluate the PermSMBR process performance for different conditions. Authors concluded that ethanol consumption with SMBR is 152% higher than the one with PermSMBR, and 165% higher than the one with reactive distillation for a similar ethyl lactate production. 

---