Optimization of a Six-Zone Simulated-Moving-Bed Chromatographic Process

Abstract

Using strong cation exchange simulated moving bed (SMB) chromatography, a nitrogen-phosphate-potassium (NPK) fertilizer is produced in a cost-effective manner. The SMB process operated in a non-traditional way is divided into production and regeneration sections for exclusion of undesirable ions, and composed of six zones including two wash-water zones. This paper addresses modeling, simulation and optimization studies on this ionexchange SMB process, based upon experimental data obtained both from a pilot plant and an industrial plant. This study aims to optimize the SMB process in terms of i) maximization of productivity in the production section and ii) minimization of wash-water consumption, thereby resulting in i) increasing the profit and ii) reducing the overall operating cost in the downstream processing, respectively. The two objectives are sequentially treated within the framework of a multi-level optimization procedure (MLOP) which includes two pre-optimization levels, a productivity maximization level and a desorbent (or wash-water) consumption minimization level. In this optimization study, it is demonstrated that wash-water consumption can be reduced by 5 % at a 5% higher productivity.

State-of-arts in Multiscale Simulation for Process Development

“…[35,37]. (liquid-film mass transfer coefficient, k f )과 입자 내 확산계수(intraparticle diffusivity)으로 구할 수 있다 [65]. 또한, 입자 내 확산계수는 기공확산계수(macrospore diffusivity, D pore )와 흡착제 고체상 확산계 수(solid diffusivity, D solid )로 구분할 수 있다 [66,67].…”

Effect of dead volume on performance of simulated moving bed process

“…SMB chromatography usually works with the inherent advantage of a high driving force due to counter-current flow, resulting in low solvent consumption, small apparatus scale and high yield, compared to batch chromatography (Lim and Jorgensen 2007;Zhang et al 2004a). In SMB operation, the countercurrent movement of fluid and solid is simulated by an appropriate flow switching sequence, resolving problems associated with the solid circulation in the true moving bed (TMB) unit where liquid and solid flow in the opposite direction.…”

“…A simple way for the consideration of dead volume was to use an effective bed length and effective bed voidage (Beste et al 2000;Lim and Jorgensen 2007). The effect of extra-column dead volume on SMB performance was theoretically analyzed in the framework of both the triangle theory (Migliorini et al 1999) and standing wave design (Mun et al 2003) in terms of the time delay caused by the dead volume.…”

Preparative-scale separation by simulated moving bed chromatography of biocatalytically produced regioisomeric lactones

“…Major large-scale applications at multi-ton scale can be found in the petrochemical [4], corn [5], agrochemical [6] and sugar [7][8] industries. While SMB started in petrochemical and sugar production, it has attracted increased attention in the pharmaceutical industry [9][10][11][12] as a powerful separation technology and the majority of preparative SMB units are installed in the chemical, pharmaceutical and food industries [13].…”