Numerical formulation of elution chromatography techniques

In order to conduct theoretical studies and analyses elution chromatography modes and configurations, there are a number of numerical techniques to solve the constitutive model equations of these processes available. These techniques approximate the analytical solution of the chromatography problem and are in the majority of cases the only available tool to obtain a solution of the model equations. The techniques differ in the level of accuracy and computational performance. Two specific numerical techniques, namely Finite Difference Approximations and Orthogonal Collocation on Finite Elements (OCFE), are analyzed for the modeling of elution chromatography for single-column batch operation. Advantages and disadvantages of each numerical technique are discussed. Simple guidelines with respect to the application of each technique are given. The more accurate technique (OCFE) is used later to analyze standard four-zone SMB configurations and single stream Fractionation and Feedback SMB1 for a specific difficult separation task