The performance of a solid-liquid separation process is often limited by size distribution and morphology of the crystals. To predict the filtration behavior, a robust and applicable model based only on crystallization process parameters is necessary. Therefore, a model has been successfully developed for the industrial system of aqueous acrylic acid melt to predict compressibility and permeability of a crystal bed. For this purpose, common equations are transferred successfully to nonspherical particles. Chord length distributions (CLDs) obtained from an inline focused beam reflectance measurement (FBRM) probe and crystal aspect ratios have been used in combination to determine the major input parameters for the model. Integration of a complex mathematical restoration of crystal size distribution (CSD) from CLD data by the use of existing models is avoided. Considering acceptable fault tolerances of the model, a simple approach used as a robust industrial application is employed. The adjustment of all required constants used in the permeability model was based on simple filtration tests. IntroductionSuspension crystallization is a highly efficient separation technology for industrial applications. In the recent past, several developments have been made to push this promising technology successfully to industrial scale. The overall efficiency of the process is largely determined by an effective solid-liquid separation. To obtain high product purities, complete separation of the crystals and mother liquor is required along with an efficient washing step.Hengstermann et al. [1] showed that the amount of the water content in the melt and the driving force in terms of the supercooling are the main influencing factors in the crystallization of acrylic acid. With increase in the water content and supercooling, a cavity starts appearing at the crystal extremity, of face {002}, and goes along with a needle-like shape development. This morphology trend is often an indicator of problems coming up in downstream facilities like solid-liquid separation and washing devices. Simple tests at lab-scale confirm these issues and show challenging filtration conditions at higher water contents and supercooling.Therefore, the scope of the present work is to investigate the influence of water content and supercooling in the melt on the performance of the downstream solid-liquid separation. The filterability performance of different crystal suspensions was determined by simple filtration tests. In these tests, different compressive stresses were applied on the crystal bed by means of different liquid pressure drops. Later on, the experimental results were used as input parameters for an extended model which was developed previously to calculate permeability and compressibility. State of KnowledgeThe main scope of the required model is to describe the permeability performance of a crystal bed formed from nonspherical acrylic acid crystals under the influence of mechanical stress. Hengstermann et al. [1] identified the water content and ...