Theoretical Study of the Scalability of a Sonicated Continuous Crystallizer for the Production of Aspirin

Abstract

Ultrasound is frequently applied in crystallization to enhance nucleation and achieve crystal sizes within a narrow range. In this work, a mathematical model is developed which couples the acoustic effect of ultrasound on the antisolvent crystallization of aspirin with the flow hydrodynamics and associated micromixing. In the first step, a qualitatively validated 3D acoustic simulation of the crystallizer is used to understand the acoustic field in the reactor. Following this an assessment of various flow and micromixing models is carried out using a 3D CFD model which is compared to a previously validated 1D model. The identified models successfully capture the acoustic field and predict the crystal size and the crystals' coefficient of variation in experimental studies. The proposed model offers a practical platform that can be applied to experiments for improving the design of continuous crystallizers, as the model has

Recent Advances in CFD Simulations of Multiphase Flow Processes with Phase Change

“…The crystallization process is crucial to the separation of solids from liquids as well as for obtaining a pure liquid. 360 It is possible to conduct the crystallization processes in batches, 14 semibatches, 361 continuous processes, 362 or fluidized beds. 67 Batch processes are widely used in industry for their low cost, especially for pharmaceuticals.…”

“…Hence, the antisolvent crystallization is usually located within the turbulent regime, which means the turbulent model is vital to accurately predict the crystal growth process and mixing phenomena for antisolvent crystalliza-tion. 360 Controlling the CSD and size of crystals is more challenging and expensive for antisolvent crystallization compared with supercooling crystallization. Oh et al 367 simulated the purification of ε-form HNIW in a pilot-scale drowning-out antisolvent crystallizer.…”

“…However, in addition to supersaturation, the efficiency and product quality of this method depends heavily on the mixing performance of the antisolvent and the solution. Hence, the antisolvent crystallization is usually located within the turbulent regime, which means the turbulent model is vital to accurately predict the crystal growth process and mixing phenomena for antisolvent crystallization . Controlling the CSD and size of crystals is more challenging and expensive for antisolvent crystallization compared with supercooling crystallization.…”

Ultrasonic Enhanced Continuous Crystallization: Induction Time and Process Control

“…A reliable crystallizer should be developed to solve the problems of energy dissipation and thermal effect. Additionally, a systematic study of the sonocrystallization process in tubular crystallizers is necessary. ,, …”

“…Additionally, a systematic study of the sonocrystallization process in tubular crystallizers is necessary. 8,27,29 In this work, a highly efficient ultrasonic tubular crystallizer was designed. Its vibration characteristics were simulated, and the sound power density was measured.…”