Online control method for particle size distribution in solventing-out crystallization process

Abstract

The invention discloses an online control method for particle size distribution in solventing-out crystallization process. The method comprises the steps that an ATR probe is used for measuring the concentration of a current solute on an anti-solvent crystallization online detection control device, an FBRM probe is used for measuring the particle size distribution of the current solute, and a constant-temperature water bath is used for controlling the temperature in a current crystallization kettle; the solute concentration obtained by current measurement is taken as a state variable, the current test temperature is taken as an operation variable, the state variable and the current test temperature are input into a process model, the process model is solved to obtain the particle size distribution of a crystallization end point, and minimization of an objective function TARGET = | n (L, tf)-n (L, t) s | | 2 is taken as an optimization target, and an optimization equation in combinationwith the search range of the operation variable is obtained; the temperature of the crystallization kettle is adjusted according to the optimal cooling curve, so that the temperature in the crystallization kettle is matched with the optimal cooling curve; a target value is set, and whether a crystallization end point is reached is judged through the target value. According to the method, negligible coalescence and fragmentation in the actual process are considered, and the problem of numerical discretization in the solving process of coalescence and fragmentation items is solved.

Description

technical field [0001] The invention relates to the technical field of crystallization process control, in particular to a method for on-line control of the dissolution and crystallization process based on computer simulation real-time measurement Background technique [0002] Crystallization is widely used in food, medicine and other fine chemical fields due to its advantages of high efficiency, high crystal purity, and low pollution. Dissolution crystallization is a commonly used and effective method for purification and separation of substances, with low operating temperature and simple equipment. , Low energy consumption, especially suitable for heat-sensitive substances. The manufacturing process and product requirements of the downstream process put forward higher requirements on the quality of crystal products such as particle size distribution and crystal habit. It is of great significance to improve the quality of crystal products by modeling and controlling the pa...

AI Technical Summary

Problems solved by technology

The traditional control curve is generally linear or explored through the process, the control effect is poor, and the product quality is low

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