Feedback control method of granularity for crystal product in intermittent cooling and crystallization process

Abstract

The invention relates to a feedback control method of the granularity for a crystal product in an intermittent cooling and crystallization process. According to the technical scheme, the feedback control method comprises the following specific realization steps: estimating the total quantity Ns of crystal particles according to an expected needed crystal product average grain diameter; comparing the total quantity N of crystal particles in crystallization mother liquid, which is determined through an online granularity detector in real time, with the total quantity Ns of the crystal particles specified by production; synchronously controlling heating and cooling speeds in a crystal crushing system II and a crystallizer until crystal products with expected granularity distribution are produced. Compared with a traditional granularity control method of the intermittent cooling and crystallization process, only one specified parameter, namely the total quantity Ns of the crystal particles, needs to be adjusted, a novel process parameter and a grinding and sieving process do not need to be optimized through a lot of experiment operation, and the crystal products with the expected specified granularity distribution can be automatically and conveniently produced according to requirements; a granularity controllable adjustment function of the crystal products produced according to the requirements and having the specified granularity distribution is realized.

Description

technical field [0001] The invention belongs to the technical field of industrial crystallization, and in particular relates to a method for feedback control of the particle size of crystal products in an intermittent cooling crystallization process. Background technique [0002] The batch crystallization process is widely used in the fine chemical and pharmaceutical industries that require increasingly higher purity, particle size and crystal form of product crystals. Generally speaking, product crystals with large average particle size and monodisperse distribution are expected by the process industry, which can not only effectively improve the efficiency of downstream unit operations (such as centrifugation and drying processes after crystallization), but also improve the product process yield. It can also improve the efficacy of the product (such as bioavailability, drug stability). At present, the industrial crystallization process of many fine chemicals such as pharma...

AI Technical Summary

Problems solved by technology

[0005] The present invention aims to overcome the technical defect of non-uniform particle size distribution of crystal products in the existing intermittent cooling and crystallization process. The particle size distribution is concentrated, and the crystallization operation can be automatically regulated according to the specified average particle size of the crystal product to realize the controllable production of the average particle size of the crystal product

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