Supersaturation Control using Analytical Crystal Size Distribution Estimator for Temperature Dependent in Nucleation and Crystal Growth Phenomena

Malaysian Technical Universities Conference on Engineering and Technology 2017

Zahari, Zakirah Mohd^1 ; Adnan, Siti Zubaidah^1 ; Kanthasamy, Ramesh^1 ; Saleh, Suriyati^1 ; Abdul Samad, Noor Asma Fazli^1

Faculty of Chemical and Natural Resources Engineering, Universiti Malaysia Pahang, Lebuhraya Tun Razak, Pahang, Kuantan

26300, Malaysia^1

关键词: Arrhenius expressions;    Crystal size distributions;    Effects of temperature;    Potassium sulphate;    Secondary nucleation;    Supersaturation controls;    Temperature dependence;    Temperature dependent;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/318/1/012013/pdf
DOI  :  10.1088/1757-899X/318/1/012013

来源: IOP

【 摘 要 】

The specification of the crystal product is usually given in terms of crystal size distribution (CSD). To this end, optimal cooling strategy is necessary to achieve the CSD. The direct design control involving analytical CSD estimator is one of the approaches that can be used to generate the set-point. However, the effects of temperature on the crystal growth rate are neglected in the estimator. Thus, the temperature dependence on the crystal growth rate needs to be considered in order to provide an accurate set-point. The objective of this work is to extend the analytical CSD estimator where Arrhenius expression is employed to cover the effects of temperature on the growth rate. The application of this work is demonstrated through a potassium sulphate crystallisation process. Based on specified target CSD, the extended estimator is capable of generating the required set-point where a proposed controller successfully maintained the operation at the set-point to achieve the target CSD. Comparison with other cooling strategies shows a reduction up to 18.2% of the total number of undesirable crystals generated from secondary nucleation using linear cooling strategy is achieved.