Optimization of saponification process in multi-response framework by using desirability function approach

Abstract

In chemical engineering field, there are many processes which need to optimize more than one responses, called multiresponse, simultaneously. In this study, it is aimed to analyse the effects of operating parameters (modeling) and to obtain the compromise process factor values (optimization) for a continuous saponification process. The novelty of this study is considering the saponification process as a multi-response problem. It is important both engineering and statistical aspects. For the continuous saponification process, sodium hydroxide (X1), ethyl acetate concentrations (X2), and their volumetric flow rates (X3, X4) were regarded as the process factors in order to maximize the conversion of sodium hydroxide (Y1) and to minimize the space time (Y2) which is calculated analytically by using X3 and X4. Response Surface Methodology (RSM) and Desirability Function Approach (DFA) were used for modeling and optimization of the process, respectively. Therefore, it is clear that compromise factor conditions which are obtained by the optimization of conversion and space time simultaneously will satisfy the product quality and process economy.

Keywords

• Saponification process
• Response Surface Methodology (RSM)
• desirability function
• optimization

İstenebilirlik Fonksiyonu Yaklaşımı Kullanılarak Çok Yanıtlı Çerçevede Sabunlaşma Sürecinin Optimizasyonu

Abstract

Kimya mühendisliği alanında, çok yanıtlı problem olarak adlandırılan, birden fazla yanıtın eşanlı optimizasyonunu gerektiren pek çok süreç mevcuttur. Bu çalışmada, bir sürekli sabunlaşma süreci için süreç parametrelerinin etkilerinin analizi (modelleme) ve uzlaşık süreç parametre değerlerinin elde edilmesi (optimizasyon) amaçlanmıştır. Bu çalışmanın özgünlüğü, sabunlaşma sürecinin çok yanıtlı bir problem olarak ele alınmasıdır. Bu, mühendislik ve istatistiksel yönden önemlidir. Sürekli sabunlaşma süreci için, sodyum hidroksit (X1), etil asetat derişimleri (X2) ve onların hacimsel akış hızları (X3, X4), sodyum hidroksit dönüşümünü (Y1) maksimum ve işletme süresini (Y2) minimum yapmak amacıyla süreç faktörleri olarak ele alınmıştır. Burada, Y2 değişkeni, X3 ve X4 değişkenlerini kullanarak analitik olarak hesaplanmıştır. Yanıt Yüzey Yöntemi (YYY) ve İstenebilirlik Fonksiyonu Yaklaşımı (İFY), sırasıyla sürecin modellenmesi ve optimizasyonu için kullanılmıştır. Böylece, dönüşüm ve işletme süresi yanıtlarının eşanlı optimizasyonu ile elde edilen uzlaşık faktör koşullarının, üretim kalitesini ve süreç ekonomisini sağlayacağı açıktır.

Keywords

• Sabunlaşma süreci
• Yanıt Yüzey Yöntemi (YYY)
• istenebilirlik fonksiyonu
• optimizasyon

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