Cost Minimization Of Recycling Processes At Eti Aluminum Plants

Abstract: This paper presents a minimization model to reduce cost of recycling process of caustic in red mud in hydrate serving product facility, a unit of ETI Alumina Plants. Caustic is very important for ETI Alumina Plants, because it is so expensive that an optimization procedure is necessary for the cost minimization. At the same plants there is also a hydrate serving product facility. One should, therefore, determine the global cheapest mixing and recycling cost. A generic non-linear program formulation for a recycling process is available in the literature, which is employed in this study. This program helps to minimize the cost of caustic recycling process. Key words: Cost minimization, recycling, chemical processes, optimization Özet: Bu makale belli bir Eti Alüminyum Fabrikasındaki kostiğin yeniden kazanımının maliyetini azaltmak için bir minimizasyon modeli sunar. Kostik, Eti Alüminyum Fabrikaları için çok önemlidir. Çünkü, geri dönüşüm maliyeti çok yüksektir ve bu maliyeti düşürmek için bir optimizasyon gereklidir. Bu yüzden, en ucuz karışım ve geri dönüşüm maliyeti belirlenmelidir. Literatürde, geri dönüşüm prosesi için bir generic non-lineer program formülasyonu mevcuttur; bu çalışmada bu non-lineer programlama probleminin formülasyonu kullanılmıştır. Bu programlama, kostiğin geri dönüşüm maliyetini minimize eder. Anahtar Kelimeler: Maliyet minimizasyonu, geri dönüşüm, kimyasal süreçler, optimizasyo

A Numerical Comparison for a Discrete HIV Infection of CD4+ T-Cell Model Derived from Nonstandard Numerical Scheme

A nonstandard numerical scheme has been constructed and analyzed for a mathematical model that describes HIV infection of CD4+ T cells. This new discrete system has the same stability properties as the continuous model and, particularly, it preserves the same local asymptotic stability properties. Linearized Stability Theory and Schur-Cohn criteria are used for local asymptotic stability of this discrete time model. This proposed nonstandard numerical scheme is compared with the classical explicit Euler and fourth order Runge-Kutta methods. To show the efficiency of this numerical scheme, the simulated results are given in tables and figures