Population balance modeling of crystallization for monitoring and optimal control

The Population Balance Equation (PBE) describe the change in the particle size distribution occasioned by a variety of mechanisms. This study evaluate the PBE with nucleation, growth and dissolution. The nucleation with growth process is known to be problematic due to the sharp profiles that it causes. The dissolution process requires the knowledge of the number of particles at the minimal stable size, such that unstable particles are removed from the particulate phase. These conditions require the use of specialized numerical method for mathematical modeling. In this thesis, an emphasis is given in the Moving Sectional Method, which combines the method of classes with the method of characteristics to mitigate numerical diffusion errors. The work focused on the PBE application for the enantioselective crystallization of racemic compounding forming systems. Initially, the conservation of the moments of the distribution was analyzed for the MSM with growth and nucleation mechanisms and methods were proposed for the addition of new elements of the particle size mesh. The estimation of kinetic parameters was approached for the dissolution of NaCl in solutions of monoethyleneglycol (MEG) from data of color patterns (RGB), which can be obtained by experimental apparatus of low cost. A method for determining the operating conditions for the batch crystallizer based on the ternary diagram is described. Subsequently, it is shown that the information obtained in the ternary diagram, such as the maximum yield obtained by the process due to thermodynamics, can be used to formulate constraints for a control method based on non-linear optimization to obtain the desired characteristics of the product.A Equação do Balanço da População (PBE) descreve a mudança na distribuição do tamanho de partícula. Este estudo avalia a PBE com nucleação, crescimento e dissolução. Processos com nucleação e crescimento são conhecidos por serem problemáticos devido aos perfis descontínuos que causam. A dissolução requer o conhecimento do número de partículas no tamanho estável mínimo, de modo que as partículas instáveis sejam removidas da fase particulada. Essas condições requerem o uso de métodos numéricos especializados para sua modelagem matemática. Nesta tese, é dada ênfase ao Moving Section Method (MSM) que combina o método das classes com o método das características para mitigar erros de difusão numérica. O trabalho concentrou-se na aplicação do PBE para a cristalização enantiosseletiva de sistemas formadores de compostos racêmicos. Inicialmente, a conservação dos momentos da distribuição foi analisada para o MSM com mecanismos de crescimento e nucleação e propôs-se métodos para a adição de novos elementos da malha do tamanho de partículas. A estimação de parâmetros cinéticos foi abordada para a dissolução de NaCl em soluções de monoetilenoglicol (MEG) a partir de dados de padrões de cores (RGB), o que pode ser obtido por aparato experimental de baixo custo. Um método para determinar as condições de operação para o cristalizador em batelada com base no diagrama ternário é descrito. Posteriormente, mostram-se que as informações obtidas no diagrama ternário, como o rendimento máximo obtido pelo processo devido à termodinâmica, podem ser usadas para formular restrições para um método de controle baseado em otimização não linear para obter as características desejadas do produto

Modern approaches to control of a multiple hearth furnace in kaolin production

The aim of this thesis is to improve the overall efficiency of the multiple hearth furnace (MHF) in kaolin calcination by developing control strategies which incorporate machine learning based soft sensors to estimate mineralogy related constraints in the control strategy. The objective of the control strategy is to maximize the capacity of the furnace and minimize energy consumption while maintaining the product quality of the calcined kaolin. First, the description of the process of interest is given, highlighting the control strategy currently implemented at the calciner studied in this work. Next, the state of the art on control of calcination furnaces is presented and discussed. Then, the description of the mechanistic model of the MHF, which plays a key role in the testing environment, is provided and an analysis of the MHF dynamic behavior based on the industrial and simulated data is presented. The design of the mineralogy-driven control strategy for the multiple hearth furnace and its implementation in the simulation environment are also outlined. The analysis of the results is then presented. Furthermore, the extensive sampling campaign for testing the soft sensors and the control strategy logic of the industrial MHF is reported, and the results are analyzed and discussed. Finally, an introduction to Model Predictive Control (MPC) is presented, the design of the Linear MPC framework for the MHF in kaolin calcination is described and discussed, and future research is outlined

Integration of process design and control: A review

There is a large variety of methods in literature for process design and control, which can be classified into two main categories. The methods in the first category have a sequential approach in which, the control system is designed, only after the details of process design are decided. However, when process design is fixed, there is little room left for improving the control performance. Recognizing the interactions between process design and control, the methods in the second category integrate some control aspects into process design. With the aim of providing an exploration map and identifying the potential areas of further contributions, this paper presents a thematic review of the methods for integration of process design and control. The evolution paths of these methods are described and the advantages and disadvantages of each method are explained. The paper concludes with suggestions for future research activities

Nanogenomics and Nanoproteomics Enabling Personalized, Predictive and Preventive Medicine

Since the discovery of the nucleic acid, molecular biology has made tremendous progresses, achieving a lot of results. Despite this, there is still a gap between the classical and traditional medical approach and the molecular world. Inspired by the incredible wealth of data generated by the "omics"-driven techniques and the “high-trouhgput technologies” (HTTs), I have tried to develop a protocol that could reduce the actually extant barrier between the phenomenological medicine and the molecular medicine, facilitating a translational shift from the lab to the patient bedside. I also felt the urgent need to integrate the most important omics sciences, that is to say genomics and proteomics. Nucleic Acid Programmable Protein Arrays (NAPPA) can do this, by utilizing a complex mammalian cell free expression system to produce proteins in situ. In alternative to fluorescent-labeled approaches a new label free method, emerging from the combined utilization of three independent and complementary nanobiotechnological approaches, appears capable to analyze gene and protein function, gene-protein, gene-drug, protein-protein and protein-drug interactions in studies promising for personalized medicine. Quartz Micro Circuit nanogravimetry (QCM), based on frequency and dissipation factor, mass spectrometry (MS) and anodic porous alumina (APA) overcomes indeed the limits of correlated fluorescence detection plagued by the background still present after extensive washes. Work is in progress to further optimize this approach a homogeneous and well defined bacterial cell free expression system able to realize the ambitious objective to quantify the regulatory gene and protein networks in humans. Implications for personalized medicine of the above label free protein array using different test genes and proteins are reported in this PhD thesis

Plantwide Control and Simulation of Sulfur-Iodine Thermochemical Cycle Process for Hydrogen Production

A PWC structure has developed for an industrial scale SITC plant. Based on the performance evaluation, it has been shown that the SITC plant developed via the proposed modified SOC structure can produce satisfactory performance – smooth and reliable operation. The SITC plant is capable of achieving a thermal efficiency of 69%, which is the highest attainable value so far. It is worth noting that the proposed SITC design is viable on the grounds of economic and controllability