Ion Exchange Fundamentals and New Challenges

Ion exchange is a stoichiometric phenomenon commonly used in water treatment as an end-of-pipe technique. Such process is highly influenced by mass transfer conditions and may be modeled by adsorption equations. Although widely applied in industries its theory has not been completely understood and depends on the exchanger characteristics. Moreover, competitive systems may add complexity and decrease removal efficiency and exchanger selectivity mainly in dynamic systems. In this chapter some general theory was presented and some detailed examples involving alginate biopolymer, bonechar and zeolite in single and competitive systems were discussed in batch and continuous state

Alginate and Sericin: Environmental and Pharmaceutical Applications

Alginate is a polysaccharide that, for commercial purposes, is extracted exclusively from marine brown algae. In this chapter, we discuss the main sources of alginate and sodium alginate manufacturing, its chemical structure and physicochemical properties, the alginate modifications, and blend formation. We also present applications of alginate and sericin blend in the pharmaceutical and environmental fields as well as case studies

Estudo da cinética de secagem de lodos digeridos provenientes de ETE de indústria de colágeno e gelatina / Study of drying kinetics of digested sludge from a wastewater treatment plant of the collagen and gelatine industry

Os lodos de indústria de gelatina apresentam potencial de utilização como biofertilizante, entretanto possuem elevado teor de umidade (98%). Este trabalho objetivou analisar a influência de três diferentes vazões mássicas do ar de secagem (0,3, 0,4 e 0,5 kg.min-1) para uma temperatura fixa de 110ºC na secagem deste lodo em um secador convectivo. Foram utilizados os modelos de Lewis, Page, Henderson e Pabis e Logarítmico para ajuste aos modelos. Os resultados mostraram que, para a menor vazão, o tempo de secagem foi maior. Já para as duas maiores vazões o tempo de secagem foi o mesmo, mostrando que a velocidade de secagem não apresentou tanta influência. Os modelos apresentaram bons ajustes para as vazões de 0,3 e 0,5 kg.min-1, destacando-se os modelos de Page e Logarítmico, com coeficientes de correlação de aproximadamente 99,85%. Entretanto, para a vazão de 0,4 kg.min-1 os modelos não apresentaram bons ajustes, com coeficientes de correlação de aproximadamente 86,94%.

Analysis of cellulose pulp dryng for the production of card type recycled paper

Orientador: Sandra Cristina dos Santos RochaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia QuimicaResumo: o papel ainda desempenha um fator chave na cultura e na difusão da informação apesar dos grandes avanços tecnológicos. Embora seja produzido a partir de um recurso renovável, como é a madeira, existe tecnologia que permite a sua reutilização a partir de fibras recuperadas. A recic1agem do papel permite uma grande redução na quantidade de resíduos sólidos urbanos, evitando a utilização de recursos naturais tais como a madeira e a água, além de diminuir bastante o consumo energético na indústria papeleira. A produção da polpa de celulose é o grande consumidor de energia no processo de fabricação do papel, seguido da secagem do papel, que é o segundo processo neste tipo de indústria que mais consome energia. A secagem é um processo complexo, de grande importância tanto em termos energéticos como também na qualidade do produto final. Neste contexto, este trabalho teve como proposta analisar a secagem de polpa de celulose a partir de fibras recuperadas para a fabricação de papel cartão recic1ado. Para tanto, projetou-se um secador convectivo, em escala laboratorial, para a secagem da polpa de papel. Foram determinadas as curvas de secagem em função de diferentes condições operacionais e as isotermas de dessorção do papel pelo método dinâmico. Uma análise da qualidade do produto foi realizada para as diferentes condições, além da análise energética do processo. Paralelamente, fez-se um estudo comparativo entre a secagem natural ao ar livre (utilizada em pequenas produções) e a secagem .por convecção forçada no secador projetado. Complementando o estudo da secagem, analisou-se o encolhimento do papel durante a secagem, relacionando-o com as condições operacionais do processo, as características físicas e a qualidade do produto. O secador desenvolvido neste trabalho mostrou-se adequado para a secagem do papel recic1ado tipo cartão, apresentando uma eficiência energética compatível com a dos secadores utilizados na indútria papeleira (24,53%). Verificou-se que o aumento da temperatura e da velocidade do ar de secagem influencia positivamente no processo, reduzindo significativamente o tempo de secagem. No entanto, a qualidade do papel é inferior nas condições mais dráticas de secagem, obtendo-se um produto final com superfície menos uniforme e mais ressecada. No estudo de encolhimento durante a secagem, assim como na análise da qualidade da superfície (JAbstract: Even though the great technological advances, the paper still carries out an important role in the culture and in the diffusion of information. Although it is produced by a renewable source, as the wood, technology allowing paper reuse is available. A selective pick up is necessary for the pulp processing from recovered fibers. The paper recycling allows a great reduction of the amount of urban solid residues, avoiding the use of natural sources as wood and water, besides decreasing a lot the energy consumption in the paper industry. The production of the cellulose pulp is the first great energy consumer in the process of paper production, followed by the paper drying process. The drying is a complex process, of great importance, not only in energy terms, but for the quality of the final product. In this context, this work had the objective to analyze the drying of cellulose pulp made from recovered fibers for the production of card type recycled paper. For this, a convective dryer was projected, in laboratorial scale, for the drying of the paper pulp. The drying curves as a function of different operating conditions were analyzed and the paper dessorption isotherms were determined by the dynamic method. An analysis of the product quality was accomplished for different conditions, as well as the process energy consumption evaluation. A comparative study between the natural drying (used in small productions) and the drying by forced convection was also effectuated. To complement the drying analysis, the shrinkage of the paper was evaluated during the drying and related to the operating conditions, physical characteristics and quality of the product. The dryer developed in this work showed to be appropriate for the drying of the recycled card type paper , presenting energy efficiency compatible with dryers used in paper industries (24,53%). It was verified that the increase of the temperature and velocity of the drying air influenced the process reducing the drying time. However, the quality of the paper is poor for severe operating conditions, leading to a less uniform final product, having a very dry surface. In the paper shrinkage study during drying, as well as in the analysis of the surface quality, similar results were gotten for the papers dried at 70 and 80°C. Significant modifications of structural properties and a low quality of the product were verified for the paper dried at 90°C, indicating a limit to the air temperature for the convective drying of the analyzed recycled papeI. The paper dried at 90°C suffered 15% of surface shrinkage and also 40% of linear and volume reduction during the falling rate drying phase. The paper dried under softer operating conditions (66°C; O,22m/s) presented characteristics similar to the paper naturally dried. Thus, a type card recycled paper can be producted with adequate quality using the convective drier, reducing significantly the necessary time for the drying af the paper sheetDoutoradoEngenharia de ProcessosDoutor em Engenharia Químic

Analise da fluidodinamica de leito de jorro durante o recobrimento de particulas

Orientador: Sandra Cristina dos Santos RochaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia QuimicaResumo: Dentre as diversas operações unitárias que visam a modificação de características superficiais de partículas sólidas, o leito de jorro surge como um substituto para o leito tluidizado, sendo aplicado a uma grande variedade de materiais sólidos com dimensões não muito pequenas. A utilização deste equipamento para o recobrimento de partículas, inicialmente empregado na indústria farmacêutica, tem se mostrado bastante promissora, o que motivou vários estudos envolvendo equações básicas para o dimensionamento e aperfeiçoamento desta tecnologia. Esse trabalho investigou a tluidodinâmica do leito de jorro convencional, para o recobrimento de várias partículas (poliestireno, polipropileno, polietileno de baixa densidade, ABS@, placebo e esferas de vidro), e analisou a intluência das propriedades fisicas das partículas e da suspensão de recobrimento na tluidodinâmica. Utilizou-se uma suspensão polimérica aquosa para os ensaios de recobrimento, empregada em estudos anteriores de recobrimento de placebo (ATAÍDE, 1996), sendo esta caracterizada quanto à tensão superficial, massa específica, reologia e molhabilidade com o sólido (ângulo de contato). Os ensaios tluidodinâmicos com e sem recobrimento foram efetuados em um leito de jorro cônico-cilíndrico já instalado no Laboratório de Fluidodinâmica e Secagem (LFS). Verificou-se que as partículas com um elevado ângulo de contato com a suspensão (PEBD, PS e PP) não apresentaram um recobrimento eficiente e sim apenas a secagem da suspensão. Para as demais partículas (ABS, Placebo e Esferas de vidro), obteve-se recobrimentos com eficiências na faixa de 40 a 90%. A forma geométrica, o ângulo de repouso e a densidade das partículas também apresentaram um efeito na tluidodinâmica do recobrimento, tendo intluência no atrito inter-partícula e na velocidade de circulação das mesmas no ânulo. Determinou-se também a máxima vazão de suspensão que o leito suporta para estas três partículas nas condições de operação estabelecidas a partir de testes preliminares. Juntamente, foram feitas medidas da velocidade dos sólidos no interior do leito, com o objetivo de se correlacionar esta taxa de circulação com o grau de saturação do leito. Verificou-se que a circulação das partículas no leito está relacionada com o grau de saturação do leito. Em leitos com maior grau de saturação, as partículas ficam mais pesadas e a velocidade das mesmas no ânulo decresceAbstract: Among the several unit operations that seek the modification of superficial characteristics of solid partic1es, the spouted bed appears as a substitute for the fluidized bed, to process a great variety of coarse solid materiaIs. The use of this technique for the partic1e coating, initially employed in the pharmaceutical industry, is promising, which motivated several studies involving basic equations for the design and improvement of this technology. This work investigated the fluid-dynamics of the conventional spouted bed during a coating process, using several inert partic1es such as polystirene, polypropilene, polyethilene of low density, ABS@, tablet and glass beads, and analyzed the influence of the physical properties of the partic1es and of the coating suspension on the fluid-dynamics. An aqueous polymeric suspension was used in the coating experiments. The suspension formulation is the same used in previous studies of coating of tablets (A T AÍDE, 1996). The suspension was characterized by the surface tension, specific mass, rheology and contact angle between the suspension and the solid surface. The fluid-dynamics essays with and without coating were made in a conical-cylindrical spouted bed already installed in the Laboratory of Fluid-dynamics and Drying (LFS). It was verified that the partic1es having a high contact angle with the suspension (polystirene, polypropilene and polyethilene of low density) did not present an efficient coating, but only the drying ofthe suspension. For the other partic1es (ABS, Placebo and Glass Spheres), it was obtained coatings with efficiencies in the range of 40 to 90%. The shape, angle of repose and density of partic1es affected the fluid-dynamic during the coating, and also the inter-partic1e friction and the partic1e circulation velocity in the annulus. It was also determined the maximum suspension flow supported by the bed for these three partic1es, at operating conditions established at preliminary tests. The solids velocity inside the spouted bed was also measured in order to correlate this circulation rate with the saturation degree of the bed. It was verified that the circulation of the partic1es in the bed is related with the saturation grade in the bed. In beds with higher saturation degrees, the partic1es are heavier and their velocities in the annulus decreaseMestradoEngenharia de ProcessosMestre em Engenharia Químic

Application of human HAZOP technique adapted to identify risks in Brazilian waste pickers' cooperatives

Waste pickers' cooperatives are an important part of curb side collection, presenting different types of structures and responsible for the sorting and separation of recyclable materials. Within these places, the lack of resources, structure and hygiene are intimately related to the great part of the work accidents and the exposure of these workers to risky situations. Several tools in Security Engineering are being studied to minimize and control risks. Among these techniques, HAZOP (Hazard and Operability study) stands out as one that has proven efficient in managing risks in industrial processes and other areas of study. For the applicability of the technique in this study, interviews were conducted with the co-workers. The data were used to prepare a Preliminary Risk Analysis (PRA) and later to create new guiding words for the modification of HAZOP in order to consider the risk from human aspects in the activities. This work aimed to evaluate the HAZOP applied to evaluate errors related to human aspects in three waste pickers cooperatives in Campinas/SP and to compare the data obtained with the PRA. With the application of the PRA, 189 different deviations were identified and the pre-screening step was the one that most violated workers' risks. With HAZOP and using the content analysis tool to evaluate employees' perceptions, it was possible to identify 209 deviations by having the personal question (45%), followed by the managerial question (29%) as the main causes24624725

Capacity Assesment And Potential For Reuse Of Calcined Bofe Bentonitic Clay For Adsorption Of Nickel

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)This work aims to evaluate different eluents in cycles of nickel adsorption/desorption on calcined Bofe clay. The following eluents were used sequentially for nickel desorption: H2SO4 0.25 mol/L, NaCl 1.0 mol/L, CaCl2 0.10 mol/L, and EDTA 0.10 mol/L. Physical-chemical characterization analyses of Bofe clay samples were carried out under different conditions to evaluate the effect of the remaining metal on the adsorbent submitted to adsorption/desorption cycles. The adsorbent material was characterized by the following techniques: energy dispersive X-ray spectroscopy (EDX), thermogravimetry (TG), differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and N-2 physisorption (BET). Statistica 5.0 was used as a computational tool to adjust the rate quasi-chemical solution to the experimental data of the breakthrough curves. From the new function obtained, breakthrough curves for different bed heights could be also simulated. An increase of the clay surface area and a reduction of real density after the passage of the four eluents were observed. Among the tested eluents, NaCl (1 mol/L) presented the highest percentage of desorption (88.08 %). The nickel adsorption/desorption cycles study showed that Bofe clay retains the same nickel adsorption capacity throughout the four evaluated cycles.94814571465CNPqCAPESFoundation for Research Support of Sao Paulo State, FAPESPConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Cadmium biosorption by alginate extraction waste and process overview in Life Cycle Assessment context

This work evaluated the cadmium biosorption capacity by the alginate extraction residue from brown seaweed Sargassum filipendula, an industry waste which is often discharged into the sea. The biosorption kinetics and equilibrium were investigated, with further analysis of the process thermodynamics. The Mass Transfer in External Film model best described the kinetic data and the rate controlling step is the diffusion through the boundary layer. The kinetic constant values of the model were 0.129, 0.064 and 0.066 1/min for initial concentrations of 1.0, 1.5 and 2.0 mmoL/L, respectively. The isotherms were obtained at four temperatures (293, 303, 313 and 323 K) and were analyzed by Langmuir, Freundlich and Dubinin-Radushkevich models. The system was better described by Freundlich model, and the Dubinin-Radushkevich model suggested that the cadmium uptake is of physical nature. The maximum biosorption capacity obtained at 293 and 303 K were 0.394 and 0.429 mmoL/g, respectively. The thermodynamic parameters indicated that the biosorption of cadmium is spontaneous and exothermic. The simplified LCA showed that the use of dealginated residue would lead to lower environmental impacts for Acidification, Climate Change, Eutrophication, Human Toxicity and Photochemical Oxidation178166175FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2014/05050-