Not available / text

Dynamic modeling is proposed in this paper as a method of developing a computer model to simulate a water softening treatment unit. Information on water softening economics and ion exchange are examined. The development of a dynamic model is oriented toward uniform effluent water quality and operational flexibility. Several methods are presented to determine the reaction rate used in the completely mixed flow reactor's dynamic model. Based on preliminary data the proposed dynamic model would calculate removal rate similar to those found in an existing plant.

No description available.

Digitized by Kansas Correctional Industries

Water in 70 percent of the cities in the United States is hard enough that softening is either required or recommended. It is estimated that approximately 30 percent of all homes in the United States use water softeners. Water softeners, the cation exchange types suited for residential use, exchange sodium for the calcium and magnesium in water. The increase in sodium levels in the softened water caused by cation exchange softening is a direct function of the hardness level of the untreated water. For people who use groundwater, which has a relatively high level of naturally occurring sodium, magnesium and calcium, the additional sodium from cation exchange water softeners may create health hazards for the general population and could adversely affect those who are sensitive to salt or on low sodium diets. To prevent potential health hazards for the general population, no consumption of softened water by cation exchange water softeners should be recommended. If soft water is needed for some practical reasons, a "Separate Water Line System" should be recommended for homeowners. / Graduation date: 1991

A study conducted by the World Health Organization and United Nations Children's Fund, concluded that approximately 768 million people worldwide are not receiving sanitary drinking water suitable for consumption. While there are many water treatment methods, lime softening proves to be one of the more effective approaches as it removes a wide variety of harmful compounds including arsenic, lead, mercury, and cadmium under the correct conditions. The greatest issues with lime softening on a smaller scale include the complexity of the chemistry and need for monitoring. By designing the system for groundwater sources and with a smaller capacity, this thesis hoped to reduce the level of monitoring, chemical expertise, and cost needed for operation. While promising results occurred in the removal of arsenic and total hardness, this project was unable to obtain consistent results and final water samples with pH values between the recommended standard of 6.5 to 8. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / The present work deals about the synthesis and characterization of magnetic zeolites obtained by hydrothermal route using kaolin from Brazilian Northeast as silicon and aluminum source. By means of the X-ray diffraction technique it was possible to identify zeolite LTA and zeolite P1 as major crystalline phases for each synthesis, with low intensity peaks referent to unreacted quartz present in the kaolin used, which is in accordance to the. FTIR spectra; the nanoparticles were identified as magnetite, with low intensity peaks referent to goethite. In scanning electron microscopy, however, it was not possible to morphologically identify these minor components, while the zeolites showed well defined morphologies, presenting unchanged morphology when in the composites form, but with nanoparticles dispersed over their surface, as expected. From transmission electron microscopy it was observed that the nanoparticles were of ca. 50 nm. Magnetic measurements indicated magnetite presence with superior diameter to critical diameter to superparamagnetic particles and remanent magnetization. Thermogravimetric analyses showed for the composites, lower mass loss than compared to the pure zeolites what may be associated to the improvement of its thermal stability. Granulometric distribution indicated nanoparticles agglomeration in variable sizes, while zeolites formed agglomerates of ca. 10 Âm. Water softening was accomplished by using both zeolites, with high efficiency on Ca2+ removal and similar behavior between the zeolite and its respective composite, being the best result observed for zeolite A, with efficiency of 97,95%, reaching equilibrium in the first contact minutes. The dependence on mass studies also showed that zeolite A and its composite presented the best efficiency, whereas zeolite P achieved the same removal levels using corresponding zeolite masses (45 mg). This way, the proposed method for zeolites synthesis proved to be efficient, so that the use of a magnet is capable to attract them, leading their excellent separation from the aqueous medium with its ionic exchange capacity unaffected. / O presente trabalho trata da sÃntese e caracterizaÃÃo de zeÃlitas magnÃticas obtidas por impregnaÃÃo de nanopartÃculas de magnetita a zeÃlitas A e P, sintetizadas por mÃtodo hidrotÃrmico utilizando caulim branco do Nordeste brasileiro como fonte de silÃcio e alumÃnio. Por meio da tÃcnica de difraÃÃo de raios-X foi possÃvel identificar como fases cristalinas majoritÃrias a zeÃlita LTA e P1 para cada sÃntese, com picos de baixa intensidade referentes a quartzo, resistente ao processo tÃrmico de tratamento prÃvio do caulim, bem como nos espectros de infravermelho; as nanopartÃculas foram identificadas como magnetita, havendo ainda indÃcios da presenÃa de goethita em pequena quantidade. Nas anÃlises de microscopia eletrÃnica de varredura, entretanto, nÃo foi possÃvel identificar esses componentes minoritÃrios morfologicamente; enquanto que a morfologia das zeÃlitas mostrou-se bem definida, sem alteraÃÃes apÃs a formaÃÃo dos compÃsitos, apenas com nanopartÃculas espalhadas em sua superfÃcie, como desejado. A partir da microscopia eletrÃnica de transmissÃo, pÃde-se observar melhor a variaÃÃo de tamanho das nanopartÃculas, em mÃdia de 50 nm. Medidas magnÃticas das amostras com essa propriedade indicaram a presenÃa de magnetita com diÃmetro superior ao diÃmetro crÃtico para partÃculas superparamagnÃticas e magnetizaÃÃo remanente. As anÃlises termogravimÃtricas mostraram que a adiÃÃo das nanopartÃculas Ãs zeÃlitas diminuiu sua perda de massa diante do aumento de temperatura e as anÃlises de distribuiÃÃo granulomÃtrica indicaram a aglomeraÃÃo das nanopartÃculas em tamanhos variÃveis, enquanto que as zeÃlitas formaram aglomerados de aproximadamente 10 Âm. Os ensaios de abrandamento de Ãguas mostraram alta eficiÃncia das zeÃlitas em remover Ca2+, com comportamento similar entre a zeÃlita e o seu respectivo compÃsito, encontrando para a zeÃlita A o maior percentual de remoÃÃo, de 97,95 %, atingindo equilÃbrio nos primeiros minutos de aplicaÃÃo. Os estudos de massa tambÃm mostraram a eficiÃncia da zeÃlita A e de seu compÃsito, tendo a zeÃlita P se aproximado dos mesmos nÃveis de remoÃÃo em massas referentes a 45 mg de zeÃlita. Assim, o mÃtodo proposto para sÃntese das zeÃlitas magnÃticas mostrou-se eficiente, de modo que a utilizaÃÃo de um Ãmà à capaz de atraÃ-las facilitando a separaÃÃo do meio apÃs a aplicaÃÃo em meio aquoso e sua capacidade de troca iÃnica nÃo foi afetada.

Capacitive deionization technologies have gained significant attention in recent years. The development and availability of a variety of materials have enabled the growth of research on electrosorption, which makes capacitive deionization increasingly attractive. This technology has a wide range of applications, such as softening, desalination and selective removal, each of which has been the focus of the experimental part of this work. The theoretical part is devoted to the issue of functioning of capacitive deionization, electrode material and especially the specific application. Water desalination is a major issue, given the global shortage of drinking water and the possibility of using capacitive deionization as a competitive method to conventional desalination methods. Conversely, softening and selective removal of ions can pose everyday problems both in the treatment of drinking water or pre-treatment of industrial water and in the treatment of wastewater. In this diploma thesis, it was proved that the method of capacitive deionization can be used to solve all the above problems. Although capacitive deionization is not a commercially available technology in the Czech Republic yet, it can be expected to be used more and more in the future.

This thesis deals with strategies for firms entering the foreign market. In the theoretical part of the work the various strategies and their pros and cons are discussed, together with the dynamics of entering a new market. The analytical part of the work comprises an analysis of the Austrian market and an internal analysis of the company AQUAL Ltd. selected for the practical application. Its SWOT analysis and description of its entrance to a foreign market according to the SMART method are performed. Proposals are given the gradual development of the strategy of entrance, including the reasons for choosing a mixed strategy, and aspects of the operation and management of the company abroad are described; important is the definition of activities of the manager for Austria. Finally, conclusions are given summarizing the prerequisites and expected benefits of the entrance, the goals fulfilled and the contributions provided in this work.

Theme of diploma thesis is the heat transfer medium in heating systems. The thesis is departed to three parts. In the first part, there is a theoretical solution of heat transfer mediums. In the second part, there is a calculation solution of the project. Project solves heating of the apartment building. There are two variants of heating source and water treatment. Those variants are compared. The last part is experimental part. Theme of the experiment is quality of heating water in heating systems.