Decomposição catalítica de óleo de soja em presença de diferentes zeólitas

The catalytic decomposition of soybean oil was studied in a fix bed reactor at 673 and 773 K and using amorphous silica-alumina and the zeolites USY, H-Mordenite and H-ZSM-5 as catalysts. Both the selectivity and the catalytic activity were determined by studying the product composition resulting from the chemical reactions. Physicochemical characteristics of the catalysts were obtained by X-ray fluorescence, Fourier Transform infrared spectroscopy, 29Si and 27Al Nuclear Magnetic Ressonance and textural analysis. The zeolites USY and H-ZSM-5, showing higher Brönsted acidity, yielded products with higher concentration in aromatic hydrocarbons, whereas with both H-Mordenite and amorphous silica-alumina the main products were paraffins.

Calcination of aluminum hydroxide over pressure and residence time

This work investigates the possible effect of pressure and residence time to the reaction of aluminum hydroxide into aluminum oxide. Various pressurized conditions are used as well as the help of various residence times. The aim is to increase the conversion of the reaction with the use of different pressures and residence times. The tests were performed with a laboratory scale fluidized bed reactor at the Outotec R&D Center in Frankfurt. Additional test work such as particle size analysis and differential thermal analysis were also carried out. Some calcined samples were also characterized with X-ray diffraction at the University of Auckland to obtain a reaction pathway when using pressurized conditions. All of the results are then compared with previous results.

Drivers and Barriers of Collaboration in the Value Chain of Paperboard-Packed Consumer Goods

Value chain collaboration has been a prevailing topic for research, and there is a constantly growing interest in developing collaborative models for improved efficiency in logistics. One area of collaboration is demand information management, which enables improved visibility and decrease of inventories in the value chain. Outsourcing of non-core competencies has changed the nature of collaboration from intra-enterprise to cross-enterprise activity, and this together with increasing competition in the globalizing markets have created a need for methods and tools for collaborative work. The retailer part in the value chain of consumer packaged goods (CPG) has been studied relatively widely, proven models have been defined, and there exist several best practice collaboration cases. The information and communications technology has developed rapidly, offering efficient solutions and applications to exchange information between value chain partners. However, the majority of CPG industry still works with traditional business models and practices. This concerns especially companies operating in the upstream of the CPG value chain. Demand information for consumer packaged goods originates at retailers' counters, based on consumers' buying decisions. As this information does not get transferred along the value chain towards the upstream parties, each player needs to optimize their part, causing safety margins for inventories and speculation in purchasing decisions. The safety margins increase with each player, resulting in a phenomenon known as the bullwhip effect. The further the company is from the original demand information source, the more distorted the information is. This thesis concentrates on the upstream parts of the value chain of consumer packaged goods, and more precisely the packaging value chain. Packaging is becoming a part of the product with informative and interactive features, and therefore is not just a cost item needed to protect the product. The upstream part of the CPG value chain is distinctive, as the product changes after each involved party, and therefore the original demand information from the retailers cannot be utilized as such – even if it were transferred seamlessly. The objective of this thesis is to examine the main drivers for collaboration, and barriers causing the moderate adaptation level of collaborative models. Another objective is to define a collaborative demand information management model and test it in a pilot business situation in order to see if the barriers can be eliminated. The empirical part of this thesis contains three parts, all related to the research objective, but involving different target groups, viewpoints and research approaches. The study shows evidence that the main barriers for collaboration are very similar to the barriers in the lower part of the same value chain; lack of trust, lack of business case and lack of senior management commitment. Eliminating one of them – the lack of business case – is not enough to eliminate the two other barriers, as the operational model in this thesis shows. The uncertainty of the future, fear of losing an independent position in purchasing decision making and lack of commitment remain strong enough barriers to prevent the implementation of the proposed collaborative business model. The study proposes a new way of defining the value chain processes: it divides the contracting and planning process into two processes, one managing the commercial parts and the other managing the quantity and specification related issues. This model can reduce the resistance to collaboration, as the commercial part of the contracting process would remain the same as in the traditional model. The quantity/specification-related issues would be managed by the parties with the best capabilities and resources, as well as access to the original demand information. The parties in between would be involved in the planning process as well, as their impact for the next party upstream is significant. The study also highlights the future challenges for companies operating in the CPG value chain. The markets are becoming global, with toughening competition. Also, the technology development will most likely continue with a speed exceeding the adaptation capabilities of the industry. Value chains are also becoming increasingly dynamic, which means shorter and more agile business relationships, and at the same time the predictability of consumer demand is getting more difficult due to shorter product life cycles and trends. These changes will certainly have an effect on companies' operational models, but it is very difficult to estimate when and how the proven methods will gain wide enough adaptation to become standards.

Modeling reaction kinetics and mass transfer in ozonation in water solutions

This dissertation is based on four articles dealing with modeling of ozonation. The literature part of this considers some models for hydrodynamics in bubble column simulation. A literature review of methods for obtaining mass transfer coefficients is presented. The methods presented to obtain mass transfer are general models and can be applied to any gas-liquid system. Ozonation reaction models and methods for obtaining stoichiometric coefficients and reaction rate coefficients for ozonation reactions are discussed in the final section of the literature part. In the first article, ozone gas-liquid mass transfer into water in a bubble column was investigated for different pH values. A more general method for estimation of mass transfer and Henry’s coefficient was developed from the Beltrán method. The ozone volumetric mass transfer coefficient and the Henry’s coefficient were determined simultaneously by parameter estimation using a nonlinear optimization method. A minor dependence of the Henry’s law constant on pH was detected at the pH range 4 - 9. In the second article, a new method using the axial dispersion model for estimation of ozone self-decomposition kinetics in a semi-batch bubble column reactor was developed. The reaction rate coefficients for literature equations of ozone decomposition and the gas phase dispersion coefficient were estimated and compared with the literature data. The reaction order in the pH range 7-10 with respect to ozone 1.12 and 0.51 the hydroxyl ion were obtained, which is in good agreement with literature. The model parameters were determined by parameter estimation using a nonlinear optimization method. Sensitivity analysis was conducted using object function method to obtain information about the reliability and identifiability of the estimated parameters. In the third article, the reaction rate coefficients and the stoichiometric coefficients in the reaction of ozone with the model component p-nitrophenol were estimated at low pH of water using nonlinear optimization. A novel method for estimation of multireaction model parameters in ozonation was developed. In this method the concentration of unknown intermediate compounds is presented as a residual COD (chemical oxygen demand) calculated from the measured COD and the theoretical COD for the known species. The decomposition rate of p-nitrophenol on the pathway producing hydroquinone was found to be about two times faster than the p-nitrophenol decomposition rate on the pathway producing 4- nitrocatechol. In the fourth article, the reaction kinetics of p-nitrophenol ozonation was studied in a bubble column at pH 2. Using the new reaction kinetic model presented in the previous article, the reaction kinetic parameters, rate coefficients, and stoichiometric coefficients as well as the mass transfer coefficient were estimated with nonlinear estimation. The decomposition rate of pnitrophenol was found to be equal both on the pathway producing hydroquinone and on the path way producing 4-nitrocathecol. Comparison of the rate coefficients with the case at initial pH 5 indicates that the p-nitrophenol degradation producing 4- nitrocathecol is more selective towards molecular ozone than the reaction producing hydroquinone. The identifiability and reliability of the estimated parameters were analyzed with the Marcov chain Monte Carlo (MCMC) method. @All rights reserved. No part of the publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior permission of the author.

Determinação espectrofotométrica de aspartame em adoçantes por injeção em fluxo usando um reator em fase sólida contendo fosfato de zinco imobilizado

A flow injection spectrophotometric method was developed for determining aspartame in sweeteners. Sample was dissolved in water and 250 µL of the solution was injected into a carrier stream of 5.0 x 10-5 mol L-1 sodium borate solution. The sample flowed through a column (14 cm x 2.0 mm) packed with Zn3(PO4)2 immobilized in a polymeric matrix of polyester resin and Zn(II) ions were released from the solid-phase reactor by formation of the Zn(II)-aspartame complex. The mixture merged with a stream of borate buffer solution (pH 9.0) containing 0.030 % (m/v) alizarin red S and the Zn(II)-alizarin red complex formed was measured spectrophotometrically at 540 nm. The calibration graph for aspartame was linear in the concentration range from 10 to 80 µg mL-1 with a detection limit of 4 µg mL-1 of aspartame. The RSD was 0.3 % for a solution containing 40 µg mL-1 aspartame (n = 10) and seventy results were obtained per hour. The proposed method was applied for determining aspartame in commercial sweeteners.

Catalytic gasification of glycerol in supercritical water

The conversion of glycerol in supercritical water (SCW) was studied at 510-550 °C and a pressure of 350 bars using both a bed of inert and non-porous ZrO2 particles (hydrothermal experiments), and a bed of a 1% Ru/ZrO2 catalyst. Experiments were conducted with a glycerol concentration of 5 wt% in a continuous isothermal fixed-bed reactor at a residence time between 2 and 10 s. Hydrothermolysis of glycerol formed water-soluble products such as acetaldehyde, acetic acid, hydroxyacetone and acrolein, and gases like H2, CO and CO2. The catalyst enhanced the formation of acetic acid, inhibited the formation of acrolein, and promoted gasification of the glycerol decomposition products. Hydrogen and carbon oxides were the main gases produced in the catalytic experiments, with minor amounts of methane and ethylene. Complete glycerol conversion was achieved at a residence time of 8.5 s at 510 °C, and at around 5 s at 550 °C with the 1 wt% Ru/ZrO2 catalyst. The catalyst was not active enough to achieve complete gasification since high yields of primary products like acetic acid and acetaldehyde were still present. Carbon balances were between 80 and 60% in the catalytic experiments, decreasing continuously as the residence time was increased. This was attributed partially to the formation of methanol and acetaldehyde, which were not recovered and analyzed efficiently in our set-up, but also to the formation of carbon deposits. Carbon deposition was not observed on the catalyst particles but on the surface of the inert zirconia particles, especially at high residence time. This was related to the higher concentration of acetic acid and other acidic species in the catalytic experiments, which may polymerize to form tar-like carbon precursors. Because of carbon deposition, hydrogen yields were significantly lower than expected; for instance at 550 °C the hydrogen yield potential was only 50% of the stoichiometric value.

The Present State and a Development Plan of Cost Accounting in Batch Production of Wind Turbine Gears

The aim of this master’s thesis was to document the present state and to create a development plan for Moventas Wind’s cost accounting. The current cost accounting system was evaluated and most fundamental problems were chosen as areas of focus in development work. The development plan includes both short- and long-term development proposals for problems identified. This report presents two alternative models for product costing. Benchmarking of cost accounting practices and modern cost accounting theories were used in development of cost accounting. It was found that the current cost accounting system functions quite well and the adjustments in unit cost rate calculation have only a minor influence on costs of goods sold. An OEE-based standard cycle concept was also developed and it was found that the implementation of this new system is worthwhile in the long-term.

Heat transfer in superheaters of the bubbling fluidized bed boiler conversions

It is often reasonable to convert old boiler to bubbling fluidized bed boiler instead of building a new one. Converted boiler consists of old and new heat surfaces which must be fitted to operate together. Prediction of heat transfer in not so ideal conditions sets challenges for designers. Two converted boilers situated in Poland were studied on the grounds of acceptance tests and further studies. Calculation of boiler process was performed with boiler design program. Main interest was heat transfer in superheaters and factors affecting it. Theory for heat transfer is presented according to information found from literature. Results obtained from experimental studies and calculations have been compared. With correct definitions calculated parameters corresponded well to measured data at boiler maximum design load. However overload situations revealed to be difficult to model at least without considering changes in the combustion process which requires readjustments to the design program input values.

Instal•lació d'un reactor químic en una indústria farmacèutica

L’objecte del projecte és l’ampliació de la línia de producció d’una indústria farmacèutica dimensionant la fontaneria i instal•lant el reactor químic. Els antecedents són els seguents: en el Desembre de 2013,una indústria farmacèutica decideix ampliar la producciód’una línia existent de treball, instal•lant un reactor químic en paral•lel a la línia deproducció existent. Al Gener de 2014 es decideix adaptar una zona que s’utilitza com a magatzem per fer la nova producció. Per tant s’ha d’adaptar la zona com a Sala Blanca per complir amb la seva nova funcionalitat. A Febrer de 2014 es contracta un enginyer per redactar el projecte de l’adaptació de la Sala Blanca, així com les instal•lacions necessàries per posar en funcionament el Reactor químic adquirit pel client

Program hosting in communications environment with Reactor and thread pool approach

In this thesis concurrent communication event handling is implemented using thread pool approach. Concurrent events are handled with a Reactor design pattern and multithreading is implemented using a Leader/Followers design pattern. Main focus is to evaluate behaviour of implemented model by different numbers of concurrent connections and amount of used threads. Furthermore, model feasibility in a PeerHood middleware is evaluated. Implemented model is evaluated with created test environment which enables concurrent message sending from multiple connections to the system under test. Messages round trip times are measured in the tester application. In the evaluation processing delay into system is simulated and influence of delay to the average round trip time is analysed.

Diagnostiikkamenetelmät höyrykattilan leijukerroksen tilan ja käytettävyysongelmien tunnistamiseksi

Diplomityön tavoitteena oli tutkia höyrykattiloiden leijukerrosten käytettävyysongelmia ja kirjallisuudesta löytyvien diagnostiikkamenetelmien toimivuutta leijukerroksen tilan ja käytettävyysongelmien tunnistamiseksi. Diagnostiikkamenetelmien toimivuutta testattiin VTT:n kiertoleijukoelaitteen prosessimittauksiin perustuen. Analysoinnissa käytettiin prosessimittauksia, jotka ovat yleisesti käytössä energiantuotannon leijukerroskattiloissa. Analysoitavina koeajotapauksina olivat kylmäkokeet partikkelikokojakaumaltaan vaihtelevalle leijutusmateriaalille, tuhkapartikkelien aiheuttama petimateriaalin karkeneminen ja agglomeroituminen, sekä vaihtelevien ajoarvojen vaikutus leijukerroksen hydrodynaamiseen käyttäytymiseen. Kokeellisesta osiosta saaduista tuloksista selvisi leijutusilman tilavuusvirran, petimassan ja partikkelikoon vaikutus analysoitavaan prosessimittaukseen. Tuloksista oli havaittavissa myös kiertävän petimateriaalin ja pohjapedin osuuksien vaikutus mitattuun painesignaaliin. Petipartikkelien agglomeroitumisen ja karkenemisen todettiin lisäävän kiertoleijukoelaitteistossa nousuputken pohjapedin määrää suhteessa kiertävään petimateriaaliin, mikä voitiin havaita painemittauksista.

A three dimensional study of heat transfer in a supercritical circulating fluidized bed combustor

From the boiler design point of view, it is imperative to know and understand the operation of the boiler. Since comprehensive measurement of a large furnace is impossible, the furnace can be modeled in order to study its behavior and phenomena. This requires the used model to be validated to correspond with the physical furnace behavior. In this thesis, a three dimensional furnace model is validated to match a bituminous coal utilizing, supercritical once-through circulating fluidized bed combustor based on measurement data. The validated model is used for analyzing the furnace heat transfer. Other heat transfer analysis methods are energy balance method based on tube surface temperature measurements and a method based on measured temperature difference between the tube crest and the fin. The latter method was developed in the thesis using Fluent-software. In the theory part, literature is reviewed and the fundamental aspects of circulating fluidized bed are discussed. These aspects are solid particle behavior in fluidization known as hydrodynamics, behavior of fuel and combustion and heat transfer. Fundamental aspects of modeling are also presented.

Model-based study of a chemical-looping combustion process

Chemical-looping combustion (CLC) is a novel combustion technology with inherent separation of the greenhouse gas CO2. The technique typically employs a dual fluidized bed system where a metal oxide is used as a solid oxygen carrier that transfers the oxygen from combustion air to the fuel. The oxygen carrier is looping between the air reactor, where it is oxidized by the air, and the fuel reactor, where it is reduced by the fuel. Hence, air is not mixed with the fuel, and outgoing CO2 does not become diluted by the nitrogen, which gives a possibility to collect the CO2 from the flue gases after the water vapor is condensed. CLC is being proposed as a promising and energy efficient carbon capture technology, since it can achieve both an increase in power station efficiency simultaneously with low energy penalty from the carbon capture. The outcome of a comprehensive literature study concerning the current status of CLC development is presented in this thesis. Also, a steady state model of the CLC process, based on the conservation equations of mass and energy, was developed. The model was used to determine the process conditions and to calculate the reactor dimensions of a 100 MWth CLC system with bunsenite (NiO) as oxygen carrier and methane (CH4) as fuel. This study has been made in Oxygen Carriers and Their Industrial Applications research project (2008 – 2011), funded by the Tekes – Functional Material program. I would like to acknowledge Tekes and participating companies for funding and all project partners for good and comfortable cooperation.

Cromatografia em leito móvel simulado na produção de substâncias enantiomericamente puras ou enriquecidas em larga escala

There is great interest nowadays in the use of preparative liquid chromatography as an effective tool for the production of enantiomerically pure, or enriched, compounds for the pharmaceutical industry. To make the chromatographic process economically attractive, attention is now focused on the choice of the chromatographic operating mode to minimize eluent consumption and to maximize productivity. Among the alternatives to the traditional batch chromatography, attention is now shifting towards simulated moving bed (SMB) technologies and a review covering the latest developments in this area seems timely. Several aspects of this important analytical technique are presented and details concerning the SMB technology for process optimization are outlined.

Non conventional biological treatment based on Trametes versicolor for the elimination of recalcitrant anticancer drugs in hospital wastewater

This work presents a study about the elimination of anticancer drugs, a group of pollutants considered recalcitrant during conventional activated sludge wastewater treatment, using a biological treatment based on the fungus Trametes versicolor. A 10-L fluidized bed bioreactor inoculated with this fungus was set up in order to evaluate the removal of 10 selected anticancer drugs in real hospital wastewater. Almost all the tested anticancer drugs were completely removed from the wastewater at the end of the batch experiment (8 d) with the exception of Ifosfamide and Tamoxifen. These two recalcitrant compounds, together with Cyclophosphamide, were selected for further studies to test their degradability by T. versicolor under optimal growth conditions. Cyclophosphamide and Ifosfamide were inalterable during batch experiments both at high and low concentration, whereas Tamoxifen exhibited a decrease in its concentration along the treatment. Two positional isomers of a hydroxylated form of Tamoxifen were identified during this experiment using a high resolution mass spectrometry based on ultra-high performance chromatography coupled to an Orbitrap detector (LTQ-Velos Orbitrap). Finally the identified transformation products of Tamoxifen were monitored in the bioreactor run with real hospital wastewater