Utilisation of biomass for energy production in the North-West Russian forest industry

Traditionally, fossil fuels have always been the major sources of the modern energy production. However prices on these energy sources have been constantly increasing. The utilization of local biomass resources for energy production can substitute significant part of the required energy demand in different energy sectors. The introduction of the biomass usage can easily be started in the forest industry first as it possesses biomass in a large volume. The forest industry energy sector has the highest potential for the fast bioenergy development in the North-West Russia. Therefore, the question concerning rational and effective forest resources use is important today as well as the utilization of the forestry by-products. This work describes and analyzes the opportunities of utilising biomass, mainly, in the form of the wood by-products, for energy production processes in general, as well as for the northwest Russian forest industry conditions. The study also covers basic forest industry processes and technologies, so, the reader can get familiar with the information about the specific character of the biomass utilization. The work gives a comprehensive view on the northwest forest industry situation from the biomass utilisation point of view. By presenting existing large-scale sawmills and pulp and paper mills the work provides information for the evaluation of the future development of CHP investments in the northwest Russian forest industry.

Sustainability of palm oil production and opportunities for Finnish technology and know-how transfer

The global demand for palm oil is growing, thus prompting an increase in the global production particularly in Malaysia and Indonesia. Such increasing demand for palm oil is due to palm oil’s relatively cheap price and versatile advantage both in edible and non-edible applications. Along with the increasing demand for palm oil, particularly for the production of biofuel, is a heated debate on its sustainability. Ecological degradation, climate change and social issues are among the main sustainability issues pressing the whole palm oil industry today. Clean Development Mechanism (CDM) projects fulfilling the imperatives of the Kyoto Protocol are starting to gain momentum in Malaysia as reflected by the increasing registration of CDM projects in the palm oil mills. Most CDM projects in palm oil mills are on waste-to-energy, cocomposting, and methane recovery with the latter being the most common. The study on greenhouse gases (GHG) in the milling process points that biogas collection and energy utilisation has the greatest positive effect on GHG balance. On the other hand, empty fruit bunches (EFB) end-use as energy and high energy efficiency of the mill have the least effect on GHG balance of the mill. The range of direct GHG emissions from the palm oil mill is from 2.5 to 27 gCO2e/MJCPO, while the range of GHG emissions with all indirect and avoided emissions included is from -9 to 29 gCO2e/MJCPO. Comparing this GHG balance result with that of the EU RES-Directive suggests a further check on the values and emissions consideration of the latter.

Tratamento de efluentes industriais por processos oxidativos na presença de ozônio

A large variety of organic and inorganic compounds may be found in wastewater which can contribute to environmental contamination. Oxidation processes with ozone (O3; O3/UV; O3/H2O2; O3/TiO2; O3/Mn+2) and the use of ozone in the pre- or post-treatment of wastewater combined with biological processes has been extensively studied for the treatment of effluents. The aim of this work was to evaluate the potential of the ozonation process in the treatment of several industrial wastewaters, namely effluents from paper mills, and textile, whey (dairy industry), pharmaceutic sand pesticides plants.

Caracterización de las almazaras cooperativas catalanas : análisis interno de la fase industrial o de transformación

En el presente artículo hemos tratado de analizar las características de las almazaras cooperativas catalanas con la finalidad de destacar no solamente sus elementos más importantes de gestión sino también sus principales debilidades. Las cooperativas se consideran instrumentos útiles para acometer políticas de desarrollo económico y bienestar social. A pesar de ello hay un gran debate abierto acerca de la eficiencia de estas organizaciones, que plantean el interrogante de si están en condiciones de competir con éxito en una economía cada vez más abierta, liberalizada y global. A través de las encuestas que hemos realizado al conjunto de las cooperativas oleícolas de Catalunya, hemos podido averiguar sus características distintivas, así como las principales desventajas y problemas a los que se enfrentan. Creemos puede ser de interés analizar las características de estas organizaciones, que tanto desde el punto de vista organizativo como de recursos humanos, como financiero, las hace diferentes de otro tipo de organizaciones pero que sin embargo, han de hacer frente a un mercado cada día más exigente y competitivo

Preparação de amostra de fígado bovino e estudo de micro homogeneidade para a determinação de Cd E Pb por espectrometria de absorção atômica com atomização eletrotérmica e amostragem direta de sólido

This work describes a systematic study for bovine liver sample preparation for Cd and Pb determination by solid sampling electrothermal atomic absorption spectrometry. Samples were prepared using different procedures: (1) drying in a household microwave oven followed by drying in a stove at 60 ºC until constant mass, and (2) freeze-drying. Ball and cryogenic mills were used for grinding. Particle size, sample size and micro sample homogeneity were investigated. All prepared samples showed good homogeneity (He < 10) even for low sample mass, but samples dried in a microwave oven/stove and ground in a ball mill presented the best homogeneity.

Salient Pole Synchronous Machine Modelling in an Industrial Direct Torque Controlled Drive Application

Synchronous motors are used mainly in large drives, for example in ship propulsion systems and in steel factories' rolling mills because of their high efficiency, high overload capacity and good performance in the field weakening range. This, however, requires an extremely good torque control system. A fast torque response and a torque accuracy are basic requirements for such a drive. For large power, high dynamic performance drives the commonly known principle of field oriented vector control has been used solely hitherto, but nowadays it is not the only way to implement such a drive. A new control method Direct Torque Control (DTC) has also emerged. The performance of such a high quality torque control as DTC in dynamically demanding industrial applications is mainly based on the accurate estimate of the various flux linkages' space vectors. Nowadays industrial motor control systems are real time applications with restricted calculation capacity. At the same time the control system requires a simple, fast calculable and reasonably accurate motor model. In this work a method to handle these problems in a Direct Torque Controlled (DTC) salient pole synchronous motor drive is proposed. A motor model which combines the induction law based "voltage model" and motor inductance parameters based "current model" is presented. The voltage model operates as a main model and is calculated at a very fast sampling rate (for example 40 kHz). The stator flux linkage calculated via integration from the stator voltages is corrected using the stator flux linkage computed from the current model. The current model acts as a supervisor that prevents only the motor stator flux linkage from drifting erroneous during longer time intervals. At very low speeds the role of the current model is emphasised but, nevertheless, the voltage model always stays the main model. At higher speeds the function of the current model correction is to act as a stabiliser of the control system. The current model contains a set of inductance parameters which must be known. The validation of the current model in steady state is not self evident. It depends on the accuracy of the saturated value of the inductances. Parameter measurement of the motor model where the supply inverter is used as a measurement signal generator is presented. This so called identification run can be performed prior to delivery or during drive commissioning. A derivation method for the inductance models used for the representation of the saturation effects is proposed. The performance of the electrically excited synchronous motor supplied with the DTC inverter is proven with experimental results. It is shown that it is possible to obtain a good static accuracy of the DTC's torque controller for an electrically excited synchronous motor. The dynamic response is fast and a new operation point is achieved without oscillation. The operation is stable throughout the speed range. The modelling of the magnetising inductance saturation is essential and cross saturation has to be considered as well. The effect of cross saturation is very significant. A DTC inverter can be used as a measuring equipment and the parameters needed for the motor model can be defined by the inverter itself. The main advantage is that the parameters defined are measured in similar magnetic operation conditions and no disagreement between the parameters will exist. The inductance models generated are adequate to meet the requirements of dynamically demanding drives.

Markkinointiviestinnän välittämä imago business-to-business markkinoilla, mielikuvatavoitteena kestävä kehitys

Tässä pro gradu -tutkielmassa tarkasteltiin kansainvälisen metsäteollisuudessa toimivan yrityksen markkinointiviestintää ja sen välittämien imagoviestien siirtymistä business-to-business markkinoilla. Tutkittavat viestit liittyivät kartonkipakkausten kestävän kehityksen ja ympäristöystävällisyyden imagon rakentumiseen. Tutkimuksessa käytettiin kvalitatiivista tutkimusmenetelmää. Tutkimus pohjautui yrityksen teettämän aiemman asiakastutkimuksen aineistoon, jossa selvitettiin pakkauskartonkien mielikuvia kohderyhmässä. Lisäksi tutkittiin imagon viestintää markkinointiviestinnän näkökulmasta. Yrityksen online viestintää verrattiin asiakkaiden vastaavaan viestintään loppukäyttäjille ja selvitettiin siirtyivätkö kestävän kehityksen viestit loppukäyttäjille asti. Tuloksena saatiin osittain yhtenevä viestintä sekä yrityksen asiakkaiden että näiden loppukäyttäjille viestimien teemojen sisällöstä. Tutkimus osoitti, että tärkein viestinnällinen teema on pakkauksen kierrätettävyys. Toisena tärkeänä teemana ilmeni hiilijalanjäljen pienentämisestä viestivät seikat. Nousevana teemana voitiin havaita biohajoavia materiaaleja kohtaan osoitettu kiinnostus. Tutkimuksessa jaettiin vastaajat eri segmentteihin pakkauskartonkien käyttötarkoituksen mukaan ja verrattiin kestävän kehityksen tärkeyttä näiden segmenttien välillä. Segmenteittäin tarkasteltuna suuria eroja ei ollut havaittavissa.

Imatran tehtaiden jätevesipäästöjen hallinta- ja analysointityökalun kehittäminen

Työn tavoitteena oli kehittää Stora Enso Oyj:n Imatran tehtaille Wedge-pohjainen analysointityökalu, jolla voidaan hallita prosessi- ja päästötietojen yhteys nykyistä paremmin. Wedgeen määriteltiin päästömittauksia, olennaisia prosessimittauksia ja tarpeelliset laskennat kuormituksen ennustamiseksi lähtien tuotantoprosessien tilasta. Työssä tehtiin kemialliselle ja biologiselle jätevedenpuhdistamolle meneville jätevesille laskennallisia malleja, joita verrattiin mitattuihin arvoihin. Kemialliselle jätevedenpuhdistamolle meneville jätevesille tehtiin malli jäteveden virtaamalle. Biologiselle jätevedenpuhdistamolle meneville jätevesille tehtiin mallit jäteveden virtaamalle sekä COD-, AOX- ja alkuainekuormituksille. Alkuaineista työhön otettiin mukaan natrium, rikki ja kloori. Teoriaosassa on käsitelty sellu- ja paperitehtaiden vedenkäyttöä, tehtaan eri osastojen jätevesikuormitusta, jäteveden puhdistusmenetelmiä sekä prosessidatan käsittelymenetelmiä. Kokeellisessa osassa on esitelty mitattujen ja laskennallisten mallien yhteyttä. Suurin osa laskennallisista malleista näyttää seuraavan kohtuullisen hyvin mitattuja arvoja. Kokeellisessa osassa on myös havainnollistettu esimerkkien avulla mallien hyödyntämistä. Työn hyötynä on normaalien kuormitusvaihteluiden ja häiriöpäästöjen entistä tarkempi ja nopeampi erottelu. Pitkällä tähtäimellä Wedge-ohjelman avulla pystytään keskittämään jätevesikuormituksen vähentämistoimenpiteet olennaisimpiin kohteisiin.

Water circulations for effective bleaching of high-brightness mechanical pulps

The amount of water available is usually restricted, which leads to a situation where a complete understanding of the process, including water circulations and the influence of water components, is essential. The main aim of this thesis was to clarify the possibilities for the efficient use of residual peroxide by means of water circulation rearrangements. Rearranging water circulations and the reduction of water usage may cause new problems, such as metal induced peroxide decomposition that needs to be addressed. This thesis introduces theoretical methods of water circulations to combine two variables; effective utilization of residual peroxide and avoiding manganese in the alkaline peroxide bleaching stage. Results are mainly based on laboratory and mill site experiments concerning the utilization of residual peroxide. A simulation model (BALAS) was used to evaluate the manganese contents and residual peroxide doses. It was shown that with optimum recirculation of residual peroxide the brightness can be improved or chemical costs can be decreased. From the scientific perspective, it was also very important to discover that recycled peroxide was more effective pre-bleaching agent compared to fresh peroxide. This can be due to the organic acids i.e. per acetic acid in wash press filtrate that have been formed in alkaline bleaching stage. Even short retention time was adequate and the activation of residual peroxide using sodium hydroxide was not necessary. There are several possibilities for using residual peroxide in practice regarding bleaching. A typical modern mechanical pulping process line consist of defibering, screening, a disc filter, a bleach press, high consistency (HC) peroxide bleaching and a wash press. Furthermore there usually is not a particular medium consistency (MC) pre-bleaching stage that includes additional thickening equipment. The most advisable way to utilize residual peroxide in this kind of process is to recycle the wash press filtrate to the dilution of disc filter pulp (low MC pre-bleaching stage). An arrangement such as this would be beneficial in terms of the reduced convection of manganese to the alkaline bleaching stage. Manganese originates from wood material and will be removed to the water phase already in the early stages of the process. Recycling residual peroxide prior to the disc filter is not recommended because of low consistencies. Regarding water circulations, the novel point of view is that, it would be beneficial to divide water circulations into two sections and the critical location for the division is the disc filter. Both of these two sections have their own priority. Section one before the disc filter: manganese removal. Section two after the disc filter: brightening of pulp. This division can be carried out if the disc filter pulp is diluted only by wash press filtrate before the MC storage tower. The situation is even better if there is an additional press after the disc filter, which will improve the consistency of the pulp. This has a significant effect on the peroxide concentration in the MC pre-bleaching stage. In terms of manganese content, it is essential to avoid the use of disc filter filtrate in the bleach press and wash press showers. An additional cut-off press would also be beneficial for manganese removal. As a combination of higher initial brightness and lower manganese content, the typical brightness increase varies between approximately 0.5 and 1% ISO units after the alkaline peroxide bleaching stage. This improvement does not seem to be remarkable, but as it is generally known, the final brightness unit is the most expensive and difficult to achieve. The estimation of cost savings is not unambiguous. For example in GW/TMP mill case 0.6% ISO units higher final brightness gave 10% savings in the costs of bleaching chemicals. With an hypothetical 200 000 ton annual production, this means that the mill could save in the costs of bleaching chemicals more than 400 000 euros per year. In general, it can be said that there were no differences between the behavior of different types of processes (GW, PGW, TMP and BCTMP). The enhancement of recycling gave a similar response in all cases. However, we have to remember that the utilization of residual peroxide in older mills depends a great deal on the process equipment, the amount of water available and existing pipeline connections. In summary, it can be said that processes are individual and the same solutions cannot be applied to all cases.

Kemikaalisekoituksen vaikutus kartongin liimausasteen pienimittakaavaiseen vaihteluun

Tässä diplomityössä tutkittiin massaliimauksen stabiilisuutta kartonkikoneella ja himan sekoituskonseptin muuttamisen vaikutusta liimausasteeseen ja liimausasteen pienimittakaavaiseen vaihteluun konerullan sisällä. Koeajoista saadut tulokset olivat erittäin lupaavia. Koeajoissa annosteltiin hartsia kahdella eri TrumpJet™-installaatiolla. Ensimmäisessä koeajossa hartsi sekoitettiin kaikkiin kolmeen kerrokseen sakean massan syöttölinjaan, ennen pyörrepuhdistuksen vaatimaa laimennusta. Toisessa koeajossa hartsi annosteltiin kolmella TrumpJet-suuttimella kartongin pintakerrokseen konesihdin jälkeen ja muihin kerroksiin perinteisesti sekoitussäiliön. Tuloksista nähtiin, että hartsin syöttö perälaatikon lähestymisvirtaukseen on mahdollista kartongin laadun ja liimausasteen siitä karsimatta. Liimausaste määritettiin Stora Enson spesifisen REP-menetelmän (raw edge penetration) avulla. Koesarjojen välille ei syntynyt merkittäviä eroja reunaimeytymätasoihin, eikä koesarjojen sisäisiin vaihteluihin verrattaessa referensikonerulliin.

Optimization of energy in a pulp mill

This study presents examination of ways to increase power generation in pulp mills. The main purpose was to identify and verify the best ways of power generation growth. The literature part of this study presented operation of energy pulp mill departments, energy consumption and generation by the recovery and power boilers. The second chapter of this part described the main directions for increase of electricity generation rise of black liquor dry solid content, increase of main steam parameters, flue gas heat recovery technologies, feed water and combustion air preheating. The third chapter of the literature part presented possible technical, environment and corrosion risks appeared from described alternatives. In the experimental part of this study, calculations and results of possible models with alternatives was presented. The possible combinations of alternatives were generated in 44 `models of energy pulp mill. The target of this part was define extra electricity generation after alternatives using and estimate profitability of generated models. The calculations were made by computer programme PROSIM. In the conclusions, the results were estimated on the basis of extra electricity generation and equipment design data of models. The profitability of cases was verified by their payback periods and additional incomes.

Vaihtelun vähentäminen kehäpyörien kovasorvauksen vaiheajoissa

Tämän työn tarkoituksena oli selvittää miksi kohdeyrityksen erään avainkomponentin, kehäpyörän, kovasorvauksen vaiheajoissa on niin paljon vaihtelua ja kuinka sitä saataisiin vähennettyä. Samalla pyrittiin lyhentämään keskimääräisiä vaiheaikoja. Tutkimus aloitettiin tuotannon nykytilan kartoituksella, jossa selvitettiin yrityksen toimintatapoja ja tuotannon tehokkuutta heikentäviä ongelmia. Tämän jälkeen aloitettiin varsinainen kehitysprojekti, joka perustui Lean-ajatteluun. Lean-ajattelu on tuotannon kehittämiseen tähtäävä filosofia, jossa pyritään tekemään enemmän vähemmällä, poistamalla tuotannosta kaikki ylimääräinen arvoa lisäämätön toiminta. Tuotantoon pyritään saamaan aikaiseksi tuotteiden jatkuva virtaus tuotantoa tahdistamalla. Erinomaisuutta tavoitellaan jatkuvalla parantamisella. Kohdeyrityksen tuotannon ongelmien tarkemmaksi selvittämiseksi toteutettiin erilaisia seurantoja, niin paikan päällä tuotannossa, kuin automaattista tiedonkeruuohjelmistoa hyväksi käyttäen. Seurantojen tuloksena selvisi, että pääsyyt tuotannon vaiheaikojen vaihteluun löytyvät teknisen järjestelmän sijaan ihmisten asenteista ja osaamisesta. Kun kehitystyön tuloksena toteutetaan muutoksia, kohdataan usein muutosvastarintaa. Tällöin tarvitaan tehokasta muutosjohtamista. Muutostyössä on tärkeä hallita tietoa sen jakamisen lisäksi myös sen keräämisessä. Muutoksiin johtavan tiedon tulee olla aina relevanttia ja faktapohjaista. Muutosjohtamisen tavoitteena on saada aikaiseksi tietoa luova organisaatio, joka kestää itsekritiikkiä ja jolla on poisoppimisen taito. Työsuoritusten parantamiseksi toteutettiin pilottihanke, jossa testattiin tässä työssä kehitettyä palautejärjestelmää. Palaute perustui automaattisen tiedonkeruuohjelmiston keräämään dataan. Samalla selvitettiin työtä hidastaneita ongelmia yhteistyössä työntekijöiden kanssa. Pilottihankkeen tulokset ovat lupaavia, sillä seurannassa olleen kehäpyörämallin viikoittaisten vaiheaikojen keskiarvo laski 32,6 % ja kehäpyörän puolikkaiden kovasorvauksen vaiheaikojen vaihtelut vähenivät 18,1 ja 26,8 %. Tämän tutkimuksen tulosten perusteella päivittäisten työmäärien tarkempaa seurantaa kannattaa jatkaa ja palautejärjestelmää kehittää edelleen.

Micro- and nanostructuring of poly(ethylene-2,6-naphthalate) surfaces, for biomedical applications, using polymer replication techniques

Here we investigate the formation of superficial micro- and nanostructures in poly(ethylene-2,6-naphthalate) (PEN), with a view to their use in biomedical device applications, and compare its performance with a polymer commonly used for the fabrication of these devices, poly(methyl methacrylate) (PMMA). The PEN is found to replicate both micro- and nanostructures in its surface, albeit requiring more forceful replication conditions than PMMA, producing a slight increase in surface hydrophilicity. This ability to form micro/nanostructures, allied to biocompatibility and good optical transparency, suggests that PEN could be a useful material for production of, or for incorporation into, transparent devices for biomedical applications. Such devices will be able to be autoclaved, due to the polymer's high temperature stability, and will be useful for applications where forceful experimental conditions are required, due to a superior chemical resistance over PMMA.

Populaatiodynamiikan perusteet sanoin ja numeroin

Kirjallisuusarvostelu

Diretrizes para a construção de um moinho de bolas para a moagem de sólidos em laboratórios

In this paper, we show the construction of a low-cost, high-quality ball mill for obtaining finely divided powders, with the goal of presenting guidelines for achieving the best results for the milling process. This equipment allows for the adjustment of the size of the mill in order to process different quantities of material. The construction of mechanical and electrical components that provide increased efficiency, the choice of milling medium, and frequent problems experienced with homemade ball mills are discussed.