957 resultados para genuine saving


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Forskningens syfte var att bidra med en ny kunskapssyntes om vad det innebär att leda förändring ur ett vårdvetenskapligt perspektiv. Vårdledaren har, speciellt vid större förändringar inom organisationen, en stor betydelse för hur vårdandet förvaltas genom att hålla den vårdande traditionen levande och genom formningen av den vårdande kulturen och vårdgemenskapen. Den övergripande hermeneutiska forskningsansatsen med tillämpning av metodologisk triangulering har influerats av Gadamers, Ricoeurs och Ödmans syn på hermeneutik med förståelse och förklaring som kompletterar varandra. Forskningens övergripande frågeställning ”Vad innebär det att leda förändring ur ett vårdvetenskapligt perspektiv?” förankrades i de fyra underliggande frågeställningarna. Den första frågeställningen berörde meningsinnehållet i begreppet förändring samt dess gestaltning. Metoden var en hermeneutisk begreppsbestämning på en ontologisk och kontextuell nivå enligt Koorts metod för begreppsbestämning. Genom en personalenkät undersöktes personalens åsikter (totalt 597 personer) om den kommande fusionen och förändringen samt deras förväntningar på ledarna under förändringsprocessen för att få svar på vad förutsättningarna var för en förändring eller förändringsprocess med avsedda mål och effekter. Svaret på hur vårdledaren och dennes uppgifter gestaltades vid en förändring samt hur vårdledarna uppfattade förändring och den kommande förändringsprocessen erhölls genom djupintervjuer med vårdledare (17). Av resultatet framgår att vårdledaren leder förändring genom att leda relationer, processer och kultur och genom ett stödjande, reflekterande och kulturbärande ledarskap med syftet att åstadkomma en verklig och hållbar förändring. För att åstadkomma en verklig och hållbar förändring, dvs. en inre omgestaltning och omdaning som vardande, förutsätts dock att både tankemönster och handlanden förändras. Riktningen och insatserna för förändringen skall ha sin grund i en tydlig och meningsfull målsättning och vision utgående från en gemensam värdegrund. En arena för dialog borde utvecklas så att förändringens liksom även vårdandets vision och mission förankras och utvecklas till handling och förändring. Vårdledarens primära uppgift eller mission var att tillhandahålla varje individuell patient en god vård. Den primära missionen var med andra ord att med ansvarsfullhet tjäna vårdandet sak utgående från ett etiskt förhållningssätt. I tjänande av vårdandets sak fanns dock en tillit till att förändringen gagnar patienten och hans eller hennes vård, men vårdledarnas anpassning till förändringen var utan djupare engagemang. Vårdledarna kände även en oro för sitt uppdrag som vårdledare, vårdarbetets ställning och mandatet som patientens advokat. Vårdledaren är också en kulturbärare, vilket innebär att även kulturen har betydelse under en förändringsprocess. Genom att leda kulturen skapar vårdledaren en öppen, bekräftande och evidensbaserad atmosfär med centrala värderingar som ger uttryck för den rådande andan och kulturen.

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Main objective of this research was to find suitable polymeric ultrafiltration membranes with high retentions, good capacities and low fouling tendencies for the E2- and EP-effluent ultrafiltration. Purpose was to treat alkaline bleaching effluents with ultrafiltration in a way that permeates of the filtrations could be recycled back to process and the consumption of fresh water in the pulp mill could be reduced significantly. In the theoretical part of this work the challenges set by the pulp and paper indus-try processes for membranes were examined. An overview of the membrane tech-nology in the pulp industry was also provided. In addition process conditions in the chemical pulp bleaching and properties of bleaching effluents were discussed in literature study. In experimental part the E2- and EP-stage bleaching effluents from Stora Enso Imatra kraft pulp mill were ultrafiltered with CR250- and CR200-filters. Suitable membranes for ultrafiltration were chosen after screening experiments. Concentra-tion experiment was made for the E2-effluent in order to estimate water saving potential. The E2-effluent was finally ultrafiltered in the pulp mill in order to test the feasibility of ultrafiltration in a real industrial environment. Good membrane for the EP-effluent ultrafiltration based on the EP-screening ex-periments was polyethersulfone membrane UP020 with cut-off value of 20 000 Da. Polysulfone membrane UFX05 with cut-off value of 5 000 Da was promising membrane for the ultrafiltration of the E2-effluent. Based on the concentration filtration of the E2-effluent with UFX05 membrane the water saving potential could be 2.2 m3/Adt for the industrial scale ultrafiltration process. Retention re-sults, such as average COD retention of 60 %, from the trial filtration at the pulp mill with UFX05 membrane were modest compared to the screening experiments, where average COD retention was 75 %. Therefore tighter ultrafiltration mem-branes should be tested for the ultrafiltration of the E2-effluent. The UP020 mem-brane seemed to be suitable for the ultrafiltration of the EP-effluent however con-centration and pilot scale ultrafiltration experiments are needed to verify this.

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Työ käsittelee ulkoistettujen logistiikkapalveluiden kustannusrakennetta sekä niiden mahdollista säästöpotentiaalia. Asetettu säästötavoite on kymmenen prosenttia. Logistiikkakustannukset muodostuvat pääpiirteissään ostorahdista, myyntirahdista, varastojen ja tuotantolaitoksen välisistä rahdeista sekä ulkopuolisilta toimijoilta vuokratuista varastoista. Työn teettävän yrityksen logistiikkakustannusten kustannusjakaumat tulee selvittää tekijöittäin perinpohjaisesti. Kustannustekijöiden määrittämisen jälkeen kustannukset on kohdistettu kullekin tekijälle yksitellen. Kustannustietojen osalta tutkimus kohdistui yrityksen omaan raportointiin, kirjanpitoon, palveluita tarjoavien toimijoiden laskutukseen sekä toimijoiden rahtien ja varastoinnin dokumentointeihin. Työn teoriaosuus pohjautuu tieteellisiin artikkeleihin ja kirjallisuuteen. Tutkimuskohteiden ja asetetun säästötavoitteen pohjalta on haarukoitu keinoja säästötavoitteen saavuttamiseksi. Kustannussäästöjä on haettu kahta eri reittiä pitkin. Ensimmäiseksi säästöjä haetaan organisaation oman toiminnan tehostamisella ja sitä kautta löytyvillä muutoksilla nykyiseen toimintamalliin nähden. Toinen tutkimuspolku on säästöjen hakeminen investointeja tekemällä. Oman toiminnan tehostamisen toimenpiteillä sekä investointeja tekemällä on mahdollista päästä asetettuun säästötavoitteeseen koskien yrityksen logistiikkakustannuksia.

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Liikenneturvallisuus syntyy eri osapuolten toiminnan ja yhteistyön tuloksena. Poliitikot päättävät yhteiskunnan suunnittelusta ja liikennejärjestelmästä, suunnittelijat toteuttavat poliitikkojen tekemiä päätöksiä, virkamiehet laativat lakiehdotuksia ja sääntöjä, ELY-keskus ja kunnat vastaavat teistä ja niiden kunnosta, poliisi valvoo liikennesääntöjen noudattamista, Liikenneturva tiedottaa ja kouluttaa, yritykset, yhteisöt ja yksityiset ihmiset tilaavat ja käyttävät kuljetuspalveluja ja kaikki kuntalaiset osallistuvat liikenteeseen. Liikenneturvallisuussuunnitelma toimii työkaluna Varsinais-Suomen ja Satakunnan liikenneturvallisuustyössä. Alueellisen liikenneturvallisuustyön nollavisio ja tavoitteet asetettiin valtakunnallisen liikenneturvallisuussuunnitelman, alueen nykytila-analyysin sekä suunnitelman laadinnan aikana sidosryhmien kanssa käydyn keskustelun pohjalta. Nollavision mukaan kenenkään ei tarvitse kuolla tai loukkaantua vakavasti liikenteessä. Lisäksi visiona on vastuullinen liikkuminen, joka myös koetaan turvalliseksi. Seitsemän kohdan ohjelmaan nollavision toteuttamiseksi on tiivistetty tärkeimmät toimet. Yksilöityihin toimenpiteisiin on kirjattu maankäytön suunnitteluun, kestävään liikkumiseen, liikenneympäristöön ja liikennekäyttäytymiseen liittyviä toimenpiteitä. Lisäksi liikenneturvallisuusyhteistyöhön kohdistuvia toimenpiteitä sisältyy suunnitelmaan. Toimenpiteiden toteuttamisen vastuu- ja yhteistyötahoja on useita. Toimenpiteet kohdistuvat alueen tielläliikkujiin, organisaatioihin ja päätöksentekijöihin. Pitkän aikavälin ja valtakunnallisen tason toimenpiteet edesauttavat liikenneturvallisuuden kehittymistä toivottuun suuntaan. Vaikutustarkastelu osoittaa, että asetettujen tavoitteiden saavuttaminen vaatii laajaa keinovalikoimaa, usean toimijan välistä yhteistyötä sekä resursseja liikenneturvallisuustyöhön. Tämä liikenneturvallisuussuunnitelma haastaa eri hallinnonalat, viranomaiset, järjestöt ja yritykset omalta osaltaan toteuttamaan toimia, jotka vievät kohti nollavisiota. Suunnitelman toteutuminen edellyttää, että sillä on kuntien ja päättäjien tuki. Varsinais-Suomen ja Satakunnan liikenteen tulevaisuus kehittyy suunnitelman mukaisesti, jos liikenteen vastuunkantajat sitoutuvat suunnitelman vision periaatteisiin ja pitävät elämää suojelevia arvoja toimintansa perustana.

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Transportation of fluids is one of the most common and energy intensive processes in the industrial and HVAC sectors. Pumping systems are frequently subject to engineering malpractice when dimensioned, which can lead to poor operational efficiency. Moreover, pump monitoring requires dedicated measuring equipment, which imply costly investments. Inefficient pump operation and improper maintenance can increase energy costs substantially and even lead to pump failure. A centrifugal pump is commonly driven by an induction motor. Driving the induction motor with a frequency converter can diminish energy consumption in pump drives and provide better control of a process. In addition, induction machine signals can also be estimated by modern frequency converters, dispensing with the use of sensors. If the estimates are accurate enough, a pump can be modelled and integrated into the frequency converter control scheme. This can open the possibility of joint motor and pump monitoring and diagnostics, thereby allowing the detection of reliability-reducing operating states that can lead to additional maintenance costs. The goal of this work is to study the accuracy of rotational speed, torque and shaft power estimates calculated by a frequency converter. Laboratory tests were performed in order to observe estimate behaviour in both steady-state and transient operation. An induction machine driven by a vector-controlled frequency converter, coupled with another induction machine acting as load was used in the tests. The estimated quantities were obtained through the frequency converter’s Trend Recorder software. A high-precision, HBM T12 torque-speed transducer was used to measure the actual values of the aforementioned variables. The effect of the flux optimization energy saving feature on the estimate quality was also studied. A processing function was developed in MATLAB for comparison of the obtained data. The obtained results confirm the suitability of this particular converter to provide accurate enough estimates for pumping applications.

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Pumping systems account for over 20 % of all electricity consumption in European industry. Optimization and correct design of such systems is important and there is a reasonable amount of unrealized energy saving potential in old pumping systems. The energy efficiency and therefore also the energy consumption of a pumping system heavily depends on the correct dimensioning and selection of devices. In this work, a graphical optimization tool for pumping systems is developed in Matlab programming language. The tool selects optimal pump, electrical motor and frequency converter for existing pumping process and calculates the life cycle costs of the whole system. The tool could be used as an aid when choosing the machinery and to analyze the energy consumption of existing systems. Results given by the tool are compared to the results of laboratory tests. The selection of pump and motor works reasonably well, but the frequency converter selection still needs development

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The objective of this thesis was to examine the potential of multi-axis solutions in packaging machines produced in Europe. The definition of a multi-axis solution in this study is a construction that uses a common DC bus power supply for different amplifiers running the axes and the intelligence is centralized into one unit. The cost structure of a packaging machine was gained from an automation research, which divided the machines according to automation categories. The automation categories were then further divided into different sub-components by evaluating the ratio of multi-axis solutions compared to other automation components in packaging machines. A global motion control study was used for further information. With the help of the ratio, an estimation of the potential of multi-axis solutions in each country and packaging machine sector was completed. In addition to the research, a specific questionnaire was sent to five companies to gain information about the present situation and possible trends in packaging machinery. The greatest potential markets are in Germany and Italy, which are also the largest producers of packaging machinery in Europe. The greatest growth in the next few years will be seen in Turkey where the annual growth rate equals the general machinery production rate in Asia. The greatest market potential of the Nordic countries is found in Sweden in 35th position on the list. According to the interviews, motion control products in packaging machines will retain their current power levels, as well as the number of axes in the future. Integrated machine safety features together with a universal programming language are the desired attributes of the future. Unlike generally in industry, the energy saving objectives are and will remain insignificant in the packaging industry.

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In accordance with the Moore's law, the increasing number of on-chip integrated transistors has enabled modern computing platforms with not only higher processing power but also more affordable prices. As a result, these platforms, including portable devices, work stations and data centres, are becoming an inevitable part of the human society. However, with the demand for portability and raising cost of power, energy efficiency has emerged to be a major concern for modern computing platforms. As the complexity of on-chip systems increases, Network-on-Chip (NoC) has been proved as an efficient communication architecture which can further improve system performances and scalability while reducing the design cost. Therefore, in this thesis, we study and propose energy optimization approaches based on NoC architecture, with special focuses on the following aspects. As the architectural trend of future computing platforms, 3D systems have many bene ts including higher integration density, smaller footprint, heterogeneous integration, etc. Moreover, 3D technology can signi cantly improve the network communication and effectively avoid long wirings, and therefore, provide higher system performance and energy efficiency. With the dynamic nature of on-chip communication in large scale NoC based systems, run-time system optimization is of crucial importance in order to achieve higher system reliability and essentially energy efficiency. In this thesis, we propose an agent based system design approach where agents are on-chip components which monitor and control system parameters such as supply voltage, operating frequency, etc. With this approach, we have analysed the implementation alternatives for dynamic voltage and frequency scaling and power gating techniques at different granularity, which reduce both dynamic and leakage energy consumption. Topologies, being one of the key factors for NoCs, are also explored for energy saving purpose. A Honeycomb NoC architecture is proposed in this thesis with turn-model based deadlock-free routing algorithms. Our analysis and simulation based evaluation show that Honeycomb NoCs outperform their Mesh based counterparts in terms of network cost, system performance as well as energy efficiency.

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Tämä tutkielma käsittelee kaupallisten yhtiöiden julkaisemia lehdistötiedotteita, joissa ilmoitetaan henkilöstövähennyksistä. Erityisenä tutkimuskohteena ovat lehdistötiedotteiden informatiiviset ja promotionaaliset päämäärät ja tarkoitukset sekä näiden päämäärien ja tarkoitusten ilmentyminen tekstin retorisen rakenteen, valittujen retoristen strategioiden sekä leksikaalisten ja kieliopillisten valintojen kautta. Tutkimuksen aineisto koostuu 50 englanninkielisestä lehdistötiedotteesta, jotka sisältävät ilmoituksen henkilöstövähennyksistä. Lehdistötiedotteet kerättiin yritysten verkkosivuilta. Tutkimuksen teoreettisena viitekehityksenä toimivat soveltavan kielentutkimuksen alalla erityisesti ammattikielentutkimuksessa (ESP, English for Specific Purposes) laajalti käytetty Swalesin (1990) tekstilajia (genre) koskeva määritelmää ja Bhatian (1993) kehittämä geneerisen analyysin malli. Ennen aineiston kielitieteellistä analysointia tutkimuksessa perehdyttiin Bhatian (1993) mallin mukaisesti lehdistötiedotteiden historiaan, kohdeyleisöihin, diskurssiyhteisöön ja sen tuottamiin muihin tekstilajeihin, aikaisempiin lehdistotiedotteita käsitteleviin kielitieteellisiin tutkimuksiin sekä erityisesti yritysten henkilövähennyksiin liittyvään tilannekontekstiin. Kielitieteellisessä analyysissä tutkittavista teksteistä tunnistettiin kahdeksan retorista vaihetta (move), jotka olivat tyypillisiä tutkituille teksteille. Kunkin retorisen vaiheen yksittäiset ilmentymät koottiin yhteen erillisiksi aineistoiksi, joista pyrittiin tunnistamaan kullekin vaiheelle tyypilliset retoriset strategiat sekä toistuvat leksikaaliset ja kieliopilliset valinnat. Tutkimuksessa todettiin, että vaikka tutkittujen lehdistötiedotteiden pääasiallinen tarkoitus oli yhtiön toiminnasta tiedottaminen, niillä oli myös promotionaalinen päämäärä, joka ilmeni mm. pyrkimyksenä välittää yhtiöstä mahdollisimman positiivinen kuva eri kohdeyleisöille, erityisesti sijoittajille. Tämän positiivisen kuvan välittämiseen käytettyjä keinoja olivat mm. odotettavissa olevien saavutusten korostaminen, ulkoisten tekijöiden nimeäminen nykyisen tilanteen aiheuttajaksi, passiivin käyttö sekä erilaiset yrityksen julkisen kuvan säilyttämiseen pyrkivät (face-saving) strategiat.

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The present thesis discusses the coherence or lack of coherence in the book of Numbers, with special regard to its narrative features. The fragmented nature of Numbers is a well-known problem in research on the book, affecting how we approach and interpret it, but to date there has not been any thorough investigation of the narrative features of the work and how they might contribute to the coherence or the lack of coherence in the book. The discussion is pursued in light of narrative theory, and especially in connection to three parameters that are typically understood to be invoked in the interpretation of narratives: 1) a narrative paradigm, or ‘story,’ meaning events related to each other temporally, causally, and thematically, in a plot with a beginning, middle, and end; 2) discourse, being the expression plane of a narrative, or the devices that an author has at hand in constructing a narrative; 3) the situation or languagegame of the narrative, prototypical examples being factual reports, which seeks to depict a state of affairs, and storytelling narratives, driven by a demand for tellability. In view of these parameters the present thesis argues that it is reasonable to form four groups to describe the narrative material of Numbers: genuine narratives (e.g. Num 12), independent narrative sequences (e.g. Num 5:1-4), instrumental scenes and situations (e.g. Num 27:1-5), and narrative fragments (e.g. Num 18:1). These groups are mixed throughout with non-narrative materials. Seen together, however, the narrative features of these groups can be understood to create an attenuated narrative sequence from beginning to end in Numbers, where one thing happens after another. This sequence, termed the ‘larger story’ of Numbers, concerns the wandering of Israel from Sinai to Moab. Furthermore, the larger story has a fragmented plot. The end-point is fixed on the promised land, Israel prepares for the wandering towards it (Num 1-10), rebels against wandering and the promise and is sent back into the wilderness (Num 13-14), returns again after forty years (Num 21ff.), and prepares for conquering the land (Num 22-36). Finally, themes of the promised land, generational succession, and obedience-disobedience, operate in this larger story. Purity is also a significant theme in the book, albeit not connected to plot in the larger story. All in all, sequence, plot, and theme in the larger story of Numbers can be understood to bring some coherence to the book. However, neither aspect entirely subsumes the whole book, and the four groups of narrative materials can also be understood to underscore the incoherence of the work in differentiating its variegated narrative contents. Numbers should therefore be described as an anthology of different materials that are loosely connected through its narrative features in the larger story, with the aim of informing Israelite identity by depicting a certain period in the early history of the people.

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Information gained from the human genome project and improvements in compound synthesizing have increased the number of both therapeutic targets and potential lead compounds. This has evolved a need for better screening techniques to have a capacity to screen number of compound libraries against increasing amount of targets. Radioactivity based assays have been traditionally used in drug screening but the fluorescence based assays have become more popular in high throughput screening (HTS) as they avoid safety and waste problems confronted with radioactivity. In comparison to conventional fluorescence more sensitive detection is obtained with time-resolved luminescence which has increased the popularity of time-resolved fluorescence resonance energy transfer (TR-FRET) based assays. To simplify the current TR-FRET based assay concept the luminometric homogeneous single-label utilizing assay technique, Quenching Resonance Energy Transfer (QRET), was developed. The technique utilizes soluble quencher to quench non-specifically the signal of unbound fraction of lanthanide labeled ligand. One labeling procedure and fewer manipulation steps in the assay concept are saving resources. The QRET technique is suitable for both biochemical and cell-based assays as indicated in four studies:1) ligand screening study of β2 -adrenergic receptor (cell-based), 2) activation study of Gs-/Gi-protein coupled receptors by measuring intracellular concentration of cyclic adenosine monophosphate (cell-based), 3) activation study of G-protein coupled receptors by observing the binding of guanosine-5’-triphosphate (cell membranes), and 4) activation study of small GTP binding protein Ras (biochemical). Signal-to-background ratios were between 2.4 to 10 and coefficient of variation varied from 0.5 to 17% indicating their suitability to HTS use.

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Fan systems are responsible for approximately 10% of the electricity consumption in industrial and municipal sectors, and it has been found that there is energy-saving potential in these systems. To this end, variable speed drives (VSDs) are used to enhance the efficiency of fan systems. Usually, fan system operation is optimized based on measurements of the system, but there are seldom readily installed meters in the system that can be used for the purpose. Thus, sensorless methods are needed for the optimization of fan system operation. In this thesis, methods for the fan operating point estimation with a variable speed drive are studied and discussed. These methods can be used for the energy efficient control of the fan system without additional measurements. The operation of these methods is validated by laboratory measurements and data from an industrial fan system. In addition to their energy consumption, condition monitoring of fan systems is a key issue as fans are an integral part of various production processes. Fan system condition monitoring is usually carried out with vibration measurements, which again increase the system complexity. However, variable speed drives can already be used for pumping system condition monitoring. Therefore, it would add to the usability of a variablespeed- driven fan system if the variable speed drive could be used as a condition monitoring device. In this thesis, sensorless detection methods for three lifetime-reducing phenomena are suggested: these are detection of the fan contamination build-up, the correct rotational direction, and the fan surge. The methods use the variable speed drive monitoring and control options for the detection along with simple signal processing methods, such as power spectrum density estimates. The methods have been validated by laboratory measurements. The key finding of this doctoral thesis is that a variable speed drive can be used on its own as a monitoring and control device for the fan system energy efficiency, and it can also be used in the detection of certain lifetime-reducing phenomena.

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Tämän diplomityön tavoitteena oli tutkia ympäristömyönteisiä energiatehokkaita ratkaisuja, joita voitaisiin hyödyntää Kymenlaakson keskussairaalan rakennus- ja saneeraushankkeessa. Energiatehokkaiden ratkaisujen mahdollistamista vuotuisista käyttökustannussäästöistä laskettiin investointipotentiaali, jota voidaan hyödyntää saneerausinvestoinnin rahoituksessa. Työ jakautuu teoreettiseen kirjallisuusselvitykseen ja empiiriseen osuuteen, joka on toiminta-analyyttinen case-tutkimus. Investointipotentiaalin määrittämiseksi muodostettiin kolme skenaariota eritasoisisten energiankulutusta vähentävien toimenpiteiden ja tutkimustulosten sekä toteutusvaiheessa olevan saneeraushankeen pohjalta. Skenaariot muodostuivat erilaisista lämmön- ja sähkönkulutuksen vähentämisen yhdistelmistä. Investointipotentiaali saatiin laskemalla nykyarvo vuotuisista tulevaisuuden energiankulutuksen käyttökustannussäästöistä. Työn tuloksina esitettiin energiatehokkuutta parantavia ratkaisuja sekä kolme erisuuruisten energiankulutuksen vähennysyhdistelmien aikaansaamaa käyttökustannus-säästöistä syntyvää investointipotentiaaliratkaisua. Tutkimustietoa voidaan hyödyntää alkavassa sairaalan rakennus- ja saneerausinvestoinnin suunnittelutyössä.

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This doctoral thesis describes the development work performed on the leachand purification sections in the electrolytic zinc plant in Kokkola to increase the efficiency in these two stages, and thus the competitiveness of the plant. Since metallic zinc is a typical bulk product, the improvement of the competitiveness of a plant was mostly an issue of decreasing unit costs. The problems in the leaching were low recovery of valuable metals from raw materials, and that the available technology offered complicated and expensive processes to overcome this problem. In the purification, the main problem was consumption of zinc powder - up to four to six times the stoichiometric demand. This reduced the capacity of the plant as this zinc is re-circulated through the electrolysis, which is the absolute bottleneck in a zinc plant. Low selectivity gave low-grade and low-value precipitates for further processing to metallic copper, cadmium, cobalt and nickel. Knowledge of the underlying chemistry was poor and process interruptions causing losses of zinc production were frequent. Studies on leaching comprised the kinetics of ferrite leaching and jarosite precipitation, as well as the stability of jarosite in acidic plant solutions. A breakthrough came with the finding that jarosite could precipitate under conditions where ferrite would leach satisfactorily. Based on this discovery, a one-step process for the treatment of ferrite was developed. In the plant, the new process almost doubled the recovery of zinc from ferrite in the same equipment as the two-step jarosite process was operated in at that time. In a later expansion of the plant, investment savings were substantial compared to other technologies available. In the solution purification, the key finding was that Co, Ni, and Cu formed specific arsenides in the “hot arsenic zinc dust” step. This was utilized for the development of a three-step purification stage based on fluidized bed technology in all three steps, i.e. removal of Cu, Co and Cd. Both precipitation rates and selectivity increased, which strongly decreased the zinc powder consumption through a substantially suppressed hydrogen gas evolution. Better selectivity improved the value of the precipitates: cadmium, which caused environmental problems in the copper smelter, was reduced from 1-3% reported normally down to 0.05 %, and a cobalt cake with 15 % Co was easily produced in laboratory experiments in the cobalt removal. The zinc powder consumption in the plant for a solution containing Cu, Co, Ni and Cd (1000, 25, 30 and 350 mg/l, respectively), was around 1.8 g/l; i.e. only 1.4 times the stoichiometric demand – or, about 60% saving in powder consumption. Two processes for direct leaching of the concentrate under atmospheric conditions were developed, one of which was implemented in the Kokkola zinc plant. Compared to the existing pressure leach technology, savings were obtained mostly in investment. The scientific basis for the most important processes and process improvements is given in the doctoral thesis. This includes mathematical modeling and thermodynamic evaluation of experimental results and hypotheses developed. Five of the processes developed in this research and development program were implemented in the plant and are still operated. Even though these processes were developed with the focus on the plant in Kokkola, they can also be implemented at low cost in most of the zinc plants globally, and have thus a great significance in the development of the electrolytic zinc process in general.

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The number of electric vehicles grows continuously and the implementation of charging electric vehicles is an important issue for the future. Increasing amount of electric vehicles can cause problems to distribution grid by increasing peak load. Currently charging of electric vehicles is uncontrolled, but as the amount of electric vehicles grows, smart charg-ing (controlled charging) will be one possible solution to handle this situation. In this thesis smart charging of electric vehicles is examined from electricity retailers` point of view. The purpose is to find out plausible saving potentials of smart charging, when it´s controlled by price signal. Saving potential is calculated by comparing costs of price signal controlled charging and uncontrolled charging.