260 resultados para procurement process


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Environmental issues, including global warming, have been serious challenges realized worldwide, and they have become particularly important for the iron and steel manufacturers during the last decades. Many sites has been shut down in developed countries due to environmental regulation and pollution prevention while a large number of production plants have been established in developing countries which has changed the economy of this business. Sustainable development is a concept, which today affects economic growth, environmental protection, and social progress in setting up the basis for future ecosystem. A sustainable headway may attempt to preserve natural resources, recycle and reuse materials, prevent pollution, enhance yield and increase profitability. To achieve these objectives numerous alternatives should be examined in the sustainable process design. Conventional engineering work cannot address all of these substitutes effectively and efficiently to find an optimal route of processing. A systematic framework is needed as a tool to guide designers to make decisions based on overall concepts of the system, identifying the key bottlenecks and opportunities, which lead to an optimal design and operation of the systems. Since the 1980s, researchers have made big efforts to develop tools for what today is referred to as Process Integration. Advanced mathematics has been used in simulation models to evaluate various available alternatives considering physical, economic and environmental constraints. Improvements on feed material and operation, competitive energy market, environmental restrictions and the role of Nordic steelworks as energy supplier (electricity and district heat) make a great motivation behind integration among industries toward more sustainable operation, which could increase the overall energy efficiency and decrease environmental impacts. In this study, through different steps a model is developed for primary steelmaking, with the Finnish steel sector as a reference, to evaluate future operation concepts of a steelmaking site regarding sustainability. The research started by potential study on increasing energy efficiency and carbon dioxide reduction due to integration of steelworks with chemical plants for possible utilization of available off-gases in the system as chemical products. These off-gases from blast furnace, basic oxygen furnace and coke oven furnace are mainly contained of carbon monoxide, carbon dioxide, hydrogen, nitrogen and partially methane (in coke oven gas) and have proportionally low heating value but are currently used as fuel within these industries. Nonlinear optimization technique is used to assess integration with methanol plant under novel blast furnace technologies and (partially) substitution of coal with other reducing agents and fuels such as heavy oil, natural gas and biomass in the system. Technical aspect of integration and its effect on blast furnace operation regardless of capital expenditure of new operational units are studied to evaluate feasibility of the idea behind the research. Later on the concept of polygeneration system added and a superstructure generated with alternative routes for off-gases pretreatment and further utilization on a polygeneration system producing electricity, district heat and methanol. (Vacuum) pressure swing adsorption, membrane technology and chemical absorption for gas separation; partial oxidation, carbon dioxide and steam methane reforming for methane gasification; gas and liquid phase methanol synthesis are the main alternative process units considered in the superstructure. Due to high degree of integration in process synthesis, and optimization techniques, equation oriented modeling is chosen as an alternative and effective strategy to previous sequential modelling for process analysis to investigate suggested superstructure. A mixed integer nonlinear programming is developed to study behavior of the integrated system under different economic and environmental scenarios. Net present value and specific carbon dioxide emission is taken to compare economic and environmental aspects of integrated system respectively for different fuel systems, alternative blast furnace reductants, implementation of new blast furnace technologies, and carbon dioxide emission penalties. Sensitivity analysis, carbon distribution and the effect of external seasonal energy demand is investigated with different optimization techniques. This tool can provide useful information concerning techno-environmental and economic aspects for decision-making and estimate optimal operational condition of current and future primary steelmaking under alternative scenarios. The results of the work have demonstrated that it is possible in the future to develop steelmaking towards more sustainable operation.

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Kuudenarvoista kromia käytetään natriumkloraatin valmistuksessa prosessin tuotantotehokkuuden ja turvallisuuden parantamiseksi. Kromia kuitenkin poistuu prosessista muutamaa reittiä pitkin. Koska kuuudenarvoisella kromilla on syöpää aiheuttavia, mutageenisiä sekä lisääntymiselle myrkyllisiä ominaisuuksia, olisi tärkeää ymmärtää, miten kromi kulkeutuu prosessin eri osiin, ja kuinka paljon sitä poistuu prosessista. Tämä on tärkeää, jotta osataan hallita kromin käytöstä aiheutuvat riskit, sekä toisaalta myös tehostaa kromin käyttöä prosessissa. Työn tarkoituksena oli tuottaa tietoa kromin käytöstä natriumkloraattiprosessissa. Työssä tutkittiin kromitasetta prosessin keskeisimmissä yksikköoperaatioissa. Myös kromin saostumista katodien pinnalle arvioitiin määrällisesti. Eri prosessinäytteistä tutkittiin lisäksi kromin hapetusasteita. Edellä mainittuja tutkimuskohteita varten määritettiin prosessinäytteiden kromipitoisuus. Eri prosessioperaatioille suoritettiin lisäksi taselaskelmat. Työn tuloksena esitettiin kromitase sekä yksikköoperaatioille että koko prosessille. Erinäisten epätarkkuustekijöiden vuoksi tasetta ei kuitenkaan pystytty määrittämään halutulla tarkkuudella, ja siksi työssä esitettyä tasetta voidaan pitää vain suuntaa antavana laskelmana. Katodien pinnalle saostunutta kromin määrää pidettiin kuitenkin oikean suuruusluokan tuloksena. Prosessinäytteiden hapetusasteita ei voitu arvioida, sillä saadut kokonaiskromitulokset eivät olleet täysin luotettavia. Huolimatta tulosten epätarkkuudesta, työ tuotti tärkeää tietoa prosessin toiminnasta kromin suhteen. Työtä voidaan hyödyntää jatkossa monin tavoin prosessin kromitaseen seurannassa.

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Tutkielmassa rakennettiin laskentamalli metsäteollisuuden puunhankinnan hankintalähteen kannattavuuden määrittämiseksi ja selittämiseksi. Tutkimuksessa noudatettiin konstruktiivisen tapaustutkimuksen tutkimusotetta. Tutkimuksen kohdeorganisaationa oli kansainvälisesti toimivan metsäteollisuusyrityksen Suomen puunhankintaorganisaatio. Kannattavuusmalli määrittelee hankintalähteen kannattavuuden sekä käsitteellisellä että laskentamenettelyn tasolla. Kannattavuusmallin katesuure on porttikate, joka rakennettiin taloudellisen lisäarvon teoriaan nojaten kohdeorganisaation tarpeiden ja sen laskenta-asiantuntijoiden näkemysten perusteella. Kannattavuusmallin rakenne ja osat kuvattiin seikkaperäisesti. Kannattavuusmallin käyttämän liiketoimintadatan poiminta ja laskentasuureiden raportointi testattiin. Mallin tarvitsemat laskentatiedot on saatavissa kohdeorganisaation kehitteillä olevasta toiminnanohjausjärjestelmästä. Laskentamallin hyödyntämismahdollisuudet arvioitiin. Hankintalähteen kannattavuutta mittaavalla porttikatteella voidaan ohjata puunhankintaorganisaatiota sen tavoitteiden saavuttamisessa. Malli ilmaisee porttikatteeseen vaikuttavien tekijöiden vaikutuksen kannattavuuteen, minkä avulla voidaan tehdä parempia päätöksiä hankintalähteiden hyödyntämisessä. Aiemmista tutkimuksista poiketen malli huomioi hankintalähteen suoritteen arvon tärkeimmille asiakastehtaille perustuen todellisiin liiketapahtumiin. Kannattavuusmallia voidaan hyödyntää laajalti metsäteollisuusyritysten tavaralajimenetelmään perustuvassa puunhankinnassa. Kannattavuusmallin rakentaminen rohkaisee puunhankinnan johtoa ja laskentahenkilöitä hedelmällisen yhteistyöhön.

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Over the past decades, companies’ interest in controlling indirect sourcing process has increased. New indirect procurement strategies developed for the companies are needed in order to manage their indirect costs. New cost management strategies allow companies to improve their core competences. The research methodology and used in this thesis is qualitative. The theory is based on scientific publications. Empirical data given by the case organization, and was collected in the company’s own systems and in project steering meetings. The purpose of the study was to select a new electronic system for the company and give options for the company to reduce case organization’s indirect costs. The result showed that the most effective indirect cost management strategy was adopting a new electronic procurement system.

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The main objective of the study was to form a strategic process model and project management tool to help IFRS change implementation projects in the future. These research results were designed based on the theoretical framework of Total Quality Management and leaning on the facts that were collected during the empirical case study of IAS 17 change. The us-age of the process oriented approach in IFRS standard change implementation after the initial IFRS implementation is rationalized with the following arguments: 1) well designed process tools lead to optimization of resources 2) With the help of process stages and related tasks it is easy to ensure the efficient way of working and managing the project as well as make sure to include all necessary stakeholders to the change process. This research is following the qualitative approach and the analysis is in describing format. The first part of the study is a literature review and the latter part has been conducted as a case study. The data has been col-lected in the case company with interviews and observation. The main findings are a process model for IFRS standard change process and a check-list formatted management tool for up-coming IFRS standard change projects. The process flow follows the main cornerstones in IASB’s standard setting process and the management tool has been divided to stages accordingly.