Towards sustainable Iron- and steelmaking with economic optimization

The iron and steelmaking industry is among the major contributors to the anthropogenic emissions of carbon dioxide in the world. The rising levels of CO2 in the atmosphere and the global concern about the greenhouse effect and climate change have brought about considerable investigations on how to reduce the energy intensity and CO2 emissions of this industrial sector. In this thesis the problem is tackled by mathematical modeling and optimization using three different approaches. The possibility to use biomass in the integrated steel plant, particularly as an auxiliary reductant in the blast furnace, is investigated. By pre-processing the biomass its heating value and carbon content can be increased at the same time as the oxygen content is decreased. As the compression strength of the preprocessed biomass is lower than that of coke, it is not suitable for replacing a major part of the coke in the blast furnace burden. Therefore the biomass is assumed to be injected at the tuyere level of the blast furnace. Carbon capture and storage is, nowadays, mostly associated with power plants but it can also be used to reduce the CO2 emissions of an integrated steel plant. In the case of a blast furnace, the effect of CCS can be further increased by recycling the carbon dioxide stripped top gas back into the process. However, this affects the economy of the integrated steel plant, as the amount of top gases available, e.g., for power and heat production is decreased. High quality raw materials are a prerequisite for smooth blast furnace operation. High quality coal is especially needed to produce coke with sufficient properties to ensure proper gas permeability and smooth burden descent. Lower quality coals as well as natural gas, which some countries have in great volumes, can be utilized with various direct and smelting reduction processes. The DRI produced with a direct reduction process can be utilized as a feed material for blast furnace, basic oxygen furnace or electric arc furnace. The liquid hot metal from a smelting reduction process can in turn be used in basic oxygen furnace or electric arc furnace. The unit sizes and investment costs of an alternative ironmaking process are also lower than those of a blast furnace. In this study, the economy of an integrated steel plant is investigated by simulation and optimization. The studied system consists of linearly described unit processes from coke plant to steel making units, with a more detailed thermodynamical model of the blast furnace. The results from the blast furnace operation with biomass injection revealed the importance of proper pre-processing of the raw biomass as the composition of the biomass as well as the heating value and the yield are all affected by the pyrolysis temperature. As for recycling of CO2 stripped blast furnace top gas, substantial reductions in the emission rates are achieved if the stripped CO2 can be stored. However, the optimal recycling degree together with other operation conditions is heavily dependent on the cost structure of CO2 emissions and stripping/storage. The economical feasibility related to the use of DRI in the blast furnace depends on the price ratio between the DRI pellets and the BF pellets. The high amount of energy needed in the rotary hearth furnace to reduce the iron ore leads to increased CO2 emissions.

Reinventing the third way : towards new forms of economic and democratic conduct

Avhandlingen studerar samspelet mellan det politiska och det ekonomiska systemet genom det föregående seklet, med speciellt fokus på den nyliberala omdaning som utspelats de senaste tre årtiondena. Med en liberaliserad ekonomi och en individualiserad människa måste också det politiska systemet utformas på ett annat sätt. Gradvisa förändringar har varit synliga, som den växande nätverksorganiseringen, dvs. att olika typer av utvecklingspolitik allt mer genomförs som ett samspel mellan samhällssektorerna, istället för att enbart utföras av den offentliga sektorn som tidigare. Genom fyra fallstudier i Österbotten demonstreras hur arenor för samverkan kan konstrueras i enlighet med vad den aktuella frågan kräver. Ett exempel är det innovationsnätverk som skapats i Karleby-Jakobstad-regionen, där offentliga och privata intressenter deltar, och som samtidigt bryter traditionella administrativa gränser. Ett annat mer negativt exempel är omstruktureringsprocessen i Kaskö-regionen eft er Metsä-Botnia-fabrikens nedläggning, där småkommunproblemet tillsammans med att den privata intressenten inte haft skyldighet att samverka lett till att en tillräckligt regionalt förankrad arena för en långsiktig utvecklingspolitik inte har kunnat skapas. Det här visar på trögheten i det finska systemet, där en stark enhetsstat och en splittrad kommunal nivå ur ett historiskt perspektiv hindrat flexibla anpassningar till samhällsförändringar. Avhandlingen visar att nätverksorganiseringen bör vara en integrerad del av de representativa strukturerna för att kunna påverka processernas utfall. Avhandlingen visar framförallt att deltagande och funktionellt definierade regionala och lokala arenor har stor potential, både ekonomiskt och demokratiskt. Det handlar om att skapa en kultur med aktiverade och engagerade medborgare, vilket står i kontrast till det allt mer passiverande representativa systemet. ---------------------------------------- Väitöskirja tutkii viime vuosisadan poliittisen ja taloudellisen järjestelmän vuorovaikutusta keskittyen erityisesti kolmen viimeisen vuosikymmenen uusliberaaliseen muutokseen. Talouden liberalisoituminen ja ihmisen individualisoituminen edellyttävät myös poliittisen järjestelmän mukautumista. Asteittaisia muutoksia on ollut havaittavissa, kuten kasvava verkosto-organisaatio, toisin sanoen eri alojen kehityspolitiikkaa toteutetaan yhä enemmän eri yhteiskuntasektoreiden vuorovaikutuksena, kun aikaisemmin ainoastaan julkinen sektori vastasi kehityspolitiikan toteuttamisesta. Pohjanmaan maakunnan neljän tapaustutkimuksen avulla osoitetaan, miten vuorovaikutusareena voidaan rakentaa kulloinkin ajankohtaisen asiakokonaisuuden ympärille. Tästä esimerkkinä on Kokkola-Pietarsaari –alueen innovaatioverkosto, johon osallistuvat sekä julkiset että yksityiset sidosryhmät ja joka samalla rikkoo perinteisiä hallinnollisia rajoja. Toinen, kielteisempi esimerkki on Kaskisten alueen rakennemu utosprosessi Metsä-Botnian tehtaan sulkemisen jälkeen. Siellä pienkuntaongelma yhdistettynä siihen, että yksityinen sidosryhmä ei ole ollut velvollinen tekemään yhteistyötä, on johtanut siihen, että ei ole kyetty luomaan alueen pitkäaikaiseen kehittämiseen sitoutunutta vuorovaikutusareenaa. Tämä osoittaa suomalaisen järjestelmän kankeuden, jossa historiallisesta näkökulmasta vahva yhtenäinen valtio ja hajanainen kuntataso estävät joustavan yhteiskuntamuutoksiin sopeutumisen. Väitöskirja osoittaa, että verkosto-organisaation on oltava yhteiskunnassa vaikuttaviin rakenteisiin integroitu osa, jotta se voi vaikuttaa prosessien tuloksiin. Väitöskirja osoittaa ennen kaikkea, että osallistuvilla ja toiminnallisesti määritellyillä alueellisilla ja paikallisilla areenoilla on suuri taloudellinen ja demokraattinen potentiaali. Passivoivan edustavan järjestelmän tilalle on luotava aktiivisten ja tavoitteisiin sitoutuneiden kansalaisten vuorovaikutusjärjestelmä.

Assessment of techno-economic use cases for small-scale island grids

The main objective of the study was to define the methodology for assessing the limits for application island grids instead of interconnecting with existing grid infrastructure. The model for simulation of grid extension distance and levelised cost of electricity has been developed and validated by the case study in Finland. Thereafter, sensitivities of the application limits were examined with the respect to operational environment, load conditions, supply security and geographical location. Finally, recommendations for the small-scale rural electrification projects in the market economy environment have been proposed.

Deinking sludge utilization possibilities: technical, economic, and environmental assessments

This report introduces the ENPI project called “EMIR - Exploitation of Municipal and Industrial Residues” which was executed in a co-operation between Lappeenranta University of Technology (LUT), Saint Petersburg State University of Economics (SPbSUE), Saint Petersburg State Technical University of Plant Polymers (SPbSTUPP) and industrial partners from both Leningrad Region (LR), Russia and Finland. The main targets of the research were to identify the possibilities for deinking sludge management scenarios in co-operation with partner companies, to compare the sustainability of the alternatives, and to provide recommendations for the companies in the Leningrad Region on how to best manage deinking sludge. During the literature review, 24 deinking sludge utilization possibilities were identified, the majority falling under material recovery. Furthermore, 11 potential utilizers of deinking sludge were found within the search area determined by the transportation cost. Each potential utilizer was directly contacted in order to establish cooperation for deinking sludge utilization. Finally, four companies, namely, “Finnsementti” – a cement plant in Finland (S1), “St.Gobian Weber” – a light-weight aggregate plant in Finland (S2), “LSR-Cement” – a cement plant in LR (S3), and “Rockwool” – a stone wool plant in LR (S4) were seen as the most promising partners and were included in the economic and environmental assessments. Economic assessment using cost-benefit analysis (CBA) indicated that substitution of heavy fuel oil with dry deinking sludge in S2 was the most feasible option with a benefit/cost ratio (BCR) of 3.6 when all the sludge was utilized. At the same time, the use of 15% of the total sludge amount (the amount that could potentially be treated in the scenario) resulted in a BCR of only 0.16. The use of dry deinking sludge in the production of cement (S3) is a slightly more feasible option with a BCR of 1.1. The use of sludge in stone wool production is feasible only when all the deinking sludge is used and burned in an existing incineration plant. The least economically feasible utilization possibility is the use of sludge in cement production in Finland (S1) due to the high gate fee charged. Environmental assessment was performed applying internationally recognized life cycle assessment (LCA) methodologies: ISO 14040 and ISO 14044. The results of a consequential LCA stated that only S1 and S2 lead to a reduction of all environmental impacts within the impact categories chosen compared to the baseline scenario where deinking sludge is landfilled. Considering S1, the largest reduction of 13% was achieved for the global warming potential (GWP), whereas for S2, the largest decrease of abiotic depletion potential (ADP) was by 1.7%, the eutrophication potential (EP) by 1.8%, and a GWP of 2.1% was documented. In S3, the most notable increase of ADP and acidification potential (AP) by 2.6 and 1.5% was indicated, while the GWP was reduced by 12%, the largest out of all the impact categories. In S4, ADP and AP increased by 2.3 and 2.1% respectively, whereas ODP was reduced by 25%. During LCA, it was noticed that substitution of fuels causes a greater reduction of environmental impact (S1 and S2) than substitution of raw materials (S3 and S4). Despite a number of economically and environmentally acceptable deinking sludge utilization methods being assessed in the research, evaluation of bottlenecks and communications with companies’ representatives uncovered the fact that the availability of the raw materials consumed, and the risks associated with technological problems resulting from the sludge utilization, limited the willingness of industrial partners to start deinking sludge utilization. The research results are of high value for decision-makers at already existing paper mills since the result provide insights regarding alternatives to the deinking sludge utilization possibilities already applied. Thus, the research results support the maximum economic and environmental value recovery from waste paper utilization.

Economic Burden of Psoriasis

Psoriasis may cause a substantial economic burden to patients, health service providers, third parties, and the society as a whole. However, all of these costs may not be adequately considered when assessing the treatment costs for psoriasis. Psoriasis may negatively affect work productivity as psoriasis has a relatively high incidence in working age people that lead to possible costs because of lost productivity. The aims of this thesis were to estimate the economic burden of psoriasis particularly from patients’ and health service providers’ perspectives and to estimate the background factors (e.g., severity of psoriasis) that may have led to high costs. Another aim was to estimate the total medication costs and to estimate psoriasis’ proportion of health-related productivity losses. The patient sample was based on patients with psoriasis who visited the Department of Dermatology in Turku University Hospital during a one-year study period. These patients were sent a questionnaire. From the patients who gave consent, medication information, clinical information, and number of visits to Turku University Hospital were collected. This data was linked to the information from the questionnaire. Overall psoriasis was estimated to cause a substantial economic burden for the patient, health service provider, health insurance system, employer, and the society as a whole. The direct costs represented only a small proportion of the overall financial burden of psoriasis, whereas indirect costs were significant. The estimated annual costs for patients and employers were almost twice the costs to health service providers or the Social Insurance Institution of Finland. In conclusion, the cost contribution of patients and employers should be considered when assessing the costs of different treatments, in addition to commonly studied direct costs of medications and costs to health service providers. Methods used to assess these costs should be well justified and be described clearly to allow comparisons between studies and to evaluate the quality of the results.