Production of Mg(OH)2 from Mg-silicate rock for CO2 mineral sequestration

Sequestration of carbon dioxide in mineral rocks, also known as CO2 Capture and Mineralization (CCM), is considered to have a huge potential in stabilizing anthropogenic CO2 emissions. One of the CCM routes is the ex situ indirect gas/sold carbonation of reactive materials, such as Mg(OH)2, produced from abundantly available Mg-silicate rocks. The gas/solid carbonation method is intensively researched at Åbo Akademi University (ÅAU ), Finland because it is energetically attractive and utilizes the exothermic chemistry of Mg(OH)2 carbonation. In this thesis, a method for producing Mg(OH)2 from Mg-silicate rocks for CCM was investigated, and the process efficiency, energy and environmental impact assessed. The Mg(OH)2 process studied here was first proposed in 2008 in a Master’s Thesis by the author. At that time the process was applied to only one Mg-silicate rock (Finnish serpentinite from the Hitura nickel mine site of Finn Nickel) and the optimum process conversions, energy and environmental performance were not known. Producing Mg(OH)2 from Mg-silicate rocks involves a two-staged process of Mg extraction and Mg(OH)2 precipitation. The first stage extracts Mg and other cations by reacting pulverized serpentinite or olivine rocks with ammonium sulfate (AS) salt at 400 - 550 oC (preferably < 450 oC). In the second stage, ammonia solution reacts with the cations (extracted from the first stage after they are leached in water) to form mainly FeOOH, high purity Mg(OH)2 and aqueous (dissolved) AS. The Mg(OH)2 process described here is closed loop in nature; gaseous ammonia and water vapour are produced from the extraction stage, recovered and used as reagent for the precipitation stage. The AS reagent is thereafter recovered after the precipitation stage. The Mg extraction stage, being the conversion-determining and the most energy-intensive step of the entire CCM process chain, received a prominent attention in this study. The extraction behavior and reactivity of different rocks types (serpentinite and olivine rocks) from different locations worldwide (Australia, Finland, Lithuania, Norway and Portugal) was tested. Also, parametric evaluation was carried out to determine the optimal reaction temperature, time and chemical reagent (AS). Effects of reactor types and configuration, mixing and scale-up possibilities were also studied. The Mg(OH)2 produced can be used to convert CO2 to thermodynamically stable and environmentally benign magnesium carbonate. Therefore, the process energy and life cycle environmental performance of the ÅAU CCM technique that first produces Mg(OH)2 and the carbonates in a pressurized fluidized bed (FB) were assessed. The life cycle energy and environmental assessment approach applied in this thesis is motivated by the fact that the CCM technology should in itself offer a solution to what is both an energy and environmental problem. Results obtained in this study show that different Mg-silicate rocks react differently; olivine rocks being far less reactive than serpentinite rocks. In summary, the reactivity of Mg-silicate rocks is a function of both the chemical and physical properties of rocks. Reaction temperature and time remain important parameters to consider in process design and operation. Heat transfer properties of the reactor determine the temperature at which maximum Mg extraction is obtained. Also, an increase in reaction temperature leads to an increase in the extent of extraction, reaching a maximum yield at different temperatures depending on the reaction time. Process energy requirement for producing Mg(OH)2 from a hypothetical case of an iron-free serpentine rock is 3.62 GJ/t-CO2. This value can increase by 16 - 68% depending on the type of iron compound (FeO, Fe2O3 or Fe3O4) in the mineral. This suggests that the benefit from the potential use of FeOOH as an iron ore feedstock in iron and steelmaking should be determined by considering the energy, cost and emissions associated with the FeOOH by-product. AS recovery through crystallization is the second most energy intensive unit operation after the extraction reaction. However, the choice of mechanical vapor recompression (MVR) over the “simple evaporation” crystallization method has a potential energy savings of 15.2 GJ/t-CO2 (84 % savings). Integrating the Mg(OH)2 production method and the gas/solid carbonation process could provide up to an 25% energy offset to the CCM process energy requirements. Life cycle inventory assessment (LCIA) results show that for every ton of CO2 mineralized, the ÅAU CCM process avoids 430 - 480 kg CO2. The Mg(OH)2 process studied in this thesis has many promising features. Even at the current high energy and environmental burden, producing Mg(OH)2 from Mg-silicates can play a significant role in advancing CCM processes. However, dedicated future research and development (R&D) have potential to significantly improve the Mg(OH)2 process performance.

Hitsatun rakenteen lujuustarkastelu kokeellisesti määritetyn kuormitushistorian perusteella

Työssä tutkittiin jätteen murskauksesta murskaimeen aiheutuvia kuormituksia vastusvenymäliuskamittauksilla. Eri jätetyyppien aiheuttamia kuormituksia tutkittiin erillisinä tapauksina ja näistä tyyppikuormituksista johdettiin rakenteen normaalia käyttöä vastaava kuormitushistoria käyttäen painokertoimia eri tyyppikuormien kesken. Murskaimen runkorakennetta tutkittiin FE-analyysillä käyttäen kuormituksena kenttämittauksilla saatua todellista kuormitusta. FE-menetelmällä tutkittiin väsymisen kannalta kriittisiä kohtia rakenteesta. Tulosten perusteella kriittisiin yksityiskohtiin laadittiin parannusehdotuksia, joiden perusteella yhteistyössä työn teettäjän kanssa laadittiin uudet rakenneratkaisut. Rakenteen kestoikä määritettiin väsymisvaurion kannalta kriittisimmän yksityiskohdan mukaan. Kestoiän määrittämiseen käytettiin Palmgren-Miner menetelmää ja Palmgren-Miner menetelmästä johdettua ekvivalentin jännitysvaihtelun menetelmää. Muutosten jälkeen rakenne täyttää sille asetetun suunnittelukestoiän käytettyjen menetelmien perusteella.

Characterisation of Laser Beam and Paper Material Interaction

It is known already from 1970´s that laser beam is suitable for processing paper materials. In this thesis, term paper materials mean all wood-fibre based materials, like dried pulp, copy paper, newspaper, cardboard, corrugated board, tissue paper etc. Accordingly, laser processing in this thesis means all laser treatments resulting material removal, like cutting, partial cutting, marking, creasing, perforation etc. that can be used to process paper materials. Laser technology provides many advantages for processing of paper materials: non-contact method, freedom of processing geometry, reliable technology for non-stop production etc. Especially packaging industry is very promising area for laser processing applications. However, there are only few industrial laser processing applications worldwide even in beginning of 2010´s. One reason for small-scale use of lasers in paper material manufacturing is that there is a shortage of published research and scientific articles. Another problem, restraining the use of laser for processing of paper materials, is colouration of paper material i.e. the yellowish and/or greyish colour of cut edge appearing during cutting or after cutting. These are the main reasons for selecting the topic of this thesis to concern characterization of interaction of laser beam and paper materials. This study was carried out in Laboratory of Laser Processing at Lappeenranta University of Technology (Finland). Laser equipment used in this study was TRUMPF TLF 2700 carbon dioxide laser that produces a beam with wavelength of 10.6 μm with power range of 190-2500 W (laser power on work piece). Study of laser beam and paper material interaction was carried out by treating dried kraft pulp (grammage of 67 g m-2) with different laser power levels, focal plane postion settings and interaction times. Interaction between laser beam and dried kraft pulp was detected with different monitoring devices, i.e. spectrometer, pyrometer and active illumination imaging system. This way it was possible to create an input and output parameter diagram and to study the effects of input and output parameters in this thesis. When interaction phenomena are understood also process development can be carried out and even new innovations developed. Fulfilling the lack of information on interaction phenomena can assist in the way of lasers for wider use of technology in paper making and converting industry. It was concluded in this thesis that interaction of laser beam and paper material has two mechanisms that are dependent on focal plane position range. Assumed interaction mechanism B appears in range of average focal plane position of 3.4 mm and 2.4 mm and assumed interaction mechanism A in range of average focal plane position of 0.4 mm and -0.6 mm both in used experimental set up. Focal plane position 1.4 mm represents midzone of these two mechanisms. Holes during laser beam and paper material interaction are formed gradually: first small hole is formed to interaction area in the centre of laser beam cross-section and after that, as function of interaction time, hole expands, until interaction between laser beam and dried kraft pulp is ended. By the image analysis it can be seen that in beginning of laser beam and dried kraft pulp material interaction small holes off very good quality are formed. It is obvious that black colour and heat affected zone appear as function of interaction time. This reveals that there still are different interaction phases within interaction mechanisms A and B. These interaction phases appear as function of time and also as function of peak intensity of laser beam. Limit peak intensity is the value that divides interaction mechanism A and B from one-phase interaction into dual-phase interaction. So all peak intensity values under limit peak intensity belong to MAOM (interaction mechanism A one-phase mode) or to MBOM (interaction mechanism B onephase mode) and values over that belong to MADM (interaction mechanism A dual-phase mode) or to MBDM (interaction mechanism B dual-phase mode). Decomposition process of cellulose is evolution of hydrocarbons when temperature is between 380- 500°C. This means that long cellulose molecule is split into smaller volatile hydrocarbons in this temperature range. As temperature increases, decomposition process of cellulose molecule changes. In range of 700-900°C, cellulose molecule is mainly decomposed into H2 gas; this is why this range is called evolution of hydrogen. Interaction in this range starts (as in range of MAOM and MBOM), when a small good quality hole is formed. This is due to “direct evaporation” of pulp via decomposition process of evolution of hydrogen. And this can be seen can be seen in spectrometer as high intensity peak of yellow light (in range of 588-589 nm) which refers to temperature of ~1750ºC. Pyrometer does not detect this high intensity peak since it is not able to detect physical phase change from solid kraft pulp to gaseous compounds. As interaction time between laser beam and dried kraft pulp continues, hypothesis is that three auto ignition processes occurs. Auto ignition of substance is the lowest temperature in which it will spontaneously ignite in a normal atmosphere without an external source of ignition, such as a flame or spark. Three auto ignition processes appears in range of MADM and MBDM, namely: 1. temperature of auto ignition of hydrogen atom (H2) is 500ºC, 2. temperature of auto ignition of carbon monoxide molecule (CO) is 609ºC and 3. temperature of auto ignition of carbon atom (C) is 700ºC. These three auto ignition processes leads to formation of plasma plume which has strong emission of radiation in range of visible light. Formation of this plasma plume can be seen as increase of intensity in wavelength range of ~475-652 nm. Pyrometer shows maximum temperature just after this ignition. This plasma plume is assumed to scatter laser beam so that it interacts with larger area of dried kraft pulp than what is actual area of beam cross-section. This assumed scattering reduces also peak intensity. So result shows that assumably scattered light with low peak intensity is interacting with large area of hole edges and due to low peak intensity this interaction happens in low temperature. So interaction between laser beam and dried kraft pulp turns from evolution of hydrogen to evolution of hydrocarbons. This leads to black colour of hole edges.

Etelä-Karjalan alueen yritysten jätevirrat ja jätteenkäsittelyn kannattavuus alueella

Diplomityön tavoitteena oli selvittää Etelä-Karjalan alueen yritysten jätevirtoja ja sekalaisen rakennusjätteen koostumusta. Jätevirtojen selvityksessä keskityttiin metsäteollisuuden, rakennusteollisuuden ja kaupan alan jätevirtoihin. Tarkoituksena oli selvittää mahdollisessa jätteenkäsittelylaitoksessa hyödynnettävien jätejakeiden määrät. Selvitettyjen tietojen perusteella arvioitiin erilaisten jätteenkäsittelyvaihtoehtojen kannattavuutta yritysnäkökul-masta Etelä-Karjalan alueella. Rakennusjätteen koostumusta tutkittiin lajittelemalla ja pun-nitsemalla sekalaisia rakennusjätekuormia jätejakeittain. Etelä-Karjalan alueen jätevirtoja selvitettiin muun muassa yrityshaastatteluin ja hyödyntämällä Lassila & Tikanoja Oyj:n tietokantaa. Sekalaisen rakennusjätteen lajittelututkimuksessa selvisi, että sekalaisissa rakennusjäte-kuormissa on lähes 50 m-% hyödynnettävissä olevia jätejakeita. Energiajaetta kuormissa oli yhteensä noin 34 m-% ja kaatopaikkajätettä noin 52 m-%. Kaupan alalta syntyy pää-sääntöisesti paljon pakkausmateriaaleista koostuvaa energiajaetta, kun taas metsäteollisuu-desta syntyy paljon erilaisia prosessijätteitä, joita ei voida hyödyntää työssä tutkituilla me-netelmillä. Lappeenrannan ja Imatran alueilla arvioidaan syntyvän energiajaetta metsäteol-lisuudesta, kaupan alalta ja rakennusteollisuudesta yhteensä noin 4 300 t, puujätettä noin 5 000 t ja sekalaista rakennusjätettä noin 11 700 t. Metsäteollisuuden, rakennusteollisuuden ja kaupan alan jätevirrat Etelä-Karjalassa eivät ole riittävät taloudellisesti kannattavan jätteenkäsittelylaitoksen perustamiseksi. Arvioinnissa huomioitiin laitoksen investointikustannukset sekä muut aiheutuvat kustannukset. Energiajakeen siirtokuormausasema todettiin kannattavaksi tilanteessa, jossa energiajae toimitettaisiin Etelä-Karjalan sijasta Lahteen tai Kouvolaan.

Thermal radiation in combustion systems

A numerical procedure for solving the nongray radiative transfer equation (RTE) in two-dimensional cylindrical participating media is presented. Nongray effects are treated by using a narrow-band approach. Radiative emission from CO, CO2, H2O, CH4 and soot is considered. The solution procedure is applied to study radiative heat transfer in a premixed CH4-O2, laminar, flame. Temperature, soot and IR-active species molar fraction distributions are allowed to vary in the axial direction of the flame. From the obtained results it is possible to quantify the radiative loss in the flame, as well as the importance of soot radiation as compared to gaseous radiation. Since the solution procedure is developed for a two-dimensional cylindrical geometry, it can be applied to other combustion systems such as furnaces, internal combustion engines, liquid and solid propellant combustion.

Hydrometallurgical recovery of valuable metals from secondary raw materials

Wastes and side streams in the mining industry and different anthropogenic wastes often contain valuable metals in such concentrations their recovery may be economically viable. These raw materials are collectively called secondary raw materials. The recovery of metals from these materials is also environmentally favorable, since many of the metals, for example heavy metals, are hazardous to the environment. This has been noticed in legislative bodies, and strict regulations for handling both mining and anthropogenic wastes have been developed, mainly in the last decade. In the mining and metallurgy industry, important secondary raw materials include, for example, steelmaking dusts (recoverable metals e.g. Zn and Mo), zinc plant residues (Ag, Au, Ga, Ge, In) and waste slurry from Bayer process alumina production (Ga, REE, Ti, V). From anthropogenic wastes, waste electrical and electronic equipment (WEEE), among them LCD screens and fluorescent lamps, are clearly the most important from a metals recovery point of view. Metals that are commonly recovered from WEEE include, for example, Ag, Au, Cu, Pd and Pt. In LCD screens indium, and in fluorescent lamps, REEs, are possible target metals. Hydrometallurgical processing routes are highly suitable for the treatment of complex and/or low grade raw materials, as secondary raw materials often are. These solid or liquid raw materials often contain large amounts of base metals, for example. Thus, in order to recover valuable metals, with small concentrations, highly selective separation methods, such as hydrometallurgical routes, are needed. In addition, hydrometallurgical processes are also seen as more environmental friendly, and they have lower energy consumption, when compared to pyrometallurgical processes. In this thesis, solvent extraction and ion exchange are the most important hydrometallurgical separation methods studied. Solvent extraction is a mainstream unit operation in the metallurgical industry for all kinds of metals, but for ion exchange, practical applications are not as widespread. However, ion exchange is known to be particularly suitable for dilute feed solutions and complex separation tasks, which makes it a viable option, especially for processing secondary raw materials. Recovering valuable metals was studied with five different raw materials, which included liquid and solid side streams from metallurgical industries and WEEE. Recovery of high purity (99.7%) In, from LCD screens, was achieved by leaching with H2SO4, extracting In and Sn to D2EHPA, and selectively stripping In to HCl. In was also concentrated in the solvent extraction stage from 44 mg/L to 6.5 g/L. Ge was recovered as a side product from two different base metal process liquors with Nmethylglucamine functional chelating ion exchange resin (IRA-743). Based on equilibrium and dynamic modeling, a mechanism for this moderately complex adsorption process was suggested. Eu and Y were leached with high yields (91 and 83%) by 2 M H2SO4 from a fluorescent lamp precipitate of waste treatment plant. The waste also contained significant amounts of other REEs such as Gd and Tb, but these were not leached with common mineral acids in ambient conditions. Zn was selectively leached over Fe from steelmaking dusts with a controlled acidic leaching method, in which the pH did not go below, but was held close as possible to, 3. Mo was also present in the other studied dust, and was leached with pure water more effectively than with the acidic methods. Good yield and selectivity in the solvent extraction of Zn was achieved by D2EHPA. However, Fe needs to be eliminated in advance, either by the controlled leaching method or, for example, by precipitation. 100% Pure Mo/Cr product was achieved with quaternary ammonium salt (Aliquat 336) directly from the water leachate, without pH adjustment (pH 13.7). A Mo/Cr mixture was also obtained from H2SO4 leachates with hydroxyoxime LIX 84-I and trioctylamine (TOA), but the purities were 70% at most. However with Aliquat 336, again an over 99% pure mixture was obtained. High selectivity for Mo over Cr was not achieved with any of the studied reagents. Ag-NaCl solution was purified from divalent impurity metals by aminomethylphosphonium functional Lewatit TP-260 ion exchange resin. A novel preconditioning method, named controlled partial neutralization, with conjugate bases of weak organic acids, was used to control the pH in the column to avoid capacity losses or precipitations. Counter-current SMB was shown to be a better process configuration than either batch column operation or the cross-current operation conventionally used in the metallurgical industry. The raw materials used in this thesis were also evaluated from an economic point of view, and the precipitate from a waste fluorescent lamp treatment process was clearly shown to be the most promising.

Mineraalisen rakennusjätteen hyötykäyttö maarakentamisessa

Työn tavoitteena on osoittaa betonimurskeen ympäristökelpoisuus maarakennuskäytössä sekä vertailla betonimurskeen ja luonnonmateriaalien elinkaaren aikaisia ympäristövaikutuksia maarakentamisessa. Teoriaosassa käsitellään betonimurskeen maarakennuskäyttöön vaikuttavaa lainsäädäntöä ja sen mahdollisia ympäristövaikutuksia. Lisäksi käydään läpi neitseellisten maarakennusmate-riaalien otosta aiheutuvia ympäristövaikutuksia. Työn kokeellinen osa koostuu kahdesta osasta: materiaalien haitallisten aineiden liukoisuuden mää-rityksistä ja elinkaariarvioinnista. Liukoisuuden määritykset tehtiin kenttäkokeina luonnonolosuhteissa Lahden tiede- ja yrityspuisto Oy:n Jokimaan pilot-luokan maaperätutkimuskeskuksessa. Lisäksi liukoisuudet määritettiin laboratoriossa valtioneuvoston asetuksen eräiden jätteiden hyödyntämisestä maarakentamisessa vaatimusten mukaisesti. Elinkaariarvioinnissa vertailtiin betonimursketta neitseellisiin maarakennusmateriaaleihin skenaarioissa, jotka sisälsivät materiaalin valmistuksen ja kuljetuksen käyttökohteeseen. Neitseellisiä materiaaleja käytettäessä oletettiin, että betoni loppusijoitetaan kaatopaikalle. Elinkaariarvioinnissa käytettiin Gabi-elinkaarimallinnusohjelmaa ja skenaarioita vertailtiin hiilidioksidiekvivalenttipäästöihin. Lisäksi elinkaariarviointiin otettiin mukaan vielä kehitysvaiheessa oleva menetelmä maankäytön indikaattoreiden määrittämiseen. Menetelmällä tutkittiin soranoton vaikutusta soraharjun maaperän laadulle ennen ja jälkeen soranoton. Tulokseksi liukoisuuden määrityksistä saatiin, että betonimurskekerroksen läpi suotautuneen sade-veden pH nousee hyvin emäksiseksi. pH:n nousu vaikuttaisi korreloivan positiivisesti tiettyjen metallien liukoisuuteen. Huomattavaa on, että kenttäkokeiden liukoisuudet ja laboratoriossa määritetyt liukoisuudet poikkesivat joltain osin toisistaan. Elinkaaritarkastelussa hiilidioksidiekvivalentti päästöjen suhteen suurin päästö aiheutuu, jos betoni loppusijoitetaan kaatopaikalle hyötykäytön sijaan. Maaperän laadun muutoksien määrittämisen menetelmä ei vielä ole käyttökelpoinen lähtötietojen yksinkertaistuksien ja puutteiden takia. Betonimurskeen hyötykäyttö maarakentamisessa ei aiheuta merkittäviä ympäristövaikutuksia, kun altistus vedelle minimoidaan. Lisäksi hyötykäyttö on suositeltava vaihtoehto loppusijoitukselle kaatopaikan rakentamisen ja käytön aiheuttamien ympäristövaikutusten takia.

Effects of different ammoniacal nitrogen sources on N-metabolism of the atmospheric bromeliad Tillandsia pohliana Mez

Increasing levels of atmospheric ammonia from anthropogenic sources have become a serious problem for natural vegetation. Short-term effects of different ammoniacal sources on the N metabolism of Tillandsia pohliana, an atmospheric bromeliad, were investigated. One-year-old, aseptically grown plants were transferred to a modified Knudson medium lacking N for three weeks. Plants were subsequently transferred to Knudson media supplemented with 0.5, 1.0, or 1.5 mM of N in the forms of NH3 or NH4+ as the sole N source. The activities of glutamine synthetase (GS) and glutamate dehydrogenase (GDH-NADH) were determined after 40 h. The GS activity was stimulated significantly by increasing the levels of the gaseous form. The GDH-NADH activity increased significantly under increasing N concentrations with NH3, while no significant differences were observed with NH4+ as a N source. These results may reflect a faster NH3 absorption by T. pohliana compared to NH4+ uptake. The increased activity of GDH-NADH in NH3 treatment may play a role in protecting the cells from the toxic effects of increased endogenous level of free ammonium. A raise in the concentration of N, especially in the form of NH3, greatly increased the content of free amino acids and soluble proteins. A possible utilisation of T. pohliana to evaluate the changes of atmospheric gaseous ammonia is proposed.

Myyntiprosessin kehittäminen logistiikkapalveluyrityksessä

Tämä diplomityö on toteutettu HUB logistics Oy:lle ja se keskittyy yrityksen myyntiprosessin kehittämiseen. Tutkimuksen tavoitteena on selvittää millaisilla myynnin johtamisen keinoilla ja myyntiprosessin vaiheilla voidaan tehokkaasti toteuttaa yrityksen myyntiä. Tutkimus keskittyy myynnin suunnitteluun, tavoit- teiden asettamiseen ja niiden mittaamiseen sekä seurantaan. Tutkimuksessa huomioidaan myyntiorganisaation rakenne sekä myyntiprosessin eri vaiheet. Näiden näkökulmien lisäksi tärkeänä teemana on myös lean-ajattelun hyödyn- täminen myyntiprosessin kehittämisessä. Kohdeyrityksestä on kerätty tietoa toteuttamalla haastatteluita myyntiorganisaatiossa mukana oleville henkilöille. Tutkimuksen tuloksena saatiin, että myyntiprosessin toiminnalla ja tehokkuu- della on merkittävä rooli koko yrityksen toiminnan kannalta. Myynnin käytän- nön tekeminen on sidottu vahvasti yrityksen strategisiin tavoitteisiin ja niiden tulokset vaikuttavat tavoitteiden onnistumiseen. Myyntiprosessi on raskas ja vaatii usein paljon resursseja. Resurssien tehokkaalla käytöllä ja prosessin vai- heita parantamalla voidaan saavuttaa mittavia säästöjä. Toisaalta vähintään yhtä tärkeää on ymmärtää myyntiprosessin sisältämät hukat. Niiden poistamisella ja keskittymisellä asiakkaalle luotavaan arvoon saadaan jatkuvan kehittämisen kautta yhä sujuvampi ja tehokkaampi myyntiprosessi yrityksen käyttöön.

Jätteen kaasutus ja energiakäyttö

Kiinteiden polttoaineiden muuntaminen kaasumaiseen muotoon eli kaasuttaminen herätti jo vuosia sitten tutkijoiden kiinnostusta. Suomessa yleinen mielenkiinto on viimeaikoina keskittynyt edullisempien polttoaineiden kaasuttamiseen ja saatavan tuotekaasun polttamiseen. Lahti Energian uudessa Kymijärvi 2 voimalaitoksessa kaasutetaan puuta ja kierrätyspolttoainetta (REF). Saatava tuotekaasu jäähdytetään ja suodatetaan, jotta epäpuhtaudet saadaan pois tuotekaasusta. Puhdistettu tuotekaasu poltetaan kaasukattilassa korkeilla höyrynarvoilla. Tuotekaasun jäähdyttämistä ei ole paljoa tehty eikä siitä ole juurikaan tieteellistä tutkimusta eikä kokemusta. Tuotekaasun jäähtyessä partikkelit tarttuvat lämpöpinnoille aiheuttaen kerrostumia. Kerrostumat heikentävät lämmönsiirtoa olennaisesti. Tämän työn tarkoitus on tutkia kaasutusprosessia, tuotekaasun jäähdyttimen likaantumista sekä antaa lisätietoja likaantumiseen vaikuttavista tekijöistä.

Metsäenergian liiketoimintojen kehittäminen ja käytön kasvun vaikutukset Kaakkois-Suomessa

Kaakkois-Suomen alueella uusiutuvan energian käyttö ja erityisesti metsäenergian käyttö on kasvanut merkittävästi 2000-luvulla. Tulevaisuudessa metsäenergia nähdään edelleen potenti-aalisimpana vaihtoehtona korvattaessa fossiilisia polttoaineita lämpö- ja voimalaitoskokoluo-kassa. Muita uusiutuvan energian vaihtoehtoja ovat mm. tuuli- ja aurinkovoima, biokaasu sekä erilaiset kiinteät ja nestemäiset polttoainejalosteet. Tulevaisuudessa alueella voi olla mahdollis-ta tuottaa niin kansalliseen kuin kansainväliseen vientiin esim. biopolttonesteitä, biokaasua ja biohiiltä. Tutkimushankkeen tavoitteena oli selvittää metsäenergia-alan alueelliset toimijat sekä metsä-energian soveltuvuus ja liiketoimintamahdollisuudet Kaakkois-Suomen alueen energian tuo-tannossa. Tutkimus koostui seuraavista osatehtävistä: metsäsektorin toimijakentän kartoitus, metsäenergian alueelliset liiketoimintamahdollisuudet, puuperäisten polttoainejalosteiden käyttö- ja liiketoimintamahdollisuudet, muiden uusiutuvien energialähteiden käyttömahdolli-suudet ja vaikutukset Kaakkois-Suomessa. Tutkimuksessa arvioitiin myös Kaakkois-Suomen metsäenergian hankinnan työllisyysvaikutuksia. Tutkimuksen ohjausryhmänä toimi Kaakkois-Suomen metsäenergianeuvottelukunta. Tutkimuksessa kyselytutkimuksella selvitettiin metsäenergian tuottajien ja käyttäjien mielipi-teitä ja kehittämiskohteita toimialalta. Kaakkois-Suomessa hyödynnettävistä uusiutuvista energialähteistä selvitettiin nykyinen käyttö sekä arvioitiin tulevaisuuden hyödyntämismah-dollisuuksia vuonna 2020. Nämä tulokset esitettiin Kaakkois-Suomen energiataseen avulla. Kaakkois-Suomessa uusiutuvista energialähteistä puupolttoaineilla on merkittävin rooli metsä-teollisuuden johdosta ja alueen metsäenergian käyttö voi kasvaa jopa 1,7 TWh:in, mikäli fos-siilisia energialähteitä korvataan edelleen voimalaitoksissa ja lämpökeskuksissa. Metsäenergian käytön kasvussa alueen kunnilla on merkittävä rooli. Viime vuosina erityisesti tuulivoiman tuotanto on kasvanut ja tulee kasvamaan edelleen. Samoin aurinkoenergian hyödyntäminen kiinteistökokoluokassa on lisääntynyt voimakkaasti. Lisäksi maakuntaan on suunnitteilla kiin-teiden, nestemäisten ja kaasumaisten polttoainejalosteiden tuotantolaitoksia. Toteutuessaan laitokset voivat lisätä metsäenergian käyttöä merkittävästi.

CO2:n adsorptio Loviisan voimalaitoksen päästöilmasta 14C-päästöjen määrittämiseksi

Tämän kandidaatintyön tavoitteena oli selvittää mahdollisuuksia 14C:n kemiallisten muotojen eriyttämiseen käyttäen Loviisan voimalaitoksella olemassa olevaa näytteenkeräyslaitteistoa. Lisäksi tarkoituksena oli selvittää parhaiten tähän käyttötarkoitukseen soveltuva zeoliittityyppiä tyypeistä 4A, 5A ja 13X. Työn kirjallisessa osassa käsitellään ydinvoimalaitoksen C14-päästöjä keskittyen pääosin Loviisan VVER-laitokseen. Adsorption osalta esitellään kaupallisesti käytettyjä adsorptiomateriaaleja ja paneudutaan adsorptioon fysikaalisena ja kemiallisena ilmiönä. Lisäksi esitellään kahden desorptiomenetelmän perusperiaatteet. Kirjallisen osan lopussa kootaan tutkimukseen vaikuttavia tekijöitä ja esitellään aiemmin käytössä ollut näytteenkeräyslaitteisto. Kokeellisessa osassa esitellään työssä käytetyt laitteistot. Lisäksi on kuvattu mittausten suoritus nestetuikelaskurilla. Tämän jälkeen työssä esitellään mittaustuloksien käsittely ja näin saadut tulokset.

Chemical derivatization of galactoglucomannan for functional materials

In the framework of the biorefinery concept researchers aspire to optimize the utilization of plant materials, such as agricultural wastes and wood. For most of the known processes, the first steps in the valorisation of biomass are the extraction and purification of the individual components. The obtained raw products by means of a controlled separation can consecutively be modified to result in biofuels or biogas for energy production, but also in value-added products such as additives and important building blocks for the chemical and material industries. Considerable efforts are undertaken in order to substitute the use of oil-based starting materials or at least minimize their processing for the production of everyday goods. Wood is one of the raw materials, which have gained large attention in the last decades and its composition has been studied in detail. Nowadays, the extraction of water-soluble hemicelluloses from wood is well known and so for example xylan can be obtained from hardwoods and O-acetyl galactoglucomannans (GGMs) from softwoods. The aim of this work was to develop water-soluble amphiphilic materials of GGM and to assess their potential use as additives. Furthermore, GGM was also applied as a crosslinker in the synthesis of functional hydrogels for the removal of toxic metals and metalloid ions from aqueous solutions. The distinguished products were obtained by several chemical approaches and analysed by nuclear magnetic resonance spectroscopy (NMR), Fourier transform infrared spectroscopy (FTIR), size exclusion chromatography (SEC), thermal gravimetric analysis (TGA), scanning electron microscope SEM, among others. Bio-based surfactants were produced by applying GGM and different fatty acids as starting materials. On one hand, GGM-grafted-fatty acids were prepared by esterification and on the other hand, well-defined GGM-block-fatty acid derivatives were obtained by linking amino-functional fatty acids to the reducing end of GGM. The reaction conditions for the syntheses were optimized and the resultant amphiphilic GGM derivatives were evaluated concerning their ability to reduce the surface tension of water as surfactants. Furthermore, the block-structured derivatives were tested in respect to their applicability as additives for the surface modification of cellulosic materials. Besides the GGM surfactants with a bio-based hydrophilic and a bio-based hydrophobic part, also GGM block-structured derivatives with a synthetic hydrophobic tail, consisting of a polydimethylsiloxane chain, were prepared and assessed for the hydrophobization of surface of nanofibrillated cellulose films. In order to generate GGM block-structured derivatives containing a synthetic tail with distinguished physical and chemical properties, as well as a tailored chain length, a controlled polymerization method was used. Therefore, firstly an initiator group was introduced at the reducing end of the GGM and consecutively single electron transfer-living radical polymerization (SET-LRP) was performed by applying three different monomers in individual reactions. For the accomplishment of the synthesis and the analysis of the products, challenges related to the solubility of the reactants had to be overcome. Overall, a synthesis route for the production of GGM block-copolymers bearing different synthetic polymer chains was developed and several derivatives were obtained. Moreover, GGM with different molar masses were, after modification, used as a crosslinker in the synthesis of functional hydrogels. Hereby, a cationic monomer was used during the free radical polymerization and the resultant hydrogels were successfully tested for the removal of chromium and arsenic ions from aqueous solutions. The hydrogel synthesis was tailored and materials with distinguished physical properties, such as the swelling rate, were obtained after purification. The results generated in this work underline the potential of bio-based products and the urge to continue carrying out research in order to be able to use more green chemicals for the manufacturing of biorenewable and biodegradable daily products.

Teollinen symbioosi - kansallisen ohjelman toteuttaminen Suomessa Britanniaan verrattuna

This master thesis examines the possibility of implementing a national industrial symbiosis programme in Finland. Industrial symbiosis is a close cooperation between companies in which the actors make use of each other's wastes and by-products as raw materials for pro-cesses. Symbiosis programme aims to promote industrial symbiosis by identifying possible synergies. In the United Kingdom (UK), a national level programme NISP (National Industri-al Symbiosis Programme) has been successfully implemented. This thesis studies whether it would be possible to implement a similar program in Finland. The implementation of the pro-gram in Finland is evaluated by analyzing and comparing Finnish and British business envi-ronments using PESTEL and diamond models. The goal is to identify factors that promote or hinder the implementation of the programme in Finland. Based on this study, it can be said that implementing the programme in Finland is possible. The programme can be carried out in almost the same principles as in the UK, but some char-acteristics of the Finnish business environment, such as the high level of technological know-how, should especially be taken as an advantage. On the other hand, there are features, such as low level domestic demand, which may prevent the implementation of the program unless they are given special attention.

AQUAREL CONCEPT Aquatic resources for green energy realization

The AQUAREL project studied the availability and optional utilization methods for fish processing side streams and other aquatic biomaterial in the Republic of Karelia. Additionally processing aquatic biomaterial with manure and sewage sludge was studied. Based on the results, the most feasible option today is to process fish side streams to fish oil and dewatered oil-free residue and to use them for fish or animal feed production. However, it is necessary to highlight, that changes in e.g. economic environment, energy prices and demand may require re-evaluating the results and conclusions made in the project. Producing fish oil from fish processing side streams is an easy and relatively simple production process generating a valuable end product. The functionality of the process was confirmed in a pilot conducted in the project. The oil and solids are separated from the heated fish waste based on gravity. The fish oil separating on top of the separator unit is removed. Fish oil can as such be utilized for heating purposes, fish meal or animal feed production, but it can also be further processed to biodiesel. However, due to currently moderate energy prices in Russia, biodiesel production is not economically profitable. Even if the fish oil production process is not complicated, the operative management of small-scale fish oil production unit requires dedicated resources and separate facilities especially to meet hygiene requirements. Managing the side streams is not a core business for fish farmers. Efficient and economically profitable fish oil production requires a centralized production unit with bigger processing capacity. One fish processing unit needs to be designed to manage side streams collected from several fish farms. The optimum location for the processing unit is in the middle of the fish farms. Based on the transportation cost analysis in the Republic of Karelia, it is not economically efficient to transport bio-wastes for more than 100 km since the transportation costs start increasing substantially. Another issue to be considered is that collection of side streams, including the dead fish, from the fish farms should be organized on a daily basis in order to eliminate the need for storing the side streams at the farms. Based on AQUAREL project studies there are different public funding sources available for supporting and enabling profitable and environmentally sustainable utilization, research or development of fish processing side streams and other aquatic biomaterial. Different funding programmes can be utilized by companies, research organizations, authorities and non-governmental organizations.