Chelating Adsorbents in Purification of Hydrometallurgical Solutions

In this thesis, equilibrium and dynamic sorption properties of weakly basic chelating adsorbents were studied to explain removal of copper, nickel from a concentrated zinc sulfate solution in a hydrometallurgical process. Silica-supported chelating composites containing either branched poly(ethyleneimine) (BPEI) or 2-(aminomethyl)pyridine (AMP) as a functional group were used. The adsorbents are commercially available from Purity Systems Inc, USA as WP-1® and CuWRAM®, respectively. The fundamental interactions between the adsorbents, sulfuric acid and metal sulfates were studied in detail and the results were used to find the best conditions for removal of copper and nickel from an authentic ZnSO4 process solution. In particular, the effect of acid concentration and temperature on the separation efficiency was considered. Both experimental and modeling aspectswere covered in all cases. Metal sorption is considerably affected by the chemical properties of the studied adsorbents and by the separation conditions. In the case of WP-1, acid affinity is so high that column separation of copper, nickel and zinc has to be done using the adsorbent in base-form. On the other hand, the basicity of CuWRAM is significantly lower and protonated adsorbent can be used. Increasing temperature decreases the basicity and the metals affinity of both adsorbents, but the uptake capacities remain practically unchanged. Moreover, increasing temperature substantially enhances intra-particle mass transport and decreases viscosities thus allowing significantly higher feed flow rates in the fixed-bed separation. The copper selectivity of both adsorbents is very high even in the presence of a 250-fold excess of zinc. However, because of the basicity of WP-1, metal precipitation is a serious problem and therefore only CuWRAM is suitable for the practical industrial application. The optimum temperature for copper removal appears to be around 60 oC and an alternative solution purification method is proposed. The Ni/Zn selectivity of both WP-1 and CuWRAM is insufficient for removal of the very small amounts of nickel present in the concentrated ZnSO4 solution.

Artificial Ribonucleases: Oligonucleotides Conjugated with Metal Ion Chelates of Azacrowns

Ribonucleic acid (RNA) has many biological roles in cells: it takes part in coding, decoding, regulating and expressing of the genes as well as has the capacity to work as a catalyst in numerous biological reactions. These qualities make RNA an interesting object of various studies. Development of useful tools with which to investigate RNA is a prerequisite for more advanced research in the field. One of such tools may be the artificial ribonucleases, which are oligonucleotide conjugates that sequence-selectively cleave complementary RNA targets. This thesis is aimed at developing new efficient metal-ion-based artificial ribonucleases. On one hand, to solve the challenges related to solid-supported synthesis of metal-ion-binding conjugates of oligonucleotides, and on the other hand, to quantify their ability to cleave various oligoribonucleotide targets in a pre-designed sequence selective manner. In this study several artificial ribonucleases based on cleaving capability of metal ion chelated azacrown moiety were designed and synthesized successfully. The most efficient ribonucleases were the ones with two azacrowns close to the 3´- end of the oligonucleotide strand. Different transition metal ions were introduced into the azacrown moiety and among them, the Zn2+ ion was found to be better than Cu2+ and Ni2+ ions.

Effect of soil-spraying time on root-colonization ability of antagonistic Streptomyces griseoviridis

Selostus: Kasvualustan käsittelyajan vaikutus Streptomyces griseoviridis -antagonistin juurten asutuskykyyn

Arsenic and heavy metal concentrations in agricultural soils in South Savo province

Selostus: Etelä-Savon viljelysmaan arseeni- ja raskasmetallipitoisuudet

Heavy-metal pollution and remediation of forest soil around the Harjavalta Cu-Ni smelter, in SW Finland

Abstract

Management of Metals in the Pulping Process

Diplomityön tarkoituksena oli löytää keino korkean mangaanipitoisuuden hallintaan ECF-valkaisussa. Kirjallisuusosassa käsiteltiin eri metallien ja kuidun vuorovaikutuksia sekä niiden vaikutuksia prosessiin. Lisäksi käytiin läpi sellunvalmituksen yleisimpiä metallienhallintamenetelmiä. Työn kokeellisessa osassa tehtiin esikokeina laboratoriokokeita, jotta löydettiin oikeat kelatointistrategiat tehdasmittakaavan koeajoille. Laboratoriovalkaisut suoritettiin kuudella eri kemikaalilla käyttäen DD3-pesurin jälkeistä massaa ja samanlaisia parametrejä kuin tehdasvalkaisussa. Kolmesta eri valkaisusekvenssistä paras tulos saavutettiin D0-QEP-sekvenssillä. Tehdasmittakaavan koeajojen tavoitteena oli saavuttaa alle 1 mg/kg jäännösmangaanipitoisuus valkaistussa massassa ja korkeampi vaaleus EOP-vaiheessa pienemmällä klooridioksidin kulutuksella. Koeajoissa käytettiinDTPA:ta ja EDTA:ta kahdeksassa eri koepisteessä. Pienimpiin jäännöspitoisuuksiin päästiin koepisteissä, joissa kelatointiaine annosteltiin ennen valkaisun viimeistä pesuvaihetta tai sen jälkeen. Samanlaisia tuloksia saavutettiin koepisteissä, joissa kelatointiaine lisättiin suoraan EOP-vaiheeseen. Tällöin kelatointiaineen käyttö johti myös korkeampaan vaaleuteen EOP-vaiheessa pienemmällä kappakertoimella kuin referenssissä. Säästöt klooridioksidin kulutuksessa eivät olleet kuitenkaan tarpeeksi suuret kattaakseen kelatointiaineiden käytön kustannuksia. Kustannustehokkain tapa kontrolloida jäännösmangaanipitoisuutta oli EDTA:n annostelu D2 DD-pesurin jälkeen. Haittapuolena tälläisessä kelatoinnissa oli metallikompleksien palautuminen valkaisuun kuivauskoneen kiertoveden mukana. Tärkeimmät onnistuneeseen kelatointiin vaikuttavat parametrit olivat lajittelussa käytetyn rikkihapon annos, D0-vaiheen pH ja D0 DD-pesurin pesutehokkuus.

Logistics Management in China's Development Zones - Finnish Metal Industry Perspective

Alikehittynyt infrastruktuuri, tiukat säädökset ja säädösten tulkitseminen, sekä monimutkaiset verotuskäytännöt ovat aiheuttaneet ongelmia suomalaisille Alikehittynyt infrastruktuuri, tiukat säädökset ja säädösten tulkitseminen, sekä monimutkaiset verotuskäytännöt ovat aiheuttaneet ongelmia suomalaisille yrityksille Kiinassa. Tutkimuksen perusteella yritykset eivät pysty vaikuttamaan infrastruktuurin kehittymiseen tai säädösten implementointiin, mutta ylläpitämällä suhteita ja valitsemalla oikeat partnerit yritykset pystyvät hallitsemaan ongelma-alueitaan. Etenkin ulkomaalaisille yrityksille oikean logistiikkaoperaattorin valinta on tärkeätä ja huomioon ottaen palvelutason, kulttuuritaustan sekä kansainväliset operaatiot on ulkomaalaisten yritysten tehokkaampaa käyttää kansainvälisiä operaattoreita kuin paikallisia toimijoita, jotkaovat usein halvempia, mutta eivät pysty toimimaan kansainvälisellä tasolla. Vientiin keskittyneiden yritysten tulisi sijoittua vapaakauppa-alueille tai vientiin painottuneille teollisuusalueille. Kyseisillä alueilla liiketoiminta mannermaahan on rajoitettu, eivätkä alueet täten sovellu yrityksille, jotka ovat keskittyneet Kiinan markkinoille. Paikallisesti operoivien yritysten tulisi sijoittua normaaleihin teollisuuspuistoihin ja käyttää tullin valvomia varastoja tukemaan kansainvälisiä toimintojaan.Tulisi myös muistaa etteivät kiinalaiset teollisuuspuistot täytä kansainvälisiä kriteerejä, joten säädöksiin on tärkeätä tutustua huolella jamielipiteitä kerätä toisilta yrityksiltä. Kiinassa merkittävimmät logistiikkaongelmat ilmenevät tuonnin ja viennin yhteydessä, jolloin säädökset ja toimintamallit ovat kontrolloidumpia. Etenkin tullaus- ja arvonlisävero ongelmat liittyvät kiinteästi tuonti- ja vientiprosessiin. Tutkimuksen tulokset osoittivat, että tullausprosessi tehostuu yhteistyön ja koulutuksen kautta, mutta arvonlisäverosta aiheutuvien kustannusten minimointi vaatii logistiikkapuistojen käyttöä. Mikäli asiakas haluaa tehdä tullauksen kotiprovinssissaan tai yritys tekee kauppaa ALV -vapautettujen yritysten kanssa, tulisi logistiikkapuistojen käyttöä lisätä. Käytettäessä logistiikkapuistoja yritykset välttävät tuotteiden kuljetukset Hongkongiin jatakaisin säästäen huomattavasti kustannuksissa ja toimitusajoissa. Logistiikkapuistoja on myös mahdollista käyttää ratkaisuna kasvaviin ja viivästyviin ALV palautuksiin. Tutkimuksen tulosten mukaan toimintaympäristö ja vientipainotteinen valmistus ohjaavat 3PL yritysten valintaa ja vaihtoehtoisten logistiikkapalvelujen implementointia. Etabloiduttaessavapaakauppa-alueille vientiin ja tuontiin liittyvät ongelmatekijät vahvistuvat sekä rajoitukset kiinan liiketoimintaan kasvavat, mikä tekee yhteistyönkansainvälisten logistiikkaoperaattoreiden kanssa välttämättömäksi ja kannustaa hyödyntämään logistiikkapuistoja.

Kylmämuokatun austeniittisen ruostumattoman teräsputkipalkin hitsaus

Diplomityön tavoitteena on selvittää kylmälujitetusta austeniittisesta ruostumattomasta teräksestä valmistettavan putkipalkin pituussuunnassa hitsaamalla tapahtuvaa valmistusta. Työssä tarkastellaan eri hitsausprosessien lämmöntuonnin ja putkipalkin kylmämuovaamalla tapahtuvan valmistuksen ja hitsin jälkikäsittelynvaikutuksia putkipalkin pituushitsin mekaanisiin ominaisuuksiin. Teoriaosassa on perehdytty austeniittisen ruostumattoman teräksen hitsaukseen, kylmämuokkaamalla lujitetun teräksen käyttäytymiseen hitsauksessa, monipoltinkaari-, TIG-suurtaajuuspulssi- ja kaariavusteiseen laserhitsaukseen. Kokeellisessa osassaon suoritettu koehitsauksia edellä mainituilla menetelmillä kylmälujitetulle austeniittiselle ruostumattomalle teräkselle ja suoritettu saatujen koehitsien mekaanisien ominaisuuksien arviointia. Saatujen koetulosten perusteella ontodettu, että huolimatta hitsauksen lämmöntuonnin kylmämuokatun teräksen lujuusarvoja alentavasta vaikutuksesta on mahdollista valmistaa hitsin osalta perusaineen lujuusluokituksen täyttäviä putkipalkkeja. Tämä johtuu putkipalkin kylmämuovaamalla tapahtuvan valmistuksen ja hitsin jälkikäsittelyn hitsauksessa pehmentyneen vyöhykkeen lujuusarvoja takaisin perusaineen tasolle palauttavasta vaikutuksesta.

A support system for evaluating a suitable joining method in the production of sheet metal goods

This report illustrates a comparative study of various joining methods involved in sheet metal production. In this report it shows the selection of joining methods, which includes comparing the advantages and disadvantages of a method over the other ones and choosing the best method for joining. On the basis of various joining process from references, a table is generated containing set of criterion that helps in evaluation of various sheet metal joining processes and in selecting the most suitable process for a particular product. Three products are selected and a comprehensive study of the joining methods is analyzed with the help of various parameters. The table thus is the main part of the analysis process of this study and can be advanced with the beneficial results. It helps in a better and easy understanding and comparing the various methods, which provides the foundation of this study and analysis. The suitability of the joining method for various types of cases of different sheet metal products can be tested with the help of this table. The sections of the created table display the requirements of manufacturing. The important factor has been considered and given focus in the table, as how the usage of these parameters is important in percentages according to particular or individual case. The analysis of the methods can be extended or altered by changing the parameters according to the constraint. The use of this table is demonstrated by pertaining the cases from sheet metal production.

Value added logistical support service Part 2. Outsourcing process of spare part logistics in metal industry

The aim of this research study was to find out guidelines for outsourcing of logistics processes. The study was outlined to spare parts and `business-to-business' (B2B) markets in metal industry. This study can be applied as a manual for outsourcing especially warehousing and transportation activities. The study also touches other important areas of spare part logistics like manufacturing, customer service, procurement, quality control, reverse and recycling logistics, logistics technologies and valueadded services. The method of study consisted of three areas. Firstly exchanging views with logistics experts in participating companies, and secondly compiling material based on author's practical experience in logistics business with several international and domestic logistics service providers and vendors. Thirdlythe study includes also references to literature material. Due to the fact thatthe outsourcing of logistics functions can be handled widely and from differentpoint of views, in this study it is concentrated mainly on giving general levelguidelines for defining logistics strategy, hints both for tendering process and implementation project, and not forgetting the aftercare of business partnership.

Freezing Point Depressions of Dilute Solutions of Alkali Metal Chlorides and Bromides

Freezing point depressions (¿Tf) of dilute solutions of several alkali metal chlorides and bromides were calculated by means of the best activity coefficient equations. In the calculations, Hückel, Hamer and Pitzer equationswere used for activity coefficients. The experimental ¿Tf values available in the literature for dilute LiCl, NaCl and KBr solutions can be predicted within experimental error by the Hückel equations used. The experimental ¿Tf values for dilute LiCl and KBr solutions can also be accurately calculated by corresponding Pitzer equations and those for dilute NaCl solutions by the Hamer equation for this salt. Neither Hamer nor Pitzer equations predict accurately the freezing points reported in the literature for LiBr and NaBr solutions. The ¿Tf values available for dilute solutions of RbCl, CsCl or CsBr are not known at the moment accurately because the existing data for these solutions are not precise. The freezing point depressions are tabulated in the present study for LiCl, NaCl and KBr solutions at several rounded molalities. The ¿Tf values in this table can be highly recommended. The activity coefficient equations used in the calculation of these values have been tested with almost allhigh-precision electrochemical data measured at 298.15 K.

Formation and Control of Trace Metal Emissions in Co-Firing of Biomass, Peat, and Wastes in Fluidised Bed Combustors

Environmentally harmful consequences of fossil fuel utilisation andthe landfilling of wastes have increased the interest among the energy producers to consider the use of alternative fuels like wood fuels and Refuse-Derived Fuels, RDFs. The fluidised bed technology that allows the flexible use of a variety of different fuels is commonly used at small- and medium-sized power plants ofmunicipalities and industry in Finland. Since there is only one mass-burn plantcurrently in operation in the country and no intention to build new ones, the co-firing of pre-processed wastes in fluidised bed boilers has become the most generally applied waste-to-energy concept in Finland. The recently validated EU Directive on Incineration of Wastes aims to mitigate environmentally harmful pollutants of waste incineration and co-incineration of wastes with conventional fuels. Apart from gaseous flue gas pollutants and dust, the emissions of toxic tracemetals are limited. The implementation of the Directive's restrictions in the Finnish legislation is assumed to limit the co-firing of waste fuels, due to the insufficient reduction of the regulated air pollutants in the existing flue gas cleaning devices. Trace metals emission formation and reduction in the ESP, the condensing wet scrubber, the fabric filter, and the humidification reactor were studied, experimentally, in full- and pilot-scale combustors utilising the bubbling fluidised bed technology, and, theoretically, by means of reactor model calculations. The core of the model is a thermodynamic equilibrium analysis. The experiments were carried out with wood chips, sawdust, and peat, and their refuse-derived fuel, RDF, blends. In all, ten different fuels or fuel blends were tested. Relatively high concentrations of trace metals in RDFs compared to the concentrations of these metals in wood fuels increased the trace metal concentrations in the flue gas after the boiler ten- to hundred-folds, when RDF was co-fired with sawdust in a full-scale BFB boiler. In the case of peat, lesser increase in trace metal concentrations was observed, due to the higher initial trace metal concentrations of peat compared to sawdust. Despite the high removal rate of most of the trace metals in the ESP, the Directive emission limits for trace metals were exceeded in each of the RDF co-firing tests. The dominat trace metals in fluegas after the ESP were Cu, Pb and Mn. In the condensing wet scrubber, the flue gas trace metal emissions were reduced below the Directive emission limits, whenRDF pellet was used as a co-firing fuel together with sawdust and peat. High chlorine content of the RDFs enhanced the mercuric chloride formation and hence the mercury removal in the ESP and scrubber. Mercury emissions were lower than theDirective emission limit for total Hg, 0.05 mg/Nm3, in all full-scale co-firingtests already in the flue gas after the ESP. The pilot-scale experiments with aBFB combustor equipped with a fabric filter revealed that the fabric filter alone is able to reduce the trace metal concentrations, including mercury, in the flue gas during the RDF co-firing approximately to the same level as they are during the wood chip firing. Lower trace metal emissions than the Directive limits were easily reached even with a 40% thermal share of RDF co-firing with sawdust.Enrichment of trace metals in the submicron fly ash particle fraction because of RDF co-firing was not observed in the test runs where sawdust was used as the main fuel. The combustion of RDF pellets with peat caused an enrichment of As, Cd, Co, Pb, Sb, and V in the submicron particle mode. Accumulation and release oftrace metals in the bed material was examined by means of a bed material analysis, mass balance calculations and a reactor model. Lead, zinc and copper were found to have a tendency to be accumulated in the bed material but also to have a tendency to be released from the bed material into the combustion gases, if the combustion conditions were changed. The concentration of the trace metal in the combustion gases of the bubbling fluidised bed boiler was found to be a summary of trace metal fluxes from three main sources. They were (1) the trace metal flux from the burning fuel particle (2) the trace metal flux from the ash in the bed, and (3) the trace metal flux from the active alkali metal layer on the sand (and ash) particles in the bed. The amount of chlorine in the system, the combustion temperature, the fuel ash composition and the saturation state of the bed material in regard to trace metals were discovered to be key factors affecting therelease process. During the co-firing of waste fuels with variable amounts of e.g. ash and chlorine, it is extremely important to consider the possible ongoingaccumulation and/or release of the trace metals in the bed, when determining the flue gas trace metal emissions. If the state of the combustion process in regard to trace metals accumulation and/or release in the bed material is not known,it may happen that emissions from the bed material rather than the combustion of the fuel in question are measured and reported.

Metal surface and subsurface inspection using nondestructive optical methods

This thesis considers nondestructive optical methods for metal surface and subsurface inspection. The main purpose of this thesis was to study some optical methods in order to find out their applicability to industrial measurements. In laboratory testing the simplest light scattering approach, measurement of specular reflectance, was used for surface roughness evaluation. Surface roughness, curvature and finishing process of metal sheets were determined by specular reflectance measurements. Using a fixed angleof incidence, the specular reflectance method might be automated for industrialinspection. For defect detection holographic interferometry and thermography were compared. Using either holographic interferometry or thermography, relativelysmall-size defects in metal plates could be revealed. Holographic techniques have some limitations for industrial measurements. On the contrary, thermography has excellent prospects for on-line inspection, especially with scanning techniques.