Wooden packaging waste reuse and refining

The aim of the thesis was both to study wooden packaging waste reuse and refining generated in the forestry machine factory environment, and to find alternative wooden packaging waste utilization options in order to create a new operating model which would decrease the overall amount of waste produced. As environmental and waste legislation has become more rigid and companies' own environmental management systems’ requirements and control have increased, companies have had to consider their environmental aspects more carefully. Companies have to take into account alternative ways of reducing waste through an increase in reuse and recycling. A part of this waste is from different forms of packaging. In the metal industry the most heavily used packaging material is wooden packaging, as such material is heavy and the packaging has to be able to bear heavy stress. In the theoretical part of the thesis, the requirements of packaging and packaging waste legislation, as well as environmental management systems governing companies’ processing of their packaging waste, are studied. The theoretical part includes a process study of systems, which direct packaging waste and wooden packaging waste refining. In addition, methods related to the continuous improvement of these processes are introduced. This thesis concentrates on designing and creating a new operating model in relation to wooden packaging waste processing. The main target was to find an efficient model in order to decrease the total amount of wooden packaging waste and to increase refining. The empirical part introduces methods for approaches to wooden packaging waste re-utilization, as well as a description of a new operating model and its impact.

Optimal processing chain for waste power plant

This study is done to examine waste power plant’s optimal processing chain and it is important to consider from several points of view on why one option is better than the other. This is to insure that the right decision is made. Incineration of waste has devel-oped to be one decent option for waste disposal. There are several legislation matters and technical options to consider when starting up a waste power plant. From the tech-niques pretreatment, burner and flue gas cleaning are the biggest ones to consider. The treatment of incineration residues is important since it can be very harmful for the envi-ronment. The actual energy production from waste is not highly efficient and there are several harmful compounds emitted. Recycling of waste before incineration is not very typical and there are not many recycling options for materials that cannot be easily re-cycled to same product. Life cycle assessment is a good option for studying the envi-ronmental effect of the system. It has four phases that are part of the iterative study process. In this study the case environment is a waste power plant. The modeling of the plant is done with GaBi 6 software and the scope is from gate-to-grave. There are three different scenarios, from which the first and second are compared to each other to reach conclusions. Zero scenario is part of the study to demonstrate situation without the power plant. The power plant in this study is recycling some materials in scenario one and in scenario two even more materials and utilize the bottom ash more ways than one. The model has the substitutive processes for the materials when they are not recycled in the plant. The global warming potential results show that scenario one is the best option. The variable costs that have been considered tell the same result. The conclusion is that the waste power plant should not recycle more and utilize bottom ash in a number of ways. The area is not ready for that kind of utilization and production from recycled materials.

Identification of the Emerging Issues in Recycled Fiber Processing

The objectives of this research work “Identification of the Emerging Issues in Recycled Fiber processing” are discovering of emerging research issues and presenting of new approaches to identify promising research themes in recovered paper application and production. The projected approach consists of identifying technological problems often encountered in wastepaper preparation processes and also improving the quality of recovered paper and increasing its proportion in the composition of paper and board. The source of information for the problem retrieval is scientific publications in which waste paper application and production were discussed. The study has exploited several research methods to understand the changes related to utilization of recovered paper. The all assembled data was carefully studied and categorized by applying software called RefViz and CiteSpace. Suggestions were made on the various classes of these problems that need further investigation in order to propose an emerging research trends in recovered paper.

Utilization of steelmaking waste materials for production of calcium carbonate (CaCO3)

The steel industry produces, besides steel, also solid mineral by-products or slags, while it emits large quantities of carbon dioxide (CO2). Slags consist of various silicates and oxides which are formed in chemical reactions between the iron ore and the fluxing agents during the high temperature processing at the steel plant. Currently, these materials are recycled in the ironmaking processes, used as aggregates in construction, or landfilled as waste. The utilization rate of the steel slags can be increased by selectively extracting components from the mineral matrix. As an example, aqueous solutions of ammonium salts such as ammonium acetate, chloride and nitrate extract calcium quite selectively already at ambient temperature and pressure conditions. After the residual solids have been separated from the solution, calcium carbonate can be precipitated by feeding a CO2 flow through the solution. Precipitated calcium carbonate (PCC) is used in different applications as a filler material. Its largest consumer is the papermaking industry, which utilizes PCC because it enhances the optical properties of paper at a relatively low cost. Traditionally, PCC is manufactured from limestone, which is first calcined to calcium oxide, then slaked with water to calcium hydroxide and finally carbonated to PCC. This process emits large amounts of CO2, mainly because of the energy-intensive calcination step. This thesis presents research work on the scale-up of the above-mentioned ammonium salt based calcium extraction and carbonation method, named Slag2PCC. Extending the scope of the earlier studies, it is now shown that the parameters which mainly affect the calcium utilization efficiency are the solid-to-liquid ratio of steel slag and the ammonium salt solvent solution during extraction, the mean diameter of the slag particles, and the slag composition, especially the fractions of total calcium, silicon, vanadium and iron as well as the fraction of free calcium oxide. Regarding extraction kinetics, slag particle size, solid-to-liquid ratio and molar concentration of the solvent solution have the largest effect on the reaction rate. Solvent solution concentrations above 1 mol/L NH4Cl cause leaching of other elements besides calcium. Some of these such as iron and manganese result in solution coloring, which can be disadvantageous for the quality of the PCC product. Based on chemical composition analysis of the produced PCC samples, however, the product quality is mainly similar as in commercial products. Increasing the novelty of the work, other important parameters related to assessment of the PCC quality, such as particle size distribution and crystal morphology are studied as well. As in traditional PCC precipitation process, the ratio of calcium and carbonate ions controls the particle shape; a higher value for [Ca2+]/[CO32-] prefers precipitation of calcite polymorph, while vaterite forms when carbon species are present in excess. The third main polymorph, aragonite, is only formed at elevated temperatures, above 40-50 °C. In general, longer precipitation times cause transformation of vaterite to calcite or aragonite, but also result in particle agglomeration. The chemical equilibrium of ammonium and calcium ions and dissolved ammonia controlling the solution pH affects the particle sizes, too. Initial pH of 12-13 during the carbonation favors nonagglomerated particles with a diameter of 1 μm and smaller, while pH values of 9-10 generate more agglomerates of 10-20 μm. As a part of the research work, these findings are implemented in demonstrationscale experimental process setups. For the first time, the Slag2PCC technology is tested in scale of ~70 liters instead of laboratory scale only. Additionally, design of a setup of several hundreds of liters is discussed. For these purposes various process units such as inclined settlers and filters for solids separation, pumps and stirrers for material transfer and mixing as well as gas feeding equipment are dimensioned and developed. Overall emissions reduction of the current industrial processes and good product quality as the main targets, based on the performed partial life cycle assessment (LCA), it is most beneficial to utilize low concentration ammonium salt solutions for the Slag2PCC process. In this manner the post-treatment of the products does not require extensive use of washing and drying equipment, otherwise increasing the CO2 emissions of the process. The low solvent concentration Slag2PCC process causes negative CO2 emissions; thus, it can be seen as a carbon capture and utilization (CCU) method, which actually reduces the anthropogenic CO2 emissions compared to the alternative of not using the technology. Even if the amount of steel slag is too small for any substantial mitigation of global warming, the process can have both financial and environmental significance for individual steel manufacturers as a means to reduce the amounts of emitted CO2 and landfilled steel slag. Alternatively, it is possible to introduce the carbon dioxide directly into the mixture of steel slag and ammonium salt solution. The process would generate a 60-75% pure calcium carbonate mixture, the remaining 25-40% consisting of the residual steel slag. This calcium-rich material could be re-used in ironmaking as a fluxing agent instead of natural limestone. Even though this process option would require less process equipment compared to the Slag2PCC process, it still needs further studies regarding the practical usefulness of the products. Nevertheless, compared to several other CO2 emission reduction methods studied around the world, the within this thesis developed and studied processes have the advantage of existing markets for the produced materials, thus giving also a financial incentive for applying the technology in practice.

Effects of feed processing on the apparent ileal digestibility of amino acids in pig diets containing wheat bran or wheat middlings

Selostus: Prosessoinnin vaikutus vehnän sivutuotteita sisältävien rehuseosten aminohappojen ohutsuolisulavuuteen sioilla

Stress intensity factor of wood from crack-tip displacement fields obtained from digital image processing

Abstract

Parhaat käyttökelpoiset tekniikat (BAT) perunankuorimoiden jätteiden käsittelyssä -käytäntöjä Euroopan maista

Yhä suurempi osa suurkeittiöistä ja ravintoloista käyttää ruuan valmistuksessa valmiiksi prosessoituja kasviksia, jotka hankitaan pääasiassa lähellä sijaitsevista tilakuorimoista. Kuorimoilla syntyy suuria määriä jätettä, enimmäkseen kuorijätteitä, multaa ja jätevettä. Tässä työssä tarkastellaan perunankuorimoiden kuorintamenetelmiä ja kuorintaprosessia, prosessissa syntyviä jätteitä ja niiden käsittelyä sekä ympäristöasioiden hallintamenetel-miä kuorimoilla Suomessa ja muissa EU-maissa. Työn tavoitteena oli selvittää, minkälainen on lainsäädäntö ja minkälaiset ovat kuorimotoimintaa koskevat lupakäytännöt Ruotsissa, Saksassa, Belgiassa ja Iso-Britanniassa. Lisäksi tavoitteena oli selvittää, onko näissä maissa määritelty, millainen on perunankuorimoille soveltuva paras käyttökelpoinen tekniikka (BAT) erityisesti jätteiden käsittelyssä. Euroopan yhteisön neuvoston direktiivi (96/61/EY) ympäristön pilaantumisen ehkäisemisen ja vähentämisen yhtenäistämiseksi edellyttää perunankuorimoilta toimintaansa ympäristöluvan. Laitosten koko, joilta ympäristölupa vaaditaan, vaihtelee suuresti eri maissa. Myös kuorimoiden jäteveden puhdistusvaatimukset vaihtelevat maittain. Belgi-assa ja Saksassa perunankuorimoilla syntyville jätevesille on asetettu päästöraja-arvot laissa. Kansallinen BAT-ohjeistus vihanneksia ja hedelmiä jatkojalostavalle teollisuudelleon tehty Belgiassa ja Iso-Britanniassa. Sen sijaan Saksassa ja Ruotsissa kansallista ohjeistusta ei ole tehty. Kansallisten BAT-ohjeistusten pohjalta Euroopan yhteisöjen komissio on julkaissut tammikuussa 2006 elintarviketeollisuudelle BAT-vertailuasiakirjan eli BREFin (BAT Referense Document), joissa kuvataan yleisellä tasolla BAT-tekniikoiksi sovitut tekniikat mm. perunan prosessoinnissa. Tässä työssä tuli ilmi, että kokoerot Suomen ja tässä työssä tarkasteltavien maiden kuo-rimoiden välillä ovat suuret. Voidaankin todeta, että tässä työssä tarkastelluissa BAT - ohjeistuksissa ja Euroopan komission BREF-dokumentissa esitetyt BAT-tekniikat etenkin jätevedenpuhdistuksessa eivät suoraan ole sovellettavissa Suomen olosuhteisiin kuorimoidemme pienestä koosta johtuen. Kiinteiden kuorintajätteiden käsittelyssä BAT-tekniikoiksi ulkomailla on määritelty lä-hinnä rehukäyttö, kompostointi ja peltoon levitys. Perunankuorimoiden jäteveden puhdistuksessa BAT-tekniikaksi Belgiassa on määritelty primääripuhdistus ja sekundääripuhdistus aerobisella menetelmällä. Iso-Britanniassapuolestaan BAT-tekniikkaa on primää-ripuhdistus, sekundääripuhdistus aerobisesti tai anaerobisesti ja tertiääripuhdistus, mikäli se on taloudellisesti mahdollista toteuttaa. Kuorijätteiden kompostointi on tällä hetkelläSuomessa melko harvinaista, sillä jätteiden suuri vesipitoisuus ja kylmä ilmastomme vaikeuttavat kompostointia. Kompostointimah-dollisuuksia ja kompostointiprosessin optimointia kuorintajätteille sopivaksi tulisikin tutkia tulevaisuudessa yhtenä jätteiden käsittelyvaihtoehtona. Kuorimoiden jätevesien puhdistuksessa tulevat Suomessa kysymykseen lähinnä yksinkertaiset kiinteistökohtaiset pienpuhdistamot, kuten panospuhdistamot. Pienpuhdistamolaitteistoihin liittyvää tutki-mus-ja kehitystyötä on viime vuosina tehty paljon ja sitä olisi tärkeää jatkaa edelleen, jotta löydettäisiin entistä kustannustehokkaampia ratkaisuja.

International comparison of Russian food processing industry -Finnish perspective

Työn päätavoitteena on kartoittaa Venäjän elintarviketeollisuutta ulkomaisen investoijan näkökulmasta. Tutkimus arvioi liiketoimintamahdollisuuksia ja kilpailutilannetta Venäjän elintarviketeollisuudessa ja auttaa ulkomaisia yrityksiä toteuttamaan liiketoimintastrategioitaan Venäjällä. Venäjän ja muiden siirtymätalousmaiden markkinatilannevertailujen lisäksi Venäjän alueita verrataan keskenään. Myös mahdollisen WTO jäsenyyden vaikutuksia arvioidaan. Kommunismin perintö vaikuttaa edelleen Venäjän elintarviketeollisuuteen ja maatalouteen. Maatalouden tuottavuus on kaukana länsimaisesta tasosta ja maatiloilta puuttuu rahoitusta. Etenkin maidon- ja lihanjalostajat kärsivät raaka-ainepulasta. Venäjän kriisi vuonna 1998 vahvisti paikallista teollisuustuotantoa mutta aiheutti ongelmia ulkomaisille investoijille ja yrityksille, jotka vievät tuotteitaan Venäjälle. Edut, joita mahdollinen maailmankauppajärjestö WTO:n jäsenyys tuo, ovat merkittävämpiä Venäjälle kuin sen kauppakumppaneille. Venäjän alueet eivät ole yhtäläisesti kehittyneitä ja kuluttajien ostovoima vaihtelee paljon. Itsestään selvin ja houkuttelevin vaihtoehto menestyvien elintarvikeyritysten laajentumiselle löytyy alueilta, joilla ostovoima on suurin. Tähän asti kansainväliset elintarvikeyritykset ovat olleet enemmän kiinnostuneita Itä- ja Keski-Euroopan maista. Käytettävissä olevat tulot ovat Itä- ja Keski-Euroopan maissa suurempia kuin Venäjällä, joten tuottajat pystyvät myymään myös kalliimpia tuotteita. Työvoimakustannukset Venäjällä tulevat olemaan suotuisia vielä muutaman vuosikymmenen ja markkinoiden koko on merkittävä. Siksi kansainvälisillä elintarvikeyrityksillä riittää kiinnostusta tulevaisuudessa investoida myös Venäjälle.

A Feasibility Study of a Pelleting Plant as an Option for By Product Upgrading in Wood-Processing Industry

Tämän kannattavuustutkimuksen lähtökohtana oli se, että Yhtyneet Sahat Oy:n Kaukaan sahalla ja Luumäen jatkojalostuslaitoksella haluttiin selvittää pellettitehtaan kannattavuus nykyisessä markkinatilanteessa. Tämä työon luonteeltaan teknis-taloudellinen selvitys eli ns. feasibility study. Pelletöintiprosessi on tekniikaltaan yksinkertainen eikä edellytä korkea teknologian laitteita. Toimiala on maailmanlaajuisesti varsin uusi. Suomessa pellettimarkkinat ovat vielä pienet ja kehittymättömät, mutta kasvua on viime vuosina tapahtunut. Valtaosa kotimaan tuotannosta menee vientiin. Investoinnin laskentaprosessissa saadut tuotannon alkuarvot sekä kustannusrakenteen määrittelyt ovat perustana varsinaisille kannattavuuslaskelmille. Laskelmista on selvitetty investointeihin liittyvät yleisimmät taloudelliset tunnusluvut ja herkimpiä muuttujia on tutkittu ja pohdittu herkkyysanalyysiä apuna käyttäen.

Challenges in packaging waste management: A case study in the fast food industry

The main research problem of this thesis is to find out the means of promoting the recovery of packaging waste generated in thefast food industry. The recovery of packaging waste generated in the fast food industry is demanded by the packaging waste legislation and expected by the public. The means are revealed by the general factors influencing the recovery of packaging waste, analysed by a multidisciplinary literature review and a case study focusing on the packaging waste managementof McDonald's Oy operating in Finland. The existing solid waste infrastructure does not promote the recovery ofpackaging waste generated in the fast food industry. The theoretical recovery rate of the packaging waste is high, 93 %, while the actual recovery rate is only 29 % consisting of secondary packaging manufactured from cardboard. The total recovery potential of packaging waste is 64 %, resulting in 1 230 tonnes ofrecoverable packaging waste. The achievable recovery potential of 33 %, equalling 647 tonnes of packaging waste could be recovered, but is not recovered mainly because of non-working waste management practises. The theoretical recovery potential of 31 %, equalling 583 tonnes of packaging waste can not be recovered by the existing solid waste infrastructure because of the obscure status of commecial waste, the improper operation ofproducer organisations, and the municipal autonomy. The sorting experiment indicated that it is possible to reach the achievable recovery potential inthe existing solid waste infrastructure. The achievement is promoted by waste producer -oriented waste management practises. The theoretical recovery potential can be reached by increasing the consistency of the solid waste infrastructure through governmental action.