Indoor air quality at a waste incineration plant in Finland

Waste has been incinerated for energy utilization for more than a hundred years, but the harmful emissions emitted from the incineration plants did not begin to cause concern until the 1980s. Many plants were shutdown and the waste incineration plant in Kyläsaari Helsinki was one of them. In later years, new landfill regulations have increased the interest in waste incineration. During the last year, four new plants were taken into operation in Finland, Westenergy in Vaasa among them. The presence of dust has been observed indoors at Westenergy waste incineration plant. Dust is defined as particles with a diameter above 10 μm, while fine particles have a diameter smaller than 2.5 μm, ultrafine under 0.1 μm and nanoparticles under 0.05 μm. In recent years, the focus of particle health research has been changed to investigate smaller particles. Ultrafine particles have been found to be more detrimental to health than larger particles. Limit values regulating the concentrations of ultrafine particles have not been determined yet. The objective of this thesis was to investigate dust and particles present inside the Westenergy waste incineration facility. The task was to investigate the potential pollutant sources and to give recommendations of how to minimize the presence of dust and particles in the power plant. The total particle number concentrations and size distributions where measured at 15 points inside the plant with an Engine Exhaust Particle Sizer (EEPS) Spectrometer. The measured particles were mainly in the ultrafine size range. Dust was only visually investigated, since the main purpose was to follow the dust accumulation. The measurement points inside the incineration plant were chosen according to investigate exposure to visitors and workers. At some points probable leakage of emissions were investigated. The measurements were carried out during approximately one month in March–April 2013. The results of the measurements showed that elevated levels of dust and particles are present in the indoor air at the waste incineration plant. The cleanest air was found in the control room, warehouse and office. The most polluted air was near the sources that were investigated due to possible leakage and in the bottom ash hall. However, the concentrations were near measured background concentrations in European cities and no leakage could be detected. The high concentrations were assumed to be a result of a lot of dust and particles present on surfaces that had not been cleaned in a while. The main source of the dust and particles present inside the waste incineration plant was thought to be particles and dust from the outside air. Other activities in the area around the waste incineration facility are ground work activities, stone crushing and traffic, which probably are sources of particle formation. Filtration of the outside air prior entering the facility would probably save personnel and visitors from nuisance and save in cleaning and maintenance costs.

Characterisation of waste for combustion : with special reference to the role of zinc

Waste combustion has gone from being a volume reducing discarding-method to an energy recovery process for unwanted material that cannot be reused or recycled. Different fractions of waste are used as fuel today, such as; municipal solid waste, refuse derived fuel, and solid recovered fuel. Furthermore, industrial waste, normally a mixture between commercial waste and building and demolition waste, is common, either as separate fuels or mixed with, for example, municipal solid waste. Compared to fossil or biomass fuels, waste mixtures are extremely heterogeneous, making it a complicated fuel. Differences in calorific values, ash content, moisture content, and changing levels of elements, such as Cl and alkali metals, are common in waste fuel. Moreover, waste contains much higher levels of troublesome trace elements, such as Zn, which is thought to accelerate a corrosion process. Varying fuel quality can be strenuous on the boiler system and may cause fouling and corrosion of heat exchanger surfaces. This thesis examines waste fuels and waste combustion from different angles, with the objective of giving a better understanding of waste as an important fuel in today’s fuel economy. Several chemical characterisation campaigns of waste fuels over longer time periods (10-12 months) was used to determine the fossil content of Swedish waste fuels, to investigate possible seasonal variations, and to study the presence of Zn in waste. Data from the characterisation campaigns were used for thermodynamic equilibrium calculations to follow trends and determine the effect of changing concentrations of various elements. The thesis also includes a study of the thermal behaviour of Zn and a full—scale study of how the bed temperature affects the volatilisation of alkali metals and Zn from the fuel. As mixed waste fuel contains considerable amounts of fresh biomass, such as wood, food waste, paper etc. it would be wrong to classify it as a fossil fuel. When Sweden introduced waste combustion as a part of the European Union emission trading system in the beginning of 2013 there was a need for combustion plants to find a usable and reliable method to determine the fossil content. Four different methods were studied in full-scale of seven combustion plants; 14Canalysis of solid waste, 14C-analysis of flue gas, sorting analysis followed by calculations, and a patented balance method that is using a software program to calculate the fossil content based on parameters from the plant. The study showed that approximately one third of the coal in Swedish waste mixtures has fossil origins and presented the plants with information about the four different methods and their advantages and disadvantages. Characterisation campaigns also showed that industrial waste contain higher levels of trace elements, such as Zn. The content of Zn in Swedish waste fuels was determined to be approximately 800 mg kg-1 on average, based on 42 samples of solid waste from seven different plants with varying mixtures between municipal solid waste and industrial waste. A review study of the occurrence of Zn in fuels confirmed that the highest amounts of Zn are present in waste fuels rather than in fossil or biomass fuels. In tires, Zn is used as a vulcanizing agent and can reach concentration values of 9600-16800 mg kg-1. Waste Electrical and Electronic Equipment is the second Zn-richest fuel and even though on average Zn content is around 4000 mg kg-1, the values of over 19000 mg kg-1 were also reported. The increased amounts of Zn, 3000-4000 mg kg-1, are also found in municipal solid waste, sludge with over 2000 mg kg-1 on average (some exceptions up to 49000 mg kg-1), and other waste derived fuels (over 1000 mg kg-1). Zn is also found in fossil fuels. In coal, the average level of Zn is 100 mg kg-1, the higher amount of Zn was only reported for oil shale with values between 20-2680 mg kg-1. The content of Zn in biomass is basically determined by its natural occurrence and it is typically 10-100 mg kg-1. The thermal behaviour of Zn is of importance to understand the possible reactions taking place in the boiler. By using thermal analysis three common Zn-compounds were studied (ZnCl2, ZnSO4, and ZnO) and compared to phase diagrams produced with thermodynamic equilibrium calculations. The results of the study suggest that ZnCl2(s/l) cannot exist readily in the boiler due to its volatility at high temperatures and its conversion to ZnO in oxidising conditions. Also, ZnSO4 decomposes around 680°C, while ZnO is relatively stable in the temperature range prevailing in the boiler. Furthermore, by exposing ZnO to HCl in a hot environment (240-330°C) it was shown that chlorination of ZnO with HCl gas is possible. Waste fuel containing high levels of elements known to be corrosive, for example, Na and K in combination with Cl, and also significant amounts of trace elements, such as Zn, are demanding on the whole boiler system. A full-scale study of how the volatilisation of Na, K, and Zn is affected by the bed temperature in a fluidised bed boiler was performed parallel with a lab-scale study with the same conditions. The study showed that the fouling rate on deposit probes were decreased by 20 % when the bed temperature was decreased from 870°C to below 720°C. In addition, the lab-scale experiments clearly indicated that the amount of alkali metals and Zn volatilised depends on the reactor temperature.

Importance of considering food waste in the development of sustainable food packaging systems

Meeting the needs of both present and future generations forms the foundation of sustainable development. Concern about food demand is increasing alongside the continuously growing population. In the pursuit of food security preventing food waste is one solution avoiding the negative environmental impacts that result from producing food unnecessarily. Packages offer one answer to preventing food waste, as they 1) preserve and protect food, 2) introduce the user to the correct way to handle and use the food and package and 3) allow the user to consume the food in its entirety. This thesis aims to enhance the sustainability of food packages by giving special emphasis to preventing food waste. The focus of this thesis is to assist the packaging designer in being able to take into account the requirements for the sustainability of food packages and to be able to integrate these requirements into the product development process. In addition, life cycle methods that can be used as a tool in the packaging design process or in assessing the sustainability of finished food-packaging combinations are evaluated. The methods of life cycle costing (LCC) and life cycle working environment (LCWE) are briefly discussed. The method of life cycle assessment (LCA) is examined more thoroughly through the lens of the literature review of food-package LCA case studies published in the 21st century in three relevant journals. Based on this review and on experiences learned from conducting LCAs, recommendations are given as to how the LCA practitioner should conduct a food packaging study to make most of the results. Two case studies are presented in this thesis. The first case study relates the results of a life cycle assessment conducted for three food items (cold cut (ham), sliced dark bread (rye) and Soygurt drink) and the alternative packaging options of each. Results of this study show that the packaging constitutes only 1–12 % of the total environmental impacts of the food-packaging combination. The greatest effect is derived from the food itself and the wasted food. Even just a small percentage of wasted food causes more environmental impacts than does the packaging. The second case study presents the results of LCC and LCWE analysis done for fruit and vegetable transport packages. In this thesis, the specific results of the study itself are not the focus, but rather the study methods and scope are analysed based on how these complement the sustainability assessment of food packages. This thesis presents reasons why prevention of food waste should be more thoroughly taken into account in food packaging design. In addition, the task of the packaging designer is facilitated by the requirements of sustainable food packaging, by the methods and step-by-step guidance on how to integrate sustainability issues into the design process, and by the recommendations on how to assess the sustainability of food packages. The intention of this thesis is to express the issues that are important in the field of the food packaging industry. Having recognised and implemented these issues, businesses can better manage the risks that could follow from neglecting these sustainability aspects.

Association between Information and Communication Technology Usage and the Quality of Sleep among School-Aged Children during a School Week

ilm OKM 2013

Voimalaitostuhkan Hyödyntämismahdollisuudet - Case: Kouvolan Seutu

Maailman laajuisen kasvihuoneilmiön kiihtyminen ja EU:n tiukentuneet jäsenmailleen asettamat tavoitteet uusiutuvien polttoaineiden käytön lisäämiseksi ovat lisänneet puupolttoaineiden käyttöä Suomessa. Lisääntynyt puupolttoaineiden käyttö ja entistä tehokkaampi hakkuutähteiden hyödyntäminen on lisännyt metsistä poistuvien ravinteiden määrää. Huoli metsien maaperän ravinteiden niukkenemisesta sekä tiukentunut lainsäädäntö tuhkien kaatopaikkasijoittamisesta ovat lisänneet energiayhtiöiden kiinnostusta lisätä tuhkien hyötykäyttöä. Tuhka täytyy esikäsitellä, eli stabiloida ennen hyötykäyttöä. Stabiloinnissa tuhkaa kostutetaan, jolloin siitä muodostuu rakeita. Hyödynnettäessä tuhkaa metsälannoitukseen tuhka tulee usein myös terästää typellä, sillä tuhka ei sisällä lainkaan typpeä. Muita tuhkan hyötykäyttömahdollisuuksia ovat peltolannoitus, betonin valmistus, maarakentaminen sekä jätevedenpuhdistus. Näistä vaihtoehdoista betonin valmistus ja maarakentaminen ovat melko yleisiä. Kouvolassa tuhkaa muodostuu noin 14 000 tonnia vuodessa. Kaupungin omistama metsäalue Saaramaalla voitaisiin lannoittaa lähes samoilla kustannuksilla kuin mitä kaatopaikkasijoittaminen maksaisi. Sen sijaan tuhkan käytöllä tierakentamiseen Tähteen alueella saavutetaan tuhansien eurojen säästöt kaatopaikkasijoitukseen verrattuna ja samalla tuhka saadaan hyötykäyttöön kiviaineksia säästäen.  

Industrial-Scale hydrothermal carbonization of waste sludge materials for fuel production

Hydrothermal carbonization (HTC) is a thermochemical process used in the production of charred matter similar in composition to coal. It involves the use of wet, carbohydrate feedstock, a relatively low temperature environment (180 °C-350 °C) and high autogenous pressure (up to 2,4 MPa) in a closed system. Various applications of the solid char product exist, opening the way for a range of biomass feedstock materials to be exploited that have so far proven to be troublesome due to high water content or other factors. Sludge materials are investigated as candidates for industrial-scale HTC treatment in fuel production. In general, HTC treatment of pulp and paper industry sludge (PPS) and anaerobically digested municipal sewage sludge (ADS) using existing technology is competitive with traditional treatment options, which range in price from EUR 30-80 per ton of wet sludge. PPS and ADS can be treated by HTC for less than EUR 13 and 33, respectively. Opportunities and challenges related to HTC exist, as this relatively new technology moves from laboratory and pilot-scale production to an industrial scale. Feedstock materials, end-products, process conditions and local markets ultimately determine the feasibility of a given HTC operation. However, there is potential for sludge materials to be converted to sustainable bio-coal fuel in a Finnish context.

Exposing usage and workflow in a DSpace repository

Poster at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

The usage of experimental research in business-to-business marketing context in academic marketing journals

The aim of this master’s thesis is to introduce what is experimental research and how the researcher is able to use this researching method in business-to-business context. This work has been done with analyzing articles of four academic marketing journals from years 1992-2012. In the literature part there is introduction of the nature of the experimental research, its terminology and design. There is also discussion about limitations of experimental research and comparison of experimental research to quasi-experimental design. In the results part there is a review how experimental research has been used in the business-to-business context in the past two decades. In the analysis there is introduction of themes, samplings, different kinds of variables and main findings. The work offers a good understanding to nature of experimental research and useful data for organizing a real experimental study.

Lasivillatehtaan energiatehokkuus

Diplomityön tavoitteena oli tuottaa toimenpidesuunnitelma energiatehokkuuden parantamiseksi sekä tilannekatsaus tehtaan energiankäytöstä Saint-Gobain Raken-nustuotteet Oy:n Hyvinkään lasivillatehtaalla. Diplomityön ensisijaiseksi tutki-mustavoitteeksi asetettiin energiankäytön tehostamisen tutkiminen sekä energian-käytön analysointi ja jatkotoimenpidesuunnitelman laatiminen. Diplomityössä osoitettiin että lämmöntalteenotolla poistoilmasta voidaan saavut-taa 2000 MWh lämpöenergiansäästö. Yhteensä hyödynnettävää lämpöenergiaa selvitettiin syntyvän vuodessa 10 600 MWh. WCM- konseptilla, eli tuotannonte-hostamisohjelmalla pyritään energiankäytön systemaattiseen pienentämiseen. Täs-sä diplomityössä on esitetty energiankäytön tehostamisratkaisuja sekä energiate-hokkuuden liittämistä WCM- konseptiin. Diplomityön tuloksia voidaan hyödyntää järjestelmällisen energiatehokkuuden parantamisohjelman kehittämisessä sekä konkreettisten energiansäästötoimenpiteiden toteuttamisessa.

Waste Management in Commercial Activity: State-of-the-Art and the Potential Innovation in the Urban Areas of Hanoi, Vietnam

As the rapid development of the society as well as the lifestyle, the generation of commercial waste is getting more complicated to control. The situation of packaging waste and food waste – the main fractions of commercial waste in different countries in Europe and Asia is analyzed in order to evaluate and suggest necessary improvements for the existing waste management system in the city of Hanoi, Vietnam. From all waste generation sources of the city, a total amount of approximately 4000 tons of mixed waste is transported to the composting facility and the disposal site, which emits a huge amount of 1,6Mt of GHG emission to the environment. Recycling activity is taking place spontaneously by the informal pickers, leads to the difficulty in managing the whole system and uncertainty of the overall data. With a relative calculation, resulting in only approximately 0,17Mt CO2 equivalent emission, incinerator is suggested to be the solution of the problem with overloaded landfill and raising energy demand within the inhabitants.

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.

Säteilysuojelu käytetyn ydinpolttoaineen kapselointi- ja loppusijoituslaitoksella

Suomen ydinenergialaki vaatii ydinenergian käytössä syntyvän ydinjätteen käsittelyn ja varastoinnin sekä loppusijoittamisen Suomeen. Fortumin ja TVO:n ydinvoimalaitoksissa syntyvä käytetty ydinpolttoaine tullaan kapseloimaan ja loppusijoittamaan Olkiluotoon rakennettavassa kapselointi- ja loppusijoituslaitoksessa. Tämän työn tavoitteena on muodostaa kokonaiskuva kapselointi- ja loppusijoituslaitoksen säteilysuojelusta aikaisemmin tehtyjen selvitysten ja suunnitelmien perusteella. Kapselointilaitoksella käytetty ydinpolttoaine suljetaan kuparikapseleihin, jotka loppusijoitetaan maan alle loppusijoituslaitoksella. Työn aluksi kuvataan loppusijoitusmenetelmä ja kapselointi- ja loppusijoituslaitoksen käyttötoiminta. Tämän jälkeen käsitellään lainsäädäntöä ja viranomaisohjeita, jotka ohjaavat ydinlaitosten säteilysuojelua. Seuraavaksi käsitellään kapselointi- ja loppusijoituslaitoksella olevia säteilylähteitä. Lisäksi työssä käsitellään kapselointi- ja loppusijoituslaitokselle suunniteltua valvonta-aluetta ja sen säteilyolosuhteiden mukaista vyöhykejakoa. Työssä saatiin tulokseksi kokonaiskuva kapselointi- ja loppusijoituslaitoksen säteilysuojelusta. Kokonaiskuvan muodostamisen lisäksi laadittiin alustavia suunnitelmia käyttötoiminnan säteilysuojelun järjestämisestä. Lisäksi laadittiin ehdotuksia valvonta-alueen tarkemmista rajoista loppusijoituslaitoksella sekä havaittiin laitosten säteilysuojeluun liittyviä ongelmia ja esitettiin ratkaisuja niihin. Ongelmaksi osoittautui muun muassa, että kapselointi- ja loppusijoituslaitoksen valvonta-alueiden luonteiden eroa ei ollut huomioitu suunnitelmissa. Lisäksi todettiin, että nykyisin ydinlaitoksilla käytössä oleva valvonta-alueen vyöhykejako ei vastaa kapselointi- ja loppusijoituslaitosten tarpeita. Näihin esitettiin ratkaisuiksi laitosten välille perustettavaa kenkärajaa ja uuden korkeamman säteilyvyöhykkeen käyttöönottoa.

Purification of Hydrocarbon Waste Streams

Purification of hydrocarbon waste streams is needed to recycle valuable hydrocarbon products, reduce hazardous impacts on environment, and save energy. To obtain these goals, research must be focused on the search of effective and feasible purification and re-refining technologies. Hydrocarbon waste streams can contain both deliberately added additives to original product and during operation cycle accumulated undesired contaminants. Compounds may have degenerated or cross-reacted. Thus, the presence of unknown species cause additional challenges for the purification process. Adsorption process is most suitable to reduce impurities to very low concentrations. Main advantages are availability of selective commercial adsorbents and the regeneration option to recycle used separation material. Used hydrocarbon fraction was purified with various separation materials in the experimental part. First screening of suitable materials was done. In the second stage, temperature dependence and adsorption kinetics were studied. Finally, one fixed bed experiment was done with the most suitable material. Additionally, FTIR-measurements of hydrocarbon samples were carried out to develop a model to monitor the concentrations of three target impurities based on spectral data. Adsorption capacities of the tested separation materials were observed to be low to achieve high enough removal efficiencies for target impurities. Based on the obtained data, batch process would be more suitable than a fixed bed process and operation at high temperatures is favorable. Additional pretreatment step is recommended to improve removal efficiency. The FTIR-measurement was proven to be a reliable and fast analysis method for challenging hydrocarbon samples.

Carte d'Afrique dressée pour l'usage du Roy

Nimeke- ja tekijätiedot nimiönkehyksissä

Carte d'Europe dressée pour l'usage du Roy sur les itinéraires anciens et modernes et sur les routiers de mer assujetis aux observations astronomiques

Nimeke- ja tekijätiedot nimiönkehyksissä