Aluminium fouling and its impact on activated carbon based dioxin and furan removal in a wet scrubber at a co-incineration plant

Dioxins and furans, PCDD/Fs, are highly toxic substances formed in post combustion zones in furnaces. PCDD/F emissions are regulated by a waste incineration directive which relates also to co-incineration plants. Several observations of dioxin and furan enhancements in wet scrub- bers have been reported previously. This is thought to be due to the so-called "memory effect" which occurs when dioxins and furans absorb into plastic material in scrubbers and desorb when ambient circumstances alter significantly. At the co-incineration plant involved, dioxins and furans are controlled with a wet scrubber, the tower packing of which is made of plastic in which activated carbon particles are dispersed. This should avoid the memory effect and act as a dioxin and furan sink since dioxins and furans are absorbed irreversibly into the packing ma- terial. In this case, the tower packing in the scrubber is covered with a white layer that has been found to be mainly aluminium. The aim of this thesis was to determine the aluminium balance and the dioxin and furan behaviour in the scrubber and, thus, the impacts that the foul- ing has on dioxin and furan removal. The source of aluminium, reasons for fouling and further actions to minimize its impacts on dioxin and furan removal were also to be discovered. Measurements in various media around the scrubber and in fuels were made and a profile analysis of PCDD/F and mass balance calculations were carried out. PCDD/F content de- creased in the scrubber. The reduced PCDD/F was not discharged into scrubbing water. The removal mechanism seems to work in spite of the fouling, at least with low PCDD/F loads. Most of the PCDD/F in excess water originates from the Kymijoki River which is used as feeding water in the scrubber. Fouling turned out to consist mainly of aluminium hydroxides. Sludge combusted in the furnace was found to be a significant source of aluminium. Ways to minimize the fouling would be adjustment of pH to a proper lever, installation of a mechanical filter to catch the loose material from the scrubbing water and affecting the aluminium content of the sludge.

Metsähakkeen jalostusarvon nostaminen eri kuivausmenetelmillä

The thesis was made for Hyötypaperi Oy. To the business activity of the company belongs the recycling of materials and carry out for re-use and the manufacture of solid biofuels and solid recovered fuels. Hyötypaperi Oy delivers forest chips to its partner incineration plants by day and night though the year. The value of the forest chips is based on its percentage of dry material. It is important to dry forest chips well before its storage in piles and delivering to incineration plants. In the thesis was examed the increasing of the degree of refinement of forest chips by different drying methods. In the thesis was examined four different drying methods of the forest chips. The methods were field-, plate-, platform- and channel drying. In the channel drying was used a mechanical blower and the other drying methods were based on the weather conditions. By all drying methods were made test dryings during the summer 2007. In the thesis was examined also the economical profitableness of the field- and channel drying. The last examination in the thesis was measuring of the forest chips’s humidity by humidity measuring equipment of sawn timber during November 2007. The field drying on the surface of asphalt is the only method of drying, which is used by Hyötypaperi Oy in its own production. There do not exist earlier properly examined facts of any drying methods of forest chips, because the drying of forest chips is a new branch. By field- and platform drying achieved lower humidity of forest chips than by plate drying. The object by using the humidity measuring equipment was to be informed of the humidity of forest chips. At present the humidity will find out after 24 hours when the sample of humidity quantity has been dried in the oven. The Lappeenranta University of Technology had the humidity measuring equipment of sawn timber. The values of humidity measured by the equipment from the sample of forest chips were 2 – 9 percent lower than the real values of humidity specified by drying in oven.

Immunological aspects of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (copd) is a major cause of illness and death throughout the world. It affects about 10% of the general population, but its prevalence among heavy smokers can reach 50%.COPD is the fourth leading cause of death in most industrialized countries, and it is projected to be the third leading cause of death worldwide by 2020. Tobacco smoking is the primary risk factor for the development of COPD, but other factors, such as burning biomass fuels for cooking and heating, are important causes of COPD in many developing countries....

Fiscal sustainability and fiscal shocks in a dollarized and oil-exporting country: Ecuador

This paper investigates the fiscal sustainability of an emerging, dollarized, oil-exporting country: Ecuador. A cointegrated VAR approach is adopted in testing, first, if the intertemporal budget constraint is satisfied in Ecuador and, second, in identifying the permanent and transitory shocks that affect a fiscal policy characterized by inertia and a heavy dependence on oil revenues. Following confirmation that the debt-GDP ratio does not place the Ecuadorian budget under any pressure, we reformulate the model and identify two forces that push the fiscal system out of equilibrium, namely, economic activity and oil revenues implemented in the government budget. We argue that Ecuador needs to recover control of its monetary policy and to promote the diversification of its economy in order that non-oil tax revenues can replace oil revenues as a pushing force. Finally, we calculate quarterly elasticities of tax revenues with respect to Ecuador’s GDP and that of eight Eurozone countries. We illustrate graphically how the Eurozone countries with low positive or high negative elasticities’ levels suffer debt problems after the crisis. This finding emphasizes the pressing need for Ecuador to strengthen the connection between its tax revenues and output, and also suggests that the convergence of these elasticities in the Eurozone might contribute to the success of an eventually future fiscal union.

One more lie: the Monday effect in Spain’s retail petrol market

Empirical evidence drawn from the economic literature points to a low level of competition in the retail petrol market. Similar evidence can be found for the Spanish market. In fact, both Spain’s antitrust authority -Comisión Nacional de la Competencia- and its energy regulator -Comisión Nacional de la Energía- have recently initiated disciplinary proceedings against the majors on the grounds of suspected price manipulation in the retail petrol market. They are accused of cutting retail prices on Mondays so as to distort the rank position of Spain in European Union statistics in a practice that has received the name of the Monday effect. Here, we analyze this effect by constructing a database that includes daily retail prices for all petrol stations in Spain in the period 2009-2012, and a more detailed database for the city of Barcelona in 2013. Our estimations confirm that: 1- in 2011 and 2012 prices fell on Mondays at retailers branded by majors; 2- prices were unchanged at stations in our two control groups; 3- prices were also seen to fall when a more detailed analysis was conducted, and this price cut was also found in 2013. In short, one more indicator of collusion in this sector and … one more lie.

Mergers and difference-in-difference estimator : why firms do not increase prices?

Difference-in-Difference (DiD) methods are being increasingly used to analyze the impact of mergers on pricing and other market equilibrium outcomes. Using evidence from an exogenous merger between two retail gasoline companies in a specific market in Spain, this paper shows how concentration did not lead to a price increase. In fact, the conjectural variation model concludes that the existence of a collusive agreement before and after the merger accounts for this result, rather than the existence of efficient gains. This result may explain empirical evidence reported in the literature according to which mergers between firms do not have significant effects on prices.

Energiansiirtoketjun energiatehokkuus

Tämän työn tavoitteena oli tarkastella energiansiirtoketjun kokonaisenergiatehokkuutta, alkaen polttoaineesta ja päättyen sähköenergian loppukäyttäjään. Tarkasteltava energiansiirtoketju alkaa polttoaineen tuotannosta ja siirrosta. Tämän jälkeen tulee sähköenergian tuottaminen, siirtäminen, jakelu ja loppukäyttö. Sähköntuotannon osalta tarkasteltiin myös vesivoimaa ja tuulivoimaa, jolloin energiansiirtoketjusta jää polttoaineen tuotannon ja siirron häviöt pois. Työn pääpaino kohdistui sähköenergian tuotannon, siirron, jakelun ja loppukäytön energiatehokkuuksien tarkastelemiseen. Työssä selvitettiin myös tulevaisuuden näkymiä, miten hyötysuhteita saataisiin parannettua eri osa-alueilla uusilla tekniikoilla ja käyttötottumuksilla. Loppukäyttäjä saa polttoaineen energiasta hyödyksi noin neljänneksen. Suurimmat häviöt syntyvät sähköenergian tuotannossa, lukuun ottamatta vesivoimalaitoksia, joiden hyötysuhde on erittäin korkea.

Vertical relations and local competition : an empirical approach

The analysis of vertical industry relations forms an essential element in the field of industrial organization. This paper tests hypotheses derived from transaction cost theory and the principal-agent problem in Chile’s petrol market. It shows that local competition plays an important role in the choice of a disintegrated vertical structure, and that low levels of service investment have the same effect. Conversely, the number of own-brand outlets and a high level of investment in services reduce the probability of disintegration. The paper demonstrates that vertical disintegration has a null effect on wholesale petrol prices and a positive effect on retail petrol prices of between 1.6 and 7 per cent, depending on fuel type.

Symmetric or asymmetric gasoline prices? A meta-analysis approach

The analysis of price asymmetries in the gasoline market is one of the most studied in the energy economics literature. Nevertheless, the great variability of results makes it very difficult to extract conclusive results on the existence or not of asymmetries. This paper shows through a meta-analysis approach how the industry segment analysed, the quality and quantity of data, the estimator and the model used may explain this heterogeneity of results.

Chemistry and light - part 2: light and energy

The conversion of solar energy into more useful forms of energy, such as chemical fuels or electricity, is one of the central problems facing modern science. Progress in photochemistry and chemical synthesis has led to a point where light energy conversion by means of artificial molecular devices can be rationally attempted. In this article, a general approach towards this challenging goal is presented.

Efeito do campo magnético na precipitação de parafinas

In the oil industry, the paraffination phenomenon is a major problem during oil production, displacement and treatment. Paraffin deposition in subsea flowlines, surface equipment, production string or even in the reservoir, can cause significant and increasing oil losses. To minimize paraffin precipitation, the application of magnetic field in the petroleum path has been suggested based on empiric studies. In this study, we assembled a labscale magnetic conditioner to determine the influence of magnetic field on the physical-chemical properties of two fluids : oil and a paraffin mixture. We observed that magnetic field reduce sample aparent viscosity due to crystal morphology alteration.

Troca iônica no estado sólido de európio3+ em zeólita Y: influência do tempo de reação

Rare earth elements supported in zeolites are the most important catalysts in the fluid cracking of petroleum. The solid state ion exchange of Eu3+ in Y zeolite was investigated. First of all, the hydrated EuCl3 was well mixed in a ball mill and was then heated at 300ºC for different times. The quantitative determination of Eu3+ showed that the degree of ion exchange depends on the reaction time at constant temperature, being ~95% in 4 h. The X-ray study showed that the crystallinity of the zeolite is little affected by the exchange procedure. The study of spectroscopic properties of Eu3+, emission spectra and lifetime, give information about the migration and position of the ion in the zeolite cages.

IEA Bioenergy Task 40 “Sustainable International Bioenergy Trade: Securing supply and demand” Country report of Finland 2008

This study considered the current situation of biofuels markets in Finland. The fact that industry consumes more than half of the total primary energy, widely applied combined heat and power production and a high share of solid biomass fuels in the total energy consumption are specific to the Finnish energy system. Wood is the most important source of bioenergy in Finland, representing 21% of the total energy consumption in 2006. Almost 80% of the wood-based energy is recovered from industrial by-products and residues. Finland has commitment itself to maintaining its greenhouse gas emissions at the 1990 level, at the highest, during the period 2008–2012. The energy and climate policy carried out in recent years has been based on the National Energy and Climate introduced in 2005. The Finnish energy policy aims to achieve the target, and a variety of measures are taken to promote the use of renewable energy sources and especially wood fuels. In 2007, the government started to prepare a new long-term (up to the year 2050) climate and energy strategy that will meet EU’s new targets for the reduction of green house gas emissions and the promotion of renewable energy sources. The new strategy will be introduced during 2008. The international biofuels trade has a substantial importance for the utilisation of bioenergy in Finland. In 2006, the total international trading of solid and liquid biofuels was approximately 64 PJ of which import was 61 PJ. Most of the import is indirect and takes place within the forest industry’s raw wood imports. In 2006, as much as 24% of wood energy was based on foreignorigin wood. Wood pellets and tall oil form the majority of export streams of biofuels. The indirect import of wood fuels increased almost 10% in 2004–2006, while the direct trade of solid and liquid biofuels has been almost constant.

Radiative Heat Transfer in Boiler Furnaces

Better models are needed for radiative heat transfer in boiler furnaces. If the process is known better, combustion in the furnace can be optimized to produce low emissions. It makes the process to be environmental friendly. Furthermore, if there is a better model of the furnace it can more fully explain what is happening inside the furnace. Using of the model one can quickly and easily analyze how it operates with bio fuels, moist fuels or difficult fuels and improve the operation. Models helps with better estimation of furnace dimensions and result in more accurate understanding of operation. Key component lacking in these models is radiative heat transfer in particle laden gases. If there are no particles than radiative heat transfer can be calculated approximately. There are two problems with current models when used with flow modeling. The first one is a need to account for a particle laden gas and the second one is an absence of a fast algorithm. Fast calculation is needed if radiative heat transfer calculation is done for a large CDF model. Computations slow down if time is required for calculating radiative properties over and over again. This thesis presents a band model for radiative heat transfer in boiler furnaces. Advantage is a quickness of calculation and account of particles in the process.

Metsäpolttoaineiden vesitiekuljetus proomukalustolla

Metsäpolttoaineiden käyttö kasvaa lämpö- ja voimalaitoksissa ja mahdollisissa biojalostamoissa. Metsäpolttoaineilla voidaan saavuttaa päästövähennyksiä korvaamalla päästöintensiivisempiä polttoaineita. Metsäpolttoaineen kysynnän kasvu suurkäyttöpaikoilla luo uusia vaatimuksia metsäbiomassan hankintaan. Metsäpolttoaineiden vesitiekuljetuksen sisältämiä logistiikkajärjestelmiä kehittämällä toimitusvarmuutta pystytään parantamaan ja hankintaa laajentamaan kustannustehokkaasti ja ympäristöystävällisesti. Kuljetuskokeilut antoivat uutta tietoa vesitiekuljetuksen sisältämästä hankinnasta. Lastikapasiteetti nykyisen kaltaisessa Eurooppa IIa -suurproomussa vaihtelee 1200 tonnista jopa 1800 tonniin (kosteus 40 %) riippuen tiivistymisestä ja proomun modifiointiasteesta. Metsähakkeen energiatiheys oli suurproomukuljetuksissa keskimäärin 1 MWh/i-m3, joka oli 25 % parempi kuin vertailun hakerekkakuljetuksissa. Vesitiekuljetuksen kustannukset olivat kuljetuskokeiluissa lastauksineen ja purkuineen 0,02 €/MWh/km, ollen noin 20 % ketjun kokonaiskustannuksista. Simuloinnin edullisimpien vesitiekuljetusvaihtoehtojen vaihteluvälin kustannukset olivat vastaavasti 0,013 - 0,026 €/MWh/km. Lastauksen ja purun kustannus oli 0,4 - 0,6 €/MWh ja vesitiekuljetus 0,9 - 2,0 €/MWh (100 km). Ketjun kokonaiskustannukset hakkuutähdehakkeelle vaihtelivat simuloinnin edullisimpien vaihtoehtojen perusteella välillä 10,8 - 12,1 €/MWh (30 km rekka, 100 km proomu). Kuljetusketjujen simuloinnin kustannukset osoittivat proomukuljetusketjun olevan kilpailukykyinen vaihtoehto hakerekkakuljetusketjulle kalustosta ja vuosittaisista käyttötunneista riippuen kuljetusetäisyyden ylittäessä 100 km. Kustannustehokkain ratkaisu vesitiekuljetuksessa saavutettiin pienen aluksen ja suuren kokoluokan proomuyksikön kytkyeellä. Haketus kannattaa toteuttaa ennen proomukuljetuksen osuutta metsähakkeen paremman tiiviyden ja käsiteltävyyden perusteella. Logistiikkajärjestelmiä pitää kehittää tapauskohtaisesti käyttöpaikan tarpeet ja olosuhteet huomioon ottaen. Metsäpolttoaineiden vesitiekuljetuksen sisältämän logistiikan liiketoimintamallien vertailussa arvioitiin vaihtoehtoiset ulkoistetut toimintamallit paremmaksi kuin nykyinen urakointimalli. Tämä mahdollistaa paremman metsähakkeen saatavuuden ja logistiikan tehokkuuden lastausterminaaleissa. Terminaalitoiminnot ja proomukuljetukset lisäävät uusia liiketoimintamahdollisuuksia ja mahdollistavat metsäpolttoaineiden