Mädätysjäännöksen tuotteistamismahdollisuudet Kymenlaaksossa

Biokaasun tuotantoa ollaan selvästi lisäämässä Suomessa. Biokaasutuksen kokonaishyödyn kannalta on olennaista, että mädätyksen lopputuote eli mädätysjäännös saadaan lannoitekäyttöön. Tämän työn tavoitteena oli selvittää Kymenlaakson Jäte Oy:n mahdollisuuksia tuotteis-taa Kymen Bioenergia Oy:n yhteismädätyslaitoksen mädätysjäännöstä. Työssä keskityttiin hyötykäyttövaihtoehdoista lannoitekäyttöön maanviljelyssä sekä tilanteeseen jossa mädätyslaitos käsittelee sekä puhdistamolietettä että biojätettä ja mädätysjäännös kuivataan mekaanisesti. Mekaanisesti kuivatun mädätysjäännöksen ensisijaiset tuotteistamisvaihtoehdot maanviljelyyn ovat joko jäännös sellaisenaan tai termisesti kuivattuna ja rakeistettuna, eli kuivarakeena. Mäkikylän laitoksen mädätysjäännöksen arvo peltolannoitteena on syyskuun 2010 keinolannoit-teiden hintaan vertaamalla sellaisenaan noin 1–20 €/t ja kuivarakeena noin 2–60 €/t. Arvo riippuu siitä, miten tuotteiden typpeä ja fosforia huomioidaan kasveille käyttökelpoiseksi. Täl-lä hetkellä käyttökelpoisin tapa on ympäristötuen puhdistamolietetuotteita koskevien ehtojen mukaisesti ottaa huomioon vesiliukoinen typpi ja 40 % kokonaisfosforista. Tällöin mädätys-jäännöksen arvo on noin 6 €/t ja kuivarakeen n. 18 €/t. Käytön kannalta kuivarae on helpompi vaihtoehto ja alueen viljelijät ovat heille tehdyn kyselyn mukaan varsin kiinnostuneita kuivarakeesta lannoitteena. Muista tuotteistusvaihtoehdoista termisesti kuivaamalla mädätysjäännöksen tehollinen lämpö-arvo saapumistilassa on noin 10 MJ/kg. Vastaava arvo jyrsinturpeen kesäkuun 2010 hinnan mukaan on noin 30 €/t. Tuotteen soveltuvuus polttoon tulee silti varmistaa. Termisesti kuiva-tulla mädätysjäännöksellä on tuotteistamismahdollisuuksia hieman laajemmin kuin kompostoidulla. Kompostoidun mädätysjäännöksen tuotteistamisen lähtökohta on lähinnä viherrakentaminen. Maanviljelykäyttöä ajatellen mädätysjäännöstä ei välttämättä tarvitse kompostoida.

Potential of energy and nutrient recovery from biodegradable waste by co-treatment in Lithuania

Biodegradable waste quantities in Lithuania and their potential for the co-treatment in renewable energy and organic fertilizer production are investigated. Two scenarios are formulated to study the differences of the amounts of obtainable energy and fertilizers between different ways of utilization. In the first scenario, only digestion is used, and in the second scenario, other materials than straw are digested, and straw and the solid fraction of sewage sludge digestate are combusted. As a result, the amounts of heat and electricity, as well as the fertilizer amounts in the counties are obtained for both scenarios. Based on this study, the share of renewable energy in Lithuania could be doubled by the co-treatment of different biodegradable materials.

ETYK III-vaihe (Tasavallan Presidentin esittämä Suomen puheenvuoro 31.7.1975 = Conference on Security and Co-operation in Europe = main speech of Finland delivered by President Urho Kekkonen July 31, 1975)

Puhe

Photosynthesis and Rubisco kinetics in spring wheat and meadow fescue under conditions of simulated climate change with elevated CO[sub 2] and increased temperatures

Selostus: Kevätvehnän ja nurminadan fotosynteesi ja Rubisco-kinetiikka simuloidun ilmastonmuutoksen eli kohotetun hiilidioksidipitoisuuden ja kohotetun lämpötilan oloissa

Simulation of spring wheat responses to elevated CO‚́‚ and temperature by using CERES-wheat crop model

Selostus: Kohotettujen CO‚́‚:n ja lämpötilan vaikutukset kevätvehnän fenologiseen kehitykseen ja sadontuottomahdollisuuksiin

Effects of rotation period on biomass production and atmospheric CO‚́‚ emissions from broadleaved stands growing on abandoned farmland

Abstract

Naudan lietelannan käsittelymenetelmien taloudellinen vertailu

Maataloudessa syntyvä lanta on arvokas lannoite ja maanparannusaine, jonka käsittelystä aiheutuu sekä kustannuksia että ympäristövaikutuksia. Muita haasteita ovat esimerkiksi lannan mikrobit, lannan levitykseen soveltuvan ajankohdan lyhyys, lannan ravinteiden sovittaminen kasvien tarpeisiin ja lannan ravinteiden määrä suhteessa levityskelpoisen peltoalan määrään. Tutkimuksen tavoitteena oli tunnistaa naudan lietelannan käsittelyketjuihin liittyvät kustannukset ja osoittaa eri käsittelyketjujen kustannusten eroavaisuudet. Tavoitteena oli myös tunnistaa ja osoittaa käsittelyketjujen laadulliset erot. Kustannukset selvitettiin kustannuslaskelmin ja laadulliset erot SWOT-menetelmällä. Tutkimuksen kohteeksi valittiin 6 tilakokoluokkaa ja käsittelyketjuiksi lietelanta-, kompostointi- ja mädätysketju. Tutkimuksessa alhaisimmat kustannukset olivat lietelantaketjulla, jonka kustannukset 25 – 250 naudan tilalla olivat 5 200 – 6 600 €/a ja yksikkökustannukset 1 – 9 €/m3. Mädätysketjun kustannukset vastaavissa tilakokoluokissa olivat noin 33 000 – 50 000 €/a ja yksikkökustannukset 8 – 55 €/m3. Kompostointiketjun kustannukset olivat 35 000 – 143 000 €/a ja yksikkökustannukset 24 – 58 €/m3. Lietelantaketjun edullisuus johtui vähäisistä laite- ja rakennusinvestoinneista ja pienistä työmääristä ja kompostointiketjun kalleus suurista tukiaine- ja investointikustannuksista. Käsittelyketjujen asettaminen paremmuusjärjestykseen oli hankalaa. Työn määrä oli pienin lietelantaketjussa ja toiseksi pienin suurilla tiloilla mädätysketjussa. Kompostointiketjulla itse levitykseen kuluva aika oli pienin. Ravinteiden osalta mädätysketju oli parhain ja kompostointiketju huonoin. Ympäristövaikutuksiltaan ja hajuhaitoiltaan kompostointi- ja mädätysketju olivat parhaimmat. Mikrobien osalta parhain oli kompostointiketju.

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.

The fleet of the Finska Ångfartygs Aktiebolaget (Finland Steamship Co. Ltd), Helsingfors - [Cover]

Julkaisusta puuttuu s/s Oihonnan pohjapiirustus, sen paikalla on s/s Wellamon pohjapiirustus toiseen kertaan.

Anaerobic treatment of deinking pulp plant effluents

Anaerobic treatment as a first biological stage in wastewater treatment is nowadays a well-established technology in recycled paper processing mills using closed water circuits. Today further developed high-rate processes and especially high-tower reactors are also able to handle lower organic loads and become therefore feasible for deinking pulp plant effluents. The interest in the anaerobic method is based on a positive energy balance in form of biogas production and low biomass yield from the process. The anaerobic treatment method was researched and its suitability for the deinking pulp plant effluents was tested experimentally at Stora Enso Maxau mill. In the theory, the deinking pulp process is introduced and the effluents from the deinking process are characterized. The anaerobic treatment is brought up in depth in terms of its use for the deinking effluents, and different kind of reactor types are presented. In addition, other wastewater treatment methods are shortly introduced with the focus on tertiary treatment. Static biodegradability tests were carried out for the wastewaters both anaerobically and aerobically. Based on the results, the deinking effluents can be degraded anaerobically, and inhibition to the methanogenic bacteria was not noticed. In the aerobic static test a good performance of the existing wastewater treatment plant at Maxau mill was proved. Later on pilot trials with sequential anaerobic-aerobic treatment were carried out for the deinking effluents. The anaerobic reactor used was a so called internal circulation reactor. The results confirmed that the combination of the anaerobic treatment and the aerobic activated sludge process is a suitable method for deinking wastewaters with a COD reduction as good as with a two stage aerobic method. When combined with the outstanding quality of the produced biogas and the cost savings acquired from the lower sludge production, the anaerobic treatment was found to be an especially favorable treatment method.

Challenges in co-operation with Logistics Service Providers

Kiristyvä kilpailu ja korkean teknologian alalle tyypillisten nopeiden suhdannevaihteluiden tuomat haasteet ajavat yrityksiä etsimään uusia kehityskohteita ja kustannussäästöjä. Ydinosaamisen ulkopuolelle kuuluvan osa-alueen ulkoistamisella yritykset hakevat tehokkuutta ja kustannussäästöjä eri toimintoihinsa. Tässä työssä selvitetään tutkittavan yrityksen toteutuneita ulkoistamisprojekteja, niiden tuomia etuja ja haittoja. Tutkimuksen teoriaosuudessa käsitellään yleisesti ulkoistamiseen liittyviä asioita, sekä uppoudutaan erityisesti logistiikan ulkoistamisen tuomiin mahdollisuuksiin ja haasteisiin. Empiirinen osuus käsittää prosessikuvaukset tutkittavan yrityksen logistisista toiminnoista sekä yrityksen toteutuneista ulkoistamisprojekteista. Vertailut -kappaleessa pohditaan mitä logistiikan ulkoistaminen on tarkoittanut sekä kustannus että operatiivisessa mielessä.

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.