983 resultados para Waste heat utilization


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The utilization of organic wastes represents an alternative to recover degraded pasture. The experiment aimed to assess the changes caused by the provision of different organic waste (poultry litter, turkey litter and pig manure) in a medium-textured Oxisol in Brazilian Savanna under degraded pasture. It was applied different doses of waste compared to the use of mineral fertilizers and organic mineral and evaluated the effect on soil parameters (pH, organic matter, phosphorus and potassium) and leaf of Brachiariadecumbens (crude protein, phosphorus and dry mass production). It was observed that application of organic waste did not increase the level of soil organic matter and pH in the surface layer, and the application of turkey litter caused acidification at depths of 0.20-0.40 m and 0.40-0.60 m. There was an increase in P and K in the soil with the application of poultry litter and swine manure. All organic wastes increased the productivity of dry matter and crude protein and phosphorus. The recycling of nutrients via the application of organic waste allows efficiency of most parameters similar to those observed with the use of mineral sources, contributing to improving the nutritional status of soil-plantsystem.

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Aiming to evaluate the use of sugarcane industry waste such as byproducts from vinasse concentration process, it was assessed the organomineral fertilizer BIOFOM (concentrated vinasse, filter cake, boiler ash, soot from chimneys and supplemented with mineral fertilizers). The study included characterization and agronomic potential analysis of a test plant (corn), by noting the differences between mineral fertilizers and BIOFOM fertilization until 45 days after sowing. The technology traditionally used to produce BIOFOM was based on vinasse evaporation with high heat transfer coefficients. It was observed that the technology, which can be formulated according to the needs of any crop, could be used in many cases as mineral fertilizer. Therefore, the use of this organomineral fertilizer reduces waste generation of sugarcane industry.

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Tutkimuksen tavoitteena oli kartoittaa alueellisen jäteyhtiön Kymenlaakson Jäte Oy:n mahdollisuuksia rakeistaa ja termisesti kuivata mekaanisesti kuivattua mädätysjäännöstä sekä mahdollisuuksia toimittaa termisesti kuivattua materiaalia energiahyötykäyttöön. Tutkimuksessa selvitettiin myös kokemuksia lattialämmityksen käyttämisestä mädätysjäännöksen kuivaukseen. Tutkimuksessa perehdyttiin erilaisiin rakeistus- ja kuivausmenetelmiin sekä termisen kuivurin valintaan vaikuttaviin asioihin. Kuvaukset perustuvat kirjallisuudesta ja internetistä saatuihin tietoihin. Tekniikkakuvausten pohjalta lähdettiin kyselemään tarjouksia termisiä kuivauslaitteistoja myyviltä yrityksiltä. Tarjoukset pyydettiin kuiva-ainepitoisuuden muutokselle 30 %:sta 90 %:iin ja oletettiin, että kuivaukseen on käytettävissä lämpöä viideltä kaatopaikkakaasua käyttävältä mikroturbiinilta. Tutkimuksen aikana saatiin tarjous kuudelta yritykseltä. Saadut tarjoukset esiteltiin tiivistetysti raportissa ja kokonaisuudessaan ne sisällytettiin Kymenlaakson Jäte Oy:n laajempaan raporttiin, joka ei ole julkinen. Yritykset antoivat hyvin erilaisia tietoja siitä, mitä tarjoukseen sisältyy, joten tarjoukset eivät olleet suoraan vertailukelpoisia. Tarjouksista myös havaittiin, että jos Mäkikylän biokaasulaitokselta vastaanotettaisiin enimmäismäärä (19 500 t/a) mädätysjäännöstä, mikroturbiineilta saatava lämpömäärä ei riittäisi kuivaamaan kaikkea mädätysjäännöstä 90 % kuiva-ainepitoisuuteen. Tutkimuksen aikana huomattiin myös, että sitovan tarjouksen saamiseksi mädätysjäännös tulee toimittaa testattavaksi, jolloin saadaan vahvistus kuivausmenetelmän soveltuvuudesta kyseiselle materiaalille. Tutkimuksessa selvitettiin myös, minkälaisia kokemuksia löytyy lattialämmityksen käyttämisestä kuivaukseen niin Suomesta kuin maailmalta ja voiko menetelmää käyttää mädätysjäännöksen kuivaukseen. Kyseistä menetelmää on käytetty tehostamaan aurinkokuivausta, joten tutkimuksen aikana perehdyttiin erityisesti aurinkokuivaukseen liittyviin tieteellisiin artikkeleihin. Lattialämmityksen käytöstä löytyi niin heikkouksia kuin vahvuuksia. Suomessa aurinkokuivauksen ja lattialämmityksen yhdistelmä ei ole kuitenkaan päätynyt laajaan käyttöön ja syynä voidaan nähdä muun muassa kylmät ja pimeät vuodenajat sekä suuri pinta-alan tarve. Tutkimusraportissa selvitettiin lisäksi polttolaitosten edustajien kiinnostusta ja rajoituksia ottaa vastaan termisesti kuivattua mädätysjäännöstä. Tutkimuksen aikana otettiin yhteyttä alle 100 km etäisyydellä Kymenlaakson Jäte Oy:stä sijaitsevien jätteenpolttoluvan omaavien yritysten edustajiin. Saatuja vastauksia käsiteltiin tiivistetysti raportissa ja vastaukset sisällytettiin kokonaisuudessaan Kymenlaakson Jäte Oy:n laajempaan raporttiin, joka ei ole julkinen. Puhelinhaastattelujen pohjalta nähtiin, että yrityksillä on kiinnostusta materiaalia kohtaan, mutta samalla vastauksiin vaikuttavat mädätysjäännöksen analyysitulokset. Poltto-ominaisuuksiin liittyvät analyysit tullaan toteuttamaan vuoden 2012 aikana. Laitoksilla oli myös vaihtelevia rajoituksia materiaalia kohtaan, mutta analyysituloksista riippuen materiaalia voidaan hyödyntää energiana tuhansia tai jopa kymmeniä tuhansia tonneja vuodessa alle 100 km etäisyydellä Kymenlaakson Jäte Oy:stä.

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The aim of this report is to describe the current status of the waste-to-energy chain in the province of Northern Savonia in Finland. This work is part of the Baltic Sea Region Programme project Remowe-Regional Mobilizing of Sustainable Waste-to-Energy Production (2009-2012). Partnering regions across Baltic Sea countries have parallelly investigated the current status, bottle-necks and needs for development in their regions. Information about the current status is crucial for the further work within the Remowe project, e.g. in investigating the possible future status in target regions. Ultimate result from the Northern Savonia point of view will be a regional model which utilizes all available information and facilitates decision-making concerning energy utilization of waste. The report contains information on among others: - waste management system (sources, amounts, infrastructure) - energy system (use, supply, infrastructure) - administrative structure and legislation - actors and stakeholders in the waste-to-energy field, including interest and development ideas The current status of the regions will be compared in a separate Remowe report, with the focus on finding best practices that could be transferred among the regions. In this report, the current status has been defined as 2006-2009. In 2009, the municipal waste amount per capita was 479 kg/inhabitant in Finland. Industrial waste amounted 3550 kg/inhabitant, respectively. The potential bioenergy from biodegradable waste amounts 1 MWh/inhabitant in Northern Savonia. This figure includes animal manure, crops that would be suitable for energy use, sludge from municipal sewage treatment plants and separately collected biowaste. A key strategy influencing also to Remowe work is the waste plan for Eastern Finland. Currently there operate two digestion plants in Northern Savonia: Lehtoniemi municipal sewage treatment sludge digestion plant of Kuopion Vesi and the farm-scale research biogas plant of Agrifood Research Finland in Maaninka. Moreover, landfill gas is collected to energy use from Heinälamminrinne waste management centre and Silmäsuo closed landfill site, both belonging to Jätekukko Oy. Currently there is no thermal utilization of waste in Northern Savonia region. However, Jätekukko Oy is pretreating mixed waste and delivering refuse derived fuel (RDF) to Southern Finland to combustion. There is a strong willingness among seven regional waste management companies in Eastern Finland to build a waste incineration plant to Riikinneva waste management centre near city of Varkaus. The plant would use circulating fluidized bed (CFB) boiler. This would been a clear boost in waste-to-energy utilization in Northern Savonia and in many surrounding regions.

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Forest biomass represents a geographically distributed feedstock, and geographical location affects the greenhouse gas (GHG) performance of a given forest-bioenergy system in several ways. For example, biomass availability, forest operations, transportation possibilities and the distances involved, biomass end-use possibilities, fossil reference systems, and forest carbon balances all depend to some extent on location. The overall objective of this thesis was to assess the GHG emissions derived from supply and energy-utilization chains of forest biomass in Finland, with a specific focus on the effect of location in relation to forest biomass’s availability and the transportation possibilities. Biomass availability and transportation-network assessments were conducted through utilization of geographical information system methods, and the GHG emissions were assessed by means of lifecycle assessment. The thesis is based on four papers in which forest biomass supply on industrial scale was assessed. The feedstocks assessed in this thesis include harvesting residues, smalldiameter energy wood and stumps. The principal implication of the findings in this thesis is that in Finland, the location and availability of biomass in the proximity of a given energyutilization or energy-conversion plant is not a decisive factor in supply-chain GHG emissions or the possible GHG savings to be achieved with forest-biomass energy use. Therefore, for the greatest GHG reductions with limited forest-biomass resources, energy utilization of forest biomass in Finland should be directed to the locations where most GHG savings are achieved through replacement of fossil fuels. Furthermore, one should prioritize the types of forest biomass with the lowest direct supply-chain GHG emissions (e.g., from transport and comminution) and the lowest indirect ones (in particular, soil carbon-stock losses), regardless of location. In this respect, the best combination is to use harvesting residues in combined heat and power production, replacing peat or coal.

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The objective of the present work is the experimental determination of pressure drop coefficients (loss coefficients) for elliptic and circular sections in one, two and three-row arrangements of plate fin and tube heat exchangers. The experiments permitted to correlate the dimensionless loss coefficient with the flow Reynolds number in the rectangular channel formed by the plate fins. The experimental technique consisted of the measurement of the longitudinal pressure distribution along the flow channel, for several values of air mass flow rate. The total number of data runs, each one characterized by the flow Reynolds number, was 216. The present geometry is used in compact heat exchangers for air conditioning systems, heaters, radiators, and others. Also, it is verified the influence of the utilization of elliptic tubes, instead of circular ones, in the pressure drop. The measurements were performed for Reynolds numbers ranging from 200 to 1900.

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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.

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Operation of pulp and paper mills generates waste including wastewater treatment sludge and deinking sludge. Both sludge types are generated in large amounts and are mainly disposed of in landfills in the Leningrad Region resulting in environmental degradation. The thesis was aimed at seeking new sustainable ways of sludge utilization. Two paper mills operating in the Leningrad Region and landfilling their sludge were identified: “SCA Hygiene Products Russia” and “Knauf”. The former generates 150 t/day of deinking sludge, the latter – 145 t/day of secondary sludge. Chemical analyses of deinking sludge were performed to assess applicability of sludge in construction materials production processes. Higher heating value on dry basis of both sludge types was determined to evaluate energy potential of sludge generated in the Leningrad Region. Total energy output from sludge incineration was calculated. Deinking sludge could be utilized in the production process of “LSR-Cement” or “Slantsy Cement Plant Cesla” factories, and “Pobeda” and “Nikolsky” brick mills without exceeding current sludge management costs.

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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.

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More discussion is required on how and which types of biomass should be used to achieve a significant reduction in the carbon load released into the atmosphere in the short term. The energy sector is one of the largest greenhouse gas (GHG) emitters and thus its role in climate change mitigation is important. Replacing fossil fuels with biomass has been a simple way to reduce carbon emissions because the carbon bonded to biomass is considered as carbon neutral. With this in mind, this thesis has the following objectives: (1) to study the significance of the different GHG emission sources related to energy production from peat and biomass, (2) to explore opportunities to develop more climate friendly biomass energy options and (3) to discuss the importance of biogenic emissions of biomass systems. The discussion on biogenic carbon and other GHG emissions comprises four case studies of which two consider peat utilization, one forest biomass and one cultivated biomasses. Various different biomass types (peat, pine logs and forest residues, palm oil, rapeseed oil and jatropha oil) are used as examples to demonstrate the importance of biogenic carbon to life cycle GHG emissions. The biogenic carbon emissions of biomass are defined as the difference in the carbon stock between the utilization and the non-utilization scenarios of biomass. Forestry-drained peatlands were studied by using the high emission values of the peatland types in question to discuss the emission reduction potential of the peatlands. The results are presented in terms of global warming potential (GWP) values. Based on the results, the climate impact of the peat production can be reduced by selecting high-emission-level peatlands for peat production. The comparison of the two different types of forest biomass in integrated ethanol production in pulp mill shows that the type of forest biomass impacts the biogenic carbon emissions of biofuel production. The assessment of cultivated biomasses demonstrates that several selections made in the production chain significantly affect the GHG emissions of biofuels. The emissions caused by biofuel can exceed the emissions from fossil-based fuels in the short term if biomass is in part consumed in the process itself and does not end up in the final product. Including biogenic carbon and other land use carbon emissions into the carbon footprint calculations of biofuel reveals the importance of the time frame and of the efficiency of biomass carbon content utilization. As regards the climate impact of biomass energy use, the net impact on carbon stocks (in organic matter of soils and biomass), compared to the impact of the replaced energy source, is the key issue. Promoting renewable biomass regardless of biogenic GHG emissions can increase GHG emissions in the short term and also possibly in the long term.

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The aim of this thesis is to study whether the use of biomethane as a transportation fuel is reasonable from climate change perspective. In order to identify potentials and challenges for the reduction of greenhouse gas (GHG) emissions, this dissertation focuses on GHG emission comparisons, on feasibility studies and on the effects of various calculation methodologies. The GHG emissions calculations are carried out by using life cycle assessment (LCA) methodologies. The aim of these LCA studies is to figure out the key parameters affecting the GHG emission saving potential of biomethane production and use and to give recommendations related to methodological choices. The feasibility studies are also carried out from the life cycle perspective by dividing the biomethane production chain for various operators along the life cycle of biomethane in order to recognize economic bottlenecks. Biomethane use in the transportation sector leads to GHG emission reductions compared to fossil transportation fuels in most cases. In addition, electricity and heat production from landfill gas, biogas or biomethane leads to GHG reductions as well. Electricity production for electric vehicles is also a potential route to direct biogas or biomethane energy to transportation sector. However, various factors along the life cycle of biomethane affect the GHG reduction potentials. Furthermore, the methodological selections have significant effects on the results. From economic perspective, there are factors related to different operators along the life cycle of biomethane, which are not encouraging biomethane use in the transportation sector. To minimize the greenhouse gas emissions from the life cycle of biomethane, waste feedstock should be preferred. In addition, energy consumption, methane leakages, digestate utilization and the current use of feedstock or biogas are also key factors. To increase the use of biomethane in the transportation sector, political steering is needed to improve the feasibility for the operators. From methodological perspective, it is important to recognize the aim of the life cycle assessment study. The life cycle assessment studies can be divided into two categories: 1.) To produce average GHG information of biomethane to evaluate the acceptability of biomethane use compared to fossil transportation fuels. 2.) To produce GHG information of biomethane related to actual decision-making situations. This helps to figure out the actual GHG emission changes in cases when feedstock, biogas or biomethane are already in other use. For example directing biogas from electricity production to transportation use does not necessarily lead to additional GHG emission reductions. The use of biomethane seems to have a lot of potential for the reduction of greenhouse gas emissions as a transportation fuel. However, there are various aspects related to production processes, to the current use of feedstock or biogas and to the feasibility that have to be taken into account.

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Waste incineration is becoming increasingly widespread method of waste disposal in China. Incineration plants mostly use grate and circular fluidized bed (CFB) technology. Waste combustion in cement production is also beginning to gradually increase. However, Chinese waste composition is causing problems for the energy utilization. Mechanical waste pre-treatment optimizes the combustion process and facilitates the energy recovery. The objective of this study is to identify how Western waste pre-treatment manufacturer could operate in Chinese markets. Chinese waste management industry is reviewed via PESTEL analysis. The current state and future predictions of grate and CFB incineration as well as cement manufacturing are monitored. Grate combustion, which requires lesser waste pre-treatment, is becoming more common at the expense of CFB incineration in China. The most promising future for waste treatment is in cement production industry. Waste treatment equipment manufacturer should try to create pilot projects with biggest cement producers with a view of growing co-operation in the future.

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The growing population in cities increases the energy demand and affects the environment by increasing carbon emissions. Information and communications technology solutions which enable energy optimization are needed to address this growing energy demand in cities and to reduce carbon emissions. District heating systems optimize the energy production by reusing waste energy with combined heat and power plants. Forecasting the heat load demand in residential buildings assists in optimizing energy production and consumption in a district heating system. However, the presence of a large number of factors such as weather forecast, district heating operational parameters and user behavioural parameters, make heat load forecasting a challenging task. This thesis proposes a probabilistic machine learning model using a Naive Bayes classifier, to forecast the hourly heat load demand for three residential buildings in the city of Skellefteå, Sweden over a period of winter and spring seasons. The district heating data collected from the sensors equipped at the residential buildings in Skellefteå, is utilized to build the Bayesian network to forecast the heat load demand for horizons of 1, 2, 3, 6 and 24 hours. The proposed model is validated by using four cases to study the influence of various parameters on the heat load forecast by carrying out trace driven analysis in Weka and GeNIe. Results show that current heat load consumption and outdoor temperature forecast are the two parameters with most influence on the heat load forecast. The proposed model achieves average accuracies of 81.23 % and 76.74 % for a forecast horizon of 1 hour in the three buildings for winter and spring seasons respectively. The model also achieves an average accuracy of 77.97 % for three buildings across both seasons for the forecast horizon of 1 hour by utilizing only 10 % of the training data. The results indicate that even a simple model like Naive Bayes classifier can forecast the heat load demand by utilizing less training data.

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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.

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Brazil is considered one of the largest producers and consumers of tropical fruits. Green coconut (Cocos nucifera L.) stands out not only for its production and consumption, but also for the high amount of waste produced by coconut water industry and in natura consumption. Therefore, there is a need for utilization of this by-product. This study aims to study the adsorption isotherms of green coconut pulp and determine its isosteric heat of sorption. The adsorption isotherms at temperatures of 30, 40, 50, 60, and 70 °C were analyzed, and they exhibit type III behavior, typical of sugar rich foods. The experimental results of equilibrium moisture content were correlated by models present in the literature. The Guggenheim, Anderson and De Boer (GAB) model proved particularly good overall agreement with the experimental data. The heat of sorption determined from the adsorption isotherms increased with the decrease in moisture content. The heat of sorption is considered as indicative of intermolecular attractive forces between the sorption sites and water vapor, which is an important factor to predict the shelf life of dried products.