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Number of results: 57
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Abstract

The article has presented the assumptions underlying the organization of emissions trading of greenhouse gases with a particular emphasis on CO2 emission allowances. Through the analysis of the literature, international activities were undertaken aimed at reducing greenhouse gas emissions into the atmosphere, starting from the First World Climate Conference organized in 1979. The origins and guidelines of the Kyoto Protocol were also given considerable attention. In addition to the description of the key assumptions of the Protocol and its main components, the characteristics of international trade in Kyoto units were also included. The mechanisms involved in international trade and the types of units traded in a detailed manner are described. In the next part of the article, emission trading systems operating in the world are characterized. In the second part of the paper special attention was paid to the conditionings of the European market, i.e. European Emissions Trading System – EU ETS. Historical events were presented that gave rise to the creation of the EU ETS. In the next steps, the types of units that are tradable were described. Furthermore, the trade commodity exchanges on which trade is conducted, the key factors determining the price of individual allowances are also indicated. In the last part of the article, relatively recent issues – the IED Directive and the BAT conclusions have been pointed out. Referring to the applicable regulations, the impact of their implementation on the situation of entities obliged to limit greenhouse gas emissions was analyzed. In the final phase, an attempt was made to assess the impact of IED and BAT to electricity prices.
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Abstract

Coal combustion processes are the main source of mercury emission to the environment in Poland. Mercury is emitted by both power and heating plants using hard and brown coals as well as in households. With an annual mercury emission in Poland at the level of 10 Mg, the households emit 0.6 Mg. In the paper, studies on the mercury release in the coal and biomass combustion process in household boilers were conducted. The mercury release factors were determined for that purpose. For the analyzed samples the mercury release factors ranged from 98.3 to 99.1% for hard coal and from 99.5% to 99.9% for biomass, respectively. Due to the high values of the determined factors, the amount of mercury released into the environment mainly depends on the mercury content in the combusted fuel. In light of the obtained results, the mercury content in the examined hard coals was 6 times higher than in the biomass (dry basis). Taking the calorific value of fuels into account, the difference in mercury content between coal and biomass decreased, but its content in coal was still 4 times higher. The mercury content determined in that way ranged from 0.7 to 1.7 μg/MJ for hard coal and from 0.1 to 0.5 μg/MJ for biomass, respectively. The main opportunity to decrease the mercury emissions from households is offered by the use of fuels with a mercury content that is as low as possible, as well as by a reduction of fuel consumption. The latter could be obtained by the use of modern boilers as well as by the thermo-modernization of buildings. It is also possible to partially reduce mercury emissions by using dust removal devices.
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Abstract

It is contended that, in essence, climate policy is sustainable development policy, given that it postulates the use of renewable resources, and an increase in the effectiveness of use of non-renewable ones. Furthermore, it serves the security of future generations more than present ones; for while unfavourable impacts of climate change are already making their presence felt, truly negative consequences of considerable signifi cance are likely to be more of a matter for the second half of the present century. This is why, in analysing the evolution of the approach to climate policy through the late 20th century and into the 21st, it is also possible to appraise changes in the approach to the sustainable-development concept. This article has therefore sought to offer the author’s analysis of how the approach to sustainable development has evolved, by reference to Poland’s climate policy from 1988 through to 2016. As this is done, an attempt is also made to identify the conditioning that has decided upon and will go on determining the shape of national policy in this domain. Climate policy in Poland has been developing since the early 1990s. At the outset, it was not a source of controversy, with the consequence that the country rather rapidly signed up to and then ratifi ed the Kyoto Protocol to the UN Framework Convention on Climate Change. However, as early as in the late 1990s, reservations began to be expressed, to the effect that actions to protect the climate might pose a threat to Poland’s economy. A key turning point as regards the approach came with the growing dispute over the EU 2020 Climate and Energy Package. It was also at this time that a thesis began to take shape, holding that the goals of climate policy where at best unfavourable and at worst dangerous for Poland. This approach in fact held sway in successive years, leaving this country’s cooperation with the EU over this matter severely hindered. The main reason for this change of approach to climate policy can be considered to lie in the politicisation thereof, and hence the increasing dominance of the short-term interests of the Polish political elite over either the public interest or the security of future generations.
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Abstract

For a very long period of time, Polish waste management was based mainly on landfilling at landfills, which had a negative impact on the surrounding environment. The EU requirements for the Member States have led to a revolution in Polish legislation on waste management and local governments have become responsible for creating local waste management systems that will affect the achievement of EU targets. One of the solutions undertaken by several municipalities is the construction and operation of a municipal waste thermal treatment installation, which not only reduced the amount of waste deposited, but also supported the local power industry by generating electricity and heat. The emission standards for installations producing energy from waste, as in the case of conventional power plants and combined heat and power plants, are very strict, therefore, the continuous monitoring of emitted pollutants is carried out, and waste gas treatment systems are developed based on the best available techniques (BAT). The article presents emission standards applicable to waste incineration plants, including duties in the field of the environment, as well as issues related to the installation as a source of energy. In addition, the currently functioning waste incineration plants in Poland have been briefly characterized, and development plans in this area in the country have been described.
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Abstract

This paper presents the main dilemma of development of the Polish energy sector on the 20th anniversary of the first liberalization directive of the European Union, which created the energy market. The situation in the Polish energy sector based on fossil fuels, its transformation into lower emission one is closely connected to the process of restructuring and further development of the mining sector. On the other hand, we are witnessing the development of RES, household installations producing electricity with storage and the electrification of public transport. The investments in new, large scale fossil fuel fired power plants are very expensive and not economically proven when electricity prices are low. Until the new direction of investment in energy sector will be decided, the option of the lasting of the operating existing power units seems to be a good proposal. Is the thesis: “The energy security of Poland should be fully based on indigenous sources, generation and distribution assets, delivering electricity to end users. Ensuring competitive energy prices to the economy and households, the market should be fully open to producers and consumers, including chip electricity arising from the European single market” the right assumption for the Polish energy policy?
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Abstract

The main purpose of the presented research is to investigate the partial discharge (PD) phenomenon variability under long-term AC voltage with particular consideration of the selected physical quantities changes while measured and registered by the acoustic emission method (AE). During the research a PD model source generating surface discharges is immersed in the brand new insulation mineral oil. Acoustic signals generated by the continuously occurred PDs within 168 hours are registered. Several qualitative and quantitative indicators are assigned to describe the PD variability in time. Furthermore, some longterm characteristics of the applied PD model source in mineral oil, are also presented according to acoustic signals emitted by the PD. Finally, various statistical tools are applied for the results analysis and presentation. Despite there are numerous contemporary research papers dealing with long-term PD analysis, such complementary and multiparametric approach has not been presented so far, regarding the presented research. According to the presented research from among all assigned indicators there are discriminated descriptors that could depend on PD long-term duration. On the grounds of the regression models analysis there are discovered trends that potentially allow to apply the results for modeling of the PD variability in time using the acoustic emission method. Subsequently such an approach may potentially support the development and extend the abilities of the diagnostic tools and maintenance policy in electrical power industry.
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Abstract

According to the European Environment Agency (EEA 2018), air quality in Poland is one of the worst in Europe. There are several sources of air pollution, but the condition of the air in Poland is primarily the result of the so-called low-stack emissions from the household sector. The main reason for the emission of pollutants is the combustion of low-quality fuels (mainly low-quality coal) and waste, and the use of obsolete heating boilers with low efficiency and without appropriate filters. The aim of the study was to evaluate the impact of measures aimed at reducing low-stack emissions from the household sector (boiler replacement, change of fuel type, and thermal insulation of buildings), resulting from environmental regulations, on the improvement of energy efficiency and the emission of pollutants from the household sector in Poland. Stochastic energy and mass balance models for a hypothetical household, which were used to assess the impact of remedial actions on the energy efficiency and emission of pollutants, have been developed. The annual energy consumption and emissions of pollutants were estimated for hypothetical households before and after the implementation of a given remedial action. The calculations, using the Monte Carlo simulation, were carried out for several thousand hypothetical households, for which the values of the technical parameters (type of residential building, residential building area, unitary energy demand for heating, type of heat source) were randomly drawn from probability distributions developed on the basis of the analysis of the domestic structure of households. The model takes the coefficients of correlation between the explanatory variables in the model into account. The obtained results were multiplied so that the number of hypothetical households was equal to 14.1 million, i.e. the real number of households in Poland. The obtained results allowed for identifying the potential for reducing the emission of pollutants such as carbon dioxide, carbon monoxide, dust, and nitrogen oxides, and improving the energy efficiency as a result of the proposed and implemented measures, aimed at reducing low-stack emission, resulting from the policy. The potential for emissions of gaseous pollutants is 94% for CO, 49% for NOx, 90% for dust, and 87% for SO2. The potential for improving the energy efficiency in households is around 42%.
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Abstract

This article presents data on the anthropogenic air emissions of selected substances (CO2, SO2, total suspended particles (TSP), dioxins and furans (PCDD/F), Pb and Cd) subject to reporting under the Climate Convention (UNFCCC) or the Convention on Long-range Transboundary Air Pollution (UNECE CLRTAP). It also presents the national emissions of these substances in 2014 by the major source categories and defines the share of metal production in these emissions. Analysis is based on national emission inventory reports. Most important source of air emission in case of CO2 and SO2 is 1.A.1 Energy industries category. TSP and PCDD/F are emitted mainly from fuel combustion in small sources (i.a. households). Emission of heavy metals (Pb and Cd) is connected mostly with 1.A.2. Manufacturing industries and construction category. Metallurgy is significant source of emission only for lead and cadmium from among all considered substances. The shares of particular sectors in the national emissions of given pollutants are important, in view of the possible reduction measures and the determination in which industries they could bring about tangible results.
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Abstract

Natural gas combustion was carried out in air enriched with oxygen in the amount of 25 and 29% with addition of CO2 in place of part of nitrogen. The research was carried out at different flow rates of gas and oxygen excess ratios. The concentration of CO and NOx was analyzed. It has not been proved that the increased oxygen concentration influences significantly the CO concentration. However, the addition of CO2 caused a substantial variability of CO concentration in the exhaust gas, in contrast to the concentration of NOx which decreased monotonically. Model calculations, performed with use of FactSage, indicate an increase in the concentration of CO not only for the air enriched with oxygen, but after adding CO2 too, as well
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Abstract

The primary methods of reducing nitrogen oxides, despite the development of more advanced technologies, will continue to be the basis for NOx reduction. This paper presents the results of multivariate numerical studies on the impact of air staging on the flue gas temperature and composition, as well as on NOx emissions in a OP 230 boiler furnace. A numerical model of the furnace and the platen superheater was validated based on measurements using a 0-dimensional model of the boiler. Numerical simulations were performed using the ANSYS Workbench package. It is shown that changes in the distribution of air to OFA nozzles, the angle of the air outflow from the nozzles and the nozzle location involve a change in the flue gas temperature and in the volume of NOx and CO emissions at the furnace outlet.
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Abstract

CO, NO, NO2 and dust concentrations from combustion of deciduous wood (birch, beech, lime-tree) logs and pellets in two heating boilers (15 and 25 KW), situated in a heat station were investigated. Time dependences of pollutant concentrations as well as the impact of temperature in the combustion chamber and oxygen concentration on pollutant concentrations were presented. Pollutant emission indices have been estimated.
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Abstract

The paper deals with the preparation and measurement of an experimental polymer graphite cathode that seems to be a promising and cheap source of electrons utilizing cold field-emission in high- and ultra-high vacuum. Polymer graphite seems to be a proper material as it contains a large amount of hybridized carbon with a low degree of surface oxidation and silicon monoxide (SiO). Within the frame of this work, a special experimental method of tip preparation has been designed and tuned. This method is based on ion milling inside a dual-beam electron microscope enabling to obtain ultra-sharp tips of a diameter smaller than 100 nm with a predefined opening angle. The charge transport within experimental samples is evaluated based on results provided by the noise spectroscopy of the total emission current in the time and frequency domains.
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Abstract

Results of the study examining carbon monoxide and nitric oxide concentrations while burning different types of agricultural biomass: coffee husk pellets alone or in combination with wheat straw pellets and cherry stones, sewage sludge pellets, corn stover briquettes and a mixture of rye straw briquettes and miscanthus briquettes were presented. The combustion was performed in a 50 kW boiler type Biowarmer with a cast-iron moving step grate. The temperature in the combustion chamber did not exceed 800 ◦C. For all biomass types, only brittle slag was generated in the furnace, which was easily broken by a reciprocating movement of the grate. Carbon monoxide concentration in the flue gas except for the case of sewage sludge pellet firing did not exceed the permitted value of 3000 mg/m3 and nitric oxide concentration 515 mg/m3, both presented for 10% O2 concentration in the flue gas based in dry gas. Hydrocarbon concentrations for all test runs were close to zero.
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Abstract

This study investigates cadmium (Cd) accumulation in the plant leaves of juglans regia (walnut) and cydonia oblanga (quince) trees related to traffic emissions on the highway roadside. The plant leaf samples were collected from 20 sites on the D-100 Highway roadside and washed with deionized water before analyzed. Determination of Cd was carried out using an inductively-coupled plasma-mass spectrometer after microwave digestion of the samples. Cd concentration on the plant leaves was found to be between 0.04–0.11 mg/kg. In order to determine the traffic-based emissions, vehicles were counted and an emission inventory was prepared. 0.18 tons of Cd was found to be delivered into the atmosphere every day. Cd accumulation depends on traffic density because there were no residential area and industrial plants. The distribution of Cd accumulation caused by traffic emissions was mapped by using a geographic information system (GIS). The maps showed that the Cd accumulation was high in the areas near the highway and then gradually decreased by moving away from the highway.
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Abstract

Non-invasive damage monitoring of concrete structures by means of Acoustic Emission (AE) requires multitransducers, multi-channel acquisition, high sampling frequency and long observation time. Owing to its propagation in concrete, the signal from AE reduces its amplitude during the propagation, and, consequently, some events can be lost due to lower signal intensity than the trigger level set on one sensor only. The innovative proposal discussed in the paper consists in the introduction of a Flat Amplifier and Trigger generator block (FAT) in order to generate a logical trigger when the AE is detected by any transducer. Experimental tests confirm the effectiveness of the FAT to acquire all the AE events and to increase the evaluation accuracy of damage indexes.
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Abstract

Tests for combustion of hay and sunflower husk pellets mixed with wood pellets were performed in a horizontal-feed as well as under-feed (retort) wood pellet furnace installed in boilers with a nominal heat output of 15 and 20 kW, located in a heat station. During the combustion a slagging phenomenon was observed in the furnaces. In order to lower the temperature in the furnace, fuel feeding rate was reduced with unaltered air stream rate. The higher the proportion of wood pellets in the mixture the lower carbon monoxide concentration. The following results of carbon monoxide concentration (in mg/m3 presented for 10% O2 content in flue gas) for different furnaces and fuel mixtures (proportion in wt%) were obtained: horizontal-feed furnace supplied with hay/wood: 0/100 - 326; 30/70 - 157; 50/50 - 301; 100/0 - 3300; horizontal-feed furnace supplied with sunflower husk/wood: 50/50 - 1062; 67/33 - 1721; 100/0 - 3775; under-feed (retort) furnace supplied with hay/wood: 0/100 - 90; 15/85 - 157; 30/70 - 135; 50/50 - 5179; under-feed furnace supplied with sunflower husk/wood: 67/33 - 2498; 100/0 - 3128. Boiler heat output and heat efficiency was low: 7 to 13 kW and about 55%, respectively, for the boiler with horizontal-feed furnace and 9 to 14 kW and 64%, respectively, for the boiler with under-feed furnace.
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Abstract

The impact of the fuel feeding mode (continuous or periodic with different stand-by/operation time ratios) on carbon monoxide (CO) and nitrogen oxides (NO, NOx) concentration values in the flue gas was analysed for coniferous wood pellet firing. Experiments were performed in a 25 kW water boiler equipped with an over-fed wood pellet furnace located in a full scale heat station simulating real-life conditions. Influence of oxygen concentration and temperature in the combustion chamber on carbon monoxide and nitrogen oxide concentrations was presented in diagrams. Dust and hydrocarbon concentrations were also monitored. It was concluded that the commonly used periodic fuel supply does not necessarily cause a significant increase of carbon monoxide concentration, as compared to the continuous fuel feeding mode. Continuous fuel supply can even induce higher carbon monoxide concentrations when fuel mass stream is not chosen properly. Each time new fuel type is used in a specific furnace, one should perform experiments to determine the adequate settings (stand-by/operation time ratio, fuel mass streams, air stream) to obtain the optimal, lowest possible emission for a certain boiler heat output
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Abstract

An acoustic emission method (AE) is widespread and often applied for partial discharge (PD) diagnostics, mainly due to its ease of application as well as noninvasiveness and relatively high sensitivity. This paper presents comparative analysis of AE signals measurement results archived under laboratory conditions as well as on-site actual AE signals generated by inside PDs in electrical power transformer during its normal service. Three different PD model sources are applied for laboratory research: point to point, multipoint to plate and surface type. A typical measuring set up commonly used for on-site transformer PD diagnostics is provided for the laboratory tasks: piezoelectric joint transducer, preamplifier, amplifier and measuring PC interface. During the on-site research there are three measuring tracks applied simultaneously. Time domain, time-frequency domain and statistical tools are used for registered AE signals analysis. A number of descriptors are proposed as a result of the analysis. In the paper, at- tempt of AE signals descriptors, archived under laboratory condition application possibilities for on-site PD diagnostics of power transformers during normal service is made.
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Abstract

Electric cars (SE) are currently considered to be one of the best ways to reduce CO2 and other air emissions in the transport sector as well as noise in cities. They can reduce the dependency of road transport on imported oil in a visible way. Nevertheless, the demand for electricity for a large amount of SE in road transport is not insignificant and has an impact on the power system. The article analyzes the potential impact of SE on the demand, supply, structure and costs of electricity generation as well as emissions as a result of introducing 1 million SEs by 2025 on Polish roads, and tripling this number by 2035. The competitive electricity market model ORCED was used for the calculations. The results of the analysis indicate that regardless of the charging strategy, the demand for SEs causes a slight increase in the overall electricity demand in Poland and consequently also a slight increase in power generating costs. Even a large increase in SEs in road transport will result in a rather moderate demand for additional generation capacity, assuming that power companies will have some control over the mode of charging cars. The introduction of SEs will not reduce CO2 emissions compared to conventional cars in 2025, on the contrary will increase them regardless of the loading strategy. In 2035 however, the result depends on the charging scenario and both the increase or decrease of emissions is possible. Electric vehicles will increase SO2 net emissions, but they will contribute to a decrease in the net emissions of particulates and NOx.
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Abstract

One of the most important issues that power companies face when trying to reduce time and cost maintenance is condition monitoring. In electricity market worldwide, a significant amount of electrical energy is produced by synchronous machines. One type of these machines is brushless synchronous generators in which the rectifier bridge is mounted on rotating shafts. Since bridge terminals are not accessible in this type of generators, it is difficult to detect the possible faults on the rectifier bridge. Therefore, in this paper, a method is proposed to facilitate the rectifier fault detection. The proposed method is then evaluated by applying two conventional kinds of faults on rectifier bridges including one diode open-circuit and two diode open-circuit (one phase open-circuit of the armature winding in the auxiliary generator in experimental set). To extract suitable features for fault detection, the wavelet transform has been used on recorded audio signals. For classifying faulty and healthy states, K-Nearest Neighbours (KNN) supervised classification method was used. The results show a good accuracy of the proposed method.
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Abstract

In this paper the influence of high power airborne ultrasound on drying biological material (Lobo apple) properties is considered. Apple samples were dried convectively at 75 ◦C and air flow of 2 m/s with and without ultrasound assist at 200W. During experiments, sun-drenched and not sun-drenched part of fruits were considered separately to show, how the maturity of the product influences dry material properties. Dried apple crisps in a size of small bars were subjected to compression tests during which acoustic emission (AE) was used. Analysis of AE and strength test results shows that correlations between received acoustic signals and sensory attributes (crispness, brittleness) of dried apples can be found. It was noted that ultrasound improved fruit brittleness in comparison with pure convective processes, where fruit maturity determines a kind of destruction and behaviour of dried apple crisps.
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Abstract

The article presents research results of physico-chemical and environmental issues for the dust generated during dedusting of the installation for the processing and preparation of moulding sand with bentonite. Particular attention was paid to the content of heavy metals and emission of gases from the BTEX group, which is one of the determinants of the moulding sands harmfulness for the environment. The analysis of heavy metals in the test samples indicate that there is an increase of the content of all metals in the dust compared to the initial mixture of bentonite. The most significant (almost double) increase observed for zinc is probably related to the adsorption of this element on the dust surface by contact with the liquid metal. The study showed, that dust contained more than 20% of the amount of montmorillonite and had a loss on ignition at a similar level. The addition of 1% of dust to the used moulding sand results in almost 30% increase in the total volume of gases generated in casting processes and nearly 30% increase of the benzene emission.
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Abstract

No-bake process refers to the use of chemical binders to bond the moulding sand. Sand is moved to the mould fill station in preparation for filling of the mould. A mixer is used to blend the sand with the chemical binder and activator. As the sand exits the mixer, the binder begins the chemical process of hardening. This paper presents the results of decomposition of the moulding sands with modified ureafurfuryl resin (with the low content of furfuryl alcohol below 25 % and different activators: organic and inorganic) on a quartz matrix, under semi-industrial conditions. Investigations of the gases emission in the test foundry plant were executed according to the method extended in the Faculty of Foundry Engineering (AGH University of Science and Technology). Article presents the results of the emitted chosen aromatic hydrocarbons and loss on ignition compared with the different activators used to harden this resin. On the bases of the data, it is possible to determine the content of the emitted dangerous substances from the moulding sand according to the content of loss on ignition.
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Abstract

The article presents the results concerning the use of clustering methods to identify signals of acoustic emission (AE) generated by partial discharge (PD) in oil-paper insulation. The conducted testing featured qualitative analysis of the following clustering methods: single linkage, complete linkage, average linkage, centroid linkage and Ward linkage. The purpose of the analysis was to search the tested series of AE signal measurements, deriving from three various PD forms, for elements of grouping (clusters), which are most similar to one another and maximally different than in other groups in terms of a specific feature or adopted criteria. Then, the conducted clustering was used as a basis for attempting to assess the effectiveness of identification of particular PD forms that modelled exemplary defects of the power transformer’s oil-paper insulation system. The relevant analyses and simulations were conducted using the Matlab estimation environment and the clustering procedures available in it. The conducted tests featured analyses of the results of the series of measurements of acoustic emissions generated by the basic PD forms, which were obtained in laboratory conditions using spark gap systems that modelled the defects of the power transformer’s oil-paper insulation.
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Abstract

The paper investigates the air quality in the urban area of Warsaw, Poland. Calculations are carried out using the emissions and meteorological data from the year 2012. The modeling tool is the regional CALMET/CALPUFF system, which is used to link the emission sources with the distributions of the annual mean concentrations. Several types of polluting species that characterize the urban atmospheric environment, like PM10, PM2.5, NOx, SO2, Pb, B(a)P, are included in the analysis. The goal of the analysis is to identify the most polluted districts and polluting compounds there, to check where the concentration limits of particular pollutants are exceeded. Then, emission sources (or emission categories) which are mainly responsible for violation of air quality standards and increase the adverse health effects, are identified. The modeling results show how the major emission sources – the energy sector, industry, traffic and the municipal sector – relate to the concentrations calculated in receptor points, including the contribution of the transboundary inflow. The results allow to identify districts where the concentration limits are exceeded and action plans are needed. A quantitative source apportionment shows the emission sources which are mainly responsible for the violation of air quality standards. It is shown that the road transport and the municipal sector are the emission classes which substantially affect air quality in Warsaw. Also transboundary inflow contributes highly to concentrations of some pollutants. The results presented can be of use in analyzing emission reduction policies for the city, as a part of an integrated modeling system.
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