This paper presents a study on nitrogen conversion in oxy-fuel coal combustion in a pilot scale CFB 0.1 MWth facility. The paper is focused on fuel-N behaviour in the combustion chamber when the combustion process is accomplished under oxy-fuel CFB conditions. The analysis is based on infurnace sampling of flue gas and calculations of the conversion ratios of fuel-nitrogen (fuel-N) to NO, NO2, N2O, NH3 and HCN. For the tests, O2/CO2 mixtures with the oxygen content of 21 vol.% (primary gas) and with the oxygen content varied from 21 to 35 vol.% (secondary gas), were used as the fluidising gas. Measurements were carried out in 4 control points located along the combustion chamber: 0.43 m, 1.45 m, 2.50 m and 4.88 m. Results presented below indicate that an increased oxygen concentration in the higher part of the combustion chamber has strong influence on the behaviour of fuel based nitrogen compounds.
The article discusses issues related to the generation, use, and transboundary movement of waste labeled with the code 191210 according to the waste catalogue regardless of its origin (municipal, industrial or mixed). Data contained in voivodship reports related to waste management and information about transboundary shipments shared by the Chief Inspectorate of Environmental Protection were also used in the article. The imbalance in the amount of produced and energetically used alternative fuels in Poland in the years 2015 to 2017 has been confirmed. This affects the economy of the waste management sector involved in the production of alternative fuels. The oversupply causes the prices of alternative fuels to fall and increases the need for subsidies in the case of the recovery or disposal of alternative fuels of lower quality. In the near future one should expect a stabilization of the supply of combustible waste to the cement industry, which is now beginning to achieve its technological potential; this is due to a high degree of replacement of fossil fuels. One should also expect an increase in the demand for alternative fuels from the commercial power sector and heating sector. It has been shown that much more alternative fuel is imported than exported from Poland. The amount of imported alternative fuel in the market is relatively low compared to the amount of fuel produced in the country. This oversupply affects, although not significantly, the possibility of using domestic waste for energy recovery. The export of the alternative fuel produced in the country is a favorable phenomenon when there is no possibility of sale on the domestic market. It seems rational, especially in the case of exports from installations producing fuels in border provinces.
Protection of the environment and counteracting global warming require finding alternative sources of energy. One of the methods of generating energy from environmentally friendly sources is increasing the share of gaseous fuels in the total energy balance. The use of these fuels in compression-ignition (CI) engines is difficult due to their relatively high autoignition temperature. One solution for using these fuels in CI engines is operating in a dualfuel mode, where the air and gas mixture is ignited with a liquid fuel dose. In this method, a series of relatively complex chemical processes occur in the engine's combustion chamber, related to the combustion of individual fuel fractions that interact with one another. Analysis of combustion of specific fuels in this type of fuel injection to the engine is difficult due to the fact that combustion of both fuel fractions takes place simultaneously. Simulation experiments can be used to analyse the impact of diesel fuel combustion on gaseous fuel combustion. In this paper, we discuss the results of simulation tests of combustion, based on the proprietary multiphase model of a dual-fuel engine. The results obtained from the simulation allow for analysis of the combustion process of individual fuels separately, which expands the knowledge obtained from experimental tests on the engine.
The application of renewable energy sources poses the problems connected with output volatility. In order to decrease this effect the energy storage technologies can be applied, particularly fuel cells connected with hydrogen storage. In this paper the application of SOFC system for a household in Poland is proposed. Economic and technical analysis is performed. It was found that the proposed installation is profitable after 25 years of operation when compared with conventional solution - heat pumps and gas-fired boilers.
In this paper some issues of the transition process from air- to oxy-combustion were investigated. Advantages of flexible combustion were described. Flexible combustion tests carried out at four European plants and five plants outside Europe of different scales of process and test parameters were presented. An analysis of the transition time from air to oxy-combustion of different laboratory and pilot scale processes was carried out. The “first-order + dead time” approach was used as a model to describe transition process. Transitional periods between combustion modes and characteristic parameters of the process were determined. The transition time depends not only on the facility’s capacity but also it is impacted by specific operational parameters.
The problem of the optimal driving technique during the fuel economy competition is reconsidered. The vehicle is regarded as a particle moving on a trace with a variable slope angle. The fuel consumption is minimized as the vehicle covers the given distance in a given time. It is assumed that the run consists of two recurrent phases: acceleration with a full available engine power and coasting down with the engine turned off. The most fuel-efficient technique for shifting gears during acceleration is found. The decision variables are: the vehicle velocities at which the gears should be shifted, on the one hand, and the vehicle velocities when the engine should be turned on and off, on the other hand. For the data of students’ vehicle representing the Faculty of Power and Aeronautical Engineering it has been found that such driving strategy is more effective in comparison with a constant speed strategy with the engine partly throttled, as well as a strategy resulting from optimal control theory when the engine is still active.
The development of air transport affects elements of the aviation fuel market. In recent years an increase in both the number of passengers and the number of passenger operations has been observed. This phenomenon also concerns passengers and the number of operations served by Polish airports which translates into more and more fuel consumption in Poland. The authors of the study tried to approximate the characteristics of aviation fuels used in various types of aircrafts. The most important of them, from the perspective of the Polish aviation sector, include Jet. This type of fuel plays a key role in civil aviation. In the article, the enterprises operating in the analyzed sector were also reviewed. The empirical part of the article is devoted, in turn, to the analysis of changes in air passenger transport in Poland and changes in Jet fuel prices on the Polish fuel markets. The conducted research shows that the dynamics of changes in the number of passengers, as well as the number of passenger operations at Polish airports were characterized by an upward trend, and the increase in the number of passengers was driven not only by a larger number of available flights, but also by such factors as: increasing the capacity of aircraft and increasing the fill rate for seats. The authors have also attempted to examine the strength of dependence between the number of passengers deciding to use Polish airports and Jet fuel prices, which in recent years have undergone significant fluctuations. For this purpose, the value of Pearson’s linear correlation coefficient was used and the analyzed period covered the years 2011–2017. The data on passenger traffic used in the study came mainly from periodic reports prepared by the Civil Aviation Office (ULC).
Low emission has a significant impact on air quality in Poland. Low sources are found which lead to high concentrations of pollutants in the area inhabited by humans. The effects of low emissions on health and life in the polluted areas (Małopolska, Silesia) are conducive to radical decisions regarding the quality of solid fuels and their combustion facilities. At present, local anti-smuggling laws have been introduced in the two provinces banning the burning of the most emitting fuels such as mules, flotoconcentrates and lignite. Regional EU-funded programs for the use of renewable energy sources (RES) and energy efficiency improvement will transition to the implementation phase of the approved projects as of 2017. This is expected to significantly reduce energy consumption for heating buildings and replacing old boilers and automatic furnaces with low-emission heating devices. In the case of households, proving that the residential building has adequate energy efficiency characteristics is necessary in order to receive co-financing for replacing an old solid fuel boiler with a new low-emission boiler,. The paper will present the current situation on the regulation of the fuel market in the household and small–scale consumer sector and the proposal for changes to the law on monitoring and control of solid fuel quality. Another important issue will be significant changes in heating up to 500 kW, proposed by the Ministry of Development in October 2016. The proposed regulation precedes the implementation of the Ecodesign Directive, which will come into effect as of 2022 for room heaters and heating furnaces up to 500 kW for solid fuels. All these actions will help reduce low emissions and improve energy efficiency.
The most common chemical’s spills in typical transportation accidents are those with petroleum products such as diesel fuel, the consequence of which is an extensive pollution of the soil. In order to plan properly fuel recovery from the soil, it is important to gain information about the soil depth which may be affected by pollutant and to predict the pollutant concentration in different soil layers. This study deals with the impact of basic atmospheric conditions, i.e. air temperature and humidity on the diesel fuel migration through the soil. The diesel fuel was spilled into columns (L = 30 cm; D = 4.6 cm) filled with sandy and clay soil samples, and its concentrations at various depths were measured after 11 days under various air temperature (20 and 40°C) and relative humidity (30–100%) conditions. The effects observed were explained by understanding physical processes, such as fuel evaporation, diffusion and adsorption on soil grains. The increase in temperature results in higher fuel evaporation loss and its faster vertical migration. The relative humidity effect is less pronounced but more complex, and it depends much on the soil type.
The paper describes a fuel cell based system and its performance. The system is based on two fuel cell units, DC/DC converter, DC/AC inverter, microprocessor control unit, load unit, bottled hydrogen supply system and a set of measurement instruments. In the study presented in the paper a dynamic response of the proton exchange membrane (PEM) fuel cell system to unit step change load as well as to periodical load changing cycles in the form of semi-sinusoidal and trapezoidal signals was investigated. The load was provided with the aid of an in-house-developed electronic load unit, which was fully PC controlled. The apparatus was commissioned by testing the steady-state operation of the module. The obtained efficiency of the fuel cell shows that the test apparatus used in the study provides data in substantial agreement with the manufacturer’s data.
The paper presents a concept of producing energy on the basis of modern alternative fuels to be burnt in low- and medium-power stokerfired boilers. The thermal energy contained in water vapour and hot water will be utilized in producing, in combination, of electrical energy, and for heating of cubature objects. Modern alternative fuels in the form of briquettes and pellets will be produced from hard coals and municipal waste other than hazardous. There have been presented the properties of alternative fuels obtained, and the concept of their utilization in the process of energy production in cogeneration.
This paper is devoted towards life cycle economic analysis (LCEA) of a solar photovoltaic (PV) powered tri-cycle. The paper is meant to propose a more systematic approach in determining the optimum use of scarce resources in order to determine the most cost-effective option of the solar tri-cycle. This analysis is based on the life cycle cost of this solar vehicle, involving its comparison with the customary fuel-based tri-cycle which exhibits the relatively less expenditure of the solar alternative. The economic analysis takes into account the fact that over 20 years, the overall price of solar component, replacement and electricity charges, is much lower as compared to that of a fuel-based tri-cycle in India taking into consideration the fuel cost, maintenance and annual inflation over the same period.
Currently is the biggest problem of metallurgical companies the increase of fossil fuel prices and strict environmental regulations. As a result of this, companies must look for alternatives that would reduce the amount of fossil fuels and reduce emissions. Wood sawdust has huge energy potential, which can be used in the process of agglomerate production. This type of energy is locally available, has some similar properties as fossil fuels and is economically advantageous. For these reasons, experimental study using laboratory agglomeration pan was realized to study the possibility of agglomerate production with a mixed fuel. Experimental results show the viability of mixed fuel use in the agglomeration process, but also show significant possibility for improvement. The maximum acceptable substitution ratio, which corresponds to qualitatively suitable agglomerate is 20% of pine sawdust. Based on the realized experiments and the obtained results we have acceded to the intensification of the agglomeration process with an objective to increase the amount of added substitution fuel while maintaining the required quality of agglomerate.
The dynamics of economic development determines the need to develop technologies for waste recycling especially the acquisition of condensed fuels for the needs of the local diversification of energy sources. In a short time, Poland will probably lack its own produced electricity. To apply the process of diversification of energy sources, by developing methods of generating energy from waste, it becomes crucial to protect the environment. The use of cogeneration technology based on fuels derived from waste, in particular concentrated oil and gas fuels, is becoming more common and provides the basis for securing the energy supply in the preferred diversification process. Plastic waste processing in the controlled depolymerization process, which is the reverse of the polymerization process for hydrocarbon recovery – uses petroleum derivatives its production. At present, the greatest interest arises in the material recovery of plastics and rubber in the process of anaerobic thermal decomposition (thermolysis/pyrolysis), which is used on an industrial scale and consists in the degradation of polymer bonds into low molecular weight. The imperative of a modern economy is to obtain energy from fuels from waste treatment, including hazardous waste, preferably in the cogeneration process. The fuel obtained from waste may be used to obtain thermal or electric energy in order to diversify energy sources. The article presents innovative Polish technologies of obtaining fuel in processes of anaerobic thermal decomposition mainly of elastomeric and polymeric waste (including hazardous ones) for direct application in power generators of various power.
The expected demand for hard coal intended for the households will progressively be decreasing. This is directly related to the introduced anti-smog resolutions, as well as the growing level of environmental awareness. However, it should be noted, that the use of the modern home heating boilers will result in an increase in the demand for medium coal sizes. The shortfall of this type of coal is already observed on the market. Therefore, its import is necessary. One of the solutions to increase the supply of the medium coal sizes is the production of coal briquettes. Moreover, their use will consequently lead to reduced emissions.
The paper presents a comparison of emissions from the combustion of coal briquettes and hard coal in home heating boilers. The briquettes were characterized by significantly lower emissions than hard coal (by 52% on average). The particulate matter emissions were lower by 70%. This may significantly contribute to improving air quality in Poland and in addition, limit the occurrence of smog. The possibility of further emission reduction by using low-emission fuels as briquette components was presented. The average relative emission reduction compared to hard coal for the analyzed fuels was estimated as follows: 62% for coal char, 57% for coke, 51% for charcoal/biocarbon, 49% for anthracite, 45% for torrefied biomass, and 33% for peat.
Furthermore, the issue of the mercury content in the analyzed fuels was discussed. The lowest mercury content was found in biomass fuels, in particular biomass after thermal treatment (torrefied biomass, biocarbon, and charcoal). Fuels produced from hard coal in the pyrolysis process (coal char and coke) were characterized by very low mercury content as well.
At present, electromobility is a very dynamically developing segment and at the same time has many unknowns that enterprises that want to develop this area in their structures have to face. This article aims is to show the difficulties of electromobility development from the perspective of Polish energy groups which are closely related to this area, especially considering the obligations imposed on energy companies by the legislator. The electrification of transport has become a reality and in order to use its potential to develop new services or implement innovations and new technologies, it is necessary to identify development barriers and prepare a response plan. The authors of the article decided to show the formal and legal implications for the development of electromobility in Poland in first order, and then examine the development strategies of Polish energy groups in terms of electromobility and indicate explored areas related to it. The next section focuses on identifying the main barriers to the implementation of business models, classifying them according to the following factors: economic, operational, technical, social and legal. This presentation of the problem allows for an in-depth recognition of the issue and realizing that in order to achieve the goals set by the Legislator, close cooperation of all stakeholders is necessary both at the national and local level, while engaging energy groups, financial companies, electric vehicle manufacturers, and above all local government units in these activities.