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 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.
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.
The Ukrainian energy sector’s crucial problems, in particular, the outmoded equipment, the power
infrastructure shortcoming and a significant backlog in the energy supply quality from the European
one, based on the SAIDI (System Average Interruption Duration Index) indicator comparison,
has been disclosed in this article. A considerable break in the energy supply quality in both
rural and urban settlements has been also revealed. The current state of the alternative energy development
has been described, the energy generation structure, as well as the rates of development
of the renewable energy sources’ usage have been analyzed. Some challenges in the imbalance of
the renewable energy sources’ usage and their analyzed consequences have been identified, among
others, the generation volume abruptness by both SPP and WPP, requiring maneuvering with the
traditional sources’ employer. The negative effect of the “green” tariff as the main priming stimulus
for the renewable energy facilities’ construction has been proven. Generally and particularly, the
financial influence level on the state has been analyzed, being manifested in the debts’ accumulation
to energy producers. The residual capability of solving the problems of alternative energy
development has been considered, in particular, the “green” auctions announced by the state, the
formation of the optimal predicted level of energy generation by SPP and WPP in order to prevent
sharp disparities in both electricity demand and supply. The biogas plants’ facilities as a ponderable
choice to both solar and wind generation have been analyzed.
Subnetwork with two nodes shared with entire ventilation network can be separated as its part. For the network under common ventilation conditions, one of these nodes will become the subnetwork starting node, while the other will be the subnetwork end node. According to the graphs theory, such a piece of the network can be considered as a subgraph of the graph representing the entire ventilation network. A special feature of that subgraph is lack of predecessors of the subnetwork starting node and lack of successors of the subnetwork end node. Ventilation district of a mine may be often treated as a subnetwork. Vicinity is a part of the network which is not separated as subnetwork. In the case of a ventilation district its vicinity forces air flow through the district. The alternative characteristic curve of the vicinity can therefore be compared to the characteristics curve of a fictional fan that forces the airflow in the district.
The alternative characteristics (later in the text: the characteristics) of the vicinity of the ventilation district in an underground mine strongly influence air quantity and therefore play a crucial role in the reduction of methane, fire and thermal hazards. The role of these characteristics and proper selection of their approximating function were presented in the article.
The reduction of resistance of an intake stopping (having influence on entire resistance of a ventilation district) produces increased airflow in the district. This changes of airflow in the district caused by a variation in internal resistance (e.g. by opening an internal regulation stopping) depends on the characteristic of the vicinity of the district. Proper selection of its approximating function is also important for this matter.
The methods of determination of the alternative characteristic curve of the district vicinity are presented. From these procedures it was possible to obtain the results of air quantities and differences in isentropic potentials between an inlet and an outlet to/from the ventilation district. Following this, the characteristics were determined by graphic and analytic methods. It was proved that, in contrast to flat vicinity characteristics, steep ones have a smaller influence on the airflow modification in the district (which are caused by a regulation of the district resistance). The characteristic curve of the vicinity determines the ability to regulate air quantity and velocity in the district.
Although the usefulness of alternative assessment in second language (L2) classrooms has been extensively recognized by scholars, the use of the various types of alternative assessment in English as a Foreign Language (EFL) contexts has not received adequate attention by L2 practitioners. To contribute to this line of research, the present research sought to examine the impact of a portfolio-based writing instruction on writing performance and writing anxiety of EFL students. To this end, a number of 41 EFL learners were recruited as the participants of this study. They were then randomly divided to an experimental group (N=21) and a control group (N=20). The participants in the experimental group received portfolio-based writing instruction, whereas the control group received the regular writing instruction with no archiving of students’ drafts in portfolios. Timed-writing tasks and the Second Language Writing Anxiety Inventory (SLWAI) were employed to collect the data. The results obtained from ANCOVA analysis revealed that the portfolio-based writing instruction aided the participants in improving their writing performance more than the control group. Moreover, it was found that the use of portfolios significantly reduced the L2 writing anxiety of the participants while the traditional writing instruction did not have any significant impact on L2 writing anxiety of the control group. The pedagogical implications for portfolio-based writing instruction are discussed finally.
This paper presents an innovative solution for increasing life of lead-acid batteries used in a glider launcher. The study is focused on upgrading a charging system instead of a costly full replacement of it. Based on literature review, the advanced three-stage charging profile was indicated. The new topology of the power converter was proposed and a simulation model was developed. A simulation study was performed which leads to a conclusion that the suggested solution can be successfully applied to the studied device. As a result, the conclusion of this work is the recommendation for modification of the launching system with an additional converter enabling 3 stage charging.
In the article the Author presents the typology of alternative history and in its light he characterises the historical writings of Jerzy Łojek, in particular his approach towards history of November Uprising, 1830–1831.
The article attempts to show Szczepan Twardoch’s novel Drach as a literary version of the counter- history, which constitute an alternative vision of the past. The theory of counter-history was taken from Michel Foucault’s writings Society Must Be Defended. By this conception Foucault tried to restore the history of those excluded from the offi cial historical discourse.
en
pl
