A constant growth of the multimaterial waste production can be observed in the recent years. The multimaterial waste that contain aluminum are especially hard to process due to the fact that multiple layers of various materials are bonded permanently. Tetra-Pak waste contain high amounts of paper (approx. 70%) and are usually processed in papermills in order to recover cellulose. The overview on the methods used to process waste as well as the characteristics of the produced waste are presented in the paper. The application of pyrolysis has many advantages: the products are characterized by a high calorific value and can be used as fuels, and the process itself is much more environmentally friendly than the chemical methods used currently. The tests were performed with a special focus on the minimization of the aluminum oxidation level, so that in can be further processed. In order to determine the decomposition temperature of the individual components of the examined materials, the tests started with a thermogravimetric analysis of the pyrolysis process performed with the application of argon. The next step were the pyrolysis tests on a laboratory scale installation aimed in the verification of the results obtained during the thermogravimetry.
The article presents physiochemical parameter changes in water supply network of Zielona Góra. On the basis of the obtained test results, the impact of prolonged retention of water in the network on its quality was determined, at the measuring points located on the territory of Zielona Góra.
It was shown that together with an increase in distance of measuring points from Water Treatment Plant, content of mainly iron, turbidity and colour increased too. In the results analysis, it was determined that retention time and water distribution are the most significant factors in the network contributing to deterioration of water quality at measuring points.
Andrzej Aniszewski, Rafał Ciepłuch and Norbert Laskowski
The paper contains a review of dimensionless experimental dependencies determining the coefficient of transverse dispersion Dy. In the course of the dimensional analysis, dimensionless experimental dependencies describing the dispersion of pollutants in groundwater with hydraulic and physical parameters of soil in the case of steady and uniform groundwater motion were presented. The analysis allowed the determination of dimensionless practical relationships defining the dispersion factor in the perpendicular direction to the main flow direction.
Łukasz Cieślikiewicz, Michał Wasik, Michał Kubiś, Piotr Łapka, Marcin Bugaj, Karol Pietrak, Tomasz S. Wiśniewski, Piotr Furmański and Mirosław Seredyński
The paper presents development of an experimental stand with centrally located specimen for the investigation of heating and drying processes in porous building materials. Additionally, the paper contains preliminary results of measurements which test and verify the assumed operation conditions of the stand. In order to control parameters of air which was used to heat and dry the specimen, the stand was operating in a closed loop and was equipped with several elements, i.e., the cooler (humidity condenser), fan with variable rotation speed, humidifier and heater. Moreover, the stand consisted of two square and parallel ducts with air streams which had identical parameters. This allowed for two measurements at the same time.
Evaluation of thermodynamic efficiency of a power plant is usually performed using the method of so-called thermal diagnostics, based on energy balancing. Energetic analysis is however suitable only for a quantitative assessment and for comparing similar technologies. In order to properly assess the origins of energy losses in the given system, an exergetic analysis has to be applied. The paper describes the rules of exergetic diagnostics, which greatly extends the potential of classic thermal diagnostics. A calculation example of a combined cycle power plant is included. The example demonstrates the potential of exergetic diagnostics for locating exergy losses and explains the reasons for increased consumption of fuels by comparing two working conditions of the system: reference and operational.
The following paper focuses on the electric vehicles sector development and its possible influence on power system load in Poland. The goal is to estimate the increase of power demand resulting from the electric cars charging. First of all, the current legal environment, which provides a framework for the e-mobility sector evolution, was described. Furthermore, the technical process of electric vehicles charging was depicted and the applicable methods of cooperation between e-mobility and power system were proposed. The quantitative analysis of the impact of the electric vehicles charging on the power demand in the National Power System was conducted. The input data and adopted assumption were specified. The structure of the calculation model and the differences between analyzed scenarios were described. The outcome obtained for the National Power System and Warsaw distribution area were presented.
Otto Mierka, Miroslav Variny, Ingrida Skalíková, Peter Sámel, Ján Kizek, Róbert Súth and Karol Nagy
A study on natural gas saving and emissions decrease in the public health care sector is presented. The analyzed hospital complex belongs to the largest ones in Slovakia and uses both hot water and water steam for heating purposes. Visual steam system inspection revealed serious inefficiencies, including steam venting, missing pipelines insulation and obsolete steam sources with dysfunctional blow-down system. Defined experiment with stepwise steam appliances shutdown enabled quantification of excess natural gas consumption due to these inefficiencies. Measures proposed for the solution of this state are inexpensive, with a short payback period. The expected natural gas savings amount up to 3200 MWh/year, which represents roughly 50% of the total natural gas consumption in the hospital complex.
Performance characteristics are an indicator of both, the technical as well as aesthetic state of buildings. Aesthetic needs are in disagreement with the merciless aging process. The beauty of a city is formed not only by the original forms of new residential buildings, but also by existing tenement housing; thus preserving their aesthetics becomes a necessity. One of the most important problems connected with using any building, but especially a residential building, is ensuring an adequate technical condition. Process of revitalization of residential buildings is connected with familiarity with the technical problems of passing. However, the secret of lasting is found, above all, in the propagation of aesthetics. The diagnosis of the technical condition is an initial stage of renovating historical buildings. Conclusions drawn from the diagnosis are a basis for planning revitalization works.
Jijo James, Archana James, Arun Kumar, Elumalai Gomthi and Karunakaran Kamal Prasath
This investigation focussed on the plasticity and swell-shrink behaviour of an expansive soil that was stabilized using electro kinetic stabilization (EKS) techniques with cationic fluids for enhancement of stabilization. 0.25 M solutions of calcium hydroxide and calcium chloride were used as cationic fluids. An electro kinetic (EK) cell of dimensions 500 mm x 150 mm x 160 mm with inert graphite electrodes of size 140 mm x 160 mm x 5 mm was adopted for the stabilization process, carried out at an applied voltage of 40 V over a period of 6 hours. After the duration of the test, stabilized soil sample was subjected to Atterberg limits and free swell tests to determine its plasticity and swell-shrink characteristics. The results of the investigation found that both fluids were capable of reducing the plasticity and swell-shrink behaviour of the soil with different levels of effectiveness.
Carbon accounting has become a valuable tool for expressing the fossil energy demand of products, organizational entities, or entire countries. About a decade ago, cities also began accounting their carbon emissions. The first major city to do so was London in 2009, stating a carbon footprint of 4.84 tCO2eq/(year*capita) for 2008. Nowadays, multiple rankings compare the carbon emissions of cities. For example, the Urban Land Magazine lists São Paulo as the city with the world’s lowest carbon emissions (1.4 CO2eq/(year*capita)). Such listings typically present the depicted emission values as scientifically indisputable numbers. However, a closer look at the applied methodology frequently reveals a wide range of implicit, often undisclosed assumptions at the foundation of the calculations. This paper analyses the uncertainties of carbon accounting on the city scale, using the example of the Red Sea resort town of El Gouna. The estimated value of El Gouna’s carbon footprint for the year 2014 is 14.3 tCO2eq/(year*capita). Third Scope emissions constitute the majority of El Gouna’s carbon footprint. Varying their underlying assumptions only slightly can lead to alterations of the results of more than 50%, questioning the robustness of the findings. To increase the robustness and the comparability of carbon accounting across cities, this paper suggests emphasizing Scope 1 and Scope 2 emissions, while limiting the role of Scope 3 emissions.