The article highlights the potential of brownfield areas in the sense of the rules and principles of sustainable development of the regions which shows significant disparities determined by the developmental tendencies of the socio-economic and environmental spheres, whose interactions were its basic platform in the Slovak Republic in the last years. Brownfield areas, with a degree of degradation and environmental quality depending on their type and original use, have a negative impact on all mentioned spheres of regional development, since such sites are unused and represent so-called brown investments, i.e. areas from which the region has no benefit. From the explicitly defined positive and negative determinants of the actual occurrence of brownfield areas in terms of sustainable development of the regions, the article quantifies their prioritization in the process of implementation into the regional development model, accepting the principles of Saaty matrix which is objective from a process perspective of sustainable regional development. Based on the explicit quantification of the above-mentioned determinants, the categorization of brownfield areas in the process of sustainable regional development, including the model of regional development with implemented brownfield sites, whose actual occurrence supports the occurrence of diversified activities, reduces the price of the surrounding land and ultimately threatens the health of the affected population and reduces the price of surrounding lands.

The paper deals with solutions of brownfields in Slovakia in the context of the regional development. It refers to the potential that brownfields have for the benefit of further development at not only local but also at regional level in order to create aesthetically and ecologically balanced environment and landscape. It also shows the interaction of revitalization and subsequent reuse of brownfields in order to minimize regional disparities in the territory of the Slovak Republic.

The identification of roof surfaces is characterized by a sequence of several processing steps. The boundary detection of different types of roof is realized from light detection and ranging (LiDAR) cloud points and can confirm the real boundary of the roof. In the process of processing LiDAR data, shortcomings have been found regarding the inappropriate classification of points (class 6 “buildings”) concerning the roofs (the points of the building facade were marked as outliers and reclassified). In cases of insufficient point density, there is a problem with not being able to capture either the roof boundary or small roof objects, along with the possible occurrence of gaps inside the roof areas. This study proposes a processing procedure in a geographic information system (GIS) environment that advocates the identification of roof surfaces based on the LiDAR point cloud. We created the contours of a roof surface boundary with a simplified regular shape. From 824 roofs in the studied area, six different types of roof were selected, which this study presents in detail. The expected result of the study is the generation of segments inside the roof boundary. The study also includes the visualization of the outcomes of the spatial analyses of the identified roof surfaces, which forms the basis for determining the potential of solar systems with respect to green roofs for the development of smart city buildings.

No abstract

Mineral resources are life and driving force of the European Union. It is gaining awareness not only in the EU dependent on imports, but also in the world. In the context of the growing population and the growing demands of economies for natural resources, this type of material management has a significant negative impact on the environment. The main aim of the study was to justify the model of circular economy on the national level, based on the disparities between the regions of Slovak republic. To meet the objective, mostly one-factor analysis was implemented. The circular model, which is based on the partial replacement of primary raw materials by secondary ones, should, on the one hand, limit the depletion of natural resources and, on the other hand, reduce the amount of waste produced. The presented work focuses on the issue of sustainable development, which is closely related to the circular economy, and then explains the circular economy model, including the differences from the linear arrangement and possible obstacles to its implementation for the specific conditions of the Slovak republic. From the results, it is clear that the proposed circular model would be helpful to improve the inefficiencies and disparities on the regional and national level.

In this study, the adsorption of Fe(III) from aqueous solution on zeolite and bentonite was investigated by combining batch adsorption technique, Atomic adsorption spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy analyses. Although iron is commonly found in water and is an essential bioelement, many industrial processes require efficient removal of iron from water. Two types of zeolite and two types of bentonite were used. The results showed that the maximum adsorption capacities for removal of Fe (III) by Zeolite Micro 20, Zeolite Micro 50, blue bentonite, and brown bentonite were 10.19, 9.73, 11.64, and 16.65 mg.g−1, respectively. Based on the X-ray photoelectron spectroscopy (XPS) and X-ray fluorescence (XRF) analyses of the raw samples and the solid residues after sorption at low and high initial Fe concentrations, the Fe content is different in the surface layer and in the bulk of the material. In the case of lower initial Fe concentration (200 mg.dm−3), more than 95% of Fe is adsorbed in the surface layer. In the case of higher initial Fe concentration (4000 mg.dm−3), only about 45% and 61% of Fe is adsorbent in the surface layer of zeolite and bentonite, respectively; the rest is adsorbed in deeper layers.

In recent years, the mining industry has achieved an important position in the national economy due to its increasing productivity. However, since 2000, there have been signs of a slowdown, resulting from the national and local conditions of the mining industry. It is for these reasons that we have concluded that this type of industry must be assessed not only from the economic but also from the national and regional sectors, because the performance of the mining industry is directly affected by the value of mineral deposits and the structure of other industries. The present paper aims to analyze the development of the mining industry in Slovakia, in comparison with similar development in chosen European Union countries. Slovakia has been considered as a country with mineral resources and mineral-based products representing an important part of Slovakia’s foreign trade, with the significant imported mineral resources including mainly mineral fuels and ore raw materials. The development of the mining industry is assessed from the economics through the growth rate of gross domestic product (GDP) and through the national aspect through the rate of growth of the national economy. The aspects are evaluated by the multi-criteria method Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), with which we evaluated the country with the best mining industry development. The results of detailed quantitative analyses of the selected indicators for mining industry development for individual European Union countries show a fluctuating trend during the observed period, which is characterized by development disparities. Such results can be used to determine raw material policies in the relevant countries.

The influence of membrane type on the permeate flux in microfiltration of two sorbents Bentonite a natural sorbent, montmorillonite based clay and Lewatit S1468 a synthetic sorbent, styrene-divinylbenzene based copolymer was studied. Two types of membranes, single-and multi-channel, both asymmetric inorganic ceramic membranes based on α-Al2O3, were used. The experimental data were obtained by continuous microfiltration equipment. According to the results use of multi-channel membrane has more advantages higher permeate flux, lower energy consumption, and lower flow rate than disadvantages longer time period to reach the steady state and higher pressure loss.