Abstract. Data used in order to determine the level of pollutants present in the air in Krakow came from three air quality monitoring stations located in Bulwarowa street, Bujaka street and Krasińskiego avenue. Based on these data, an analysis was performed concerning air quality in Krakow in 2010-2016. Also, a correlation analysis was performed to investigate the relation between air quality parameters and meteorological parameters, such as: wind, precipitation, temperature. An analysis of the results obtained showed that two factors are critical for the variability of air pollution in Krakow. The first of them is low-stack emissions from coal stoves and boilers. The other factor is the type of atmospheric circulation. It has been determined that the worst air quality occurs in the heating season as the prevailing circulation is anticyclonic (high-pressure) characterised by low temperature, lack or small amount of precipitation, weak wind and thermal inversion. The paper presents preventive measures aimed at reducing the amount of pollutants in Krakow. It has been found that in order to reduce the level of air pollution in Krakow, especially in the heating season, it is necessary to intensify operations aimed at eliminating coal and wood stoves and boilers.

Contemporary trends in the design, manufacturing and management of product development, including those connected with the Industry 4.0 are discussed. The development strategies of a new product in terms of market, product, technology are also presented. Tools and methods aiding the pro-ecological design and assessment of sustainable product development are described. As an example of product development modelling, there are presented models of the plastic cups production stages using the injection method before and after the identification of “hidden factories”.

In the paper, the authors focused on the environmental problems of pollution emissions caused by households using batch boilers fired with solid fuels. The aim of this study is to analyse the course of changes in the actual efficiency and emission of a solid fuel updraft boiler, the most popular type of batch boilers used in Poland in recent years. The subject of analysis is the comparison of the values of atmospheric emissions of harmful substances depending on the type of wood burnt in the boiler. The investigation comprises the combustion characteristics of three types of woody biomass (in billets), i.e., pine, birch, and beech. Based on the carried out research of all billets, the beech has the lowest values of CO (3497 mg/m3) and particulate matter (116.9 mg/m3). Despite this, obtained results exceed the current permissible limits based on the standard PN:EN 303-5:2012. The highest efficiency (54.13%) was obtained for birch billets, the lowest for pine (45.13%). The research has shown that the real heating efficiency during the combustion of wood, irrespective of the type of wood being burnt, is low. To summarise, the outdated installations contribute to air pollution several times higher, which indicates the need to replace inefficient heat sources using solid fuels with modern equipment that meets the most stringent standards.

Wood pellets play an important role among biomass materials used as fuel. At the same time, today’s economic, environmental, political and social realities, as well as other circumstances related to fuels used for heat generation, mean that there is demand for increasingly efficient and environmentally friendly combustion sources. As is well known, each combustion source has a different efficiency due to its intended use, design, principle of operation and the type and composition of the fuel burned. The amount of pollutants emitted into the environment during combustion also largely depends on these factors. The aim of this study was to compare the flue gas emissions and efficiency of two pellet burners of different design, burning certified A1 wood pellets from different suppliers. The emission requirements were met during the combustion of wood pellets in a boiler with the two burners tested (one with a moving grate and an overfed burner). The analyses and studies carried out aim to improve the capability of managing the efficiency and environmental performance of the heat source (i.e., a boiler or a burner) and the fuel (type of wood pellets). This is done in the context of demonstrating a better combustion source when selecting the right burner and fuel in terms of efficiency and emissions. In this paper, comparisons of flue gas emissions are presented along with characteristics in the form of graphs, as well as thermal and combustion efficiencies for the corresponding solid fuel used in the form of wood pellets. After comparing the emissions, it was found that the statistical averages of CO, NOx, dust and VOCs were similar for combustion at full power using the burners tested. Taking into account the pollution levels at combustion, it can be said that the difference in CO emissions at full and minimum combustion is lower for the experimental burner compared with the moving grate burner (reference burner). In summary, it can be concluded that the experimental overfed burner under consideration can be successfully used as a solid fuel boiler to burn wood pellets.

This paper focuses on the technical and practical aspects arising during the process of window production. One of the phases in the window manufacturing process is welding PVC corners. Therefore, the main subject is the flexural strength of PVC welds in the context of the required quality. In the first part of the paper, the authors highlighted the factors and conditions of the welding process and their influence on the final properties. In the next part of the study, attention is mainly paid to temperature control, which is often the cause of quality problems with welding corners. The welding process was conducted with the use of three types of welding machines, i.e. single-, double-and four-head units. In each case, the welding temperature was set in the controller of the machine; at the same time, the contact temperature measurement was taken. The next step was verification of the influence of temperature on the welded PVC corners by measuring the bending force according to PN-EN 514:2002. Additionally, the authors present the DIC (Digital Image Correlation) method used to assess displacements and strains for a selected case in the process of bending PVC corners. The study provides a basis for discussion and remarks about practical advice and identification problems associated with the durability of PVC welding in industrial processes.