The Effect of Publicly Available COVID-19 Information on the Functioning of Society, Businesses, Government and Local Institutions: A Case Study from Poland.

The COVID-19 pandemic has seriously affected many world regions' societies and economies. The pandemic and the restrictions introduced in response to it have impacted social behaviour and the operation of businesses in various ways. The present study aimed to verify the impact of information on the COVID-19 outbreak in Poland on the frequency with which residents of Rybnik and the surrounding areas chose to stay in their houses or apartments, as well as the functioning of businesses. The originality of the study lies in the use of mediation modelling, in which the following were used as variables describing the epidemic in Poland: new cases of SARS-CoV-2 infection in Poland; the number of deaths caused by SARS-CoV-2 infection in Poland; and the number of people quarantined due to the COVID-19 epidemic in Poland. On the other hand, data on tap water consumption were used as variables describing the frequency with which residents of Rybnik and the surrounding areas chose to stay in their houses or apartments, the operation of businesses in and around the city, and the operation of government and local government institutions. The study's conclusions confirm that publicly available information about the COVID-19 outbreak in Poland affected the frequency of residents of Rybnik and the surrounding areas staying in their houses or apartments as well as the functioning of businesses in Rybnik and the surrounding areas. The increasing number of people who died due to SARS-CoV-2 infection was associated with the limited functioning of government and local government institutions in and around Rybnik, which contributed to restrictions on the functioning of service industry companies in the city and surrounding areas.

Innovative Technological Approach for the Cyclic Nutrients Adsorption by Post-Digestion Sewage Sludge-Based Ash Co-Formed with Some Nanostructural Additives under a Circular Economy Framework.

This paper presents a new, innovative technological approach, in line with Circular Economy principles, to the effective management of sludge generated during municipal wastewater treatment processes and subsequently used for biogas production. This approach allows for optimal, functional, and controlled cascade-type biotechnological thermal conversion of carbon compounds present in sewage sludge, later in solid digestate residues (after biogas production), and finally in the ash structure (after incineration, purposefully dosed nanostructural additives make the production of a useful solid product possible, especially for cyclic adsorption and slow release of nutrients (N, P, K) in the soil). The idea is generally targeted at achieving an innovative conversion cycle under a Circular Economy framework. In particular, it is based on an energy carrier (methane biogas) and direct energy production. The functionalized combustion by-products can be advantageous in agriculture. The use of ashes with nanostructural additives (halloysite, kaolinite) from combustion of sewage sludge after the anaerobic fermentation as an adsorbent of selected nutrients important in agriculture (Na+, K+, NO3-, SO42-, PO43-, Cl-) was verified at laboratory scale. The tests were carried out both for pure ash and for the ash derived from combustion with the purposeful addition of kaolinite or halloysite. The equilibrium conditions for nitrate, potassium, sodium, phosphate(V), sulphate(VI), and chloride ions from aqueous solutions with the use of the three adsorbent structures were determined. The obtained innovative results were interpreted theoretically with adsorption isotherm models (Langmuir, Freundlich, Temkin, Jovanovic). The most spectacular and clearly favorable results related to the influence of nanostructural additives in the process of sludge combustion, and formation of sorption surfaces under high temperature conditions were identified in the case of sorption-based separation of phosphate(V) ions (an increase from 1.13% to 61.24% with the addition of kaolinite, and even up to 76.19% with addition of halloysite).

The Bioconversion of Sewage Sludge to Bio-Fuel: The Environmental and Economic Benefits.

This paper aims to analyze the economic feasibility of generating a novel, innovative biofuel-bioenergy-obtained from deposit bio-components by means of a pilot installation of sewage sludge bio-conversion. Fuel produced from sewage sludge biomass bears the potential of being considered a renewable energy source. In the present study, 23 bioconversion cycles were conducted taking into consideration the different contents, types of high carbohydrate additives, moisture content of the mixture as well as the shape of the bed elements. The biofuel was produced using post fermentation sewage sludge for industrial energy and heat generation. Based on the presented research it was concluded that the composite biofuel can be co-combusted with hard coal with the optimal percentage share within the range of 20-30% w/w. Sewage sludge stabilized by means of anaerobic digestion carried out in closed fermentation chambers is the final product. The average values of the CO2, CO, NO, NOx and SO2 concentrations in flue gas from co-combustion of a bioconversion product (20% w/w) and coal were 5.43%, 1903 ppm, 300 ppm, 303 ppm and 179 ppm, respectively. In total, within a period of 4.5 years of the plant operation, 1853 Mg of fuel was produced and successfully co-combusted with coal in a power plant. The research demonstrated that in the waste water treatment sector there exists energy potential in terms of calorific value which translates into tangible benefits both in the context of energy generation as well as environmental protection. Over 700,000 Mg of bio-sewage sludge is generated annually in Poland. According to findings of the study presented in the paper, the proposed solution could give 970,000 Mg of dry mass of biomass qualified as energy biomass replacing fossil fuels.

The wettability, mechanical and antimicrobial properties of polylactide/montmorillonite nanocomposite films.

The aim of this study was to evaluate the effect of the not activated (unmodified) montmorillonite (MMT) filler on the antibacterial properties of polymer nanocomposites with a biodegradable polylactide (PLA) matrix. The subject of research was selected to verify the reports on the lack of antibacterial properties of unmodified montmorillonite in nanocomposites and to investigate the potential conditions of their manufacturing which are decisive for the resulting properties. Evaluation of antibacterial and mechanical properties of both the starting materials and the obtained nanocomposites filled with layered silicates as well as the wettability of the materials, measured by a sitting drop method was made on samples in the form of a film. The results show that the surface wettability of the polymer nanocomposites did not exhibit significant change compared to the film of neat PLA. However, a significant improvement in the mechanical and antimicrobial properties of the nanocomposite films obtained in a specific solvent casting process of the nanocomposite preceded by exfoliation of the film in an ultrasonic homogenizer was demonstrated. The antibacterial activity against Gram-positive bacteria Staphylococcus aureus and Enterococcus faecalis was also observed, and, moreover, the montmorillonite-containing films revealed a zone of inhibition of bacterial growth when tested against the lactosepositive bacteria of the Enterobacteriaceae family, which are present in the waste water. The advantageous properties of the obtained PLA/MMT nanocomposites suggest that the unmodified montmorillonite may be potentially used as filler for polymer films in the packaging industry.