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Abstract

The aim of the study was to evaluate the drug resistance of Enterococcus faecalis and Enterococcus faecium isolated from different types of poultry waste. The study material consisted of feather samples (duck, turkey, chicken), sludge and centrifuge sediment, originating from three poultry farms. The study was conducted in two stages; isolation and identification of Enterococcus bacteria from the waste and evaluation of their drug resistance using Kirby-Bauer method. Contamination of the poultry waste with Enterococcus isolates included E. faecium species (79 %) and E. faecalis (21 %). The most contaminated were sludge and sediment from the centrifuge as well as chicken feathers, irrespective of the place and time of sampling. Tested isolates showed multiple resistance and similar reaction to all antibiotics used in the study and E. faecalis strain was more resistant. Enterococcus isolates showed the highest resistance to streptogramins, carbapenems, fluoroquinones, aminoglycosides and penicillins, and the lowest for nitrofurantions and phenicols.

Abstract

Zero-valent iron is very effective in the treatment of groundwater contaminated with chlorinated hydrocarbons and solvents broadly used in industrial production. In terms of its sustainability and cost, a legitimate effort has been devoted to the optimization of the remediation process, which can be demanding and expensive. In this study, the application potential and fundamental properties of several commercial micro-sized zero-valent iron (μZVI) were investigated. Although the manufacturers report the basic parameters of μZVI, it has been shown that the actual reactivity of apparently similar products varies notably. This work was focused on monitoring of frequently occurring contaminants. The actual contaminated water from the Pisecna locality -former landfill of industrial waste, with high levels of chlorinated ethenes and ethanes (PCE, TCE, cis-1,2-DCE and 1,2-DCA) was used for the experiment. The degree of dechlorination reached over 85 % 32 days after the application of μZVI in several samples and a far higher reaction rate for smaller particles was observed. Also, the amount of cis-1,2-DCE, which is characterized by slow decomposition, decreased by more than 95 % over the course of the experiment. Smaller particles showed a much longer sedimentation rate and gradual fractionation was also observed. Monitoring of ORP and pH also suggested that the smaller particles possessed a reduction capacity that was sufficiently high even at the end of the experiment. Laboratory tests with apparently similar μZVI samples indicated considerable differences in their reaction rate and efficiency.

Abstract

In the present era of continually increasing energy demand, Europe faces many challenges, such as high and unstable energy prices, growing global energy demand, increasing threat of climate change, sluggish progress within energy efficiency and issues related to increasing demand for the use of renewable energy sources. It is desirable to seek opportunities to use energy consumed most reasonably, thus ensuring continuous improvement of energy efficiency in the industry. The scope of the research includes reviewing studies in this matter and analysing the most beneficial solutions for the plant. The work aims to assess possible undertakings to modernise the energy management of an industrial plant on the example of Bulten Poland S.A. rationally and profitably for the plant. The work contains an analysis of the profitability of the potentially most beneficial solutions in terms of improving the energy efficiency of the plant. Mentioned in the article solutions, aiming increasing energy efficiency, helped become the plant independent within heating up facilities. Total heat recovery potential in amount of 18 965 GJ is motivation for further activities. This is a great opportunity to reduce significantly carbon footprint (replacing lightening into LED technology reduced CO2 by 206.3 Mg/year) and be more competitive on the market by reducing costs of product.

Abstract

As the urbanisation level increases, due to intensification of car traffic and increased areas of impermeable surfaces, pollution of surface wastewater and a negative impact on water bodies are increasing. Due to the increasing pollution of surface water bodies, the eutrophication process is taking place intensively. One of the technologies of surface wastewater treatment allowing reduction in the amounts of suspended solids (SS), heavy metals and other pollutants is surface wastewater filters. Filters with different fillers have been designed for the treatment of principal surface wastewater pollutants: suspended solids, heavy metals (zinc, cadmium, copper, lead), BOD5, total carbon and nitrogen. The Kriging method was adapted to test the efficiency of filters filled with construction waste and wood waste-derived biochar using distance matrices. The method developed makes it possible to model the characteristics of filters in relation to different fillers, using experimental results. The mathematical model is suitable for other filtrate characteristics, not only the ratio of fillers, but also the length of the filter life, its durability calculations, which allows optimizing filter cleaning efficiency up to 96.93 %.

Abstract

The biosorption of lithium from batch systems by Arthrospira (Spirulina) platensis biomass was studied. Adsorption capacity of the biosorbent was investigated as a function of contact time, initial metals concentration and pH values. Lithium content in biomass was determined using Proton Induced Gamma Emission technique. The ability of spirulina biomass for lithium biosorption showed a maximum at the pH = 11. Equilibrium data fitted well with the Langmuir model with maximum adsorption capacity of 1.75 mg/g, while the kinetic data were best described using the pseudo second-order kinetic model. The IR spectrum of the Li-loaded biomass revealed that lithium ions could be primarily bind to –OH, –COOH, –NH, –NH2, and –NH3 groups present on biosorbent surface. Arthrospira platensis biomass could be applied as environmentally friendly sorbent for lithium removal from wastewater.

Abstract

Weather conditions prevailing in Poland often cause that meadow sward designated for silage is harvested too late, which decreases the quality of prepared silage. The aim of the research was to assess the quality of silages from dried meadow sward. The silages were ensiled in large cylindrical bales in selected individual farms specializing in milk production. The farms where the research was carried out were located in three voivodeships: slaskie, malopolskie and podkarpackie. In the prepared plant material, the basic chemical composition was determined using the method. When comparing the mean values, it was established that silages from the investigated region had a favourable content of total protein, the highest concentration was recorded for silages from Slask, followed by Malopolska and Podkarpacie. A slightly elevated concentration of crude fibre, fraction of acid detergent fibre (ADF) and neutral detergent fibre (NDF), was recorded. This fact shows that farmers collect raw material, particularly from the first cut, too late. Nutrient value of silages from meadow sward decreases with progressing vegetation. Higher protein and energy losses during sward ensiling were also observed at considerable drying of the plant material. In most cases, silages from the studied farms had a low content of monosaccharides. The carried out chemical analyses showed that in overall assessment the studied silages are of good quality; silages prepared from meadow sward from the third cut had the highest value. Proper technology of preservation of meadow sward is one of important factors in the production of feed for ruminants.

Abstract

The use of oil fly ash after the recovery of heavy valuable metals was investigated. More specifically, its use, as an adsorbent of dyes from industrial wastewater, was evaluated. Methylene blue was used as a model compound to study the adsorption capacity of the proposed carbonaceous residue from metal recovery treatments. The effects of contact time, initial dye concentration, and absorbent dose were investigated. The maximum amount of dye was adsorbed after one hour. Moreover, 1-3 g of residues were necessary for the removal of 200-1000 mg dm–3 from 0.050 dm3 of contacted solution. The Langmuir isotherm model was in good agreement with the adsorption equilibrium data, indicating a maximum monolayer saturation capacity of approximately 40 mg/g at 25 °C. High abatement efficiencies (up to 99 %) were obtained, and the adsorbed dye was released almost immediately by re-contacting with water. The adsorption capacity was at least four times lower than that of commercially available active carbon. The double treatment of oil fly ash with deionised water and hydrochloric acid allows for the extraction of over 85 % of the vanadium, iron, and nickel content in the ash. However, the negligible or zero cost of solid residues, otherwise disposed in landfills, indicates their potential as a valid alternative. The use of oil fly ash for both recovery of heavy valuable metals and the subsequent removal of dyes from wastewater suggest a zero-waste process.

Abstract

Tamazert kaolin was modified with dimethyl sulfoxide (DMSO). The starting material and resulting from the intercalation were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy (SEM). Intercalation caused considerable changes in our clay by increasing the basal spacing to 11.22 Å, an intercalation rate of 98 %. The adsorption of methylene blue was studied as a function of pH, contact time, temperature, dye concentrations and adsorbents. Kinetic data have been adequately described by the pseudo-second order and intraparticle scattering model. The adsorption isotherm is in good agreement with the Redlich-Peterson model. A change in thermodynamic values (ΔH°, ΔS° and ΔG°) was observed after intercalation. Adsorption became non-spontaneous exothermic and ordered.

Abstract

In the year 2016, passive biomonitoring studies were conducted in the forest areas of southern and north-eastern Poland: the Karkonosze Mountains (Kark), the Beskidy Mountains (Beskid), Borecka Forest (P. Bor), Knyszynska Forest (P. Kny), and Białowieza Forest (P. Bia). This study used bark from the tree, Betula pendula Roth. Samples were collected in spring (Sp), summer (Su), and autumn (Au). Concentrations of Mn, Fe, Ni, Cu, Zn, Cd, and Pb were determined for the samples using the atomic absorption spectrometry method with flame excitation (F-AAS). Based on the obtained results, the studied areas were ranked according to level of heavy-metal deposition: forests of southern Poland > forests of north-eastern Poland. Some seasonal changes in the concentrations of metals accumulated in bark were also indicated, which is directly related to their changing concentrations in the air during the calendar year, for instance, the winter heating season produces higher concentrations of heavy metals in the bark samples taken in spring. When deciding to do biomonitoring studies using bark, but also other biological materials, it is necessary to take into account the period in which the conducted research is done and the time when the samples are taken for analysis, because this will have a significant impact on the obtained results.

Abstract

The present study was conducted to highlight the elemental composition of ten soil samples collected at different depths along of a soil profile (0.25-17 m). The collected samples were subjected to epithermal neutron activation analysis at the pulsed reactor IBR-2 of Frank Laboratory of Neutron Physics - Joint Institute for Nuclear Research - Dubna - Russian Federation. The concentrations in mg/kg of 36 major and trace elements were determined. Symbatic behaviour of geochemically related elements was observed: Th and U; Cl and Br and Fe, Ti, Ca, Al, and Mg, etc. A sharp increase of certain concentrations at the depth of 8 m was observed. Significant mafic sources of elements were observed and mostly are attributed to Ethiopian High Plateau with small amount of felsic volcanic rocks.