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Determination of Sorption Properties of Heavy Metals in Various Biosorbents

Abstract

Various techniques of determination of properties of physicochemical processes of heavy metal sorption in biosorbents were analysed. The methods of preparing and storing samples, conditions of experiment performance, as well as the methods of data interpretation were discussed. Two procedures of study were analysed: (1) in the static system of biosorbent-solution contact and (2) in the system of dynamic flow of solution. Copper cation sorption was studied. The effect of consecutive stages of the study on the quality of final results was shown. A high degree of uncertainty of the sorption capacity assessment was reported, which was dependent on the manner of conducting the study. The application of the pseudo-second order reaction model was substantiated to describe kinetics of cation-exchange sorption and the model of Langmuir isotherm to describe equilibria. The study conducted reveals that in order to perform comparative analyses, it is necessary to establish a joint concept of conducting studies and the interpretation of results.

Open access
Eco-Investments - Life Cycle Assessment of Different Scenarios of Biomass Combustion

Abstract

The article presents the results of life cycle assessment of different scenarios of biomass use to produce energy in a selected company. The study is made on the case of Lesaffre Polska S.A. and its facility in Wolczyn which is one of the most modern biomass plants in Central Europe. The company is one of the leaders of using the environmental criteria in its strategic decision-making. Its goal is to avoid any waste and to form its own circular business system. One of its recent investments is a biomass fired steam boiler that uses agricultural and woody biomass to produce energy. Previously, biomass was sold to power plant and co-fired with coal. The scope of the paper is to assess the actual change in the environmental impact of biomass use in the Wolczyn facility. For that purpose, the life cycle assessment is used with the ReCiPe endpoint indicator. The assessment is based on the comparison of two scenarios: one assuming the biomass combustion in a new boiler, and the second one, assuming co-firing biomass with coal. The results of the study show that the investment is making a significant difference as far as the overall environmental impact is. Through avoiding the co-firing related emissions the company makes a big step ahead towards the decrease of their environmental impacts. The analysis shows that the significant impact in the co-firing scenario is posed in such categories as fossil depletion, climate change with impacts on human health and on ecosystems, particulate matter formation and agricultural land occupation. In the biomass combustion scenario, the above categories are complemented with metal depletion, natural land transformation, urban land occupation and human toxicity categories but with 4 times decrease of the overall impact. The study also shows that the change of the combustion system makes the most significant difference, while all the other factors, like biomass cultivation and processing, biomass transport have much lesser impact.

Open access
Effect of pH on the Production of Volatile Fatty Acids in Dark Fermentation Process of Organic Waste

Abstract

The aim of this study was to investigate the effect of pH on the dark fermentation process of kitchen waste by specifying the composition of the volatile fatty acids (VFA), H2 and by drawing the carbon balance. Studies were carried out in 8 dm3 batch bioreactor in mesophilic conditions. The kitchen waste from the city of Lodz were used as a substrate. Based on the study, it was observed that most of the VFA was produced during the first two days of the process, while in the following days the production was diminished. The highest production of VFA (19.5 g/dm3) was obtained in the bioreactor, where the pH was 7 and 8. Analyzing the produced VFA it was observed that mostly the acetic and butyric acid had been produced. Most of acetic acid (over 70 %) was obtained in fermenter with pH 7 and 8. In contrast, most of the butyric acid (over 40 %) was in the bioreactor with a pH of 6. Production of H2 was in the range from 4.29 to 26.5 dm3, wherein the largest amount of H2 was created in the bioreactor with a pH of 6.

Open access
Importance of Endophytic Strains Pantoea agglomerans in the Biological Control of Rhizoctonia solani

Abstract

Antagonistic activity of microorganisms against phytopathogens is mainly the results of plants’ health improvement due to the inhibition of pathogens growth and the induction of plants resistance against diseases. The aim of the research was to determine antagonistic properties of Pantoea agglomerans against Rhizoctonia solani. The properties of two strains P. agglomerans BC17 and BC45 were assessed according to the following criteria: mycelial growth of R. solani in the presence of bacterial metabolites, an impact of P. agglomerans on the growth of sugar beet in the pots containing soil with and addition of R. solani and without it, the ability to produce indole-3-acetic acid (IAA). It has been recorded that antagonistic properties of tested strains are different. In the presence of metabolites of BC17 strains, the mycelial growth of R. solani was inhibited by 78 % and for the strain BC45 the value amounted 46 %. In the pot bioassay the number of infested plants growing in the soil inoculated with P. agglomerans and the pathogen was lower when compared with the pots containing R solani. A higher reduction of infested plants, amounting 23 %, was obtained for the strain BC17. Both strains had the ability to produce IAA - a plant hormone of the auxin class, in the presence of tryptophan and its absence in the medium. The highest concentration of IAA was recorded after 7 days of culturing in the supernatant obtained from the media containing 2000 μg/cm3 of tryptophan. For the strain BC17 the concentration of IAA marked in the post - culturing liquid amounted 71.57 μg/cm3, and for the BC45 strain it amounted over 80 μg/cm3. Obtained results prove that P. agglomerans may be used in the biological protection against phytopatogenic strains of R. solani.

Open access
New Approach for n-Hexadecane Biodegradation by Sol-Gel Entrapped Bacterial Cells

Abstract

In this study sol-gel hybrid materials in the system SiO2-chitosan (CS) - polyethylene glycol (PEG), as novel structures with potential application in bioremediation were investigated. The organic components - CS and PEG were used as structural modifiers for functionality improvement. The catabolic activity to n-hexadecane of Pseudomonas aeruginosa BN10 free and immobilized cells was estimated. The cell immobilization technique was employed to evaluate its efficiency on biodegradation and protective effect from high levels of hydrocarbons. The characteristics of obtained hybrid materials were investigated via X-ray Diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Atomic-force microscopy (AFM) analyses. The obtained results revealed that the organic part in the synthesized hybrids is important for microstructure and defined properties creation. The rate of n-hexadecane mineralization by the bacterial strain was influenced by variation in cell densities applied in the immobilization procedures. Semi-continuous processes with multiple xenobiotic supplies were carried out. The synthesized by the sol-gel method hybrid matrices proved to be suitable carriers for realizing an effective biodegradation process of n-hexadecane by Pseudomonas aeruginosa BN10. Biodegradation of 50 kg/m3 of n-hexadecane was realized by free cells. Significantly greater quantity (150 kg/m3) was mineralized for 15 active cycles by entrapped bacterial cells. Biodegradation process with gradual increase of xenobiotic concentration reaching 30 kg/m3 for 120 h was also accomplished.

Open access
A Novelhybrid Bio-System for Wastewater Treatment Using Algerian Agricultural Wastes

Abstract

The development of a new clean, easy to handle process with similar efficiency to that of the conventional process is one of the most important challenges in green chemistry investigation. In this study, a new hybrid process was investigated; coupling coagulation-flocculation with adsorption using abundant and natural bioproducts (Chitosan and Ammi visnaga). The Chitosan/Ammi visnaga (coagulation/adsorption) system was studied for its Brilliant Green dye removal capacity. This new technique seems to be a good alternative method for wastewater treatment, showing satisfactory results with high rates of elimination that range around 90 %.

Open access
Response of Pulses to Seed or Soil Application of Rhizobial Inoculants

Abstract

In micro-plot experiments growth, nodulation and seed yields of pea, yellow lupine and soybean grown in a soil colonized by high populations of pea and lupine rhizobia and low population of soybean rhizobia as influenced by seed or soil application of rhizobial inoculants were studied. The studied inoculation method had no significant effects on root nodule numbers, plant growth at the flowering stage and on seed yields of pea and yellow lupine in comparison to uninoculated control treatments. In the case of soybean seed and soil inoculation with soybean rhizobia (Bradyrhizobium japonicum) resulted in a significant increase of nodulation intensity, fresh and dry mass of shoots at the flowering stage as well as pod numbers and soybean seed yields at harvest. Soybean grown on plots in which soil was inoculated with the symbiotic bacteria gave seed yield by about 57 % higher as compared to that of soybean grown from seed inoculated with the rhizobia and by 169 % higher than when this crop was grown on the control (uninoculated) plots.

Open access
Surfactants in Klodnica River (Katowice, Poland). Part II. Quaternary Ammonium Compounds

Abstract

The paper presents methods of determination of analytes of the cation group (alkyl benzyl dimethyl ammonium (BDDA-C12-C16), alkyl trimethyl ammonium (TMA), hexadecyl piridinium (HP)) in surface water and bottom sediment samples. In the sample preparation phase the solid phase extraction (SPE) or accelerated solvent extraction/ultrasound assisted extraction (ASE/UAE)-SPE technique was used and in the identification phase and quantitative determination of analytes phase - ion chromatography technique (combined with a conductivity detector (CD)). The determined concentrations were in the range below the determined method detection limit (MDL) or method quantification limit (MQL) figures up to 0.142 ±0.023 mg/dm3 or 2014 ±10 μg/kg (liquid and solid samples, respectively). Comparing concentrations of individual analytes found in liquid and solid environmental samples we may notice that surfactants containing a shorter alkyl chain in their molecules were found in higher concentrations in liquid samples (hydrophobicity increasing with the chain length).

Open access
Sustainability of Waste Materials in Affinity with Ecologically Sustainable Development: A Case Study of Kosovo

Abstract

Using our natural resources, we produce much waste that can be recycled as a useful resource, which further contributes to climate change. Kosovo, generally produces a huge amount of waste, particularly Prishtina as the capital its capital city. The study presented in this paper investigated the high-rise buildings in Ulpiana neighbourhood of the city of Prishtina and waste disposals in Kosovo, focusing on the challenges of urban waste management, particularly on the recycling of high-rise urban generated waste. The research methods consist of empirical observation through urban spatial zone. Researched model of high-rise buildings, surveyed the land use, and recycling process of a total generated waste of 778.8 kg daily/per one structure. According to the conceptual and calculated findings strengthened with awareness for sustainable consumption, and proper urban strategy for implementing the recycling waste materials, it is indicated that the waste amount can be decreased and recycled for about 25 % from the total waste generated daily.

Open access
The Variability of the Concentration of Bioaerosols Above the Chambers of Biological Wastewater Treatment

Abstract

The article presents the results of research over microorganisms (psychrophilic and mesophilic bacteria and microscopic fungi) found in wastewater in denitrification and nitrification chambers and specifies the proportion of these microorganisms in bioaerosol at various levels above wastewater level (20, 50 and 100 cm). In the denitrification chamber (anoxic) in 1 cm3 of sewage there were on average 30.35 · 106 CFU of mesophilic bacteria, 72.88 · 106 CFU of psychrophilic bacteria, and 37.3 · 105 CFU of microscopic fungi. In the nitrification chamber, where the oxygen concentration ranged from 0.37 to 2.32 mg O2·dm−3 of wastewater, the number of microorganisms was lower. In 1 cm3 of wastewater there were on average 20.2 · 106 CFU of mesophilic bacteria, 51.76 · 106 CFU of psychrophilic bacteria, and 15.22 · 105 CFU of microscopic fungi. In sewage bioaerosols above these chambers, higher numbers of psychrophilic bacteria than mesophilic ones and microscopic fungi were reported. At the same time differences in the number of microorganisms at different heights above the surface of wastewater could be observed in bioaerosol, as well as between the chambers of the bioreactor. It was found that most frequently the amount of microorganisms decreased with height. The percentage emission ratio (ER) of microorganisms in bioaerosols coming from wastewater accounted for only a fraction of a percent and ranged from 1.13 · 10−8 % (microscopic fungi over the denitrification chamber) to 24.53 · 10−9 % (psychrophilic bacteria over the denitrification chamber). It was found that the process of mixing, aeration of wastewater, have an effect on the emission of microorganisms.

Open access