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Abstract

The usefulness of untreated powdered eggshell as low-cost adsorbent for the removal of pentachlorophenol (PCP) from aqueous solutions was investigated. The most important parameters affecting the adsorption process, including the pH and ionic strength, were examined. The adsorption characteristics of PCP onto eggshell were evaluated in terms of kinetic and equilibrium parameters. The kinetic data were studied in terms of the pseudo-first order, pseudo-second order and intra-particle diffusion kinetic models. The equilibrium data were analyzed using the Langmuir, Freundlich, Sips and Redlich-Peterson isotherm models. The pseudo-second order model best described the adsorption kinetics. Using the Langmuir equation, the monolayer adsorption capacity of eggshell for PCP was found to be 0.127 mg/g. The results showed that PCP can be effectively removed from aqueous solution employing eggshell as a cheap adsorbent.

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Authors and Affiliations

Joanna Sadkowska
Jolanta Kumirska
Magda Caban
Mariusz Chmielewski
Piotr Stepnowski
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Abstract

This paper aims at presenting the possibilities of applying gas chromatography for the determination of pharmaceutical residues in different matrices. Section one of the study underscores the environmental advantages of employing GC for such analyses. Section two presents the innovative methods for determining pharmaceuticals in the environment. The last section discusses the results of the analysis of the GC and GC-MS market in Poland.

According to the literature data, the described methods were applied for the analysis of real samples: wastewaters, surface waters, soil samples. The samples were collected from the Pomerania region and the Gulf of Gdańsk. The pharmaceuticals were determined in various environmental samples. The highest concentrations were found in raw wastewater, medium – in a treated wastewater, and the lowest – in surface water. The most frequently detected pharmaceuticals were: ibuprofen, paracetamol, diclofenac and naproxen, all belonging to NSAIDs.

Furthermore, the results of the study of the Polish GC market indicate that a very limited number of entities are currently using chromatographic techniques, and pharmaceutical residues tests are exceptions, mainly due to the lack of the legal requirements in this field and the lack of own laboratories.

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Authors and Affiliations

Krzysztof Kuśmierek
Paulina Idźkiewicz
Andrzej Świątkowski
Lidia Dąbek
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Abstract

Nature reserves are one of the most important measures in saving biodiversity, however, during the climate change, a real danger arises, that these territories would not be able to fulfill the objectives. In order to mitigate negative effects of climate change in protected areas it is necessary to create and apply management programs, based on future ecosystems needs. The main aim of presented study was to evaluate sensitivity of rare and vulnerable species to climate change in order to suggest measures for better management of nature reserves in the future.

According to scientific literature, 12 biological and ecological plant characteristics determining sensitivity of species (limiting factors) have been detected. 73 plant species that are protected in Lithuanian reserves were evaluated qualitatively according to limiting factors of climate change. As the result, it was offered to apply additional protection measures to 47 species in the light of climate change. Groups of plant species that should be affected highly negatively or highly positively were identified. 16% of plant species protected in nature reserves were evaluated as very sensitive to climate change and the condition of these plants may worsen. On the other hand, 14 plant species were given as least sensitive to negative effects and future climate is more favorable to species growth and spread than the existing. The highest danger is predicted for Silene chlorantha (Willd.) Ehrh., and the best condition is predicted for Mentha longifolia (L.) Huds. Dactylorhiza incarnata (L.) Soó.

The study also gives recommendations for the protection of rare plants in the future. Different management measures are taken into account: mitigation of the direct effect of climate change (I), improvement of an existing level of rareness (II), respecting the relation to physical and biological environment (III), consideration of spread and geographical limits (IV). Three management intensity levels were suggested according to species sensitivity.

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Authors and Affiliations

Gytautas Ignatavicius
Monika Toleikiene
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Abstract

Anaerobic digestion is an important technology for the bio-based economy. The stability of the process is crucial for its successful implementation and depends on the structure and functional stability of the microbial community. In this study, the total microbial community was analyzed during mesophilic fermentation of sewage sludge in full-scale digesters.

The digesters operated at 34–35°C, and a mixture of primary and excess sludge at a ratio of 2:1 was added to the digesters at 550 m3/d, for a sludge load of 0.054 m3/(m3·d). The amount and composition of biogas were determined. The microbial structure of the biomass from the digesters was investigated with use of next-generation sequencing.

The percentage of methanogens in the biomass reached 21%, resulting in high quality biogas (over 61% methane content). The abundance of syntrophic bacteria was 4.47%, and stable methane production occurred at a Methanomicrobia to Synergistia ratio of 4.6:1.0. The two most numerous genera of methanogens (about 11% total) were Methanosaeta and Methanolinea, indicating that, at the low substrate loading in the digester, the acetoclastic and hydrogenotrophic paths of methane production were equally important. The high abundance of the order Bacteroidetes, including the class Cytophagia (11.6% of all sequences), indicated the high potential of the biomass for efficient degradation of lignocellulitic substances, and for degradation of protein and amino acids to acetate and ammonia.

This study sheds light on the ecology of microbial groups that are involved in mesophilic fermentation in mature, stably-performing microbiota in full-scale reactors fed with sewage sludge under low substrate loading.

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Authors and Affiliations

Piotr Świątczak
Agnieszka Cydzik-Kwiatkowska
Paulina Rusanowska
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Abstract

Pyrolysis is potentially an effective treatment of oily sludge for oil recovery, and the addition of a catalyst is expected to affect its pyrolysis behavior. In the present study, Fe/Al-pillared bentonite with various Fe/Al ratios as pyrolysis catalyst is prepared and characterized by XRD, N2 adsorption, and NH3-TPD. The integration of Al and Fe in the bentonite interlayers to form pillared clay is evidenced by increase in the basal spacing. As a result, a critical ratio of Fe/Al exists in the Fe/Al-pillared bentonite catalytic pyrolysis for oil recovery from the sludge. The oil yield increases with respect to increase in Fe/Al ratio of catalysts, then decreases with further increasing of Fe/Al ratio. The optimum oil yield using 2.0 wt% of Fe/Al 0.5-pillared bentonite as catalyst attains to 52.46% compared to 29.23% without catalyst addition in the present study. In addition, the addition of Fe/Al-pillared bentonite catalyst also improves the quality of pyrolysis-produced oil and promotes the formation of CH4. Fe/Al-pillared bentonite provides acid center in the inner surface, which is beneficial to the cracking reaction of oil molecules in pyrolysis process. The present work implies that Fe/Al-pillared bentonite as addictive holds great potential in industrial pyrolysis of oily sludge.

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Authors and Affiliations

Hanzhong Jia
Song Zhao
Xiehong Zhou
Chengtun Qu
Daidi Fan
Chuanyi Wang
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Abstract

The aim of the study was to evaluate the possibility of applying different methods of data mining to model the inflow of sewage into the municipal sewage treatment plant. Prediction models were elaborated using methods of support vector machines (SVM), random forests (RF), k-nearest neighbour (k-NN) and of Kernel regression (K). Data consisted of the time series of daily rainfalls, water level measurements in the clarified sewage recipient and the wastewater inflow into the Rzeszow city plant. Results indicate that the best models with one input delayed by 1 day were obtained using the k-NN method while the worst with the K method. For the models with two input variables and one explanatory one the smallest errors were obtained if model inputs were sewage inflow and rainfall data delayed by 1 day and the best fit is provided using RF method while the worst with the K method. In the case of models with three inputs and two explanatory variables, the best results were reported for the SVM and the worst for the K method. In the most of the modelling runs the smallest prediction errors are obtained using the SVM method and the biggest ones with the K method. In the case of the simplest model with one input delayed by 1 day the best results are provided using k-NN method and by the models with two inputs in two modelling runs the RF method appeared as the best.

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Authors and Affiliations

Bartosz Szeląg
Lidia Bartkiewicz
Jan Studziński
Krzysztof Barbusiński
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Abstract

Advanced automotive fleet repair facility wastewater treatment was investigated with Zero-Valent Iron/Hydrogen Peroxide (Air/ZVI/H2O2) process for different process parameters: ZVI and H2O2 doses, time, pH. The highest Chemical Oxygen Demand (COD) removal efficiency, 76%, was achieved for ZVI/H2O2 doses 4000/1900 mg/L, 120 min process time, pH 3.0. COD decreased from 933 to 227 mg/L. In optimal process conditions odor and color were also completely removed. COD removal efficiency was increasing with ZVI dose. Change pH value below and over 3.0 causes a rapid decrease in the treatment effectiveness. The Air/ZVI/H2O2 process kinetics can be described as d[COD]/dt = −a [COD]tm, where ‘t’ corresponds with time and ‘a’ and ‘m’ are constants that depend on the initial reagent concentrations. H2O2 influence on process effect was assessed. COD removal could be up to 40% (560 mg/L) for Air/ZVI process. The FeCl3 coagulation effect was also evaluated. The best coagulation results were obtained for 700 mg/L Fe3+ dose, that was slightly higher than dissolved Fe used in ZVI/H2O2 process. COD was decreased to 509 mg/L.

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Authors and Affiliations

Jan Paweł Bogacki
Hussein Al-Hazmi
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Abstract

In the study, environmetric methods were successfully performed a) to explore natural and anthropogenic controls on reservoir water quality, b) to investigate spatial and temporal differences in quality, and c) to determine quality variables discriminating three reservoirs in Izmir, Turkey. Results showed that overall water quality was mainly governed by “natural factors” in the whole region. A parameter that was the most important in contributing to water quality variation for one reservoir was not important for another. Between summer and winter periods, difference in arsenic concentrations were statistically significant in the Tahtalı, Ürkmez and iron concentrations were in the Balçova reservoirs. Observation of high/low levels in two seasons was explained by different processes as for instance, dilution from runoff at times of high flow seeped through soil and entered the river along with the rainwater run-off and adsorption. Three variables “boron, arsenic and sulphate” discriminated quality among Balçova & Tahtalı, Balçova & Ürkmez and two variables “zinc and arsenic” among the Tahtalı & Ürkmez reservoirs. The results illustrated the usefulness of multivariate statistical techniques to fingerprint pollution sources and investigate temporal/spatial variations in water quality.

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Authors and Affiliations

Hülya Boyacioglu
Hayal Boyacioglu
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Abstract

The research objective was to study temporal and spatial relations between specific phosphorus species as well as to examine total phosphorus content in the bottom sediments of an anthropogenic, hypertrophic limnic ecosystem Rybnik Reservoir, functioning under thermal pollution conditions. The chemical extraction procedure for the speciation of bioavailable phosphorus forms was used. It was found that available algae phosphorus was the most dominant phosphorus species in both sediment layers (83%), while the lower share was readily desorbed phosphorus form (0.1%). The phosphorus species concentrations depended on the organic matter concentration. The differences between phosphorus species contents in the upper (5 cm) and lower (15–20 cm) sediment core layers were low. The biologically active sediment layer extended from the sediment surface to at least 20 cm depth of the sediment core. Distributions of the concentrations within the year and at specific sampling points resulted from the variability observed for particular points and transformation intensity. Furthermore in the following study, the reaction rate constant for the increase and decrease in the concentrations of the phosphorus species in sediments was given. It was indicated that the speed of the phosphorus species transformations was affected by the environment temperature. In the heated water discharge zone (water temp. 17–35°C) the concentrations of selected speciation phosphorus forms increased more than in the dam zone (5–25°C). It was also found that the abundance of the bottom sediments with phosphorus species was related to the oblong and transverse asymmetry of reservoir depth.

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Authors and Affiliations

Maciej Kostecki
Malwina Tytła
Joanna Kernert
Katarzyna Stahl
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Abstract

The article presents research results of the introduction of powdery activated carbon to the existing technological system of the groundwater treatment stations in a laboratory, pilot plant and technical scale. The aim of the research was to reduce the content of organic compounds found in the treated water, which create toxic organic chlorine compounds (THM) after disinfection with chlorine. Nine types of powdery active carbons were tested in laboratory scale. The top two were selected for further study. Pilot plant scale research was carried out for the filter model using CWZ-30 and Norit Sa Super carbon. Reduction of the organic matter in relation to the existing content in the treated water reached about 30%. Research in technical scale using CWZ-30 carbon showed a lesser efficiency with respect to laboratory and pilot-plant scale studies. The organic matter decreased by 15%. Since filtration is the last process before the individual disinfection, an alternative solution is proposed, i.e. the second stage of filtration with a granular activated carbon bed, operating in combined sorption and biodegradation processes. The results of tests carried out in pilot scale were fully satisfactory with the effectiveness of 70–100%.

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Authors and Affiliations

Jadwiga Kaleta
Małgorzata Kida
Piotr Koszelnik
Dorota Papciak
Alicja Puszkarewicz
Barbara Tchórzewska-Cieślak
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Abstract

With the increase of agricultural production, residues of crop are the main source of organic matter in the soil and they are alternatives to inorganic fertilizers. For this purpose, effects of organic residues (cotton stalk, maize stalk, almond bark) commonly grown in Turkey were investigated for some soil microbial activity in clay soil. In this study, incubation experiment was set up. Five doses (0%, 2%, 4%, 6% and 8%) of organic residues (maize stalks, cotton stalks or almond bark) were applied to soil. Soil microbiological properties of soil samples such as CO2 respiration, dehydrogenase and urease activity were determined. According to the results obtained, maize stalk, cotton stalks and almond bark applications increased some soil microbiological activities, such as CO2 respiration, dehydrogenase and urease activities according to control soil. Maize stalk in comparison to other residues affects better on the biological properties of the soil. It is determined that enhancing effects of the added organic residues (maize stalk, cotton stalk, almond bark) into the soil were changed according to the type of organic residues, dosage and application terms.

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Authors and Affiliations

Çiğdem Küçük
Y.Tuba Tekgül

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