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Number of results: 11
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Abstract

The study presents the results of the research into different phosphorus forms in the bottom sediments of anthropogenic limnic ecosystems i.e. the reservoirs of Pławniowice, Rybnik and Goczałkowice (SP). The bottom sediments of dam reservoirs were investigated by chemical extraction procedure for phosphorus forms. The lowest value of the mean AAP form percentage in the Pławniowice bottom sediments reflected the effect of reclamation with the hypolimnetic removal that had been conducted in the reservoir since 2003. The highest percentage of the RDP form (2%) was found in the Goczałkowice bottom sediments. The order of the specific speciation forms in the bottom sediments of the examined reservoirs was: Rybnik: AAP > EP > WDP > RDP; 4,630> 3,740 > 117 > 65 > 3.5 mgP/kg Pławniowice: AAP > EP > WDP > RDP; 916 > 783 > 107 > 15 > 1.4 mgP/kg Goczałkowice: AAP > WDP > EP > RDP; 686 > 628 > 51 > 7 > 0.14 mgP/kg The mutual correlations between the phosphorus speciation forms (AAP : EP : WDP : RDP) were as follows: Rybnik: 1,323 : 1,068 : 33 : 18 : 1; Pławniowice: 654 : 559 : 76 : 11 : 1; Goczałkowice: 4,900 : 4,485 : 364 : 50 : 1. The comparison of the mean concentration values for specific phosphorus forms in the bottom sediments of the three investigated reservoirs demonstrated that the Rybnik sediments had the highest contents of phosphorus. The contents in Pławniowice and Goczałkowice were 5-7 times lower
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Abstract

The study of groundwaters was carried out in two different forest ecosystems of Słowiński National Park: Vaccinio uliginosi-Betuletum pubescentis and Empetro nigri-Pinetum in the period of 2002-2005. Differences were found in the position of the groundwater table and in the concentrations of nitrogen and phosphorus compounds in the investigated forest associations. In the Vaccinio uliginosi-Betuletum pubescentis association the groundwater table was found on average at a depth of -73.3 cm, while in Empetro nigri-Pinetum at -90.2 cm. No statistically significant effect of precipitation on the position of the groundwater table was found in this study. Statistical calculations (U Mann-Whitney test) for groundwaters in the analyzed forest associations showed statistically significant differences in the dynamics of concentrations of total nitrogen (T-N), organic nitrogen (Norg.), nitrate nitrogen (N-NO3 ), total phosphorus (T-P), organic phosphorus (Porg.) and the level of groundwaters.
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Abstract

Phosphorus removal and recovery from domestic wastewater is urgent nowadays. A novel process of nutrients removal coupled with phosphorus recovery from domestic sewage was proposed and optimization of induced crystallization reaction was performed in this study. The results showed that 92.3% of phosphorus recovery via induced Hydroxyapatite crystallization was achieved at the optimum process parameters: reaction time of 80 min, seed crystal loads of 60 g/L, pH of 8.5, Ca/P mole ratio of 2.0 and 4.0 L/min aeration rate when the PO43--P concentration was 10 mg/L in the influent, displaying an excellent phosphorus recovery performance. Importantly, it was found that the effect of reaction temperature on induced Hydroxyapatite crystallization was slight, thus favoring practical application of phosphorus recovery method described in this study. From these results, the proposed method of induced HAP crystallization to recover phosphorus combined with nutrients removal can be an economical and effective technology, probably favoring the water pollution control and phosphate rock recycle.
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Abstract

The study included bituminous coal seams (30 samples coal from the Bogdanka and Chełm deposits) of the Lublin Formation, the most coal-bearing strata in the best developed and recognized in terms of mining parts of the Lublin Coal Basin in Poland. High phosphorus concentrations in coal of the Lublin Formation were found (1375 g/Mg) as well as P2O5 in coal ash (2.267 wt%). The phosphorus contents in coal and coal ash from the 385 and 391 coal seams in the area of the Lubelski Coal Bogdanka Mine and in the area of its SE neighbor is the highest (max. 2.644 wt. % in coal and 6.055 wt. % of P2O5 in coal ash). It has been shown that mineral matter effectively affects phosphorus contents in coal and coal ash. At the same time, phosphate minerals (probably apatite and crandallite) present in kaolinite aggregates of tonsteins contain the most of phosphorus and have the greatest impact on the average P content in the 382, 385, 387, and 391. The secondary source of phosphorus in these coal seams and main source of phosphorus in these coal deposits that do not contain mineral matter of pyroclastic origin (378, 389, 394) may be clay minerals, which absorbed phosphorus compounds derived from organic matter released during coalification. Phosphorus-rich ash from the combustion of the Lublin Formation coal tend to be environmentally beneficial to the environment and also useful for improving the soil quality. Due to the low degree of coalification and high content of phosphorus in coal, this coals of little use for coking.
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Abstract

The elemental composition and morphology of aerobic granules in sequencing batch reactors (GSBRs) treating high-nitrogen digester supernatant was investigated. The investigation particularly focused on the effect of the number of anoxic phases (one vs. two) in the cycle and the dose of external organics loading (450 mg COD/(L·cycle) vs. 540 mg COD/(L·cycle)) on granule characteristics. Granules in all reactors were formed of many single cells of rod and spherical bacteria. Addition of the second anoxic phase in the GSBR cycle resulted in enhanced settling properties of the granules of about 10.6% and at the same time decreased granule diameter of about 19.4%. The study showed that external organics loading was the deciding factor in the elemental composition of biomass. At 540 mg COD/(L·cycle) the granules contained more weight% of C, S and N, suggesting more volatile material in the granule structure. At lower organics loadings granules had the higher diameter of granules which limited the diffusion of oxygen and favored precipitation of mineral compounds in the granule interior. In this biomass higher content of Mg, P and Ca, was observed.
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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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Abstract

The paper presents the research results for the soils sampled from the area located in the eastern part of the Chodzieskie Lakes, between the Middle Noteć River Valley and the Wełna River Valley, the right tributary of the Warta River. The research involved 7 soil samples from the surface horizons, allocated to the cultivation of various plant species (cereals and vegetable crops). The following were determined in the soil material: the content of phytoavailable forms of selected heavy metals Zn, Cu, Pb, Ni, Fe and Mn, active and available to plants phosphorus against the activity of selected oxydo-reduction and hydrolytic enzymes. The soil under the vegetable crops showed a very high richness in phosphorus available to plants, which must have been related to an intensive fertilisation. There were identified relatively low contents of the available forms of the heavy metals investigated, the fact that points to their natural content in soil, which triggered the inhibition of neither the oxydo-reduction nor hydrolytic enzymes.
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Abstract

Organic carbon, nitrogen, and phosphorus in the soils of the High Arctic play an important role in the context of global warming, biodiversity, and richness of tundra vegetation. The main aim of the present study was to determine the content and spatial distribution of soil organic carbon (SOC), total nitrogen (N tot ), and total phosphorus (P tot ) in the surface horizons of Arctic soils obtained from the lower part of the Fuglebekken catchment in Spitsbergen as an example of a small non−glaciated catchment representing uplifted marine terraces of the Svalbard Archipelago. The obtained results indicate that surface soil horizons in the Fuglebekken catchment show considerable differences in content of SOC, N tot , and P tot . This mosaic is related to high variability of soil type, local hydrology, vegetation (type and quantity), and especially location of seabird nesting colony. The highest content of SOC, N tot , and P tot occurs in soil surface horizons obtained from sites fertilized by seabird guano and located along streams flowing from the direction of the seabird colony. The content of SOC, N tot , and P tot is strongly negatively correlated with distance from seabird colony indicating a strong influence of the birds on the fertility of the studied soils and indirectly on the accumulation of soil organic matter. The lowest content of SOC, N tot , and P tot occurs in soil surface horizons obtained from the lateral moraine of the Hansbreen glacier and from sites in the close vicinity of the lateral moraine. The content of N tot ,P tot , and SOC in soil surface horizons are strongly and positively correlated with one another, i.e. the higher the content of nutrients, the higher the content of SOC. The spatial distribution of SOC, N tot , and P tot in soils of the Hornsund area in SW Spitsbergen reflects the combined effects of severe climate conditions and periglacial processes. Seabirds play a crucial role in nutrient enrichment in these weakly developed soils.
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Abstract

Due to insufficient operation efficiency, the studied treatment plant has undergone modernization. The aim of this study was to assess whether this modernization improved quality of the STP effluent and water quality in the receiver. The research period of fifty months covered time before and after the modernization. Samples were collected in four sites – upstream and downstream of the STP and by the sewage discharge. Electrolytic conductivity, water temperature and pH were measured onsite. Chemical analyzes were based on ion chromatography and determined the concentration of NH4+, NO3-, NO2-, PO43-, TDS. Microbiological analysis comprised serial dilutions to assess the number of mesophilic and psychrophilic bacteria and membrane filtration to enumerate E. faecalis, total and fecal coliforms as well as total and fecal E. coli. Values of most analyzed parameters did not improve after the modernization, or improved for a very short period of time (NH4+), while some of them even increased, such as PO43-, total and thermotolerant coliforms and E. coli. The maximum value of thermotolerant E. coli reached nearly 7 million CFU/100 ml and was observed after modernization. Also at the sites situated downstream of the STP some of analyzed parameters increased. The conducted modernization did not improve the quality of treated sewage and even a further deterioration was observed. It could have been a result of rapidly growing number of tourists visiting the studied area, thus generating large amounts of sewage causing STP overload coupled with poor water and wastewater management. Significant percentage of unregistered tourists hinders proper assessment of the STP target efficiency.
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Abstract

A better understanding of phosphorus distribution in slag is necessary to develop an effective way to treat dephosphorization slag formed during steelmaking. Here, previous studies on the enrichment, separation, and recovery of phosphorus from dephosphorization slag are reviewed, along with their influencing factors. The results suggest that a proper heat treatment can promote the selective enrichment and growth of P-rich phases. Further, adding P2O5 and FetO facilitates phosphorus enrichment. Also, Ca3(PO4)2 is precipitated from slag containing 18 wt% P2O5. MnO and MgO in the slag barely affect the phosphorus recovery. In contrast, the addition of Al2O3 and TiO2 significantly affects phosphorus enrichment and magnetic separation. A phosphorus recovery rate of more than 70% is achieved with the addition of 10 wt% Al2O3 or 10 wt% TiO2. New phases (Na2Ca4(PO4)2SiO4, Na3PO4, and Ca5(PO4)3F) tend to be formed on the addition of Na2O and CaF2, which promote phosphorus enrichment. However, the addition of Na2O and CaF2 results in the incomplete separation of phosphorus and iron, as CaF2 and Na2O improve slag metallization and the magnetism of iron-rich phases.
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