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Abstrakt

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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Abstrakt

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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Abstrakt

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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