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Problem of Clogging in Drainage Systems in the Examples of the Zur and Podgaje Dams
PublikacjaDrainage plays an extremely important role in hydraulic structures, such as earth dams. Observations of drainage in hydraulic structures under various soil conditions indicate that the phenomenon of clogging can lead to a radical reduction in the efficiency of drainage, making it non-functional within a few years after construction. This article describes the problems of drainage clogging by iron oxide in the examples of the Zur...
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Operational problems of constructed wetland for landfill leachates treatment: case study
PublikacjaIn the paper the quality fluctuations of leachate from municipal landfill in Gdansk (Poland) over the last 5 years and evaluation of a wetland system designed for treatment of the leachate are discussed.The research has been conducted during the 5 years period. The constructed wetland for leachate treatment, consisting of 2 horizontal subsurface flow reed beds, working in parallel was built in 2001. In the period 2005-06 it underwent...
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OPERATIONAL PROBLEMS OF CONSTRUCTED WETLAND FOR LANDFILL LEACHATE TREATMENT: CASE STUDY
PublikacjaThe present paper discusses the quality fluctuations of leachate from municipal landfill in Gdansk (Poland) over the last 5 years and the evaluation of a wetland system designed for treatment of the leachate. The research has been conducted during a 5-year period. The constructed wetland for leachate treatment was built in 2001; it consists of 2 horizontal subsurface flow reed beds, working in parallel. In the period 2005–2006...
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Renowacja systemu drenażowego w elektrowni wodnej Podgaje
PublikacjaDysfunkcja systemów drenażowych jest najczęściej efektem kolmatacji, która powoduje "uszczelnienie" drenażu. W artykule przedstawiono problemy ze zjawiskiem cyklicznej kolmatacji drenaży w elektrowni wodnej Podgaje na rzece Gwdzie oraz przeprowadzoną w 2012 roku renowację systemu drenażowego.
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O problemie kolmatacji geowłóknin stosowanych w drenażach
PublikacjaSystemy drenażowe występujące przy obiektach drogowych są niezwykle istotnym elementem tych budowli. Jednym z materiałów, które obecnie powszechnie stosowane są w systemach drenażowych są geowłókniny. Ich zadaniem jest zabezpieczenie odwadnianego gruntu przed procesem sufozji, jak również ochrona drenażu przed zamuleniem przy jednoczesnym zachowaniu wodoprzepuszczalności. Typową trwałość drenażu, w zależności od rozwiązań, szacować...
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Biological hazards in low noise, poroelastic road surfaces
PublikacjaDrainage pavements as well as poroelastic pavements ("PERS") are a very efficient way to decrease traffic noise by reducing tire/road noise at the source as well as noise propagation over the road surface. Many noise generating mechanisms at the tire/road interface are very much reduced by road porosity (pipe resonance, "air pumping", Helmholtz resonance and the horn effect). A well-designed porous or poroelastic road surface may...
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Long-term operation of Kickuth-type constructed wetland applied to municipal wastewater treatment in temperate climate
PublikacjaThe purpose of this paper is to discuss the problem of changes of effectiveness of Kickuth-type constructed wetland with subsurface flow applied to domestic wastewater treatment. This study is based on an example of a wetland 3000 m2 in surface, serving 800 inhabitants, located in Poland. The results of chemical analysis showed that after an initial year of ‘start-up time’, the efficiency of pollutant removal gradually increased...
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Landfill leachate treatment at a pilot plant using hydrophyte systems
PublikacjaConstructed wetlands can provide an effective and economical solution to landfill leachate treatment. In the article the performance of a CW for leachate treatment, consisting of two horizontal flow constructed wetlands (HF-CW) beds, working at the municipal landfill in Gdansk-Szadolki in the period 2004-2005 is being discussed. The plant has been operating since 2001. Clogging problems and surface flow occurred in the system...
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Spetiation of organic matter in Vertical Flow Constructed Wetlands
PublikacjaThe object of the research were VFCWs which are a component of biological treatment of two hybrid hydrophyte systems located in Wieszyno and Wiklino, close to Słupsk, Poland. The facilities that are subject to analyses are unified in terms of structure (filtration material, depth of the bed and time of operation), but they differ in organic matter load, amounting respectively to: 8.0 gCOD/m2day and 31.0 gCOD/m2day.The intensity...
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Noise measurements on low noise pavements - problems with inhomogeneity of wearing course
PublikacjaDuring the last several years, when performing numerous CPX noise measurements on low noise pavements,significant inhomogeneity of the wearing course was observed in numerous cases. Similar problems were almost not existing regarding to the dense pavements.In general three main reasons of inhomogeneity can be defined. The first one are imperfections in technology of production of a asphalt mix or/and errors made already during...
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Nitrogen fraction fluctuation during wastewater treatment in a multistage treatment wetland
PublikacjaAlthough the size of pollutants discharged to a WWTP plays an important and often underestimated role in characterizing treat ability and hence the degree of contaminant removal of wastewater. From one hend In order to obtain efficient nitrogen removal in thedenitrification process, sufficient amounts of bioavailable carbon source should be ensured bur for the other hand in TWs, particulates from the wastewater are naturally trapped...
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The best porous asphalt pavement in Sweden so far
PublikacjaIn 2010 a double-layer porous asphalt concrete (DPAC) pavement was constructed in various versions on the E4 motorway through the Swedish city Huskvarna. As a result of a court decision the Swedish Transport Administration had to reduce noise emission by applying a low noise road surface that would reduce A-weighted noise levels by 5 dB, as an average. Earlier experience in Sweden indicated that it was possible to obtain a high...
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Acoustic lifecycle study of the double-layer porous asphalt on E4 in Huskvarna, Sweden
PublikacjaIn 2010 a double-layer porous asphalt concrete (DPAC) pavement was constructed on the E4 motorway through the Swedish city Huskvarna. Earlier experience in Sweden indicated that it was feasible to obtain a high initial noise reduction but due to the widespread use of studded tires in winter, clogging and ravelling created losses of around 2 dB per year, with an expected acoustical lifetime of only 3 years. However, the improved...
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Inhomogeneity of low-noise wearing courses evaluated by tire/road noise measurements using the close-proximity method
PublikacjaPerforming numerous analyses of tire/road noise measurements on low-noise pavements during the last several years, the authors observed significant inhomogeneity of the wearing course in numerous cases, while similar problems were almost non-existent when dense pavements were measured. Three main causes of low-noise pavement inhomogeneity can be defined. The first one is imperfections in the technology used for asphalt mix production...
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Treatment of landfill leachate by constructed wetlands: three case studies
PublikacjaThe performance of three CW systems treating landfill leachate, two located in northern Poland (Szadółki near Gdańsk and Gatka near Miastko) and one in southern Sweden (Örebro), is discussed. The CWs differ in size, hydraulic regime, type of hydrophytic plants and type of leachate pre-treatment before discharging to the CW. The CW in Szadółki consists of two parallel beds with sub-surface, horizontal flow of leachate (HSSF) planted...