The frequency of on-site systems for treatment of domestic wastewater is increasing with new residential development in both rural and low-density suburban areas. Subsurface flow constructed wetlands (SFCW) have emerged as a viable option to achieve advanced or secondary treatment of domestic wastewater. The pollutant removal efficiency in SFCW depends on design parameters. Many of these factors have been investigated while others such as aspect ratio, design of water inlet structure and method of dosing the wetland have yet to be fully examined. This study examined the effect of aspect ratio and header design on BOD5 removal efficiency as well as the impact of flow rate on flow distribution in a SFCW. An aspect ratio of 4:1 achieved 10% greater removal of organic matter than a 1:1 ratio. Tracer studies demonstrated that wetlands loaded at a constant rate of 3.8 L/min and 7.6 L/min experienced preferential flow. In addition, tracer studies showed wetlands with leaching chambers as headers failed to achieve equal flow distribution. An improvement in effluent water quality was achieved by replacing the leaching chamber for a perforated manifold as the inlet structure. This study demonstrated the importance of the careful selection of aspect ratio and means by which water is introduced to the wetland in the design of SFCW.

Abstract Purification techniques for leachate from composting activity - analysis in terms of ammonia nitrogen, total phosphorus and BOD Sofia Lundkvist Leachate from compost facilities has a large impact on the environment if is not properly cleaned. Water samples taken at Ragn-Sells compost facility at Dåva in Umeå have had problems with high amounts of BOD (biochemical oxygen demand), ammonia nitrogen and total phosphorus in their leachate and need to lower these. The aim of this work was to investigate the methods available for treatment of these substances, see if there is a variation depending on spring and autumn in the presence of substances in the leachate from Dåva, and to investigate whether there are methods that can complement Ragn-Sells existing facility for the purification of leachate. Water samples were used to test season-differences of BOD, ammonia nitrogen and total phosphorus. Furthermore, I did interviews with persons from other compost facilities around Sweden to identify alternative methods to reduce the amount of those three substances in leachate from Dåva. There were no clear pattern between measurements in spring and autumn, but the analysis from Dåva shows that there is a statistically significant negative correlation between ammonia nitrogen with average temperature. When the temperature drops the concentration of ammonia nitrogen increases. Further analysis shows that Dåvas existing system likely can be supplemented with additional steps to improve purification of BOD, ammonia nitrogen and total phosphorus, but the data I received was not enough to declare witch method works best for Ragn-Sells as the majority of the persons I came in contact with could not account for the measured values of the three substances.

In 1995, the Environment Agency for England and Wales developed urban runoff treatment wetlands at two selected locations in Outer London. The systems have been monitored for a wide range of parameters including heavy metals, suspended solids and BOD over a period of two years. Seven storm events were also monitored. The ability of micro-organisms, isolated from the rhizosphere of wetland plants collected at both systems, to tolerate and accumulate heavy metals has also been investigated. This study has demonstrated that constructed wetland treatment systems are capable of reducing the pollutant loadings associated with urban runoff, and that such systems can be successfully established within urban areas. During dry weather, pollutant concentrations and loadings were typically low and associated removal efficiencies highly variable. However, during storm events, pollutant loadings increased and removal efficiencies improved, with mean removal efficiencies of 71% for Pb and 81% for Cr at the Dagenham wetland. An exception to this was for suspended solids which showed an overall increase of 99% during storm events. Several design and operational issues have been identified and addressed during the course of the monitoring programme, and recommendations for the improved design and operation of urban runoff treatment wetland systems have been made. A range of micro-organisms, isolated from both wetland systems, were able to tolerate elevated Zn and Pb concentrations. Two strains (Beauveria bassiana and Rhodotorula mucilaginosa) were selected for further work. Both strains could accumulate Zn and Pb, with B. bassiana showing a high capacity to bind Pb (maximum concentration of 136mgPb/g cells dry weight). Comparison of the growth of B. bassiana at 4°C and 30°C suggested that processes of microbial metal accumulation may occur throughout the year in treatment wetlands. The presence of Pb inside hyphae of B. bassiana, associated with hyphae walls and in the surrounding medium was confirmed. This study has found that micro-organisms isolated from urban runoff treatment wetlands can tolerate and accumulate Zn and Pb, and the application of these results to wetland treatment processes is discussed.

Práce je zaměřena na poskytnutí srozumitelného a čtivého návodu k sestavení podnikatelského plánu nově vznikající společnosti. Teoretická část shrnuje obecné poznatky z dané oblasti. V praktické části je zpracován kompletní podnikatelský plán společnosti, jejímž cílem je v Čechách vytvořit a usadit se na zcela novém trhu, který bude charakteristický využitím nejnovějších zobrazovacích a ovládacích technologií v oblasti nočních zábavních podniků a barů.

Target of diploma thesis The Operating Point of the Centrifugal Pump was create program for analyze system of pumps, it would be an effective instrument at projection these systems. Program is divided into two parts: system characteristic and performance characteristic. Subject of this thesis is create pumps database, enter performance characteristics and succeeding working with them. Program enable regulation pump with change speed and cooperation two pumps, work in parallel or series. The result of program is project system of pumps on enter parameters with more economy work.

Gotland is famous around the world for its unique nature. The agriculture here has always been an important source of income and part of the identity of the island. But today the profession has low status and hard to survive. How can the interest for farming be increased? Gotlandsgården is an investigation about how the agriculture could develop. It strives to re-establish the status of the farmer profession and to become the node for the Gotland's farmers, inhabitants and the tourists.  an investigation about how the agriculture could develop. It strives to re-establish the status of the farmer profession and to become the node for the Gotland's farmers, inhabitants and the tourists. / Gotland är känt för sin fantastiska natur. Lantbruket här har alltid varit en viktig inkomskälla och har alltid varit en viktig del i Gotlands identitet. Idag har inte bondeyrket samma rykte som förr och det är svårt att få tillräckligt med elever till lantbruksskolan i Roma. Hur kan man öka intresset för yrket och Gotlands landsbygd. Det här projektet är en undersökning i hur man genom arkitektoniska tillägg kan skapa en grön nod för Gotlands gröna näringar och lantbruksskola och på det sättet blåsa nytt liv i landsbygden på Gotland.

<p> This thesis describes the study of plate vortex ring generators invented and developed by Latta and modified and constructed by E.S.Fox. The vortex ring generator has been applied to destratify and aerate a natural pond in this research. Experiments were conducted to mix and aerate a stagnant and stratified pond in a natural, outdoor setting. Mixing times, temperatures, dissolved oxygen, BOD, COD and pH were measured for each experiment trial. A fluctuating single plate vortex ring generator was constructed and used in four of the five experiments with the depth of the vortex ring plate varied to determine the effect on mixing and aeration. A final experiment used a dual plate vortex ring mixer to examine the advantages of multiple plates with regard to mixing and aeration as well.</p> <p> It was found that the single plate vortex ring generator with an operating range of 1 /2 to 4/5Hz effectively destratified and mixed the pond within a 12 hour mixing duration. The generator aerated the pond by establishing a flow pattern in the pond such that the water at the surface of the pond experienced increased contact with the atmospheric air thereby transferring oxygen to the water. The impact of atmospheric air temperature proved to be a significant factor as a heat source to the pond which affected the time taken to destratify the pond. The increased oxygen transferred to the pond increased dissolved oxygen in the pond. The microbial organisms present in the pond experienced increased activity due to the increased dissolved oxygen available in the water because of the mixing action provided by the vortex ring generator.</p> <p> The summary of calculated results for all five experiments with the vortex ring mixer is as follows: (Refer to page iv for chart). <p> On the basis of the experimental results it was determined that the vortex ring generator has a bright future as a tool to improve water quality in natural water courses.</p> / Thesis / Master of Engineering (ME)

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In theoretical part of this master thesis is analyzed USB 2.0 interface, including USB OTG. Mainly are described here properties which are good to know for USB device design. In brief is given here a structure of the FAT file system. Practical part contains design of OTG Device and it’s realization including implementation of libraries for communication via USB and for working with FAT file system.

Submitted thesis deal with study of aprotic electrolytes in order to increase the safety for use in lithno – ionts accumulators. Increase of safety is specified by measuring the flash point of each electrolytes, at the same time are evaluated also other parameters important for use in accumulators. For determine the window of temperatures where the electrolytes can work is measured by melting point. The melting point is measured by cryoscopy. From electrical properties is measured specific conductivity of the electrolyte.