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1595 Uppsatser om Water load - Sida 29 av 107
Rening av avloppsvatten från biltvättar med filter av torv och inblandad kolaska : en utvärdering av effektivitet och avfallshantering ur ett miljöperspektiv
Filtermaterial av 75 % torv och 25 % kolaska har använts under 2 respektive 4 år för rening av avloppsvatten från två biltvättar. Jämförelse med Kristianstads kommuns riktvärden för avloppsvatten från fordonstvättar visar att filtren fungerat. För avfallsklassning krävs kunskap om innehåll av miljöfarliga ämnen i produkter som använts i tvätthallarna. I brist på kunskap om innehåll av ej analyserade miljöfarliga ämnen i filtren anses förbränning vara ett bra omhändertagande ur miljösynpunkt, då energi och aska återvinns..
Sticklingsetablering av Sedum spp. för gröna tak : biokol som organiskt material i substrat
The popularity of vegetated, or green roofs, has grown over the past years due to their potential
function of maintaining urban environment quality. The aim of this study was to investigate if
substrates with different organic material, peat and charcoal, with two contents (3 or 6 weight%)
influenced the growth of the cuttings during the first critical period of the establishment. Biochar is
used as amendment to agricultural soils and has, theoretically, many of the properties suitable as
organic content in green roof-substrates. Peat is one of the materials that is commercially used in
green roof industry. The substrate has been treated with different amounts of water.
Geokemisk undersökning vid Rävlidmyrgruvan, Västerbottens län : provtagning, analys och förslag till åtgärder
The mining industry, in terms of ore excavation and metal production, is and has been
important to the Swedish economy. In connection with the ore excavation process, large
amounts of partly sulphidic waste are produced. When the metal sulphides are exposed to air and water they are eventually oxidised, which leads to the formation of acidic water with high concentrations of metal cations and sulphate ions, so called Acid Mine Drainage
(AMD). This water may reach the nearest surroundings and cause negative environmental
effects. By covering the waste with soil or water, the oxidation process can be minimised.
At the Rävlidmyran mine in the county of Västerbotten open pit mining took place between
1951 and 1991.
Förstudie till våtmark i Rimbo : Design för optimal hydrologi och kväverening
The euthropthication of the Baltic Sea is a threat that is beginning to be taken seriously by the governments concerned. In Sweden, regulations concerning the allowed nitrogen (N) concentration in the effluent water from wastewater treatment plants are being tightened up. The Rimbo wastewater treatment plant has been imposed to reduce the annual mean concentration of total N in the effluent water to levels below 15 mg l-1. A more and more common way to reduce the nitrogen level in wastewater is to let the water pass through a wetland. This study investigates the possibility to build this kind of wetland at the outlet of the Rimbo wastewater treatment plant.A prestudy of the topography, soil characteristics and groundwater flow indicates that the land area in question is well suited for the construction of a wetland.
Båtbottenfärger innehållande TBTO : huvudsaklig källa till TBT i miljön
Antifouling paint containing the biocide bisTributyltinoxide (TBTO) has been used since1960 to reduce the occurrence of fouling on hulls on boats/ships. January 1st, 2003 theantifouling paints containing TBTO were prohibited. This ban covered all use of paintcontaining the substance TBTO. The ban was introduced because of alarming observationssuch as development of imposex in aquatic non-target organisms. Imposex is the impositionof male sexual characteristics on mainly female marine snails and occurs due to exposure toTributyltin (TBT).
Vattenlek i förskolan : Möjligheter till fysik i förskolan
The purpose of this study is to investigate witch knowledge and thoughts children will have about the term of floating and sinking, and witch possibilities there is to make various knowledge visible in preschool physics through playing with water. The study also concern the differences and similarities between two different groups of age who have participated in the study. The study was carried out by an activity with participant observation and feedback interviews afterwards. The result shows that the possibilities to physics are many in preschool. The children expressed new thoughts and ideas who concern other phenomena in physics during the investigation and discussed similar experiments and material to examine.
Beräkningsmodell för massbalanser för Slottshagens reningsverk
In the next few years the pollutants loading at the Slottshagen wastewater treatment plant in Norrköping is going to increase due to the reason that one of the waste water treatment plant in the district will be shut down.A survey of how these different pollutants are divided in the treatment process is therefore necessary for mapping out both the loading and treatment efficiency.This can be achieved by studying mass balances.Mass balances were carried out for the water treatment process for the mechanical/chemical,biological and the chemical stage.The mass balance studies show that the treatment efficiency was very good. However in order for the mass balances to be quite consistent and to ensure complete coverage of results and conclusions i.e. more reliable results, sludge samples should be collected and taken at different times per day and the influent rate should be investigated.In this work mass balance has been set up in order to illustrate and identify the factors that should be considered and taken care of for further estimation using mass balances in the future. Furthermore this survey results in a calculating model for the mass balances at thisplant.This calculating model is used as a tool to facilitate future calculations for mass balances for the water treatment process at Slottshagens wastewater treatment plant.Moreover it provides a basis for carrying out further estimation of the treatment process in the near future.In this project the importance of some operating parameters was also taken in consideration.This calculating model can be modified so that calculations of such operating parameters i.e. sludge loading and sludge age can be easily performed.Such information can be used further to evaluate different operation alternative in order to ensure an optimal use of the treatment process with in the plant..
Mätning av abrasivflöde för vattenskärningsmaskiner
The content of the following report is the summarized result of three students
thesis at Blekinge Institute of Technology in co-operation with Water Jet
Sweden AB.
This report will give the reader a description of principles how to measure the
abrasive mass flow in a waterjet cutting system.
The work began with a visit to Water Jet Sweden AB to get a closer look at the
problem. When the analysis of the problem was done the criteria were defined in
the form of demands and desires. The main task of the criteria was to guide the
search for the solution. The work proceeded with an extensive search for
abrasive flow meters along with obtaining information about flow measurement in
general. When the search for abrasive flow meters resulted in nothing all the
efforts were concentrated on finding a principle of measurement that could cope
with the criteria.
Förluster av nedströmsvandrande fisk vid turbinpassage : En fallstudie för att främja den småskaliga, såsom storskaliga vattenkraften
The expansion of the Swedish hydro power has contributed positively to the reduction of the environmental impacts from the fossil fueled power production. In the same time the extensive expansion has been proved to cause negative ecological and local environment impacts of a stream. This, in turn, has been affecting the biodiversity and fish stock negatively, which has been reduced. One of the underlying problems is the lack of possibility for the fish to pass the plants, but it is also directly correlated to the mortality rate of the fish passing through the turbine, which this study is investigating.The mortality rate has been computed for three different locations in Sweden, Untra, Tännfallet and a third one whose location is confidential, and is denoted as Case 1, 2 and 3. The model used to calculate the mortality rate in this investigation is based by existing blade strike models and knowledge and are investigating the death due to mechanical injuries from collision with a runner blade in the turbine.
Produktionsvåtmarker mot övergödning
In ambition to produce more and better harvests, artificial fertilizers are used to produce a better growth of crops in the agriculture landscape. This contributes to leakage of nutrients. Our forests also exhibit a leakage of nutrients. Air pollution contributes to more nutrients. High precipitation with high water flows as a consequence seems currently to occur more frequently in the county of Halland.
Undersökning av elkvalitet i distributionsnät med omfattande vindkraftselproduktion
The goal for this master thesis project has been to investigate the power quality in adistribution grid, which has a high fraction of dispersed power production due towindmills. The study has been done on a grid in Laholm South of Halmstad, whereapproximately 45 windmills are connected to the distribution grid owned by SHKEnergi. The investigation has been focused on to two radialy fed 20 kV lines, wheretwelve windmills are connected.Voltage variations have been studied by creating a model of the grid in the simulationprogram SIMPOW. The largest deviation that has been found in any point of the gridis ±1.9 % of the nominal voltage. This deviation is a result of varying powergeneration from the windmills and the voltage regulation at the connection point ofthe line.
Kinematisk och dynamisk modellering av den haptiska enheten TAU i sex frihetsgrader
The thesis presents an optimally designed kinematic structure for a new 6-DOF haptic devicebased on TAU configuration. The configuration of the TAU-2 proposed by Suleman Khan andKjell Andersson [1] was modified and its mobility was verified by using Grübler criterion tohave a 6 DOF. Analytical kinematic models for the inverse and forward kinematics weredeveloped for the haptic TAU configuration to determine a set of optimal design parameters.Kinematic performance indices such as volume of the workspace, kinematic isotropy and payload index, were defined based on the singular values of the Jacobian matrix. The Jacobianmatrix was scaled to homogenize the physical units. The Jacobian matrix dependent on theposition and orientation of the end-effector gives local isotropy and pay load index, so globaldesign indices were defined, which represent the performance of the mechanism in the wholeworkspace.
Legionella i tappvattensystem. Förekomst och förebyggnade-en redogörelse.
Legionella can be prevented, the question is how. This report is a degree in construction engineering education at Chalmers University in Gothenburg. A comprehensive written publication for Legionella-safe plumbing installations is not available and therefore requested. The purpose of this report is to present preventative measures against Legionella bacteria growth in tap water and in other systems where Legionella bacteria are a potential problem. Technical solutions are presented including how different systems function and what their advantages and disadvantages are.
Höjning av vattennivån i Mälaren : Ett hot mot Stockholms centrala delar vid en framtida klimatförändring?
In today?s World is climate change an important and hot topic. Climate scenarios for Sweden show a warmer climate, especially during the autumn, winter and spring. The same climate scenarios also show that the precipitation will increase during this part of the year, however, during the summer the opposite is expected to occur. The purpose of this essay is to examine how future climate change will affect Stockholm especially the expected increase in precipitation, which may lead to a rising level of the Lake Mälaren. During 2000/2001 was Stockholm hit by a flood. This flood nearly resulted in major consequences and showed that there were significant risks for the city of Stockholm and increasing precipitation will result in even more water in the drainage systems of Lake Mälaren. The results presented here show that it is important to increase the drainage capacity of Lake Mälaren in order to reduce the risks of flooding in the central parts of Stockholm.
End of line test : En studie av företaget Emotrons linjetestning i produktionen
Emotron is a company specialised in developing, producing and marketing equipment to con-trol, monitor and protect processes and machinery driven by electric motors, with an applica-tion focus. Examples of uses for their products are fans, pumps, lifts and cranes.The project is to look at Emotrons end of line test. The company has seen that at the final test-ing there is a bottleneck that restricts the outflow and prevents an increase in the number of tested products.The purpose of this project is to review how Emotrons end-of-line test works today and if there is a possibility to make the test more efficient in such a way that the quality is not at risk, while increasing the outflow of tested products.The projects first step is to look at and analyse what is causing the bottleneck at the end-of-line. When the analysis is complete, the next step is to review whether there is a possibility to solve the bottleneck and if so in what way can this be done. Emotrons most overall objective of the project is to increase the outflow of the number of tested products without jeopardizing the quality.An analysis has been made on frequency inverters, soft starters and shaft power monitors.