Sökresultat:
1616 Uppsatser om Surface water - Sida 7 av 108
Solenergi : en lönsam investering för ett lantbruk?
A possible way to reduce pollution and slow down the process of global warming is to increase the usage of renewable energy sources. One of these renewable energy sources is solar power. With the aid of solar panels and solar cells the energy from the sun can be transformed into both heating and electricity. The requirement to use the sun in this fashion is a suitable surface, for example a big roof, an angle between 40-60 degrees and that the surface should be exposed to the south. Almost every farm meets these requirements.
Lakningsförsök med furubarksflis : en utredning om utsläpp av fenolföreningar samt metallsorption
The filters used today to purify water are often expensive and the need to find new filter materials is substantial. Studies of pine bark have shown that this is a material that may be used as an alternative to conventional filter materials, such as activated carbon. However, the study of pine bark has shown that a leakage of phenolic compounds may occur when using the material for water purification. Therefore, the purpose of this report is to investigate the release of phenols from pine bark, in order to evaluate the use of pine bark as a filter material. Another assignment is to investigate the amount of metals adsorbed by the filter material.
Hur mycket "mjölk" ska det vara i mjölken, och hur styr vi det?
In most countries, the dairy industry focuses on the volume of milk produced instead of its composition. This results in a high content of water and a lower proportion of fat and protein. A high proportion of water is not desirable when processing the milk into various dairy products like cheese, cream and milk powder. High water content also increases the costs for transport and storage, and also an unnecessary, albeit marginal, strains on the world?s water reservoir.
New Generation Surface treatment for tools : A preliminary study
The surface finishing technique called black oxidation is currently being used on thetool holders made of low alloyed tool steel produced by Sandvik Coromant. Blackoxidation isn?t considered a sufficient technique because it doesn?t make the toolholders look like the quality products that they actually are. The reasoning behind thisis that the tool holders can show signs of corrosion after prolonged storing times orin countries with high humidity and temperature. The corrosion doesn?t decrease thetool holders performance, but the customers might believe otherwise.
Frigörelse av fosfor från färskt, fryst och torkat växtmaterial : ett laboratorieförsök för att öka förståelsen för fosfordynamiken inom växtodlingen
Phosphorus is the single most potent contributor to eutrophication of freshwater and has also been shown to contribute to the toxic algae blooms in the Baltic sea. The
dynamics and paths of losses of phosphorus from arable lands are not fully understood.
It is known that phosphorus can be lost directly from plant material to water.
In studies where plant material has been subjected to several freeze-thaw cycles, large amounts of phosphorus have been lost. Most studies have been conducted
under field conditions, with many factors effecting the measured losses of phosphorus, such as weather and type of soil. This study was performed in a controlled environment without the presence of soil. Instead of soil, small glass beads were mixed with the plant materials in vessels, to make possible homogeneous leaching with water through the mixture of glass beads and plant materials.
In this study, clover, ryegrass and dry straw were cut to pieces, approximately 2 cm long.
Utveckling av en ytmonterad fördelningsmätare som underlag för individuell debitering av vattenförbrukning i fastigheter
The master thesis, conducted at Metrima AB, concerns the development of a non-intrusivedistribution meter as a basis for individual tap water billing in apartments.The project is conducted in response to the market interest in individual tap water billing inapartments as an answer to environmental concerns regarding water consumption. Due to thehigh installation cost of traditional water meters, a new method of determining waterconsumption, without having to cut water pipes, is proposed.The proposed method distributes the total water consumption for an apartment complex toindividual apartments according to distribution meters, measuring water run-time, in eachapartment. The water run-time is estimated by measuring the water pipe?s outward vibrationsand temperature changes.A test environment was established and a prototype built, using a tilt- and vibration sensor forvibration sensing and a precision temperature sensor to measure temperature changes. As bothsensors work well in the test environment, further testing was done in 3 apartments for aduration of 5 days.
Rationell riskanalys inom VA-verksamhet med avseende på säkerhet, hälsa, miljö och kvalitet
This master thesis is developed based on the desire of the water and sewage department in the municipality of Karlskrona. The department, which vouches for the quality of produced drinking water and sewage cleaning, was in need of help dealing with risk analysis.The water and sewage department is obliged to identify and assess risks according to Swedish legislation. However, no guides for this purpose regarding safety, health, environment and quality were available. The aim of this report was to accomplish a guideline for the performance of risk analysis within water and sewage plants. If the guideline is used, the requirements in the legislation will be obtained.
Grundvattnets geokemi vid Gladhammars gruvfält, Västervik. Effekter av äldre tiders kobolt- och kopparbrytning
The municipality of Västervik, with support from Envipro Miljöteknik AB, is carrying out a main study of the minefields at Gladhammar. Mining of iron, copper and cobalt under different periods from the 16th century until the end of the 19th century has led to discharges of metals to the lakes situated downstream. The aim of the main study is to investigate the possibilities to reduce the environmental load on the surrounding ground and water caused by heavy metals from the mine. The present report is a part of the main study. The aim of the work is to investigate the geochemistry of the groundwater.
Kvantifiering av föroreningstillskott från dagvatten inom skyddsområdet för Göta Älv : en simuleringsstudie med modellen SEWSYS
The river Göta Älv reaches between Vänern and Gothenburg and is the main raw water source for Gothenburg that supplies about 700 000 people with water. To protect and maintain a high water quality, continuously samples and water analyses are made throughout the river. In 1998 a protection area was founded between surte and Lärjeholm where the raw water intake is. This was made to increase the awareness of the importance to protect the water. However, there is a lot of contribution of untreated stormwater to Göta Älv within the protection area.Göteborg Water and Sewage Works commissioned this thesis where two areas, Tagene industrial area and Kärra residential area, with untreated stormwater outlets within the protection area are studied.
OTEC för Tarawa
Ocean Thermal Energy Conversion, OTEC, a technology using the temperature difference between cold deep seawater and warm Surface water, can extract the work in the form of electricity. OTEC gives also synergies of drinkable fresh water. The temperature difference has an impact on the efficiency of the technology, which means that the feasibility of OTEC is geographically limited. The project intends to explore the possibility of replacing the atoll Tarawa?s present electricity generation with an OTEC plant and to explore synergies. In the present situation all of Tarawa?s electricity is generated by fossil fuels.
Drainfill
Ocean Thermal Energy Conversion, OTEC, a technology using the temperature difference between cold deep seawater and warm Surface water, can extract the work in the form of electricity. OTEC gives also synergies of drinkable fresh water. The temperature difference has an impact on the efficiency of the technology, which means that the feasibility of OTEC is geographically limited. The project intends to explore the possibility of replacing the atoll Tarawa?s present electricity generation with an OTEC plant and to explore synergies. In the present situation all of Tarawa?s electricity is generated by fossil fuels.
Dynamisk massbalansmodellering av fosfor i Östersjön
During the past few years a vast amount of research has been done to increase the understanding of the complex ecosystem of the Baltic Sea. Modelling and simulations are important tools to increase knowledge of the system. A suitable model must be simple to use and the parameters and variables needed in the model must be easy to access.In this paper a dynamical mass-balance model, CoastMab, which is validated for smaller coastal areas, has been used to predict concentrations and transports of phosphorus in three large coastal areas - the Gulf of Finland, the Gulf of Gdansk and the Gulf of Riga. CoastMab uses ordinary differential equations to regulate inflow, outflow and internal flows. To reflect seasonal variations in temperature and different types of flows the model has a temporal resolution of a month.
Vidhäftning mellan prefabelement och pågjutningsbetong : Undersökning hur skrovligheten påverkar vidhäftningskapaciteten vid skjuvning
Self-compacting concrete has soon been around for a decade. Recently the prefabrication industry has started to use this fairly new concrete type in larger scales, mainly because of its distinctive properties. There are still certain areas that need to be thoroughly examined, such as bond capacity. There have been very few studies regarding shear capacity due to the fact that the procedure is complicated.This report will highlight a method to examine the shear capacity of different surfaces that have been prewetted as well as non-prewetted surfaces. The surface areas follow BBK 04?s and Eurocode 2?s demand for surface roughness. A smooth surface will be completed in order to confirm if the different shapes influence the bond strength by shear stress or not. The purpose of this essay is to measure the bond strength within the shear capacity as well as examine the impact it has on surface roughness and treatment for shear bond.The method used to identify the shear capacity is called L-shaped Push-Off Test.
Effect of vortex-processed water on tomato (Solanum lycopersicum) plants
This pilot study examined whether treatment with Vortex Process Technology (VPT) of the irrigation
water used on tomato (Solanum lycopersicum) plants had any effect on plant growth. In a block
experiment, with two blocks comprising 12 vases containing 1 L water and two tomato plantlets,
treatment in which, nutrient solution was based on Vortex-treated water was compared with an control
using untreated water. All vases were kept in a static aerated culture system in a daylight chamber for
four weeks. The results showed that the effect of the two blocks exceeded the effect of vortex
treatment in terms of leaf area and weight of fresh and dry matter. Plant height, stem width and
internodal length were significantly different in tomato plants grown in Vortex-processed water
compared with the untreated control.
Optimering av OTEC-system
Ocean Thermal Energy Conversion, OTEC, is a sustainable energy conversion technology that is not yet commercialized. OTEC is a technology that utilizes the temperature difference in oceans between the warm Surface water and the cold water at 1 000 m depth to run a Rankine Cycle. This technology can produce electricity and provide synergies like fresh water, air conditioning and aquaculture. A simulation program for three alternative OTEC systems has been created in order to decide which OTEC system is most profitable; closed, open or hybrid system. In this simulation a production cost analysis is performed in order to investigate and decide which one of the three systems that has the lowest production cost. The production cost analysis also analyzes if the profitability is affected by the size of the facility. After these analyzes, the most profitable of the three different OTEC-systems is expanded by an installation of solar collectors in order to see if the thermal efficiency is improved. The result shows that the most profitable system varies with the size of the facility.