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8191 Uppsatser om Water management - Sida 13 av 547

Förändringar i markanvändning över tid och dess påverkan på vattenkvalitet

The EU Water Framework Directive has led that management follows the boundaries of natural catchments.The Swedish waters suffer from a nutrient overload that originates mainly from diffuse sources such as agriculture and the subcatchment of Hackstabäcken in Vallentuna Kommun, just north of Stockholm, has been chosen for this study because of its high nutrient load and because it has undergone obvious changes in land use through the years.In this study, the land use in 1902 is compared with the land use in 2011 in order to investigate if it has influenced the ability of the landscape to produce ecosystem services related to nutrient removal. These services will continue to be produced as long as the system is stable and resilient, but when landuse changes and manure from horses increases it will lead to disturbances that can convert a system from one regime in to a completely different one. That will result in loss, or degradation, of ecosystem services such as denitrification, phosphor sedimentation and adsorption, vegetation uptake and infiltration.The results of this study are based upon area calculations of landuse from old maps from 1902 and 2011. Through these maps it becomes clear that the forests in Hackstabäcken, has increased with 170 ha together with an urbanization of 311 ha, at the same time as wetlands and arable land has diminished and lakes has suffered from reductions. Wetlands have been reduced with 76 ha and the ones remaining are of insufficient quality from a nutrient removal perspective.Data from 1902 and 2011 regarding number of horses and bovines indicated a decrease in bovines and an increase in horses.

Förutsättningarna för ett parallellt generation IV system vid svensk nybyggnation av kärnkraft.

A new build in the Swedish nuclear power system would entail increased re-quirements for the proposed repository, which is adapted after the reactors of today. With a fast reactor, capable of burning nuclear waste, operating in parallel with the light water reactors, the increased requirements on the repository could be reduced.In this thesis, simulations of a light water reactor and a fast reactor have been performed by using the Monte Carlo code Serpent to investigate the changes in the fuel inventory. The light water reactor in the study is a boiling water reactor and the fast reactor of the type sodium-cooled fast reactor and they have been used for three different operation scenarios.By studying the fuel composition and the results from the simulations of the three scenarios conclusions can be drawn. Conclusions regarding the change of the fuel inventory and decay heat in Clab as well as the interim storage facility and in the repository. Depending on the operation alternative the changes dif-fered significantly and especially regarding the mass of burned actinides for different fuels in the fast reactor.The lowest increase of fuel assemblies was meet when using 50 years old fuel with 20MWd/kg U burnout and 2,0 % enrichment for start up of the fast reactor and 30 years old fuel assemblies with 50MWd/kg U burnout and 4,7 % enrichment for the further operation of the reactor.The increase of the number of fuel assemblies was 3174, which is equivalent to 641tons of heavy metal.

Projektering av småhus med solvärme som huvudkälla

In this report a study has been done regarding different heating systems on which are the mostcomprehensive with solar heating systems. The report has also been focusing if solar power can beused as a primary heating source for supplying more than 50 % of the buildings total heatingproduction. The University of Dalarna constructed a demo-house for this purpose and according tocalculations the total solar usage is more than 50 %. This house has been made for referenceregarding the design of the heating system of property 5:37.Further studies have been made to compare different heating systems that are compatible with asolar system, where the compared systems purpose is to be independent of direct using electricity. Asystem of this design is regarded as sustainable according to environmental as economic issues.

Vattenhantering och reglering för textilproducenter i Turkiet

Vatten är en av jordens livsviktiga resurser, en resurs som hela tiden minskar. I delar av världen råder akut vattenbrist och ofta återfinns industrier med hög vattenanvändning i områden med begränsad vattentillgång. En av dessa industrier är textilindustrin. Vid textil beredning är vattenförbrukningen mycket hög och avloppsvattnet är ofta mycket förorenat. Vattenfrågorna inom textil produktion har fram till idag inte uppmärksammats i lika stor grad som arbetsrätts- och kemikaliefrågorna.

Avbördningsekvationer för sjöar utan vattenföringsmätningar

Stage-discharge equations for lakes without disharge measurementsSimon AnderssonIn 2015 all lakes, rivers, coastal water and groundwater should be of good ecological statusaccording to the water framework directive from the European Union. In the process ofimproving the quality of Swedish water bodies, knowledge of where problems occur isneeded in order to utilize the resources optimally. The ability of lakes to store water is animportant factor since it controls the flow of water through the country. A stage-dischargeequation is a mathematical relation between discharge from a lake and its water level. Bybetter understanding of stage-discharge equations for lakes, their storage capacity can bedescribed better in hydrological models.This master thesis aims to evaluate methods for determining stage-discharge equations forlakes where a variable amount of field measurements is available.

Aktivt system för tidvattenreglering av Lysekilsprojektets vågkraftsteknik

This report investigates a possible solution to the problem with adapting wave powerplants to work in countries with tidal water. The wire connecting the buoy at the surface with the generator at the bottom needs to adjust to the varying water depth. Our solution to this problem is to attach the wire to a jack which is then placed inside the buoy. The jack is then powered by an electric engine. The report discuss what forces the buoy will be exposed to and then the structural integrity of the design is evaluated through simulations.

ENERGIÅTERVINNING I GRANSHOT® - PROCESSEN

Uvån Hagfors Teknologi AB (UHT) has developed a process ? GRANSHOT® ? for quicksolidification of metals in water baths. In the process liquid metal is splintered ? granulated ?into small drops. The drops are rapidly cooled in a water bath where all the heat energy from theliquid metal is transferred into the water.

Kläder i hampa - ett miljövänligt alternativ/komplement till bomull?

Hemp has been used for textiles for a long time in history until it became illegal to grow in many countries in the 1930s. It is interesting from an environmental point of view because it doesn?t need any pesticides and in most locations it doesn?t need any irrigation either, compared to cotton, which normally requires big amounts of both pesticides and water for irrigation. Hemp is a bast fiber, which means that the fibers are located on the bast of the stem (on the outer layer of the stem). Therefore they cannot be spun directly, they have to be removed from the stem first.


Energikartläggning av polishuset i Gävle : Åtgärdsförslag för ett minskat energibehov i fastigheten Gävle Söder 17:10

The objective of this work was to introduce measures to reduce energy and water demand at Gävle Söder 17:10. To succeed, this energy audit has been made. The work is based on collected statistics from the property owner Norrporten, measurements, literature review and through consultation with experts in the field. Two models, one for each building, have been created in the simulation program BV2 to estimate the potential of energy measures based on the collected information. The models in BV2 have been verified against the statistics of the energy consumption.With the help of calculations and simulations, seven cost-effective measures have been identified.

Bevattning av lagrat virke vid svensk skogsindustri : omfattning och miljökonsekvenser

Most of the saw and pulp industries have stored wood nearby their production, the main reason is to have a continuous wood flow to the production. Wet storage of wood is of great importance to keep the wood quality. Without water sprinkling the risk of drying outand decomposition through biological activity increases significantly and will result in a negative effect on future production and quality. One drawback of wet storage of wood is the leaching of chemical substances into the surrounding recipient. The log yard run-off contains phosphorus, nitrogen, phenols and organic substances. These substances can cause problems for the surrounding environment. The main objective of this project is to gain an understanding of the wet storage used by the Swedish wood industry and estimate the environmental consequences that run-off water will have on the recipient.

New public management från solidaritet till effektivitet

The public service within health and care has changed remarkably during the last 30 years. It has been inspired by management ideas from profit-making businesses. Those thoughts are an umbrella term called Nex public management. In what way has New public management influenced the public service in Sweden? Important concepts in the change of public service are quality, effektivity and goals.

Big Bath-Accounting- Sötrre engångskostnader vid VD-byten?

The purpose of this essay is to investigate if the companies listed on Nasdaq/OMX Stockholm Large Cap use the earnings management phenomenon Big Bath Accounting to a greater extent when a change of management (CEO) is made.Management tends to use earnings management when there is a bonus plan linked to the result of the company. To gain maximum bonus the management will try to manipulate the result in a way that in a long term maximize their utility. Through the earnings management technique Big Bath the management is given the possibility to take one large cost as a one-time expend, even though the cost is supposed to run over several financial years. This, of course, within the legal framework. A big bath may occur when there is an impairment of goodwill, tangible and/or intangible assets or larger provisions for future expense, or both of them at the same time..


Närsaltsdosering till luftad damm : en åtgärd för ökad TOC-reduktion hos Skoghalls Bruk luftade damm

In the process of making carton boards into Skoghall Mill, are great quantities of water being contaminated. This water has to be treated before it is possible to release into the recipient, Kattfjorden. One of the contaminations that is important to extract from the wastewater, is organic carbon (measured as TOC-total organic carbon) because microbiological breakdown can lead to the bottom becomig free of oxygen.The wastewater treatment at Skoghall Mill is done through an external wastewater treatment that is located at the factory. The biological treatment (aerated lagoon) is a 140 000 m3 water pool with surface aerator, which is give oxygen to the water. In the lagoon live microorganisms who performs the biggest part of the TOC-reduction.One problem with the lagoon is that the treatment of TOC is considerably worse during wintertime than during summertime.

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