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349 Uppsatser om Chemical pulp - Sida 14 av 24

Behandling av lakvatten med kemiska oxidationsmedel för att delvis bryta ned oönskade organiska förening : en studie utförd vid Hovgårdens avfallsanläggning i Uppsala

A renewed application for environmental permit for the Hovgården landfill in Uppsala shall be submitted before December 2004, therefore the municipality of Uppsala needs improved knowledge of the contents, mostly organic compounds in the leachate and they also want to find a method to minimize the emissions of these compounds. The purpose of this study was to find a practical and economical method based on chemical oxidation using oxidants. The oxidants investigated are Fenton's reagent, hydrogen peroxide, Oxypro, potassium permanganate and potassium persulfate. The study was made on untreated leachate and leachate that has been treated in an aerated dam followed by sedimentation dams collected from the Hovgården landfill, and alson on sludge water from sludge storage cells. The effects of the five oxidants have been established by analysing the UV absorbance at the wavelengths 253,7 nm and 260,0 nm at different pH values. The UV absorbance was used to indicate the amount of aromatic hydrocarbons in the water. Also analyses of iron and manganese were done after the experiments with potassium permanganate, hydrogen peroxide and Fenton's reagent.

Energikartläggning av integrerat massa- och pappersbruk

Målet med detta examensarbete har varit att utföra en energikartläggning på Nymölla Bruk med utgångspunkt i företagets be?ntliga energiaspektregister. Syftet har varit att tydliggöra hur energianvändningen på Nymölla Bruk ser ut. Bakgrunden till detta arbete är företagets deltagande i programmet för energieffektivisering i energiintensiv industri (PFE).I examensarbetet har en energikartläggning på Nymölla Bruk för år 2010 utförts. Fallstudien delades in i två steg där första steget i studien var att kartlägga energi?ödena in och ut från bruket.Andra delen av studien innefattade att kartlägga de interna processerna och deras energi?öden.

Utveckling av HPLC-metoder för kvantifiering av nyckelkomponenter i en villkorad emulsion

Traditionally, rolling mills use emulsions based on a mixture of oil and water for lubrication. Since two years ago SAPA has been using (instead of oil) a synthetic lubricant so called conditional emulsion for hot-rolling of aluminum. This lubricant is water based and homogenous at ambient temperature, but switches to a two-phase system at heating above the cloud point.This project aims to validate and if necessary modify an existing HPLC method for quantifying two out of three key components (A, B and C) in the conditional emulsion. Attempts to develop a method to quantify the pH adjusting components, X and Y were also made. These two methods are required to optimize the lubricant.Due to the complexity of the components, it has been difficult to present a method for quantification, and HPLC with ELS detection was chosen after a long series of trials.

Avsättningar i pappersmaskiner : Utbildning och förslag till processförbättringar

Deposits can be formed in the paper machine due to sticky materials from wood and recycled paper. These deposits get stuck on process equipment and cause the product quality to deteriorate and the efficiency of the paper machine is reduced. The purpose of this thesis is to increase the understanding about deposits among machine operators, and to suggest methods that can be used to reduce the amount of deposits formed in Bravikens paper machines.To fulfill the purpose of the thesis a pre-study, a literature review and interviews with machine operators and production staff, were carried out. These methods led to the planning and creation of an education about deposits for machine operators.The education about deposits for machine operators consisted of an interactive lecture to introduce the subject of deposits and a subsequent discussion. This approach was chosen to give the machine operators the opportunity to discuss their work situation on the paper machines related to their new knowledge about deposits.

Livet efter sfi : Vilka tankar har några sfi-elever om sin delaktighet i det nya landet och hur har de lyckats med att förverkliga uppsatta mål?

Boplatsvallar, often translated as semi-subterranean settlements, is an ancient monument with a diffuse definition. Defined as ?embankments that partially or completely surround a often lowered/dug down surface- this category of ancient monuments is also made up of a former category which traditionally was interpreted as winter settlements from the late Stone age in Sweden. This view of the ancient monuments carried over, to a certain extent, to this new definition. Should this be the case, that this category of ancient monuments are remains of winter settlements,  used recurringly over an extended period of time, then they should exhibit similar signals in regards to the distribution of the anthropogenically altered soil chemical and soil physical properties at the sites.The area around Lillsjön, Anundsjö parish in Ångermanland, have four boplatsvallar located separately in the regional area.

Uppfyller BIM förväntningarna som arbetsmetod för broprojekt?

The purpose of this work is to design and construct a device able to measure the mechanical attrition of oxygen carrier particles. Those particles are used in chemical looping combustion and in the present situation there is a lack of knowledge in how the attrition process work and in which extension. To find already tested solutions trying to answering this problem a literature study wascarried out and the best solution found was the so called Grace-Davison Jet-Cup method. This method is supposed to emulate the attrition caused by a cyclone separator and its advantages are that it is possible to use small test amounts, 5-10 g, and a thirty minutes long test will be enough to acquire useable results. An device was designed based on the Jet-Cup method with some slight modifications.

Miljöcertifieringssystemet Miljöbyggnad : Inverkan på utformningen av ett kontor

The use and attention given to the certification system ?Miljöbyggnad? has increasedin recent years. The system is completely Swedish and was initiated in 2005 by theBygga-Bo-Dialogen. Miljöbyggnad aims to create a healthy indoor environment, reduceenergy consumption and discourage the use of hazardous chemical substances. Thegrades that can be obtained are Classified, Brons, Silver and finally Gold.The work has been to examine three different models and conclude how the designof the models affect the grades in the certification system Miljöbyggnad.

Eutanasi : en skonsam död

This work is about euthanasia and how to use it on horses, dogs and cats. A description for each animal is done, about when it is time, why, which methods can be used and who is allowed to use them, how and where it shall be done. The methods we have concentrated on are: - Chemical destruction and the most common drugs for euthanatize horses, dogs and cats. - Physical disruption of the brain activity by a captive bolt, only for horses. The captive bolt only makes the horse unconscious and must always be followed by cutting off the vena jugularis. Then the horse dies because of loss of blood. No matter which method used for euthanizing, the animal must be declared to be dead by the operator before other measures. The testing criteria for death: muscle relaxation and cyanosis, cessation of reflex activity and pupillary dilatation, cessation of respiratory activity and cessation of all cardiac activity.

Foderhäckar till hästar i lösdrift :

Knowledge about feed racks for feeding forages to horses is lacking. Racks for sheep and cows are sometimes used for horses. Feeding roughage on the ground, or feeding silage bales with the plastic and net still on, can bring on a lot of different problems. The opportunity to control the hygienic quality is small and feed losses can be high. The purpose of this experiment was to investigate how the eating behaviour and consumption of horses were influenced by feeding racks of different constructions. Feed losses and changes in chemical composition of the forage were also studied.

Reducering av produktionstryck i A-linan : Förflyttning av produkt

In the production of pulp, paper and cardboard, a large amount of water is used daily. The water has to be purified in the internal purifying plant before it reaches the receiving body of water. In the biological purifying stage at the Stora Enso Skoghall mill, an aerated basin is used where the microorganisms, using oxygen, oxidize the organic material to carbon dioxide. The air is pumped from the bottom of the basin and the oxygen can then be transported from the air bubbles to the water through diffusion. The problem with aeration of waste water from the forest industry is that wood residues, such as fatty acids, are making the transport of oxygen in water more difficult.

Aquaculture : animal welfare, the environment, and ethical implications

The aim of this review is to assess the ethical implications of aquaculture, regarding fish welfare and environmental aspects. The aquaculture industry has grown substantially the last decades, both as a result of the over-fishing of wild fish populations, and because of the increasing consumer demand for fish meat. As the industry is growing, a significant amount of research on the subject is being conducted, monitoring the effects of aquaculture on the environment and on animal welfare. The areas of concern when it comes to animal welfare have here been divided into four different stages: breeding period; growth period; capturing and handling; and slaughter. Besides these stages, this report includes a chapter on the current evidence of fish sentience, since this issue is still being debated among biologists.

The effect of new raw materials on pellet prices

As demand for renewable energy is increasing rapidly, the market for biomass pellets is expected to continue to grow in the near future. Most of the new raw materials that are discussed for pellet production have one thing in common; the production costs will increase compared to using traditional raw materials such as sawdust and planer shavings. The aim of this thesis is to investigate to what degree increased use of new raw materials for pellet production will affect the general pellet prices in Sweden and to survey what plans Swedish pellet producers have concerning new raw materials. To investigate the raw material situation of the Swedish pellet producers an industry survey was performed. Literature studies were also made on previous research in the subject field. Calculations of the production costs for pellets were done for the raw materials sawdust, wet sawmill chips and energy wood respectively. New raw materials are already used by the large-scale pellet producers in Sweden.

Vattenkemin i Fyrisån under snösmältningen

Chemical substances are spread diffusely and uncontrollably as a result of the increased consumption of goods. REVAQ is a certification system that works to reduce the flow of hazardous substances to Swedish treatment plants and to create a sustainable nutrient recycling. According to REVAQ, the yearly accumulating rate of metals should not exceed 0.2% in soil per year. Silver and bismuth are two metals that do not fulfill this requirement. The silver concentration in sludge decreased during the last decade, however the last few years, it has leveled off.

Sederingsrutinens påverkan på resultatet av höftledsröntgen : en pilotstudie

Hip dysplasia is a common, inherited malformation of the coxofemoral joint that eventually leads to osteoarthrosis. Several breeds of dogs are affected and the prevalence varies between different breeds. As part of the effort to reduce the prevalence of hip dysplasia and select dogs suitable for breeding, radiological screening is performed by at least 12 months of age. Before the radiological examination the dog has to be chemically restrained, sedated or anesthetized. The sedation protocol used differs between veterinary clinics. The impact of sedation method of the screening result for hip dysplasia has been studied.

Kloridutlakning från flygaska : möjligheten till en lokal hantering

In Sweden, there are limits to how much leachable substances waste must contain in order to be deposited as hazardous waste. Fly ash from waste incineration often end up over the limit, mainly due to the chloride content. Fly ash is therefore often deposited abroad. The purpose of this study was to investigate the possibility to handle fly ash locally. To clarify how the law is applied, environmental reports and permit documents from ten waste sites with permission to deposit fly ash were studied.

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