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2333 Uppsatser om Biological wastewater treatment - Sida 4 av 156

Utvärdering av avloppsvattenreningen vid Hallsta Pappersbruk : Kartläggning av inkommande avloppsvatten och optimering av driftparametrar

Hallsta paper mill uses large amounts of water during the pulp and paper making processes. The wastewater is treated in two separate activated sludge processes referred to as BIO 1 and BIO 2. The main aim is to reduce the organic substance content, measured as COD (Chemical Oxygen Demand) before the wastewater is released into the environment. Since the effluent produced is very rich in organic substances, the addition of nitrogen (N) and phosphorus (P) are necessary to give satisfactory treatment results. Problems with sludge bulking sometimes occur which lead to increased levels of suspended matter and nutrients in the effluent.

Energieffektivisering i ett reningsverk för skogsindustriellt avloppsvatten genom förfällning av extraktivämnen

Pulp- and papermills expend vast amounts of water in order to produce pulp, paper and cardboard. Hence, they alsocreate vast amounts of waste water which has to be cleaned before it can be released into the receiving body of water. Insuch a wastewater treatment plant, tremendous amounts of energy are expended by the aeration in the biologicalcleaning process. This aeration is necessary to supply the microorganisms that shall decompose organic material withoxygen, which they need for their metabolism. The transfer of oxygen from the gas phase to the liquid phase isprimarily inhibited by surface-active substances in the waste water like resin acids or fatty acids.

Biologisk reducering av nitrat och nitrit i vatten

During the summer 2007 was a scrubber tested at Gruvön papper mill in Grums. The scrubber reduced NOx with 90 % in flue gas. NOx was transferred from the flue gas to a scrubber liquid as nitrate and nitrite. The scrubber liquid needs to be purified from nitrate and nitrite. One possible solution is to clean the scrubber liquid in Gruvön biologic cleaning construction.Microorganisms in the biologic cleaning construction need to assimilate nitrogen. There are environments free from oxygen in the cleaning construction.

Man har henne bara till låns : Adoptivföräldrars förhållningssätt till föräldraskapet och sina barns biologiska ursprung

The aim of this study was to examine how adoptive parents related to parenting and how they related to their children?s biological origin. Issues that were used were how adoptive parents described their own parenting, how they described their own thoughts about their children eventually wanting to search their biological origin and how adoptive parents described the child´s country of birth attitudes towards adoptees wishes to search their biological origin. The method used was qualitative research interviews. The theory that was used for analyzing the collected data was attachment theory.

Jag trivs bäst när havet svallar, och måsarna ger skri : En textanalytisk studie av biologisk mångfald i läroböcker

Biological diversity is one out of four dimensions, characterizing the subject of Biology ac-cording to the school curriculum. As a concept, biological diversity had its break through at the UN environmental conference in Rio de Janeiro in 1992, where the convention about bio-logical diversity, named CBD, was signed. According to the convention, almost all the na-tions of the world have engaged themselves to preserve the national diversity of species, in-cluding the diversity of genetics and ecological systems.This thesis focuses the biological diversity from the perspective of school books. The aim is to find out how the biological diversity is presented in biology books for students aged 12-15 years.In 1994, the current Swedish secondary and high school curriculum called LPO-94 was pre-sented. The biology books used in this study were published between 1994 and 2007, all of them exist in many editions and are published by three different publishers.The conclusion of the study is that all the biology books that were examined have reached different levels of the development in the field of biological diversity..

Uthållig sanitet : en förstudie i staden Picota, Peru

The access to good sanitary facilities is an important factor that elevates the experienced living standard as it improves hygiene and reduces the transmission of deseases. The ratification of the millennium goals by 189 countries demonstrates that this is an important international issue. Together the countries have taken upon themselves that the proportion of the population that lacked access to sustainable safe drinking water and sanitary facilities in the year 2000 will have been reduced by half by the year 2015. In Peru, the construction of sewage pipe networks to transport the sewage out of the direct human environment is progressing. The safety and sustainability of these systems can be questioned, since in Peru the sewage seldom receive any treatment before being emitted to a recipient. This is taking place in Picota and sorrunding villages as well. In the last 25 years several systems implementing small-scale onsite treatment have been introduced throughout Latin America in an attempt to give more people access to sustainable and safe sanitary facilities, reducing water consumption and taking advantage of the agricultural values of the sewage fractions while protecting the environment from its negative impact. In this study three different sanitary systems and the effects of different population growths were compared.

Stump treatment with the root rot antagonist phlebiopsis gigantea : - sensitivity of P. gigantea spores to high pressure stress; - reduced water consumption for stump treatment

Stump treatment today requires large quantities of clean water mixed with the protective product Rotstop, to fully cover the stump surface. In order to reduce the water consumption without reducing the coverage of the stump surface, the pressure in the stump treatment device can be increased. Therefore, the Phlebiopsis gigantea (Fr.) Jül. suspension used as a biological control agent to prevent Heterobasidion annosum (Fr.) Bref. infection was pressure-tested.

Att vara familjehemmets biologiska barn

The purpose with this study is to find out the experience of growing up in a family where the biological parents, has taken the assignment as family child caregiver?s. We have taken the help from the following question formulations to immerse ourselves in the subject. How do the biological children experience their relationship to their parents? How do the biological children experience their relationship to the children who are placed in their home? How do the biological children experience their participation in the family home? How do the biological children experience the need for support from outside the family? We have used a qualitative research method and interviewed six respondents with help from a semi-structured interview guide to get the respondents unique experiences told.

Marte meo-metoden på behandlingshem : en kvalitativ studie utifrån föräldrars och behandlares perspektiv

This study aims to explore parents and treatment personnels experiences of the Marte meo methodat a family treatment home. Three retrospective interviews were made with parents whoexperienced Marte meo treatment, as well as four interviews with treatment personnel. The purposeof the Marte meo method is to develop the interaction between parent and child. Previous resultsfrom studies show that treatment with the Marte meo method could provide positive effects to theparent child relationship. The results in this study have been analyzed by using parts of attachmenttheory, the salutogenic perspective and the term intersubjectivity.

Optimering av indunstningsprocess

The wastewater treatment plant at GE Healthcare's facility in Uppsala deployed a three step vacuum evaporator in 2007. The purpose of this was to pre-treat wastewater containing amines. The purpose of this thesis was to optimize thisprocess by reducing the amount of concentrate without releasing more nitrogen tothe environment and to examine if density could be used as a measurement of whenthe process should be ended.To create a foundation for optimization six test cycles were conducted with samples taken from all three steps. Both concentrate and condensate were tested as well as the incoming solution. Furthermore, the thesis has been expanded with a benchmarking part examining two different evaporators.

Energieffektivisering av aerbo reningsprocess : Tillsats av biprodukter i skogsindustriellt avloppsvatten

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.

Integreringsanalys av robot och arbetsstation på ITT Water & Wastewater

ITT Water & Wastewater ställer höga krav på kostnadseffektiv produktion vilket är en starkt bidragande orsak till att företaget är världsledande på sin marknad. För att erhålla kostnadseffektiv produktion har kombinationen människa robot visat sig vara framgångsrik.Examensarbetets syfte var att ta fram underlag åt ITT Water & Wastewater för att ta beslut om frigörande av indirekt personal vid line 15:s isoleringsstation på Elmotorverkstaden. Syftets uppfyllande stöttades av de underbyggande syftena att försöka höja robotens utnyttjandegrad samt reducera isoleringsmaskinens omställningstid.Arbetet bygger på kvalitativa och kvantitativa data i form av mätningar, intervjuer och egna observationer. Med stöd av erhållen data lyftes fyra olika förslag fram. Förslagen understryktes bland annat av integrering av arbetsmoment, förhöjd automatiseringsgrad och outsourcing..

The efficiency of the newly launched predatory mite Amblydromalus limonicus : biological control of thrips in cucumber

In this study, the efficiency of a newly launched predatory mite, Amblydromalus limonicus, has been examined for its potential to use as a biological control agent in cucumber production. A. limonicus can be used for biological control of two thrips species, Frankliniella occidentalis and Thrips tabaci. Field trials were conducted in greenhouses of two conventional cucumber growers in Scania, the southern part of Sweden. The basic control agent used against thrips was the predatory mite Amblyseius swirskii. In selected areas, additional A.

Behandlingsvåtmarkers reningseffekt på aktiva läkemedelssubstanser under vinterförhållanden : En studie av fyra svenska våtmarker för avloppsrening

Pharmaceuticals that are found in marine ecosystems are a threatening environmental concern, which is known to harm both animal and plant life. One of the reasons for this problem is that the waste water treatment techniques are not optimized to clear waste water from its pharmaceuticals contain. In this master thesis four Swedish treatment wetlands were studied, and their ability to reduce numerous pharmaceuticals in waste water. The four treatment wetlands that were studied were those in Oxelösund, Trosa, Nynäshamn and Eskilstuna. Two ecotoxicological tests and chemical analysis were used.

Utvärdering av substrat för biogasproduktion

The purpose of this study was to evaluate the different substrates that enter the digestion on Sundet wastewater treatment plant for production of biogas.This work have done an analysis of data about the biogasproduction from January 2012 to feburari 2013, this showed that the food substrates has a greater gas production than internal sludge.Through laboratory test the VS, TS and COD values for all the substrates used in the biogas production could be determinded. But the COD-method was less optimal for analysis of fat and food, therefore it optimized the method for fat but due to time constraints, this could not be done on the food substrates..

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