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97 Uppsatser om Chemicals - Sida 6 av 7
Användning av rötrest från kombinerad etanol och biogasproduktion : en jämförelse mellan tre alternativ
Scandinavian Biogas is involved in the planning of a combined ethanol and biogas factory in Karlskoga, Sweden. Besides biogas and ethanol large amounts of digester residues will be produced, about 450 000 liquid tonnes residue (~7,3 % Dry Substance( DS)). The objective of this thesis was to investigate possible uses of the residue from the biogas production process ScandgasEthanol developed by
Scandinavian Biogas, and to derive a methodological approach how to evaluate and compare handling systems. Three systems where proposed and compared in this thesis; spreading of the untreated residue as fertilizer (system 1), dewatering to a higher DS content to reduce transportation before spreading as fertilizer
(system 2) and production of a solid fuel by dewatering and drying the residue (system 3). The general conditions for the proposed systems were investigated in
terms of practical viability, economical aspects, environmental impact and energy inputs/outputs.
Optimering av den kemiska reningen vid Fläskebo deponi
Landfill leachate contains a variety of contaminants and is created when rainwater percolates the landfill. For landfill management the leachate is the main issue that can cause problems to the environment. At the landfill of Fläskebo, Renova AB treats the leachate in a local treatment plant. The treatment consists of a chemical treatment step with chemical precipitation, flocculation, sedimentation and filtration, and a final step with a carbon and peat filter. Renova has to ensure that the condition of the leachate reaches the regulation set for the landfill before it is released to the recipient.
Förslag till modell av kemikaliespridning i mark anpassad för användning vid räddningsinsats - Kemspill Mark 4.0
After emergencies involving chemical spills it is of great importance that correct measures are taken with short notice, both for the security of people and in order to minimize future environmental consequences. The RIB-unit at the Swedish Rescue Services Agency initiated this study, the aim of which is to propose changes to the existing chemical transport calculation tool: Chemical Spill 3.4, included in RIB - Integrated Decision Support for Civil Protection, so that it can be used for decision support as well as in preventive work. A rough estimation of chemical transport in the subsurface is considered being of great importance when making decisions during emergency response operations.The proposition presented in this report is a non site specific chemical transport model which is designed to give a rough estimation of NAPL flow in homogenous isotropic soil shortly after an instantaneous release. The model can be used at two levels; both in situations without access to information on subsurface properties, and with more accuracy in situations with knowledge of the included parameters. For that reason the user can choose among predefined alternatives or assign the parameters a numeric value to increase the quality of the model output.
Nursing technique and growth environment of Rabbit fish (Siganus guttatus) in the area of Tam Giang lagoon, Thua Thien Hue
SummaryIn the area to the east of Hue city, in Vietnam, lays Tam Giang lagoon, one of Asia's largest lagoons, with an area of 22,000 hectares. This lagoon is suitable for aquaculture. One reason for this is because the salinity differs from sweet to salty in different parts of the lagoon. The Vietnamese Government advocates an increase in environmentally-friendly aquaculture and the fish Siganus guttatus (Rabbit fish) is a candidate for this. This fish eats mainly algae and can be cultivated in a polyculture.
Mesatorrhalt
AbstractDegree thesis Solid content in Lime Mud By Andre Flodin Process operator program ? Umeå University 17/6 ? 2014 Pages: 21A thesis was made on Billerudkorsnäs production unit in Karlsborg where lime kiln in the causticising department of chemical recovery plant does not meet the required production. Causticising department is the final step in the chemical recycling unit. There, the filtered green liquor is mixed with lime to recover the cooking Chemicals used in the pulp factory. The cooking liquid is called white liquor.
Anaerob psykrofil behandling av hushållsavloppsvatten i UASB : Utvärdering av kapaciteten hos en två-stegs UASB-reaktor för behandling av hushållsavloppsvatten
Hammarby Sjöstad is a new district in southern Stockholm. A main objective with the Sjöstad project was to halve the environmental impact compared to other construction work. The environmental goals involve a halved water consumption rate, a local treatment of storm water and trials aiming to extract nutrients from the waste water. Sjöstadsverket is an experimental treatment plant used for testing new treatment processes for domestic waste water from Hammarby Sjöstad. The results are to be compared with the conventional process used at Henrikdals treatment plant today.
Utfackningsvägg av lättbetongblock i passivhus
AbstractThis report intends through a case study to investigate if lightweight concrete isappropriate as main material in the outer wall of a seven storey residential building.A technical design is carried out in accordance with the definitions and requirementsfor passive houses, given by FEBY?s1 ?Demand specification for passive houses?.A literature review is also carried out for a comparison between regular bolt wall andlight weight concrete wall, with a focus on the safety of moisture.The lightweight concrete block used in the report is as a celblock produced by thecompany H+H Sweden AB.The methods used have resulted in compliance with requirements andrecommendations from authorities. Calculations of energy, noise and moisture riskassessment has been carried out.The work has resulted in the conclusion that the lightweight concrete itself is notable to isolate in the extent necessary to obtain chosen U-value of 0,1 W/m2 ° C,without getting to thick. Therefore additional insulation is needed. There are fewrelevant reference objects built with only light weight concrete.
Miljö- och hälsorisker med konstgräsplaner
In Sweden today many municipalities and sport clubs chooses to build artificial turfs becauseof the increased period of using the turfs during the year and less maintenance requirementsthan for natural grass fields. What could be problematic with artificial turfs is the rubbergranules used as infill material in the turf matt. The rubber granules are often made fromrecycled tires, which may contain for the human health and the environment, harmful substances.This was the reason why the Swedish Chemicals Agency commissioned a statusreport in 2006 which, among other things, concluded that the environmental and health risksassociated with granules made from recycled tiers in artificial turf fields were small, but thatthere could be a local environmental hazard. The purpose and objective of the risk assessmentwas to identify how artificial turf plans granules can affect recipients in the area closeto the pitches and provide input to reduce the spread of metals and substances harmful forboth human health and the surrounding environment. The work was divided into three parts:(1) the construction of artificial turf pitches and their material content, the spread of granulatesoutside the fields and disposal of artificial turf pitches.
Upplevd trafiksäkerhet med mittbarriär
AbstractThis report intends through a case study to investigate if lightweight concrete isappropriate as main material in the outer wall of a seven storey residential building.A technical design is carried out in accordance with the definitions and requirementsfor passive houses, given by FEBY?s1 ?Demand specification for passive houses?.A literature review is also carried out for a comparison between regular bolt wall andlight weight concrete wall, with a focus on the safety of moisture.The lightweight concrete block used in the report is as a celblock produced by thecompany H+H Sweden AB.The methods used have resulted in compliance with requirements andrecommendations from authorities. Calculations of energy, noise and moisture riskassessment has been carried out.The work has resulted in the conclusion that the lightweight concrete itself is notable to isolate in the extent necessary to obtain chosen U-value of 0,1 W/m2 ° C,without getting to thick. Therefore additional insulation is needed. There are fewrelevant reference objects built with only light weight concrete.
Ekologisk bomull - Ett steg till ett grönare företag
Allt fler konsumenter väljer att göra ekologiska val, detta på grund av en ökad medvetenhet samt ett intresse för miljön. Bomull är en av de fibrer som används mest i kläder, trots detta så är bomullsproduktionen väldigt påfrestande för miljön. Mycket giftiga kemikalier, konstgödsel samt stora mängder vatten används vid dessa odlingar. Då bomullsodlingar är så pass resurskrävande måste alla klädföretag visa sitt engagemang i denna fråga. Detta kan göras på olika sätt, att välja ekologisk bomull framför konventionell bomull är då ett steg i riktning då den ekologiska bomullen är helt befriad från kemikalier och andra farliga medel.Syftet är att denna rapport ska verka som ett underlag för klädföretag som i dagsläget inte använder sig av ekologisk bomull.
H2S i aluminiumhydroxidslam : Undersökning av uppkomst och åtgärder
Denna rapport är en del av examensarbetet i utbildningen Kemiteknik med inriktning mot miljökemi och bioteknik. Uppdraget har varit att dels utreda orsakerna bakom problematiken med att svavelväte uppstår vid neutralisering av sköljvatten hos Sapa Profiler AB samt vid lagring av slam på Eka Chemicals AB och att hitta förslag till åtgärder. Detta har främst gjorts genom experiment. Det som undersökts är om det är bakterier som orsakar problematiken i slammet, deras förmåga till anaerob och aerob tillväxt, möjlighet till nitratreduktion, hur vattenhalten påverkar deras förmåga att överleva i slammet, hur Enzym Clean påverkar dem, hur bakterierna reagerar på olika temperaturer, deras morfologi och gramegenskaper samt hur deras kolonier ser ut. Vattenhalt, sulfathalt samt glukonathalt i slammet har också undersökts.
Strategival och suboptimering - Kopplingen mellan lågkostnadsstrategi och suboptimeringsproblematik
Bakgrund och problem: Företag strävar efter att synkronisera organisationens mål, strategioch styrning. Utifrån målen utarbetas en långsiktig strategi vilken ska genomsyrautvecklingen inom företaget. Den utformade strategin bryts ner och återfinns på en mängdnivåer inom organisationen. Då strategivalet påverkar en mängd processer inom företaget därnegativa sidoeffekter kan uppstå är det av intresse att utreda kopplingen mellan suboptimeringoch strategivalet.Syfte: Att utröna på vilket sätt en lågkostnadsstrategi leder till suboptimering samt via enunderforskningsfråga se hur suboptimeringen påverkar de i fallstudien aktuella företagen.Metod: Studien är utförd på fyra stycken organisationer vilka får representera en större del aven generell verklighet. Med kostnadsledande strategi menas att ständigt sträva efterkostnadsrationalisering och effektivisering av processer i syfte att erbjuda marknaden lägstapris.
Second hand- och vintagekläder Vs. Nyproducerade kläder - En studie kring huruvida köp av andrahandskläder leder till lägre konsumtion av nyproducerade plagg.
I dagens Sverige konsumeras årligen stora mängder kläder. Nyproduktion av textil har en betydande miljöpåverkan med bland annat stor åtgång av vatten samt mängder av kemikalier. Ett alternativ till allt nyproducerat skulle kunna vara andrahandsmarknaden för kläder.Syftet med studien är att undersöka om de kvinnliga kunderna hos butikerna Myrorna och Beyond Retro konsumerar färre nyproducerade plagg för att de konsumerar second hand- och vintagekläder.Vi har använt oss utav en kvantitativ undersökning där vi intervjuat totalt hundra stycken respondenter i anslutning till Myrorna och Beyond Retros butiker. Vidare har vi genomfört fem stycken kvalitativa intervjuer med vana konsumenter hos ovannämnda butiker, för att fånga deras resonemang bakom svaren.De kvantitativa intervjuerna visar på att en liten majoritet anser sig konsumera färre nyproducerade plagg för att de konsumerar second hand- och vintagekläder. Samt att det överhängande motivet bakom köpen var att second hand- och vintagekläder är unikt och trendigt.
Markberedningens, planteringspunktens och behållardjupets inflytande på granminiplantors etablering i fält :
A new type of forest tree seedling, called mini seedling, has been developed by the University
of Dalarna in Garpenberg, Sweden. Compared to traditional containerized seedlings
that are grown for 1 ? 2 years, mini seedlings are grown for only 10 weeks. The mini seedlings
are small, easily planted, cost effective, and reduce the amount of Chemicals used in
the nursery. Research has shown that mini seedlings tend to have higher overall survival
rates than traditional container seedlings.
Avskiljning av uran från dricksvatten med reaktiva filter :
Water is our most important provision and its quality is above all dependent on the
geological conditions in the area from where it is extracted. Due to geological
properties there are certain areas with an elevated risk of high uranium levels in the
ground water, which in turn constitutes a risk for human health. Consumption of water
that contains a high concentration of uranium implies a health risk due to the chemical
characteristics of uranium. Livsmedelsverket (The National Food Administration) and
Socialstyrelsen (The National Board of Health and Welfare) therefore recommend that
precautionary measures should be taken when the uranium concentration in ground
water exceeds 15 micrograms per litre. In particular, drinking water collected from
wells in areas with uranium-rich bedrock may have a harmfully high level of uranium.
One of the wells of the Ärla water purification plant, located near Eskilstuna, Sweden,
contains water that exceeds the guideline of 15 micrograms per litre.
One interesting technique for removing uranium from drinking water is adsorption to
reactive filter materials.