Sök:

Sökresultat:

1184 Uppsatser om Plant Simulation - Sida 65 av 79

Luftflödesstyrning på Käppalaverket ? utvärdering av konstanta styrsignaler

På Käppalaverket i Stockholm står luftningen av de biologiska bassängerna för omkring en femtedel av verkets totala elenergiförbrukning. I ett försök att minska energikostnaden utvärderades under hösten 2010 nya metoder för luftflödesreglering på verket. Grundtanken var att styra luftflödet efter medelvärdet på utgående ammoniumkoncentration under en längre tid, istället för som idag efter momentana värden.Ett vanligt sätt att styra luftflöden på reningsverk idag är att använda återkoppling från utgående ammoniumkoncentration, vilket syftar till att alltid hålla den utgående koncentrationen vid ett valt börvärde. Lagstiftade gränsvärden på ammonium avser dock normalt medelvärden över en längre tid, såsom kvartal eller år. Istället för att anpassa luftflödet efter den inkommande belastningen är det därför möjligt att hålla luftflödet relativt konstant medan istället den utgående koncentrationen tillåts variera.I denna studie visades en energibesparing kunna erhållas om luftflödets variation reduceras.

Färsk ved till Hallstaviks pappersbruk :

Hallstaviks papermill is an industry plant within Holmen Paper. Hallstavik is a mechanical mill and produce newspaper and journal paper. During year 2000, Hallstavik used approximate 1.200 m3f spruce, either as logs or chips from sawmills. Due to that the production is running continuously the mill also needs raw material at the same rate. At some periods the supply of raw material cannot keep up pace.

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.

Nutrient effects on microorganism communities in nutrient poor soils

Better, more efficient fertilizers with great productivity and economic returns are needed, but it is important today to find fertilizers that are also sustainable. It is also important to carefully monitor their impact on the environment, including potential side-effects. In this context, the microbial communities that carry out numerous essential functions contributing to a functional ecosystem are of particular interest. The present study is a complement to a pot experiment that investigated the potential of different waste products for use as fertilizers and how they affect the microbial community. In the pot experiment, the clearest treatment change in microorganism community function was found in the fully fertilized treatment used as a positive control. The question was whether this was indirect, i.e.

Verksamhetsanalys Jämförelse mellan IAEA och OKG AB inom E.ON-koncernen

The safety and safety work on OKG, Oskarshamns Kraftgrupp, is supervised by SKI, Swedish nuclear power inspectorate. The task of SKI is to inspect that the nuclear power plants of Sweden runs in a safe way. The proprietor of the permit who runs nuclear power plants has the responsibility to maintain the required safety to run a plant. SKI publishes a number of statue books that OKG has to meet to be able to run the plants. SKI recommends in SKIFS 2 004:1, that OKG work with the safety requirements of IAEA.

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.

- Industrial design engineering study of PCM power plant -

En studie av en mindre kraftstation har gjorts i samarbete med Exencotech som forskar inom energi-återvinning. Deras kraftstation behandlar återvinning av värme från uppvärmt vatten som annars inte hade använts utan ansetts som ren förlust.Den studie som genomförts har gjorts på ett 100kW system med en så stor möjlighet till modularitet som är möjligt för anpassning och flexibel installation. Studien har även innefattat en 5kW prototyp och en modulär version av 100kW systemet upp till 0,5MW. Applikationen har som krav att framför allt minska volymen och storleken på systemet. Studien innefattar även en ergonomisk och användarvänlig inriktning vilket har påverkat designen och konstruktionen hos systemet.För att finna lämpliga lösningar och koncept till projektet har flera konceptgenereringar gjorts, liksom utvärderingar av lösningar.

Modellering, identifikation och reglering av en quadcopter

SUMMARYInventory of raw materials holds an important role in companies within the manufacturingsector. The inventory works as a buffer that secure the supply of materials to the productionunit. The aim of the inventory is to ensure that the company is able to meet the customers?demands despite fluctuations and variations in the material flow. The size of the warehouseand the layout are physical limitations for the quantity of articles that can be stored.

Förstudie för en vindkraftpark på Malmölandet i Norrköping : En undersökning av förutsättningarna för en vindkraftpark på ett sen tidigare planerat område

This is a feasibility study that examines various aspects of building a wind farm on Malmön in Norrköping. The feasibility study deals with interests of conflict, park design, electrical connections, production calculation, financial calculations and operating- and timetable.The report is divided into two distinct parts. First a theoretical part, which deals with conflicting interests, park design and electrical connections. Second a part with simulations dealing with production calculations, and financial calculations.Opposing interests are mapped so that problem areas can be found, and help put focus on the right places at a future environmental impact assessment (EIA). There are a number of areas where planners have to assess on an EIA, this thesis point on the most important areas.

Uppföljning av plantering på nedlagd åkermark i Skåne 1991-1996 :

The study was performed for the Swedish Regional Forestry Board in Södra Götaland. The study examines broadleaf plantations on former farmland that were planted between 1991 and 1996 with subsidy payments for conversion of farmland into forest. In particular, the study reviews forests planted in 1991-92 and 1994-96. In the early 1990s, Swedish agriculture was deregulated and direct subsides to farmers ended. The Swedish state instead granted farmers financial support and offered incentives for conversion of farmland and investments in order to make their unproductive land productive. The state supported conversion of farmland to broadleaf forest, forest for energy biomass production, or establishment of wetlands on former farmland. The County Administrative Boards and Regional Forestry Boards together monitored the planting of broadleaf forests.

Effekter av bearbetningsdjup i plöjningsfri odling

In Sweden, reduced tillage usually means non-inversion tillage, where primary tillage is carried out using chisel ploughs or disc implements. Primary tillage method is mainly determined by the desired soil loosening and the handling of soil residues. The effect of tillage depth was studied in field experiments in Skåne, Väderstad, Uppsala, Örebro och Västerås in different crops; spring oilseed rape, spring wheat, winter wheat and spring barley.The experiments generally had a randomized block design with the treatments mouldboard ploughing, deep chisel ploughing and shallow chisel ploughing, in some cases also shallow discing and no-tillage. In the experiments the following parameters were determined: seedbed properties, saturated hydraulic conductivity, penetration resistance, number of emerged plants and crop yield (all parameters were not determined in all experiments. Root growth and draught requirement were determined in two separate studies. There were no significant differences between tillage depths in non-inversion tillage in seedbed properties, plant emergence or root development.

Simulering av kombinerade rundvirkestransporter och kartläggning av dess effekter på servicedimensioner

Genom den rådande utvecklingen inom svensk rundvirkeförsörjning, som går mot större och färre produktionsanläggningar, blir medeltransportavståndet allt längre. Detta ökar behovet av järnvägstransporter av virke och förändrar därmed de andelar som bil- och järnvägstransporter utgör av den totala virkesförsörjningen. Ytterligare påverkan på transportval åstadkoms av varierande järnvägsnät och industriplacering i förhållande till detta. Syftet med denna studie var att utveckla en simuleringsmodell för att kartlägga effekterna av systemkonfiguration och omvärldsfaktorer på leveransprecision, lagernivåer och ledtider i massavedsförsörjning. Metoden som användes var objektorienterad händelsestyrd simulering i kombination med linjärprogrammering. Styrningslogiken som användes baserades på systemstatus och tog beslut om allokering av transportresurser genom justerad schemaläggning av tåg, anpassningar i biltransporternas totala kapacitet samt omstyrning av flöden mellan industrier. Två system användes, baserade på järnvägens struktur för norra respektive södra Sverige.

Laserskärning i Sverige : ? tekniken, marknaden och hur de utvecklas

Laser for material processing possesses a number of advantages which mean that it has been and will be an important component for a wide range of industries' future development. Cutting materials processing is the dominant use of laser technology and has revolutionized the manufacturing industry. The aim of this thesis is to describe the principles of metal cutting by laser, how laser cutting is applied in practice and to identify how Swedish companies are using laser cutting. For the theoretical and technical description of laser cutting literature studies are the primary source of information. The empirical basis for the mapping of the Swedish industry for laser cutting is grounded on a survey; this includes Swedish companies that use laser cutting in their production.

Effektivisering av råvarulager för lagerhållning av ett bredare artikelsortiment

SUMMARYInventory of raw materials holds an important role in companies within the manufacturingsector. The inventory works as a buffer that secure the supply of materials to the productionunit. The aim of the inventory is to ensure that the company is able to meet the customers?demands despite fluctuations and variations in the material flow. The size of the warehouseand the layout are physical limitations for the quantity of articles that can be stored.

Trängselskatt En jämförelse av systemet i Göteborg och Stockholm

SUMMARYInventory of raw materials holds an important role in companies within the manufacturingsector. The inventory works as a buffer that secure the supply of materials to the productionunit. The aim of the inventory is to ensure that the company is able to meet the customers?demands despite fluctuations and variations in the material flow. The size of the warehouseand the layout are physical limitations for the quantity of articles that can be stored.

<- Föregående sida 65 Nästa sida ->