Fraunhofer Chalmers Research Centre for Industrial Mathematics
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Vem bygger de för egentligen? En kritisk analys av gentrifiering och stadsutveckling i Bergsjön
No full textProcess Integration and Techno-Economic Assessment of CO2 Capture Processes Based on Phase-Change Solvents
No full textCarbon Capture and Storage (CCS) has been suggested as a promising technology to combat climate change and eventually reach negative CO2 emissions. An existing carbon capture method is Post Combustion Carbon Capture (PCCC), which is a type of CCS where typically an aqueous solution of amines is used to absorb CO2 from the exhaust gases of an industrial plant. PCCC is currently under research in an EU funded project called ROLINCAP, which investigates new types of absorption technologies, in hope of decreasing the cost of carbon capture. One of these technologies is the so-called phase-change solvents, which can reach a multiple phase equilibrium in the presence of CO2, each phase with different content in terms of amine, CO2 and water. Because of this quality, phase-change solvents require less regeneration energy compared to 30 wt% Monoethanolamine (MEA), which is the conventional solvent for absorption-based PCCC.
In this thesis, PCCC using the 35 wt% phase-change solvent N-methylcyclohexylamine (MCA) is compared with using the conventional solvent 30 wt% MEA. The capture processes are theoretically implemented on a 400 MW natural gas combined cycle power plant located in Thessaloniki, Greece. Process integration between the power plant and capture plant was performed to reduce the overall process system energy consumption. The most cost-effective heat exchanger network design among many was chosen for each solvent for further evaluation. Finally, a techno-economic assessment was performed on the proposed capture plant designs, to estimate the capital and operational cost for each solvent process. This was performed with two different cost estimation methods: one factorial method, the other used at the engineering consultant company COWI which is an actor in the ROLINCAP project.
Results from this thesis show that MCA is the better choice of solvent. It demands about half the heat for solvent regeneration compared to MEA and this difference is reflected in the operational costs. The MCA plant also has smaller flows and equipment, which resulted in lower electricity cost for machinery but also lower capital costs. Altogether, this makes the cost of capturing one tonne of CO2 much lower for MCA than MEA: 18.7 e/tonne CO2 compared to 47.3 e/tonne CO2. Another conclusion is that the potential of heat recovery between the power plant and capture plant is low. The reason is mainly because this is a retrofitting project which limits the integration potential due to constraints.
These results should be used with care. The thesis is based on models and information received from other actors. Because of a misunderstanding and modelling irregularity, the capture plant models exclude 19% of the exhaust gas flow and use a different gas composition. Because of this, the capture plant dimensions are not representative for the natural gas power plant in question. However, the composition and flows are still reasonable, and could represent partial capture. Also, the modelled MEA absorption process operates at a higher pressure than MCA. Because of this, the exhaust gas needed to be pressurised which resulted in higher electricity consumption, which increased the operational cost drastically. The higher operating pressure was most likely not required, and the capture cost for the MEA process is therefore higher than it could be
Matematiska modeller av läkemedelsprojekt
No full textDrug development is today controlled by investing in projects or drugs that are believed
to provide a big return on investment. The entire process of finding a potential drug until
it is possibly sold on the market involves a variety of tests and controls resulting in huge
expenses. The vast majority of drug projects undergoing this process do not meet the
high demands set on new drugs and is therefore discontinued. This subsequently results
in a loss for the pharmaceutical company in that project. It is against this background
that Captario has developed a cloud-based tool, Captario SUM. In Captario SUM, an
user is able to construct a mathematical model over their pharmaceutical project and
simulate the outcome to obtain a forecast of profitability and other interesting aspects
of the project.
In this report we investigate the impact variations in the variables, of such a model,
have on the forecast that is obtained. We have chosen to focus only on the forecast of
net present value which is a measure of profitability. To our help, we use methods in the
field emph sensitivity analysis which have been implemented on a prototypical model
of a pharmaceutical project. A secondary goal during the project has been to try to
find suitable methods that Captario in the future will be able to integrate with the tool
and further offer their customers a sensitivity analysis on their models.
After this investigation we found various sensitivity analysis methods that are well
suitable for Captarios tool. All methods identified that the recruitment rate for one of
the larger studies was the variable that had the greatest impact for profitability. Furthermore,
this report can be seen as a first step in the analysis of drug development
models and it is discussed how one could proceed with a deeper analysis
Kundcentrerad produktionsutveckling av lyftvagn
No full textSyftet med detta arbetet är att på ett konkret sätt påvisa vikten av att följa en grundlig och strukturerad produktutvecklingsstrategi. Det vill säga vikten av att göra rätt från början och inte slösa på resurser för att nå ett så bra resultat som möjligt till kund. Quality Function Deployment (QFD) heter den metoden använts för att bevisa just detta. QFD konkretiseras i detta arbetet genom att appliceras efter en önskad kravbild för
framtagning av en lyftvagn. Först bryts problemet på ett metodiskt tillvägagångssätt ner, varpå detta sedan analyseras vidare och studeras mer noggrant genom bl.a. Kano metoden för att i större utsträckning förstå kundens behov. En mycket viktig del i QFD sker därefter när
dessa krav som till en början kan verka abstrakta och svåra att definiera översätts till fysiskt mätbara parametrar, s.k. tekniska krav. Tillsammans med kundkraven jämförs därefter de tekniska kraven korsvis med varandra för att tydligt kartlägga deras direkta beroende av varandra i matrisen House Of Quality (HOQ). Matrisen HOQ kan ses som kärnan i QFD och används sedan som hjälp till att ta fram en preliminär produktspecifikation varpå sedan konceptgenereringen kan ta avstamp från
God psykosocial arbetsmiljö inom byggproduktion - En modell för att beräkna bemanningsbehov
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