TiO2 nanoparticles as back reflector in thin-film solar cells

In the field of thin film solar cells light management is an important mechanism to improve efficiency. Manipulating the reflectivity and distribution of scattering angles significantly contribute to absorbing light with relative long wavelengths. In this thesis the scattering effect of titaniumdioxide nanoparticles (0.2-0.3 micron) for the use...

Embedding equation oriented models of process unit operations in a sequential modular flowsheet simulator: Study with a gas separation membrane model

Within the Dow Chemical Company the strategy is to centre process flowsheet design activities around the simulation tool Aspen Plus (from Aspen Tech Inc.). However, the model library of Aspen Plus is limited in type and number of models of process unit operations. Equation oriented modelling tools, such as gPROMS (from Process Systems Enterprise...

Optimal Safe Start-up of a Glycolether Process

Althougln start-up and shutdown only account for a small percentage of the total operating time of an industrial chemical plant, still up to 4 6% of the accidents occur during the start-up or shutdown. Furthermore, a large part of the costs of a start-up account for the extra personnel that is needed on site. Therefore, it is logical to optimise...

Dynamic modeling for startup and shutdown of a coupled reactor and distillation column

Competing in a global market place forces chemical industry to be flexible and cost-effective in production. To optimize production the processes are modeled before they are built. Normally these models show the steady-state behavior. This, however, will be insufficient to show the flexibility of the process and guarantee safety and...

Kinetic parameter determination and commercial reactor optimisation

Methods for kinetic parameter determination and economic reactor optimisation had been developed for the following kinetic case: P + Q -> I or P+Q -> R + S. Kinetic parameter determination was applied for elucidating the kinetic behaviour of the reacting system and it involved two statistical techniques: parameter estimation and experimental...

Optimization of the reactor section of a catalytic ethyleneglycol plant

A reactor network design is being given for the catalytic manufacture of ethyleneglycol. This relatively new process has a potential for major cost savings above the common, industrially applied, hydration of ethyleneoxide at high temperatures. To generalize the design of the plant, the reactor section of the catalytic ethyleneglycol plant is...

Modeling and stochastic simulation of the reactions and absorption of NOx in water

This work discusses the absorption of NOX in an absorption column. This is of relevance to the production of nitric acid and the fertilizer industry. Non-reacted NOx, released with stack-gases, plays an important role in environmental pollution problems. NOX absorption characterizes itself as a very complex system that is difficult to describe...

A Fast Method for the Prediction of Breakthrough Curves of Non-Isothermal Fixed-Bed Reactors

A model and a computer program have been developed for the prediction of breakthrough curves of a non-isothermal adsorption column, packed with porous spherical particles. At time zero, a step change in the concentration of an adsorbable component is introduced to the flowing stream. Together with this concentration step, the temperature of the...