Browsing by Author "Ilmanen, Paulus"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Modeling of thin film evaporator for ionic liquid recycling
    (2017-06-13) Ilmanen, Paulus
     Kemian tekniikan korkeakoulu | Master's thesis
    World demand for textiles is on the rise and there is a need for fiber source that does not require arable land. Ioncell-F is a novel method of producing fiber from pulp. It uses ionic liquid [DBNH][OAc] to dissolve cellulose. Ionic liquid is expensive so it has to be recycled to make the process economical. Ionic liquid is thermally unstable, therefore the recycling has to be done with moderate temperatures. One way to separate and recycle ionic liquid from water is thin film evaporation. The purpose of this study was to model the evaporation of water from water/[DBNH][OAc] mixture in an agitated thin film evaporator in flowsheet simulator Aspen Plus. Accurate modeling of the evaporator is needed to design and optimize the recycling process. The study also studied the applicability of multiple-effect evaporation. Various modeling approaches were studied to simulate the thin film evaporator and an Aspen Plus model was developed based on batch distillation theory. The performance of the model was compared to an earlier developed model based on flash drum model and experimental data. The batch model gave more accurate results than the often used flash model. The model did not include the hydrolysis product of the ionic liquid, implementation of which should be the focus in future works. A case study was conducted and the applicability of double-effect evaporation was tested with the model. A rapid boiling point elevation at low water concentrations made it harder to implement multiple-effect evaporation in recycling of the ionic liquid. It could be done with right pressure and temperature settings for most of the evaporation, with one additional evaporator to achieve desired water content. Multiple-effect evaporation proved useful in both achieving purer vapor and lowering the total required heating power.
  • Suolan erotus juomavedestä - kemian laitetekniikan näkökulma
    (2013-04-30) Ilmanen, Paulus
     Kemiantekniikan korkeakoulu | Bachelor's thesis