Distillation lines that are commonly used to predict feasible product regions are examined, focusing on the theoretical investigation and on the experimental verification of different models. Distillation lines based on the equilibrium stage model, residue curves, fluctuation transport theory, and multicomponent diffusion theory are derived and compared with experiments. The comparison with experiments shows that the consideration of the diffusional interactions between the components may be of essential importance when the column is operated close to a distillation boundary.

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Evaluating and understanding the cognitive demands of natural activities has been difficult using neurocognitive approaches like mobile EEG. While taskunrelated stimuli are commonly added to a workplace simulation to estimate event-related cognitive processes, using eyeblink activity poses an alternative as it is inherent to human behavior. This study aimed to investigate the eye blink event-related EEG activity of fourteen subjects while working in a power-plant operator simulationactively operating (active condition) or observing (passive condition) a real-world steam engine. The changes in event-related potentials, event-related spectral perturbations, and functional connectivity under both conditions were analyzed. Our results indicated several cognitive changes in relation to task manipulation. Posterior N1 and P3 amplitudes revealed alterations associated with task complexity, with increased N1 and P3 amplitudes for the active condition, indicating greater cognitive effort than the passive condition. Increased frontal theta power and suppressed parietal alpha power were observed during the active condition reflecting high cognitive engagement. Additionally, higher theta connectivity was seen in frontoparieto-centro-temporo-occipital regions as task demands increased, showing increased communication between brain regions. All of these results suggest using eye blinkrelated EEG activity to acquire a comprehensive understanding of neuro-cognitive processing while working in realistic environments.

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In most large coal-fired power plants an absorption process with a limestone suspension is applied today. The flue gas proceeds upwards through a series of spray headers that introduce a uniform liquid flux of droplets of the limestone suspension. These droplets resist the gas flow and provide a large mass transfer surface area required for the SO 2 removal process. During the spray overlapping the collision of the droplets may lead to a coagulation or a separation process depending on certain collision parameters such as surface tension, impact velocity and collision geometry. A model for droplet collisions was developed and implemented in a two-phase flow simulation by Euler-Lagrange. The model is based on experimental investigations with overlapping sprays.With the emission of pollutants into the air increasing, it is necessary to control the amount of particles released into the air. An understanding of filtration phenomena is therefore required, particularly of the main mechanisms of particle capture through a filter.This work consists in determining the combined efficiency of particle capture through the filter when several mechanisms are acting in synergy. The mechanisms of Brownian diffusion and direct interception allow particles to be captured on the pore surface of the filter; the first one concerns the smallest particles, while the second concerns the largest. A theoretical study has been carried out in the intermediate cross-over regime near the most penetrating particle size. The effects of slip are also taken into account, leading to an increase of the theoretical efficiency compared with the case for which slip is neglected. A finite coefficient of adsorption at the wall of the pore has been introduced, which implies that the particle concentration at the wall is not necessarily equal to zero, as is usually assumed.Our theory, which is based on a cylindrical pore geometry, can be adapted to ceramic filters by modeling their granular porous structure by a simple cubic lattice. Convergent-divergent pores in this lattice are assimilated to a cylindrical pore whose length is determined by the conservation of the membrane hydraulic permeability.The adjustment of only two parameters, namely the effective number of pores, which takes into account the tortuosity of the granular structure, and the coefficient of adsorption, allows us to obtain good agreement between the theory and experiment.