2 research outputs found
Effect of flow pattern in superstructure-based optimisation of fixed-site carrier membrane gas separation during post-combustion CO2 capture
The authors would like to acknowledge the University of the Witwatersrand Research Office for support.Membrane-based gas separation continues to be an area of interest that is being explored for various
applications and efforts are being made to enable large-scale implementation and commercialisation. Works on
techno-economic studies in areas such as carbon capture, natural gas sweetening, and biogas upgrading has
been reported. Various simulation studies have reported the effect of the membrane flow pattern on permeate
recovery and purity. The simulation studies in this area have been limited to single-stage and two-stage
membrane processes, while many of these studies considered polymer membranes, facilitated transport has
barely been investigated. In addition, optimisation studies that compared different flow patterns in the membrane
module have been few. The facilitation of gas permeation decreases as pressure is increased due to carrier
saturation. However, an increased pressure increases the driving force, and a trade-off should be achieved.
The different membrane flow patterns also have inherent driving force potential. In this work, a superstructurebased
model that also embeds a fixed site carrier permeation membrane has been developed for CO2 capture
from a coal-fired power plant and three scenarios based on the different flow patterns, i.e., co-current, countercurrent
and crossflow, were analysed to determine the effect of the flow pattern in the membrane module. The
main objective of the optimisation was to minimise the cost of capture. The counter-current flow pattern resulted
in the lowest cost of capture as it resulted in the most energy-efficient process system. The co-current flowbased
optimisation results in configuration result in an 18 % increase in cost compared to the counter-current
flow pattern optimisation run due to a 29 % increase in energy consumption. The crossflow pattern optimisation
results in a 9 % increase in the annualised cost of capture compared to the counter-current flow.http://www.aidic.it/cetam2023Chemical Engineerin
Efficient computation of solution space and conflicts detection for linear systems
Mémoire M1 sous la forme d'articleWe analyze a system of linear inequations , used for the purpose of Material Flow Analysis, with three different but complementary goals: (i) given some known variables , efficiently compute the solution space of unknown variables, (ii) if the set of constraints is infeasible, efficiently identify the conflicts, (iii) efficiently classify variables to determine whereas they are redundant, just measured, determinable or non-determinable. In each case we compare the efficiency of different algorithms or languages