Deep CO2 removal using high pressure membrane contactors with low liquid-to-gas ratio

Selective Sulfur Dioxide Absorption from Simulated Flue Gas Using Various Aqueous Alkali Solutions in a Polypropylene Hollow Fiber Membrane Contactor: Removal Efficiency and Use of Sulfur Dioxide

“…When DI water was used as an absorbent, as reported in the results for general SO 2 removal experiments, the removal rate rapidly decreased from the beginning of the experiment, and then showed a removal rate of 50% or less in less than 30 min [ 16 , 32 , 33 , 46 , 47 ]. The tendency for various types of absorbents in this study is not much different from those in the previous studies.…”

“…It is possible to easily control the desired shape using a variety of polymers. However, there are disadvantages: swelling, wetting, and chemical resistance are weak [ 16 , 37 ]. For this reason, many studies considering polymer materials have used hydrophobic materials or increased hydrophobicity through a surface modification to minimize the wetting phenomenon [ 38 , 39 ].…”

“…Membrane contactors are known to be efficient gas–liquid contact reactors that can significantly reduce the volume compared to conventional reactors because they can provide a large specific surface area (m 2 /m 3 ) [ 15 ]. Besides, the investment cost and operation cost are lower than that of FGD scrubbers, so it is energy-efficient, it is easy to increase capacity by adjusting the number of modules, and it has the advantage of having excellent mass transfer properties [ 16 ]. According to a U.S. GTI Company report, when replacing the conventional FGD system with a membrane contactor, the total cost is reduced to 35%, the operating cost is reduced to 40%, and the footprint requirement is reduced to 40% [ 17 ].…”

Optimization of MDEA-PZ Ratio and Concentration for CO2 Removal in Semi-Lean Membrane Contactor Process

“…However, there is a restriction of using higher mass proportion of PZ since both viscosity and crystallization affinity of PZ hampers its usability mostly at higher concentration [10]. This is more crucial for a membrane contactor where the mass transfer resistance in the liquid phase represents 69-93% of the total mass transfer resistance [12]. Hence, there is trade-off between increasing the absorbent concentration and minimizing the liquid mass transfer resistance.…”

“…His conclusion however focused on improving the performance through increasing liquid temperature, solvent concentration, fiber numbers and the liquid flow rate [5]. Chan et al [12] alternatively pointed out that most published works of membrane contactor used excessive amine flow in order to achieve better performance, but this leads to high liquid-to-gas ratio (L/G) which results in high energy requirement for pumping and regeneration process The objective of this paper is to determine the optimized solvent concentration and MDEA-to-PZ ratio for removal of CO 2 from 25 mol% to 6.5 mol%. The liquid flowrate in these experiments is limited in order to achieve low L/G ratio of 0.6 -1.0 liter of liquid per mol CO 2 absorbed.…”