Design of Gas Permeation Systems

Zolandz, Raymond R.; Fleming, G. K.

doi:10.1007/978-1-4615-3548-5_4

Cited by 34 publications

(5 citation statements)

References 32 publications

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“…The process is only viable up to a temperature of 220 K, after which the N 2 /He selectivity is too low to achieve the desired separation. The most important feature of this process is the removal of the major component nitrogen into the permeate stream, which is counter to most gas separation configurations . As such, there are significant throughputs associated with the recycle streams from the second and third membrane stages, to ensure high He recovery.…”

Section: Resultsmentioning

confidence: 99%

“…The most important feature of this process is the removal of the major component nitrogen into the permeate stream, which is counter to most gas separation configurations. 23 As such, there are significant throughputs associated with the recycle streams from the second and third membrane stages, to ensure high He recovery. The He composition in the retentate stream from the first and second membrane stages is provided in Figure 9.…”

Section: Industrial and Engineering Chemistry Researchmentioning

confidence: 99%

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Helium Recovery through Inorganic Membranes Incorporated with a Nitrogen Rejection Unit

Scholes

2018

Ind. Eng. Chem. Res.

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Helium recovery and purification from a natural gas process is increasingly being investigated globally to address rising market demand, as traditional helium sources become depleted. Here, process simulations of two types of inorganic membranes were undertaken in Aspen HYSYS to investigate the possibility of recovering and purifying helium from the Nitrogen Rejection Unit (NRU) offgas close to the NRU’s operating temperature. The two membranes were a cobalt-silica membrane that has He/N2 selectivity through molecular sieving and a zeolite membrane that has N2/He selectivity at low temperatures, because of surface diffusion. Both membranes were able to achieve the desired He recovery and purification through a three-membrane-stage process, and for a feed of 4% He, the cobalt-silica membrane could achieve the same separation performance through a two-membrane-stage process above 340 K, because of increasing selectivity with temperature. In contrast, the zeolite membrane could not operate above 220 K, because of the loss of the surface diffusion mechanism. The difference in permeance of the two membranes significantly affected the membrane area, with the cobalt-silica membrane requiring three orders of magnitude more area than the zeolite membrane to recover and purify the same amount of helium. However, the zeolite membrane’s selectivity for N2 meant that the vast majority of the NRU offgas passed through the membrane into the permeate streams. Hence, to ensure a high helium recovery, the permeate streams from the second and third membrane stages must be recycled, resulting in permeate gas throughputs that are orders of magnitude higher than the cobalt-silica membrane process. This placed significant recompression duty on the zeolite membrane process, compared to the cobalt-silica process, and, as such, the zeolite membrane’s power duty for helium separation was at least five times greater than that of the cobalt-silica membrane. Hence, there is a tradeoff between the two inorganic membranes for helium recovery and purification, based on required membrane area and power demand.

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Section: Resultsmentioning

confidence: 99%

Section: Industrial and Engineering Chemistry Researchmentioning

confidence: 99%

Helium Recovery through Inorganic Membranes Incorporated with a Nitrogen Rejection Unit

Scholes

2018

Ind. Eng. Chem. Res.

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“…The membrane permeability and selectivity are essential metrics in assessing the performance of the fabricated NPDMS membranes for gas separation. The permeability of gas i ( P i ) in the barrer was computed using Equation , where Δp is the pressure difference, J i is the steady‐state gas flux, and L is the membrane thickness 29 . The permeability‐selectivity correlation is described by Equation , where k is the upper bound front factor, α is the separation factor ( P i /P j ), P j is the permeability of the less permeable gas, and n refers to the slope of the logarithm–logarithm limit.…”

Section: Methodsmentioning

confidence: 99%

“…The permeability of gas i (P i ) in the barrer was computed using Equation 1, where Δp is the pressure difference, J i is the steady-state gas flux, and L is the membrane thickness. 29 The permeability-selectivity correlation is described by Equation 2, where k is the upper bound front factor, α is the separation factor (P i /P j ), P j is the permeability of the less permeable gas, and n refers to the slope of the logarithmlogarithm limit. A logarithmic plot of the separation factor versus the permeability of the more permeable gas, resulting in the Robeson upper bound, was obtained.…”

Section: Samplementioning

confidence: 99%

PDMS‐silica composite gas separation membranes by direct ink writing

Gutierrez

Caldona

Yang

et al. 2023

J of Applied Polymer Sci

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Polydimethylsiloxane (PDMS)‐based membranes containing amine‐functionalized and unfunctionalized silica particles were fabricated via direct ink writing for CO2/N2 gas separation. The printability of the inks was evaluated by rheological measurements, while spectroscopy, microscopy, thermal measurements, and mechanical testing were employed to characterize the printed membranes. The surface morphology of the membranes revealed the absence of voids, demonstrating their suitability for gas separation. The printed membranes also exhibited desirable thermal and mechanical properties (i.e., thermal degradation temperature of 518 °C and tensile strength as high as 1.178 MPa with 529% elongation). The PDMS‐based membranes generally displayed high permeability for CO2 but slightly low selectivity for the CO2/N2 gas pair. The best‐combined permeability‐selectivity performance of 8794 barrer and selectivity of 11.64 was demonstrated by the printed PDMS membrane containing no SiO2 fillers. The inclusion of unfunctionalized SiO2 particles generally increased the membrane's gas permeability but compromised the selectivity. In contrast, membranes with amine‐functionalized silica showed improved selectivity compared to membranes containing unfunctionalized silica. Overall, the performance and characteristics offered by the PDMS/silica composite membranes demonstrated the potential of 3D printing as an economical and sustainable fabrication approach to developing materials for carbon capture applications.

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“…The fluid package was Peng-Robinson, which is reliable over a wide range of temperatures and pressures, and has previously been applied to CO 2 capture [16,17]. The gas separation membrane process was based on an in-house programmed module, using standard mass transfer equations for cross-flow and counter-flow configurations [18].…”

Section: Methodsmentioning

confidence: 99%

Membrane-Cryogenic Post-Combustion Carbon Capture of Flue Gases from NGCC

Scholes

Wiley

2016

Technologies

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Membrane gas separation for carbon capture has traditionally been focused on high pressure applications, such as pre-combustion capture and natural gas sweetening. Recently a membrane-cryogenic combined process has been shown to be cost competitive for post-combustion capture from coal fired power stations. Here, the membrane-cryogenic combined process is investigated for application to post-combustion carbon capture from the flue gas of a Natural Gas Combined Cycle (NGCC) process. This process involves a three-membrane process, where the combustion air is used as the sweep gas on the second membrane stage to recycle CO 2 through the turbine. This ensures high CO 2 recovery and also increases the CO 2 partial pressure in the flue gas. The three-CO 2 -selective membrane process with liquefaction and O 2 -enrichment was found to have a cost of capture higher than the corresponding process for coal post-combustion capture. This was attributed to the large size and energy duty of the gas handling equipment, especially the feed blower, because of the high gas throughput in the system caused by significant CO 2 recycling. In addition, the economics were uncompetitive compared to a modelled solvent absorption processes for NGCC.

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Design of Gas Permeation Systems

Cited by 34 publications

References 32 publications

Helium Recovery through Inorganic Membranes Incorporated with a Nitrogen Rejection Unit

Helium Recovery through Inorganic Membranes Incorporated with a Nitrogen Rejection Unit

PDMS‐silica composite gas separation membranes by direct ink writing

Membrane-Cryogenic Post-Combustion Carbon Capture of Flue Gases from NGCC

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