TY - JOUR
T1 - Conceptual process design and simulation of membrane systems for integrated natural gas dehydration and sweetening
AU - He, Xuezhong
AU - Kumakiri, Izumi
AU - Hillestad, Magne
N1 - Publisher Copyright:
© 2020 The Author(s)
PY - 2020/9/15
Y1 - 2020/9/15
N2 - Subsea natural gas processing attracts increased interest due to the smaller environmental footprint. Natural gas (NG) dehydration and sweetening are the main processing steps to avoid pipeline plugging and corrosion caused by the presence of water and CO2. Triethylene glycol (TEG) and amine absorption are the commercial technologies for these applications. However, membrane technology is considered as promising solutions for alternative subsea gas processing technologies, which provides unmanned operations without the requirements for rapidly periodical maintenance. In this work, a hybrid membrane process was designed for integrated dehydration and sweetening of a saturated natural gas containing 10 mol% CO2, and the process operating parameters such as inter-stage feed and permeate pressures are investigated. The simulation results indicated that the optimal permeate pressure in the 2nd -stage unit is 4 bar, and the optimal 3rd-stage feed and permeate pressures are15bar and 2 bar, respectively. The minimum specific cost of <2.71 × 10−3 $/m3 sweet natural gas was estimated to achieve the separation requirement of <2.5 mol% CO2 in purified NG together with captured high purity CO2 (>95 mol%) for enhanced gas recovery. However, due to the relatively low water selectivity of the dehydration membranes at high pressure of 60 bar used in the simulation, the hydrocarbon loss is still quite higher. Thus, advanced membranes with high H2O/CH4 selectivity at high pressure should be pursued to promote the application of the designed membrane system for subsea natural gas dehydration and sweetening.
AB - Subsea natural gas processing attracts increased interest due to the smaller environmental footprint. Natural gas (NG) dehydration and sweetening are the main processing steps to avoid pipeline plugging and corrosion caused by the presence of water and CO2. Triethylene glycol (TEG) and amine absorption are the commercial technologies for these applications. However, membrane technology is considered as promising solutions for alternative subsea gas processing technologies, which provides unmanned operations without the requirements for rapidly periodical maintenance. In this work, a hybrid membrane process was designed for integrated dehydration and sweetening of a saturated natural gas containing 10 mol% CO2, and the process operating parameters such as inter-stage feed and permeate pressures are investigated. The simulation results indicated that the optimal permeate pressure in the 2nd -stage unit is 4 bar, and the optimal 3rd-stage feed and permeate pressures are15bar and 2 bar, respectively. The minimum specific cost of <2.71 × 10−3 $/m3 sweet natural gas was estimated to achieve the separation requirement of <2.5 mol% CO2 in purified NG together with captured high purity CO2 (>95 mol%) for enhanced gas recovery. However, due to the relatively low water selectivity of the dehydration membranes at high pressure of 60 bar used in the simulation, the hydrocarbon loss is still quite higher. Thus, advanced membranes with high H2O/CH4 selectivity at high pressure should be pursued to promote the application of the designed membrane system for subsea natural gas dehydration and sweetening.
KW - Dehydration
KW - Membrane system
KW - Natural gas sweetening
KW - Process simulation
UR - http://www.scopus.com/inward/record.url?scp=85085099305&partnerID=8YFLogxK
U2 - 10.1016/j.seppur.2020.116993
DO - 10.1016/j.seppur.2020.116993
M3 - 文章
AN - SCOPUS:85085099305
SN - 1383-5866
VL - 247
JO - Separation and Purification Technology
JF - Separation and Purification Technology
M1 - 116993
ER -
