title: Recycling of coal seam gas-associated water using vacuum membrane distillation.
abstract: Coal seam gas-associated water (CSGAW), which is a by-product of coal seam gas (CSG) production typically contains significant amounts of salts and has potential environmental issues. In this study, we optimized a bench-scale vacuum membrane distillation (VMD) process with flat-sheet hydrophobic polytetrafluoroethylene (PTFE) membranes for the treatment of synthetic CSGAW (conductivity = 15 mS/cm). To study performance of the VMD process, we explored the effects of feed temperature (T(f) = 60, 70, and 80°C), feed flow rate (V(f) = 60, 120, and 240 mL/min), and vacuum pressure (P(v) = 3, 6, and 9 kPa) on water permeability through the PTFE membrane in the VMD process. Under the optimum conditions (i.e. T(f) = 80°C, V(f) = 240 mL/min, P(v) = 3 kPa), water permeability and rejection efficiency of salts by the VMD process were found to be 5.5 L/m(2)/h (LMH) and 99.9%, respectively, after 2 h filtration. However, after 8 h operation, the water permeability decreased by 70% compared with the initial flux due to the formation of fouling layer of calcium, chloride, sodium, magnesium, and potassium on the membrane surface.
authors.affiliation: School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW 2006, Australia.
authors.forename: Farideh
authors.initials: F
authors.lastname: Heidarpour
authors.affiliation: School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW 2006, Australia.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Shi
authors.affiliation: Department of Biomedical, Chemical and Environmental Engineering, 701 Engineering Research Center, University of Cincinnati, Cincinnati, OH 45221-0012, USA E-mail: chaesg@ucmail.uc.edu.
authors.forename: So-Ryong
authors.initials: SR
authors.lastname: Chae
mesh_terms: D003031:Coal; D057168:Distillation / Q000379:methods*; D005374:Filtration / Q000295:instrumentation / Q000379:methods*; D008567:Membranes, Artificial; D008855:Microscopy, Electron, Scanning; D010539:Permeability; D011138:Polytetrafluoroethylene; D011312:Pressure; D059027:Recycling; D012492:Salts / Q000737:chemistry; D014618:Vacuum; D014867:Water / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
chemical_list: D003031:Coal; D008567:Membranes, Artificial; D012492:Salts; D014867:Water; D011138:Polytetrafluoroethylene