Review of analytical and numerical modeling for pressure retarded osmosis membrane systems

Study of Forward Osmosis Process and its Effects on the Concentration of Salt Lake Brine

“…Meanwhile, there are three concentration polarization phenomena in the osmosis process of the AL-DS mode: the concentrative external concentration polarization (CECP) on the FS side, the concentrative internal concentration polarization (CICP) in the porous support layer, and the dilutive external concentration polarization (DECP) on the DS side. The relation between concentration polarization and concentration can be defined as follows. , C E C P = π f , s π f , b ≈ C f , s C f , b = exp ( − J w k f ) DECP = π d , m π d , b ≈ C d , m C d , b = exp ( − J w k d ) CICP = π f , i π f , s ≈ C f , i…”

“…where D is the diffusion coefficient, x is the distance measured from the surface of the active layer (AL), C ( x ) represents the concentration at position x , and y is the distance measured from the surface of the porous support layer (SL), as shown in Figure . According to the boundary conditions of DECP and CICP, C f,i and C d,m can be expressed by eqs and C normalf , normali = C normalf , normalb 0.25em exp ( J normalw S D ) + B J normalw ( C d , m − C f , i ) [ exp true( J w S D true) − 1 ] C normald , normalm = C normald , normalb 0.25em exp ( − J w k d ) − B J normalw false( C normald , normalm − C normalf , normali false) [ 1 − exp ( − J w k d ) ] …”

“…Meanwhile, there are three concentration polarization phenomena in the osmosis process of the AL-DS mode: the concentrative external concentration polarization (CECP) on the FS side, the concentrative internal concentration polarization (CICP) in the porous support layer, and the dilutive external concentration polarization (DECP) on the DS side. The relation between concentration polarization and concentration can be defined as follows. , where k represents the mass transfer coefficient, S and D represent the structural parameter ( S ) and diffusion coefficient ( D ), and π represents the osmotic pressure, which can be quantified by the Van’t Hoff factor, as shown in eq . This method is reliable for applications in low-concentration solutions.…”

“…The relation between concentration polarization and concentration can be defined as follows. 53,54 i k j j j j j y…”

“…According to the boundary conditions of DECP and CICP, C f,i and C d,m can be expressed by eqs 16 and 17. 54 i k j j j j y…”