Induction times induced in an RO system by antiscalants delaying. Induction time model, страница 10

Frequency factor, m!2 s!1

Constant relating J and J, m!2

CP           

Concentration polarization ratio, dimensionless

[Ca]          —

Concentration of Ca ion in the bulk of the solution, mol/L

[Ca]w              

Concentration of Ca ion prevailing on the membrane surface,

mol/L

J              

Nucleation rate, m!2 s!1

Jv                       

Permeate flux, L/m2 h

k              

Mass transfer coefficient, m/s

(KNSP)CaSO4 —

Solubility product of CaSO4, mol2/L2

Lp

Real permeability, L/m2 h bar

Sb

Supersaturation ratio in the bulk of the solution, dimensionless

Sw

Supersaturation ratio prevailing on the membrane surface, dimensionless defined by Eq. (6)

[SO4]

Concentration of SO4 ion in the bulk of the solution, mol/L

[SO4]w

Concentration of SO4 ion prevailing on the membrane surface, mol/L

T

Greek

Absolute temperature, °K

Number of ions of crystallizing salt molecules

N

Wetting angle parameter

F

Crystal surface energy, mJ/m2

Feff1

Effective crystal surface energy defined by Eq. (4), mJ/m2


Feff2

Effective crystal surface energy based on < = 1, mJ/m2

J

Induction time, s

Lm

Molecular volume of crystalline phase, m3/mol

Acknowledgments

This study was undertaken in the framework of the EC Joule Programme Project JOE3-CT970053 performed by Suez-Lyonnaise des Eaux, CPERI of the University of Thessaloniki, AGBAR of Barcelona, Mekorot-Water Company and the Grand Water Research Institute (GWRI) of the Technion–Israel Institute of Technology. Thanks are due to the GWRI and to Professor Malcolm Chaikin for their invaluable support in providing the infrastructure of the Rabin Desalination Laboratory. This work forms part of the research undertaken by A.D. in partial fulfillment of the requirements of a Ph.D. degree.

References

[1]  R. Semiat, D. Hasson and D. Bramson, Proc. Membrane Technology Conference, AWWA, New Orleans, 1997, pp. 1013–1027.

[2]  A. Drak, K. Glucina, M. Busch, D. Hasson, J.M. Laîné and R. Semiat, Desalination, 132 (2000) 233– 242.

[3]  D. Hasson, A. Drak and R. Semiat, Desalination, 139 (2001) 73–81.

[4]  J.W. Mullin, Crystallization, 3rd ed., ButterworthHeinemann, Oxford, 1997.

[5]  W.L. Marshal and R. Slusher, J. Phys. Chem., 70(12) (1966) 4015–4027.

[6]  W.L. Marshal and R. Slusher, J. Chem. Engineering Data, 13 (1968) 83–93.

[7]  Calculation of supersaturation of barium sulfate, strontium sulfate, and calcium sulfate di-hydrate

(gypsum) in brackish water, seawater and brines, ASTM D 4328-97.

[8]  J.A.M. Meijer and G.M. Van Rosmalen, Desalination, 51 (1984) 255–305.


[9]  I. Sutzkover, D. Hasson and R. Semiat, Desalination, 131 (2000) 117–127.

[10]  A. Hina, G. H. Nancollas and M. Grynpas, J. Crystal Growth, 223 (2001) 213–224.

[11]  O.D. Linnikov, Desalination, 122 (1999) 1–14.

[12]  P.G. Klepetsanis, E. Dalas and P.G. Koutsoukos,

Langmuir, 15 (1999) 1534–1540.

[13]  L.G. Vasina, A.V. Boglovsky, I.L. Koldajeva and N.V. Noev, Desalination, 105 (1996) 159–163.

[14]  S. He, J.E. Oddo and M.B. Tomson, J. Colloid Interface Sci., 162 (1994) 297–303.

[15]  P.G. Klepetsanis and P.G. Koutsoukos, J. Colloid Interface Sci., 143 (1991) 299–308.

[16]  D.M. Keller, R.E. Massey and O.E. Hileman, Jr., Can. J. Chem., 56 (1978) 831–838.

[17]  R. Semiat, D. Bramson and D. Hasson, Proc. International Membrane Science and Technology

Conference, Sydney, Australia, 1996, pp. 271–273.