Continuous Casting of Asymmetric Tubular Reverse Osmosis Membranes

  • John L. Richardson
  • Gilbert Segovia
  • Wilfred H. Bachle
  • H. Andre Parker-Jones


The advantages of tubular reverse osmosis module configurations for desalination primarily result from the large (typically 0.2 to 1 inch in diameter) characteristic fluid flow cross section and its uniformity in the flow direction. These inherent characteristics of the tubular module yield, with proper design, advantages of minimal fouling tendency, higher fractional recovery operation, and ease of physical in situ cleaning of the membrane surface in comparison with the performance of module geometries characterized by much smaller fluid flow cross sections and flow paths that are both exceedingly tortuous and contain many flow regions of stagnation and relative quiescence. From a cost-to-manufacture standpoint, full exploitation of the tubular module’s operational advantages will accrue as the cost for casting uniform, high performance tubular membrane is reduced to a level as close to the cost of polymer itself as is possible. Since, in the case of cellulose acetate, approximately 1/64 pound of polymer is required to produce one square foot of membrane 8 mils thick[1], then the cost of polymer is slightly greater than 1 cent per square foot of membrane or less than 1/10 of a cent per gallon/day of permeate flow capacity. The differential between this base cost, to which must be added the comparable cost of the other casting solution ingredients, and the cost of tubular membranes cast in the usual batch manner[2] is significant.


Shear Rate Cellulose Acetate Continuous Casting Casting Solution Continuous Casting Process 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    S. Manjikian, S. Loeb, and J. W. McCutchan, “Improvement in Fabrication Techniques for Reverse Osmosis Desalination Membranes.” Proceedings of the First International Symposium on Water Desalination, Vol. 2, Washington, D. C.: U. S. Dept. of the Interior, Office of Saline Water (1967). pp. 159-173.Google Scholar
  2. 2.
    S. Loeb, Desalination, 1, 35 (1966).CrossRefGoogle Scholar
  3. 3.
    B. Kunst and S. Sourirajan, J. Appl. Poly. Sci., 14, 723 (1970).CrossRefGoogle Scholar
  4. 4.
    J. S. Johnson, J. W. McCutchan, and D. N. Bennion, “Preparation and Performance of Cellulose Acetate Semipermeable Membranes for Sea Water Service.” Report UCLA-ENG-7139, University of California at Los Angeles (June 1971).Google Scholar
  5. 5.
    John L. Richardson, Gilbert Segovia, et al., “Reverse Osmosis Tubular Module Optimization.” OSW Research and Development Progress Report No. 455 (December 1969).Google Scholar
  6. 6.
    John L. Richardson, G. Segovia, and Alexander O. Brodie, “Development of an Improved Tubular Reverse Osmosis Module for Water Treatment.” OSW Research and Development Progress Report No. 576 (December 1970).Google Scholar
  7. 7.
    U. Merten (Ed.), Desalination by Reverse Osmosis, The M.I.T. Press, Cambridge, Mass. (1966).Google Scholar
  8. 8.
    R. B. Bird, W. E. Stewart, and E. N. Lightfoot, Transport Phenomena, John Wiley & Sons, Inc., New York, (1960), pp. 98–101, 119.Google Scholar
  9. 9.
    R. B. Bird, “Macromolecular Hydrodynamics.” Chapter 1 in Lectures in Transport Phenomena, No. 4 in the AIChE Continuing Education Series. American Institute of Chemical Engineers, New York (1969).Google Scholar
  10. 10.
    Ulv Lohmander, Die Makromolekulare Chemie, 72, 159 (1964). Note also references 2 and 3 of this article.Google Scholar
  11. 11.
    Peter J. Wolfe, “Nonlinear Least Squares Curve Fit (GAUSHAUS).” UWCC ID Code C0017–00/S0017–00. University of Wisconsin Computing Center, Madison, Wisconsin (1965).Google Scholar
  12. 12.
    A. G. Frederickson and R. B. Bird, Ind. Eng. Chem. 50, 347 (1958).CrossRefGoogle Scholar
  13. 13.
    Ernest C. Bernhardt (Ed.), Processing of Thermoplastic Mate-rials. Reinhold Publishing Corp., New York (1959).Google Scholar
  14. 14.
    John L. Richardson, G. Segovia, J. W. Mason, W. J. Subcasky, et al. ’’Advanced Reverse Osmosis Membrane-Module Systems.“ OSW Research and Development Progress Report No. 661 (July 1971).Google Scholar

Copyright information

© Plenum Press, New York 1972

Authors and Affiliations

  • John L. Richardson
    • 1
  • Gilbert Segovia
    • 1
  • Wilfred H. Bachle
    • 1
  • H. Andre Parker-Jones
    • 1
  1. 1.Liquid Process ProductsPhilco-Ford CorporationNewport BeachUSA

Personalised recommendations