Back to results
US 4,787,982 AGranted
Membrane separation apparatus and method
OwnerRicardo F. Caro, Robert J. Salterinventors
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
OwnerRicardo F. Caro, Robert J. Salterinventors
Estimating the term…
Continuous flow membrane separation is accomplished by apparatus adaptable for osmosis, dialysis, and electrodialysis. For electrodialysis to separate from one another, in a single step, multiple differing molecular weight components of fluids, a series of adjoining flow chambers are all separated from one another by semipermeable membranes and at least one of the chambers is separated from each adjoining chamber by a membrane having a molecular weight cutoff different from that of the membrane separating it from the other chamber adjoining it. To insure that neither the crude to be processed nor the desired product comes into contact with an electrode which could be deleterious, there is provided a minimum of four flow chambers adjoining one another in sequence. Adapted for all three separation processes is an assembly of a tubular membrane encircled by a flexible reinforcing mesh fabric with pressure in the fluid within the membrane sufficient to bulge the membrane radially and outward into the interstices of the mesh fabric to eliminate dead spots in fluid flow along the exterior of the membrane and sufficient to stiffen and straighten the membrane tube into essentially the form of a right cylinder. For electrodialysis, one or more additional, similar, successively larger reinforced membrane assemblies, surround(s) the first assembly. A housing encloses the membrane(s) to form a cartridge. The membranes are spaced to avoid contact with electrodes used in electrodialysis.
In a membrane separation apparatus for use in osmosis, dialysis, and electrodialysis, an assembly comprising a tube of thin, flexible, semipermeable membrane and reinforcing means, made of supple, soft material and provided with interstices, encircling said membrane tube to restrain said membrane tube against rupture when said membrane tube is inflated by internal fluid pressure to establish a transmembrane pressure difference sufficient to bulge said membrane generally radially outward into the interstices of said reinforcing means to a distance equal to at least the radial thickness of the elements of said material bounding the interstices and to generally straighten said membrane tube essentially into the form of a right cylinder and to stiffen it, the size of said interstices being such that said membrane bulges to said aforementioned distance when the magnitude of said transmembrane pressure difference is substantially less than the minimum at which any significant ultrafiltration occurs with said membrane.
In a membrane separation apparatus for use in osmosis, dialysis, and electrodialysis, an assembly comprising a tube of thin, flexible, semipermeable membrane and reinforcing means made of supple, soft material and provided with interstices, encircling said membrane tube to restrain said membrane tube against rupture, said membrane tube being expanded by internal fluid pressure to establish a transmembrane pressure difference sufficient to bulge said membrane generally radially outward into the interstices of said reinforcing means to a distance equal to at least the radial thickness of the elements of said material bounding the interstices, said membrane tube being generally fully inflated, straightened and stiffened by said pressure difference to assume essentially the form of a right cylinder, and the size of said interstices being such that said transmembrane pressure difference which produces the bulging of said membrane to said distance is substantially less than the minimum at which any significant ultrafiltration occurs with said membrane.
In a method for effecting membrane separation using an apparatus for osmosis, dialysis, and electrodialysis including a tube of thin, flexible, semipermeable membrane and reinforcing means, made of soft, supple material and provided with interstices, encircling said membrane tube to restrain said membrane tube against rupture,
Membrane separation apparatus for separating from one another components of different molecular weights carried by fluids, said apparatus comprising a series of sequentially adjoining chambers, through each of which fluid can flow, each chamber being separated from each adjoining chamber by a semipermeable membrane,
Dependencies are inferred from the claim text.