Patent GB-592588-A (GB)
Title: Method of and apparatus for dialyzing solutions
IPC: G01N33/487
Filed: 1944-07-04
Abstract: <PICT:0592588/III/1> A dialyzing apparatus comprises, in combination, a chamber, one or more tubular membranes disposed therein, means for continuously circulating the solution to be dialyzed into contact with one surface of the tube or tubes, means for passing another liquid into contact with the other surface of the tube or tubes, and means for concentrating at least one of the liquids.  The apparatus comprises a vertical outer closed chamber 10 which is provided with a drain 13 having a valve 14.  Inside the chamber adjacent the ends are positioned headers 15 and 16, each provided with a plurality of holes into which are threaded short sections of pipe to which dialyzing tubes 18 are secured by any suitable means.  In one way, the short pipe has a threaded union joint and is sealed at its lower end by a tubular sleeve made of resilient material such as rubber, cork or sponge, forming a soft cushion over which the end of the dialyzing tube is slipped and secured by cords.  If desired, the outer surface of the sleeve may be grooved to provide seats for the cords.  An alternative means consists in pulling the tubular membrane through the short pipe; turning over the end to form a cuff and securing by means of a band.  These means may be used for securing the membranes to both upper and lower headers.  The tubes 18 may be disposed and arranged within the chamber 10 in any desired manner, provided that their external longitudinal surfaces do not contact one another.  The dialyzate (i.e., the liquid to be dialyzed) is supplied from a reservoir through a pipe 25 into an evaporator 27 where the liquid may be heated to 30 DEG -100 DEG C., preferably above 70 DEG C. and/or suction may be applied through pump 70 to draw off water, alcohol and other volatile substances, from the dialyzate.  From the evaporator, the dialyzate is pumped through a heater 28 into the chamber 10 via inlet 31, filling the lower section 32, tubes 18 and the upper section 33 until it overflows through the drain 34, which returns the excess liquid to the evaporator 27.  The lower section 32 is provided with an outlet pipe 35, fitted with a valve 74, which returns the dialyzate via extension joints 36 and 42 to the evaporator 27.  The other liquid is supplied from storage tanks 50 and 51 by means of pipes 52, 53 and 54, each of which is provided with a suitable valve.  The liquid is pumped upward through pipe 55, heated if desired by the heater 57 and delivered into the top of the chamber 10 where it flows downward, completely filling the space around the tubes 18.  The excess liquid is removed from the lower end through pipe 60 and is returned via the extension joints 361 and 421 to the reservoirs 50 and 51.  The dialyzing tubes and chamber 10 may be disposed in a horizontal plane, and the dialyzate may be caused to flow outside the tubular membranes.  The apparatus is adapted for dialyzing both organic and inorganic substances from organic or aqueous solutions. Organic substances may be separated from solutions by use of a semi-permeable hydrophobic tubing.  For dialysis of aqueous solutions, a hydrophillic tubing is employed.  Thus the apparatus may be used for separating inorganic or organic crystalloids from their solutions, or for separating crystalloids from colloids or for separating inorganic liquids from organic liquids, or for separating organic liquids from aqueous or non-aqueous solutions, and in particular for the separation of glycerine, butylene, glycol, and citric acid, sugar and inorganic salts from their aqueous solutions.  Specification 592,587 is referred to.