TH36418A - Selecting damaged fibers - Google Patents

Abstract

The method for selectively filling damaged hollow fibers of a membrane module bonded together with a group of undamaged fibers in a cellular and hollow tube arrangement consists of (i) securing the membrane module vertically and immersing the ends of such modules in the liquid filler; (ii) moving the liquid filler upwards into the damaged fibers to a height above the point of damage; (iii) allowing the filler to solidify minimally; and (iv) trimming the ends of the fiber bundles in such a way that the undamaged fibers are left open, while the damaged fibers remain filled.

Claims (10)

1. The method for selectively filling damaged hollow fibers in a membrane module bonded together with undamaged fibers in a hollow cell-tube arrangement consists of the following steps: (i) securing the membrane module vertically and immersing its ends in the liquid filler; (ii) moving the liquid filler upwards into the damaged fibers to a height above the point of damage; (iii) allowing the filler to solidify minimally; and (iv) trimming the ends of the fiber bundles in such a way that the undamaged fibers are left open while the damaged fibers remain filled. 2. The procedure for selectively filling the damaged hollow ends of a membrane module, as per claim 1, consists of the following steps: (i) Fill the hollow end of each fiber at one end of the fiber bundle; (ii) Empty both the cell and hollow ends of the membrane module; (iii) Fill both the cell and hollow ends with impermeable fluid; (iv) Secure the module vertically, isolating the hollow end of the module from the impermeable fluid supply, and immerse the opposite end of the module to the filled container; (v) Reduce the pressure on the cell side for a sufficient period of time to allow the filled fluid to be drawn into the hollow end of the damaged fiber through the vacuumed damaged area via the hollow end; (vi) Allow the filled fluid to solidify as little as possible; (vii) Cut the end of the fiber bundle in such a way that the hollow end of the undamaged fiber is open while the damaged fiber remains filled; (viii) If necessary, repeat the above steps with the opposite end of the module. 3. The procedure for selectively filling the damaged hollow ends of a membrane module, according to (formula), consists of the following steps: (i) Fill the hollow end of each fiber at one end of the fiber bundle; (ii) Empty both the cell and hollow ends of the membrane module; (iii) Fill the cell and hollow ends with impermeable fluid; (iv) Secure the module vertically, isolating the hollow end of the module from the impermeable fluid supply, and immerse the opposite end of the module to the container of the filler fluid; (v) Reduce the pressure on the cell side for a sufficient period of time to allow the filler fluid to be drawn into the hollow end of the damaged fibers through the vacuumed damaged area in the hollow end; (vi) If desired, allow the filler fluid to partially solidify; (vii) Fill the cell side with permeable fluid, which will permeate into the hollow end to expel the filler fluid from the undamaged fibers; (viii) If necessary, repeat the above steps with the other end of the module. 4. Any one of the methods under claims 1 through 3 shall be used to fill a damaged hollow fiber with an internal diameter of at least 10 microns for at least 0.1 minutes under a differential pressure (Dp) of at least 3 centimeters of water until a minimum penetration depth of 5 millimeters is achieved. 5. Any one of the methods described in claims 1 through 3 shall be used to fill damaged hollow fibers with an internal diameter of at least 10 microns for at least 1 minute under a differential pressure (Dp) of at least 3 centimeters of water until a maximum penetration depth of 5 millimeters is achieved. 6. The method under claim 1 involves the use of a low-viscosity filler to fill damaged hollow fibers with an internal diameter of at least 20 microns without requiring a prolonged pressure difference sufficient to achieve the desired penetration depth, ranging from 0.5 to 10 centimeters, largely due to carpiling force. 7. According to claim 1, the module is in contact with the impermeable substance for a sufficient period of time for filling of both the hollow and feed sides. The impermeable substance is then added to the bottom of the module and moves upward within the module by carpilarial forces, leading to the expulsion of the impermeable substance from the damaged fibers. The impermeable substance penetrates the damaged fibers more effectively than it does the undamaged, unfilled fibers. 8. Method under claim 7 where the impermeable substance is SF6. 9. Methods for selecting the filling of damaged hollow fibers of membrane modules that are fused together with groups of undamaged fibers in specific cellular and hollow tube arrangements as described and shown in the figures and by referring to examples and drawings. 10. A method under one of the preceding claims where the fixation and selective filling of damaged fibers are performed simultaneously. (10 claims, 3 pages, 10 figures)