A membrane-making method for improving the surface smoothness of lining microfiltration membrane

Abstract

The invention relates to a membrane producing method capable of improving surface smoothness of a lined microfiltration membrane. The membrane producing method comprises the following specific steps: putting resin, a solvent and an additive into a stirring kettle according to a certain proportion, stirring and dissolving to form a membrane casting solution; defoaming the formed membrane casting solution, and enabling the membrane casting solution to pass through a spinning kettle and a filter and enter a spinneret plate; atomizing a supporting body by using an atomizing device, enabling the supporting body to enter the spinneret plate, and combining the supporting body and the membrane casting solution at an outlet of the spinneret plate so as to uniformly coat the surface of the supporting body with the membrane casting solution to form membrane filaments; primarily shaping the membrane filaments after passing through a gel bath, then passing through other gel tanks to further separate out DMAC in the membrane casting solution into a water solution, diffusing water into membrane pores, and finally winding and post-processing to form the finished membrane filaments, and storing the finished membrane filaments in a filament receiving machine. By the preparation process, through atomization of the supporting body, the cost of the supporting body can be reduced while the surface smoothness of the membrane is ensured; the membrane producing method is simple and controllable in preparation process; in the process of combining the membrane casting solution and the supporting body, an adjustable variant is increased, so that the breadth of a product is increased.

Description

technical field [0001] The invention relates to a film-making method for improving the surface smoothness of the lining microfiltration membrane, which is widely used in the field of water treatment. Background technique [0002] The lined microfiltration membrane refers to the lined reinforced hollow fiber membrane, which adds a bundle-like support to the traditional hollow fiber membrane to increase the strength of the membrane filament, and its tensile strength and compressive strength are much higher than ordinary hollow fiber membranes. Fiber membrane, the tensile force is greater than 50KG, and its support material is generally polyester material, the price is relatively cheap. At present, the most commonly used weaving form for the support body in the water treatment industry is high weaving or crochet. The microfiltration membrane with lining is simply Apply the separation layer evenly on the surface of the support. The combination of the two needs to maintain a cert...

AI Technical Summary

Problems solved by technology

[0004] As the market competition becomes more and more fierce, some membrane companies will reduce the production cost of the membrane, and the main cost of the lined membrane lies in the support body. The film liquid is prone to "bleeding" (the casting film liquid flows into or seeps into the support body in the incomplete gel state) problem during the smearing process, resulting in the surface of the formed film being not smooth and uneven, and after this occurs, it is necessary to Make some adjustments to the formula, but the effect is often not obvious, and when the formula is changed, the membrane performance will change, it is difficult to weigh

In order to achieve the same surface smoothness of the film, it is necessary to use a support with a higher mesh number or apply a thicker separation layer. Both methods will increase the production cost, and when the density of the support is less than a certain level, even by increasing the smear Thickness can not achieve the effect of smooth film surface

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