JPS62155858A - Hollow yarn module - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention provides a method for using a large number of hollow fibers having the function of transferring substances or energy from one region to another or exchanging them between these regions. The present invention relates to a hollow fiber assembly (hereinafter referred to as a hollow fiber module) in which the predetermined ends of the bundle are fixed in a liquid-tight or air-tight manner within a housing by means of a fixing member.

[Conventional technology]

In recent years, hollow fiber modules using hollow fibers that have the function of moving substances or energy from one region to another or exchanging them between these regions have been used as filters, artificial S-units, heat exchangers, etc. As a result, it is being actively used in fields such as medicine, filtration, separation, and exchange of liquids and gases.

A typical form of these hollow fiber modules is that a large number of straight hollow fibers are arranged in a straight line, each fixed in a housing by a fixing member made of resin, with both ends kept open. Examples include those having a structure, or those having a structure in which a large number of linear or U-shaped hollow fibers with only one end open are bundled and fixed by one fixing member while keeping the open end.

In such hollow fiber modules, in order to increase the utilization efficiency per module volume, modules that use thinner hollow fibers to increase the contact area between the hollow fiber and the fluid that contacts the outer wall of the hollow fiber are attracting attention. However, as the hollow fibers become thinner, not only is it difficult to uniformly disperse and fix them in the module, but also the hollow fibers themselves tend to deform even after fixing. It is easily deformed by various external forces caused by fluid flowing outside. As a result, the predetermined linear shape of the hollow fibers within the module is likely to be disturbed, resulting in problems such as poor dispersion of the hollow fibers within the module or uneven distribution of the hollow fibers, resulting in poor performance stability. etc., there are still problems. In particular, when the ratio of the volume of the filled hollow fibers to the volume of the hollow fiber filling portion in the module, that is, the filling rate, is low, this tendency becomes more pronounced.

On the other hand, in recent years, in the medical field and the like, it has been desired to realize a module that is small in size and has high performance, with a small pressure loss in the fluid flowing outside the hollow fiber.

It is known that lowering the filling rate of the hollow fibers is effective in reducing the pressure loss of the fluid flowing outside the hollow fibers.

However, when the filling rate of the hollow fibers is lowered, the contact area of the hollow fibers with the external fluid decreases, so it becomes necessary to obtain higher separation and exchange efficiency with the limited surface area of the hollow fibers.

However, in conventional modules in which hollow fibers are linearly arranged parallel to each other, for example, in addition to the problem of disordered arrangement and uneven distribution of the hollow fibers, there is also a problem of fluid inside and outside the hollow fibers. Since the flow is in the laminar flow region, the film resistance on the surface of the hollow fiber is large, and there is a theoretical limit to performance, making it impossible to obtain high performance at a low filling rate.

Under these circumstances, module development is progressing in order to overcome the above-mentioned difficulties, but at present there are still problems to be solved in terms of economy, reliability, etc.

On the other hand, for example, in conventional modules in which the filling rate is increased in order to obtain high throughput, the hollow fibers become densely packed inside the hollow fiber bundle arranged in the module.
Fluid was not sufficiently supplied to the inside of the hollow fiber bundle, and the entire hollow fiber could not be used effectively.

[Problem that the invention seeks to solve]

The inventors of the present invention have created a module with high performance and stable quality by controlling the flow state without being affected by the external fluid flow and by having a good distributed arrangement state within the module. As a result of research to find out, the present invention was completed.

An object of the present invention is to provide a hollow fiber module that can achieve high efficiency in the separation and exchange of energy and substances even with a low hollow fiber filling rate.

Another object of the present invention is to provide a hollow fiber module that can obtain good hollow fiber utilization efficiency even when the hollow fiber filling rate is high.

Another object of the present invention is to provide a hollow fiber module that is inexpensive, easy to manufacture, and has excellent performance stability.

[Means for solving problems]

The above objects can be achieved by the following invention.

That is, the present invention provides a hollow fiber module in which a large number of open ends of non-linear hollow fibers having a large number of curved parts are fixed in a housing by a fixing member while maintaining the open state. It is.

The hollow fiber module of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a schematic cross-sectional view showing an embodiment of a hollow fiber module in which both ends of the present invention are bundled and fixed.

The hollow fiber module of the present invention basically has a structure in which open ends 1a at both ends of a large number of hollow fibers 1 having a non-linear shape are fixed in a housing 3 by two fixing members 2.

The housing 3 can be made of any material as long as it can impart a predetermined mechanical strength to the hollow fiber module of the present invention, and examples of such materials include metals, resins, glass, ceramics, etc. be able to.

Furthermore, the fixing member 2 can be made of a resin such as polyurethane, epoxy, unsaturated polyester, silicone, or the like.

Note that the configuration of the housing 3 and the arrangement of the hollow fibers 1 and fixing members 2 within the housing 3 are determined as appropriate depending on the intended use and performance of the module. In this example,
A supply port 3a and a discharge port 3b for the fluid flowing outside the hollow fiber are provided at predetermined positions in the housing 3, and the fixing member 2
This forms a partition between a fluid flowing outside the hollow fiber and a fluid flowing inside the hollow fiber, and a reservoir 4 for fluid flowing out from the inside of the hollow fiber or supplied to the inside of the hollow fiber.

FIG. 2 is a schematic sectional view showing an example of an embodiment of a hollow fiber module in which one end of the present invention is bundled and fixed.

In the hollow fiber module of the present invention, a large number of hollow fibers 1 having a non-linear shape are arranged in a U-shape through a support member 6 so that the open ends 1a of the hollow fibers are gathered at one end.
It has a structure in which part a is fixed by a fixing member 2.

In addition to the regular spiral shape shown in FIG. 1, the non-linear shape of the hollow fiber in the present invention includes multiple curved shapes such as a disordered shape with rings, a repeating S-shape, etc. A non-linear shape having a section can be mentioned.

In order to obtain hollow fibers having such a shape, a desired non-linear shape may be appropriately imparted to the hollow fibers according to a conventional method in the manufacturing stage of the hollow fibers. For example, a regular helical shape can be imparted directly during the spinning step of the hollow fibers or by post-treatment by main twisting or false twisting.

The outer diameter of the hollow fibers used in the present invention is appropriately selected depending on the desired performance and application of the module, and when used in a module that achieves high efficiency with a low filling rate, the outer diameter is 100 to 100.
It is said to be about 2000 μs.

Materials for forming the hollow fibers used in the present invention include:
Any material that can be shaped into the above-mentioned non-linear shape may be used, such as polyethylene, polypropylene, poly3-methylbutene-1, poly4-methylpentene-1, polyvinylidene fluoride, polyacrylonitrile, polyethylene terephthalate, Organic polymers such as polycarbonate, polyoxymethylene, polysulfone, silicone, urethane, ethylene vinyl acetate copolymer, ethylene vinyl alcohol copolymer, or ethylene vinyl chloride copolymer, fully bendable materials such as aluminum, stainless steel, etc. These can be appropriately selected depending on the desired use of the module of the present invention.

As for the non-linear shape of the hollow fibers used in the present invention, those given a regular spiral shape by twisting are convenient from the viewpoint of productivity and the like.

In this case, if a material is used that is difficult to maintain a spiral shape after heating if each tree is heated individually, or if productivity is desired to be increased, the same effect can be obtained by heating several trees at the same time.

The preferred number of twists varies depending on the size of the module, the material and shape of the hollow fiber, but the outer diameter is 100 to 2000)
For the hollow fiber of a, the unit T/m indicates the number of twists per 1 m.
When expressed as , it is preferably in the range of lO to 200 T/m, and particularly preferably in the range of 20 to 100 T/m.

By forming a hollow fiber bundle using such non-linear hollow fibers, the flow of fluid inside and outside the hollow fibers is in a laminar flow region in the conventional linear arrangement, so that the boundary film on the surface of the hollow fibers is reduced. The resistance was large, which limited the performance in exchanging and separating substances and energy, whereas the laminar flow state of the fluid inside and outside the non-linear hollow fiber is disturbed, so the surface of the hollow fiber is The membrane resistance can be reduced, and the separation and exchange efficiency of hollow fibers can be increased.

Furthermore, if a hollow fiber bundle is formed using hollow fibers having such a non-linear shape, it is possible to obtain appropriate bulkiness in the hollow fiber bundle. The bulkiness of the hollow fiber bundle is preferably such that the diameter of the hollow fiber bundle before being filled into the housing is larger than the inner diameter of the housing. By compressing such a hollow fiber bundle to some extent and filling it into the housing, the hollow fibers are uniformly dispersed in the housing, and the repulsive force in the somewhat compressed state acts to reduce the external force on the hollow fibers. The result is a module with performance stability that allows the hollow fibers to maintain a suitable shape even during use.

Appropriate bulkiness of such a hollow fiber bundle can be obtained by using hollow fibers having a deviation from a linear shape to the extent that the desired bulkiness can be obtained. In other words, this bulkiness increases as the non-linear shape of the hollow fibers forming the hollow fiber bundle deviates from the original linear shape, and by adjusting the degree of this deviation, the bulkiness of the hollow fibers obtained can be increased. can be set to a desired degree.

The deviation from the linear shape of the non-linear hollow fibers used in the present invention varies depending on the material and number of hollow fibers when forming the hollow fiber bundle, the structure and size of the inside of the housing to be filled, etc. For example, the degree of deviation from the linear shape of a hollow fiber in a non-linear shape is the ratio of the length in the non-linear shape to the length when it is a straight line (*) (length in the non-linear shape / When expressed as a straight line length (xtoo), 100. It is good to set the IN to 150.0%, preferably about 100.5 to 105.0%. This ratio is, for example, the ratio of the distance between both ends of a non-linear hollow fiber when the hollow fiber is stretched into a straight line by applying some stress to the straight-line distance between both ends of the hollow fiber in the state shown in Figure 1. It can also be expressed as

The filling rate of the hollow fibers in the present invention is also appropriately selected depending on the desired performance and use of the module, but it is particularly effective when the filling rate is 15 to 35%. With such a filling rate, for example, when used in an external perfusion type blood processing device that flows blood outside the hollow fiber, the blood flow rate is 2.21/m2.
・The pressure drop can be kept below loo+nmHg even if the flow is carried out at min. Therefore, blood can be processed only by drop blood removal, which is useful.

As mentioned above, even when the filling rate is lowered to reduce the pressure loss of the fluid flowing inside the module, in the module of the present invention, due to the bulkiness due to the non-linear shape of the hollow fibers, the above-mentioned It is easy to obtain good dispersion of hollow fibers in the module, which has been difficult in the past, and
The non-linear shape of the hollow fibers can prevent certain flow paths, or channeling, from occurring within the module.

On the other hand, in modules with a high filling rate, the inside of the hollow fiber bundle was conventionally packed with hollow fibers and did not function adequately, but in the present invention, the inside of the hollow fiber bundle is formed by hollow fibers that have a non-linear shape. In the hollow fiber bundle, the hollow fibers are spaced at appropriate intervals, and the liquid easily flows into the hollow fibers, so that the utilization efficiency can be significantly improved.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 Polyethylene hollow fibers with an outer diameter of 473 mm and a wall thickness of 72 mm are twisted at a twist rate of 25 T/m for every 4 fibers, and the ratio of the length in a non-linear shape to the length in a straight line is , 100.8
A non-linear hollow fiber having a regular helical shape of % was obtained. 2,256 of these hollow fibers are packed into a polycarbonate cylindrical housing 1 having a diameter of 45 mm and a length of 160 mm as shown in FIG. We manufactured a number of heat exchangers that were focused and fixed using polyurethane adhesive. Note that the filling rate of the hollow fibers in this case was 25%.

Next, for each of the obtained heat exchangers, hematocrit ()Ie is applied from the external fluid supply port 3a to the outside of the hollow fiber.
Bovine blood having a matrix value of 35% and water were flowed inside the hollow fibers from the internal fluid supply port 5a to perform heat exchange.

Heat exchange efficiency E when the water flow rate is 9.5R,/min, the blood temperature at the supply port 3a is 30°C, and the water temperature at the supply port 5a is 40°C.
was calculated using the formula shown below. The heat exchange efficiency with respect to the blood flow rate (n/min,) obtained with three randomly selected exchanges LtE1-1, 1-2, 1-:l is calculated as the first
The table also shows the change in heat exchange efficiency depending on the blood flow rate in FIG.

Here, E: heat exchange efficiency, T day x: blood temperature on the supply port 3a side, Tea: blood temperature on the discharge port 3b side, Tw! , supply port 5
This is the water temperature on the a side.

Example 2 A large number of heat exchangers were manufactured in the same manner as in Example 1, except that the number of twists of the polyethylene hollow fibers was 10 T/II+, and heat exchange was performed. Randomly selected heat exchanger/a2-
The heat exchange efficiencies obtained in Examples 1, 2-2, and 2-3 are shown in Table 1 and FIG. 3, respectively.

Comparative Example 1 A large number of heat exchangers were manufactured in the same manner as in Example 1, except that the polyethylene hollow fibers were not twisted, and heat exchange was performed. Randomly selected heat exchanger/L11-1.11-
The heat exchange efficiency obtained in No. 2 is shown in Table 1 and FIG. 3, respectively. In addition, the filling rate of hollow fibers in this case is also 25%.
Met.

Summarizing the above results, the heat exchangers obtained in Examples 1 and 2 had higher heat exchange efficiency than the exchanger obtained in Comparative Example 1 for any blood flow m. In particular, from the comparison with Comparative Example 1, the heat exchangers obtained in Example 1 and Example 2 are as good as the exchanger obtained in Comparative Example 1 at any blood flow rate. A higher heat exchange efficiency was obtained. In particular, in comparison with Comparative Example 1, in the hollow fiber module of the present invention, higher efficiency was obtained even at the same hollow fiber filling rate due to the non-linear shape of the hollow fibers.

〔Effect of the invention〕

In the hollow fiber module of the present invention, since the filled hollow fibers have a non-linear shape, the laminar flow state of the fluid inside and outside the hollow fibers is disturbed, so the film resistance on the surface of the hollow fibers is reduced. can be reduced and higher hollow fiber separation and exchange efficiency can be obtained.

In addition, in the module of the present invention, even when the filling rate of the hollow fibers is low, the bulkiness due to the non-linear shape of the hollow fibers makes it easy to obtain good dispersion of the hollow fibers within the module, which was previously difficult. , and its shape is maintained, resulting in excellent performance stability.Moreover, the non-linear shape of the hollow fibers prevents the occurrence of specific flow paths, ie, channeling, within the module.

Therefore, when the fluid outside the hollow fiber is blood, the blood can be treated by drop blood removal, so the hollow fiber module of the present invention is particularly excellent for blood treatment.

On the other hand, even when the filling rate is increased, since the hollow fibers have a non-linear shape, appropriate spacing occurs between each hollow fiber in the hollow fiber bundle, and the liquid easily flows into the inside of the hollow fiber bundle. Therefore, the utilization efficiency of hollow fibers can be significantly improved.

[Brief explanation of drawings]

FIGS. 1 and 2 are schematic cross-sectional views showing one embodiment of the hollow fiber module of the present invention, and FIG. 3 is a schematic cross-sectional view of the heat exchanger with respect to the blood flow rate in each of the heat exchangers manufactured in the example and comparative example. It is a graph showing changes in exchange efficiency. 1: Hollow fiber la: Hollow fiber opening end 2: Fixing member 3: Housing 3a: External fluid supply port
3b: External fluid outlet 4: Fluid reservoir 5a, 5b = Internal fluid supply or outlet 6: Hollow fiber support member

Claims (1)

[Claims] 1) A hollow fiber characterized by being formed by converging and fixing a large number of open ends of a non-linear hollow fiber having a large number of curved portions in a housing with a fixing member while maintaining the open state. yarn module. 2) A large number of the hollow fibers are focused and fixed by a first fixing member with one open end of each holding the open state, and a second fixing member with the other open end keeping the open state. The hollow fiber module according to claim 1, wherein the hollow fiber module is arranged between these fixing members and is focused and fixed by. 3) The hollow fiber module according to claim 1, wherein a large number of the hollow fibers are fixed together by one fixing member while keeping both ends of each hollow fiber open. 4) The method according to claim 1, wherein a large number of the hollow fibers, each of which has only one end in an open state, are converged and fixed from the open end thereof by one fixing member while maintaining the open state. Hollow fiber module. 5) The outer diameter of the hollow fiber is within the range of 100 to 2000 μm, and the non-linear shape is formed by real twisting or false twisting, and the number of twists or false twists at that time is 10 to 200 T/
m, and the ratio of the length in a non-linear shape to the length in a straight line is 100.1% to 150.0
% of the hollow fiber module according to any one of claims 1 to 4.