阅读说明：本技术 脱气系统、液体的脱气方法、脱气模块、脱气系统的制造方法及天然资源的生产方法 (Degassing system, method for degassing liquid, degassing module, method for manufacturing degassing system, and method for producing natural resource ) 是由 山本航 猪狩克彦 佐野贤治 大井和美 于 2019-09-27 设计创作，主要内容包括：一种脱气系统,该脱气系统具有脱气单元,该脱气单元是对液体进行脱气的多个脱气模块连结而成的,多个脱气模块各自均具有：中空纤维膜束,该中空纤维膜束具有配置于供给液体的液体供给路的周围的多条中空纤维膜；以及模块容器,该模块容器收纳中空纤维膜束,脱气单元具有连结供给管,该连结供给管将多个脱气模块的液体供给路以串联的方式连接,在该连结供给管的与多个脱气模块对应的位置形成有供液体经过的开口,以将液体并列地向多个脱气模块的中空纤维膜束供给,脱气单元构成为,从连结供给管的供给液体的供给口至下游侧脱气模块的排出口的液体的压力损失比从供给口至上游侧脱气模块的排出口的液体的压力损失大。(A degassing system having a degassing unit in which a plurality of degassing modules for degassing a liquid are connected, each of the plurality of degassing modules comprising: a hollow fiber membrane bundle having a plurality of hollow fiber membranes arranged around a liquid supply path for supplying a liquid; and a module container that houses the hollow fiber membrane bundle, wherein the degassing unit has a connection supply pipe that connects the liquid supply paths of the plurality of degassing modules in series, and wherein an opening through which the liquid passes is formed in the connection supply pipe at a position corresponding to the plurality of degassing modules so as to supply the liquid to the hollow fiber membrane bundles of the plurality of degassing modules in parallel, and wherein the degassing unit is configured such that a pressure loss of the liquid from a supply port of the supply liquid of the connection supply pipe to a discharge port of the downstream degassing module is greater than a pressure loss of the liquid from the supply port to the discharge port of the upstream degassing module.)

1. A degassing system, wherein,

the degassing system comprises a degassing unit formed by connecting a plurality of degassing modules for degassing liquid,

the plurality of degassing modules each have:

a hollow fiber membrane bundle having a plurality of hollow fiber membranes arranged around a liquid supply path for supplying a liquid; and

a module container that houses the hollow fiber membrane bundle, the module container being formed with a discharge port for discharging the liquid,

the degassing unit has a connection supply pipe that connects the liquid supply paths of the plurality of degassing modules in series, and an opening through which the liquid passes is formed in the connection supply pipe at a position corresponding to the plurality of degassing modules so that the liquid is supplied to the hollow fiber membrane bundles of the plurality of degassing modules in parallel,

the plurality of degassing modules include an upstream side degassing module and a downstream side degassing module disposed on a downstream side of the upstream side degassing module,

the degassing unit is configured such that a pressure loss of the liquid from a supply port of the connection supply pipe, through which the liquid is supplied, to the discharge port of the downstream-side degassing module is greater than a pressure loss of the liquid from the supply port to the discharge port of the upstream-side degassing module.

2. The degassing system of claim 1,

the degassing unit is configured such that a pressure loss of the liquid from the opening formed at a position corresponding to the downstream-side degassing module to the discharge port of the downstream-side degassing module is larger than a pressure loss of the liquid from the opening formed at a position corresponding to the upstream-side degassing module to the discharge port of the upstream-side degassing module.

3. The degassing system according to claim 1 or 2,

the connection supply pipe is configured such that a pressure loss of the liquid at a position corresponding to the downstream degassing module is greater than a pressure loss of the liquid at a position corresponding to the upstream degassing module.

4. The degassing system according to any one of claims 1 to 3,

the inner diameter of the connection supply pipe at a position corresponding to the downstream-side degassing module is smaller than the inner diameter of the connection supply pipe at a position corresponding to the upstream-side degassing module.

5. The degassing system according to any one of claims 1 to 4,

the opening formed at a position corresponding to the downstream degassing module is configured such that a pressure loss of the liquid is greater than a pressure loss of the liquid formed at the opening at a position corresponding to the upstream degassing module.

6. The degassing system according to any one of claims 1 to 5,

the total area of the openings formed at the position corresponding to the downstream-side degassing module is smaller than the total area of the openings formed at the position corresponding to the upstream-side degassing module.

7. The degassing system according to any one of claims 1 to 6,

the number of the openings formed at a position corresponding to the downstream side degassing module is smaller than the number of the openings formed at a position corresponding to the upstream side degassing module.

8. The degassing system according to any one of claims 1 to 7,

the size of the opening formed at a position corresponding to the downstream-side degassing module is smaller than the size of the opening formed at a position corresponding to the upstream-side degassing module.

9. The degassing system according to any one of claims 1 to 8,

each of the plurality of degassing modules further includes a module inner tube disposed on an inner peripheral side of the hollow fiber membrane bundle, the module inner tube having an inner tube opening through which the liquid passes,

the inner tube opening of the downstream degassing module is configured such that a pressure loss of the liquid is greater than a pressure loss of the liquid at the inner tube opening of the upstream degassing module.

10. The degassing system according to any one of claims 1 to 9,

the hollow fiber membrane bundle of the downstream degassing module is configured such that a pressure loss of the liquid is greater than a pressure loss of the liquid of the hollow fiber membrane bundle of the upstream degassing module.

11. The degassing system according to any one of claims 1 to 10,

the density of the plurality of hollow fiber membranes in the downstream side degassing module is higher than the density of the plurality of hollow fiber membranes in the upstream side degassing module.

12. The degassing system according to any one of claims 1 to 11,

the thickness of the hollow fiber membrane bundle in the downstream side degassing module is thicker than the thickness of the hollow fiber membrane bundle in the upstream side degassing module.

13. The degassing system according to any one of claims 1 to 12,

the hollow fiber membrane bundle is formed by winding a fabric woven by the plurality of hollow fiber membranes as weft yarns by warp yarns around the liquid supply path,

the winding pressure of the web in the downstream side degassing module is higher than the winding pressure of the web in the upstream side degassing module.

14. The degassing system according to any one of claims 1 to 13,

the hollow fiber membrane bundle is formed by winding a woven fabric, which is woven by the warp yarns from the plurality of hollow fiber membranes as weft yarns, around the liquid supply path so that the plurality of hollow fiber membranes extend in the axial direction of the liquid supply path,

the pitch of the warp yarns in the downstream side degassing module is longer than the pitch of the warp yarns in the upstream side degassing module.

15. The degassing system according to any one of claims 1 to 14,

the outer diameter of the hollow fiber membranes in the downstream side degassing module is larger than the outer diameter of the hollow fiber membranes in the upstream side degassing module.

16. The degassing system according to any one of claims 1 to 15,

the hollow fiber membranes in the downstream-side degassing module have higher hydrophilicity than the hollow fiber membranes in the upstream-side degassing module.

17. The degassing system according to any one of claims 1 to 16,

the discharge port of the downstream degassing module is configured such that a pressure loss of the liquid is greater than a pressure loss of the liquid at the discharge port of the upstream degassing module.

18. The degassing system according to any one of claims 1 to 17,

the total area of the discharge ports of the downstream side degassing module is smaller than the total area of the discharge ports of the upstream side degassing module.

19. The degassing system according to any one of claims 1 to 18,

the number of the discharge ports of the downstream side degassing module is smaller than the number of the discharge ports of the upstream side degassing module.

20. The degassing system according to any one of claims 1 to 19,

the size of the discharge port of the downstream side degassing module is smaller than the size of the discharge port of the upstream side degassing module.

21. The degassing system according to any one of claims 1 to 20,

the degassing system also has:

a housing that houses a degassing unit, the housing being formed with an inlet through which liquid is supplied from the outside and an outlet through which the liquid is discharged to the outside; and

and a suction pipe which communicates with the insides of the plurality of hollow fiber membranes of the plurality of degassing modules to suck the insides of the plurality of hollow fiber membranes.

22. A method for degassing a liquid, wherein,

the degassing system according to any one of claims 1 to 21, wherein a liquid is supplied from the connection supply pipe to the liquid supply paths of the plurality of degassing modules, and the inside of the plurality of hollow fiber membranes of each of the plurality of degassing modules is depressurized, thereby degassing the liquid.

23. A degassing module for use in a degassing system according to any one of claims 1 to 21, wherein,

the degassing module has:

a hollow fiber membrane bundle having a plurality of hollow fiber membranes arranged around a liquid supply path for supplying a liquid; and

and a module container that houses the hollow fiber membrane bundle, the module container being formed with a discharge port for discharging the liquid.

24. A method of manufacturing a degassing system, wherein,

preparing a connection supply pipe and a plurality of degassing modules each having: a hollow fiber membrane bundle having a plurality of hollow fiber membranes arranged around a liquid supply path for supplying a liquid; and a module container which accommodates the hollow fiber membrane bundle, in which a discharge port for discharging the liquid is formed, and a plurality of openings through which the liquid passes are formed in the connecting supply pipe,

inserting the connection supply pipe into the liquid supply paths of the plurality of degassing modules, connecting the liquid supply paths of the plurality of degassing modules in series by the connection supply pipe, and arranging the plurality of openings at positions corresponding to the plurality of degassing modules so that the liquid is supplied to the hollow fiber membrane bundles of the plurality of degassing modules in parallel,

when one of the plurality of degassing modules is an upstream-side degassing module and one of the plurality of degassing modules disposed on the downstream side of the upstream-side degassing module is a downstream-side degassing module, a pressure loss of the liquid from a supply port of the connection supply pipe, through which the liquid is supplied, to the discharge port of the downstream-side degassing module is set to be greater than a pressure loss of the liquid from the supply port to the discharge port of the upstream-side degassing module.

25. A method for producing a natural resource, wherein,

the method comprises the following steps: a degassing step of supplying a liquid from the connection supply pipe to the liquid supply paths of the plurality of degassing modules in the degassing system according to any one of claims 1 to 21, and degassing the liquid by reducing the pressure inside the plurality of hollow fiber membranes of each of the plurality of degassing modules; and a pressure-feeding step of feeding the liquid degassed in the degassing step into a natural resource exploitation site.

Technical Field

One aspect of the present invention relates to a degassing system including a degassing unit in which a plurality of degassing modules are connected, a method for degassing a liquid using the degassing system, a degassing module used in the degassing system, a method for manufacturing the degassing system, and a method for producing a natural resource.

Background

A degassing module for degassing a liquid using a hollow fiber membrane has been known. In order to cope with an increase in size or an increase in flow rate, a degassing system in which a plurality of degassing modules are connected to each other is also known.

Patent document 1 discloses a module in which a plurality of fluid contactors having hollow fiber membranes are connected. In this module, as the plurality of fluid contactors, the same fluid contactor is used. In this module, the inlet manifold for supplying the liquid is branched in correspondence with the plurality of fluid contactors, and is connected to each of the plurality of fluid contactors independently. Thus, liquid supplied to the inlet manifold is supplied in parallel to the plurality of fluid contactors.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 4593719

Disclosure of Invention

Problems to be solved by the invention

However, in the case of flowing the liquid to 1 degassing module and in the case of flowing N times the liquid to a degassing system in which N degassing modules are linked, it is considered that the degassing performance is the same. However, the inventors of the present invention have found, through research, that when a degassing system in which liquid supply lines of a plurality of degassing modules are connected in series and liquid is supplied to hollow fiber membranes of the plurality of degassing modules in parallel is used as a degassing system, degassing performance is lowered as compared with a case where liquid is caused to flow to 1 degassing module.

Accordingly, an object of one aspect of the present invention is to provide a degassing system capable of improving the overall degassing performance, a method of degassing a liquid using the degassing system, a degassing module used in the degassing system, a method of manufacturing the degassing system, and a method of producing a natural resource.

Means for solving the problems

The present inventors have further studied to achieve the above object and have obtained the following findings.

In a degassing system in which a plurality of degassing modules are connected, it has been conventionally considered that the same amount of liquid flows to each degassing module. However, in practice, in a degassing system in which liquid supply lines of a plurality of degassing modules are connected in series and liquid is supplied to hollow fiber membranes of the plurality of degassing modules in parallel, the flow rates of the liquid flowing through the respective degassing modules are different between the upstream side and the downstream side. The reason for this is considered as follows.

That is, in such a degassing system, since the liquid flows out from the liquid supply path to the hollow fiber side, the flow rate of the liquid decreases from the upstream side to the downstream side. Then, the pressure of the liquid increases from the upstream side toward the downstream side. Thus, the more downstream the flow of liquid to the degassing module is, the more upstream the flow of liquid to the degassing module is. Since the degassing performance of the degassing module greatly varies depending on the flow rate of the liquid, the flow rate of the liquid is deviated between the upstream degassing module and the downstream degassing module, and it is considered that the degassing performance of the entire degassing system is deteriorated.

From such a situation, it is concluded that the degassing performance of the entire degassing system can be improved by reducing the deviation of the flow rate of the liquid between the upstream degassing module and the downstream degassing module.

A degassing system according to an aspect of the present invention includes a degassing unit in which a plurality of degassing modules for degassing a liquid are connected, each of the plurality of degassing modules including: a hollow fiber membrane bundle having a plurality of hollow fiber membranes arranged around a liquid supply path for supplying a liquid; and a module container that houses the hollow fiber membrane bundle and has a discharge port formed therein for discharging liquid, wherein the degassing unit has a connection supply pipe that connects the liquid supply paths of the plurality of degassing modules in series, and an opening through which the liquid passes is formed at a position of the connection supply pipe corresponding to the plurality of degassing modules so that the liquid is supplied to the hollow fiber membrane bundle of the plurality of degassing modules in parallel, and the plurality of degassing modules include an upstream-side degassing module and a downstream-side degassing module disposed downstream of the upstream-side degassing module, and wherein the degassing unit is configured such that a pressure loss of the liquid from the supply port of the supply liquid of the connection supply pipe to the discharge port of the downstream-side degassing module is greater than a pressure loss of the liquid from the supply port to the discharge port of the upstream-side degassing module.

In this degassing system, the liquid is supplied in parallel to the hollow fiber membrane bundles of the plurality of degassing modules by a connection supply pipe connecting the liquid supply paths of the plurality of degassing modules in series. However, the pressure loss of the liquid from the supply port of the connection supply pipe to the discharge port of the downstream-side degassing module is larger than the pressure loss of the liquid from the supply port of the connection supply pipe to the discharge port of the upstream-side degassing module. Therefore, this difference in pressure loss acts to cancel out the difference in flow velocity and pressure in the flow direction of the liquid. As a result, the deviation of the flow rate of the liquid between the upstream degassing module and the downstream degassing module is reduced, and therefore the degassing performance of the entire degassing system can be improved.

The degassing unit may be configured such that a pressure loss of the liquid from the opening formed at a position corresponding to the downstream-side degassing module to the discharge port of the downstream-side degassing module is greater than a pressure loss of the liquid from the opening formed at a position corresponding to the upstream-side degassing module to the discharge port of the upstream-side degassing module. By setting the pressure loss of the liquid from the opening formed at the position corresponding to the downstream-side degassing module to the discharge port of the module container to be larger than the pressure loss of the liquid from the opening formed at the position corresponding to the upstream-side degassing module to the discharge port of the module container, the liquid is less likely to flow to the downstream-side degassing module than to the upstream-side degassing module. This can improve the degassing performance of the entire degassing system.

The connection supply pipe may be configured such that a pressure loss of the liquid at a position corresponding to the downstream degassing module is greater than a pressure loss of the liquid at a position corresponding to the upstream degassing module. By setting the pressure loss of the liquid at the position corresponding to the downstream-side degassing module of the connection supply pipe to be greater than the pressure loss of the liquid at the position corresponding to the upstream-side degassing module of the connection supply pipe, the pressure loss of the liquid from the supply port of the connection supply pipe to the discharge port of the downstream-side degassing module can be set to be greater than the pressure loss of the liquid from the supply port of the connection supply pipe to the discharge port of the upstream-side degassing module. This can improve the degassing performance of the entire degassing system.

The inner diameter of the connection supply pipe at the position corresponding to the downstream-side degassing module may be smaller than the inner diameter of the connection supply pipe at the position corresponding to the upstream-side degassing module. With this arrangement, the pressure loss of the liquid at the position corresponding to the downstream-side degassing module of the connection supply pipe is greater than the pressure loss of the liquid at the position corresponding to the upstream-side degassing module of the connection supply pipe, and therefore, the degassing performance of the entire degassing system can be improved.

The opening formed at the position corresponding to the downstream degassing module may be configured such that the pressure loss of the liquid is greater than the pressure loss of the liquid formed at the opening at the position corresponding to the upstream degassing module. By setting the pressure loss of the liquid formed at the opening corresponding to the downstream-side degassing module to be greater than the pressure loss of the liquid formed at the opening corresponding to the upstream-side degassing module, the pressure loss of the liquid from the supply port connected to the supply pipe to the discharge port of the downstream-side degassing module can be set to be greater than the pressure loss of the liquid from the supply port connected to the supply pipe to the discharge port of the upstream-side degassing module.

The total area of the openings formed at the position corresponding to the downstream-side degassing module may be smaller than the total area of the openings formed at the position corresponding to the upstream-side degassing module. In addition, the number of openings formed at a position corresponding to the downstream side degassing module may be smaller than the number of openings formed at a position corresponding to the upstream side degassing module. Further, the size of the opening formed at the position corresponding to the downstream side degassing module may be smaller than the size of the opening formed at the position corresponding to the upstream side degassing module. With this arrangement, the pressure loss of the liquid formed at the opening corresponding to the downstream-side degassing module is greater than the pressure loss of the liquid formed at the opening corresponding to the upstream-side degassing module, and therefore, the degassing performance of the entire degassing system can be improved.

Each of the plurality of degassing modules may further include a module inner tube, the hollow fiber membrane bundle being disposed around the module inner tube, an inner tube opening through which the liquid passes being formed in the module inner tube, and the inner tube opening of the downstream degassing module may be configured such that a pressure loss of the liquid is greater than a pressure loss of the liquid at the inner tube opening of the upstream degassing module. In the case where each of the plurality of degassing modules has a module inner tube, the pressure loss of the liquid at the opening of the inner tube of the downstream-side degassing module is set to be greater than the pressure loss of the liquid at the opening of the inner tube of the upstream-side degassing module, whereby the pressure loss of the liquid from the supply port connected to the supply pipe to the discharge port of the downstream-side degassing module can be set to be greater than the pressure loss of the liquid from the supply port connected to the supply pipe to the discharge port of the upstream-side degassing module.

The hollow fiber membrane bundle of the downstream degassing module may be configured such that the pressure loss of the liquid is greater than the pressure loss of the liquid of the hollow fiber membrane bundle of the upstream degassing module. By setting the pressure loss of the liquid at the hollow fiber membrane bundle of the downstream-side degassing module to be greater than the pressure loss of the liquid at the hollow fiber membrane bundle of the upstream-side degassing module, the pressure loss of the liquid from the supply port of the connection supply pipe to the discharge port of the downstream-side degassing module can be set to be greater than the pressure loss of the liquid from the supply port of the connection supply pipe to the discharge port of the upstream-side degassing module. This can improve the degassing performance of the entire degassing system.

The density of the plurality of hollow fiber membranes in the downstream-side degassing module may be higher than the density of the plurality of hollow fiber membranes in the upstream-side degassing module. The thickness of the hollow fiber membrane bundle in the downstream degassing module may be larger than the thickness of the hollow fiber membrane bundle in the upstream degassing module. The hollow fiber membrane bundle may be formed by winding a woven fabric, which is woven by a plurality of hollow fiber membranes as weft yarns, around the liquid supply path by using warp yarns, and the winding pressure of the woven fabric in the downstream degassing module may be higher than the winding pressure of the woven fabric in the upstream degassing module. The hollow fiber membrane bundle may be a woven fabric in which a plurality of hollow fiber membranes as weft yarns are woven by warp yarns and wound around the periphery of the liquid supply path such that the plurality of hollow fiber membranes extend in the axial direction of the liquid supply path, and the pitch of the warp yarns in the downstream-side degassing module may be longer than the pitch of the warp yarns in the upstream-side degassing module. Further, the outer diameter of the hollow fiber membrane in the downstream side degassing module may be larger than the outer diameter of the hollow fiber membrane in the upstream side degassing module. In addition, the hollow fiber membranes in the downstream side degassing module may have higher hydrophilicity than the hollow fiber membranes in the upstream side degassing module. With this arrangement, the pressure loss of the liquid in the hollow fiber membrane bundle of the downstream-side degassing module is greater than the pressure loss of the liquid in the hollow fiber membrane bundle of the upstream-side degassing module, and therefore the degassing performance of the entire degassing system can be improved.

The discharge port of the module container of the downstream degassing module may be configured such that a pressure loss of the liquid is greater than a pressure loss of the liquid at the discharge port of the module container of the upstream degassing module. By setting the pressure loss of the liquid at the discharge port of the downstream-side degassing module to be greater than the pressure loss of the liquid at the discharge port of the upstream-side degassing module, the pressure loss of the liquid from the supply port of the connection supply pipe to the discharge port of the downstream-side degassing module can be set to be greater than the pressure loss of the liquid from the supply port of the connection supply pipe to the discharge port of the upstream-side degassing module. This can improve the degassing performance of the entire degassing system.

The total area of the discharge ports of the downstream-side degassing module may be smaller than the total area of the discharge ports of the upstream-side degassing module. Further, the number of discharge ports of the downstream side degassing module may be smaller than the number of discharge ports of the upstream side degassing module. Further, the size of the discharge port of the downstream degassing module may be smaller than the size of the discharge port of the upstream degassing module. With this arrangement, the pressure loss of the liquid at the discharge port of the downstream-side degassing module is greater than the pressure loss of the liquid at the discharge port of the upstream-side degassing module, and therefore the degassing performance of the entire degassing system can be improved.

The degassing system of one aspect of the present invention further has: a housing that houses a degassing unit, the housing being formed with an inlet through which liquid is supplied from the outside and an outlet through which the liquid is discharged to the outside; and a suction pipe which communicates with the insides of the plurality of hollow fiber membranes of the plurality of degassing modules in order to suck the insides of the plurality of hollow fiber membranes. By having such a housing and a suction pipe, it is possible to appropriately degas the liquid in the degassing unit and appropriately recover the liquid degassed in the degassing unit.

In the liquid degassing method according to one aspect of the present invention, in the above-described arbitrary degassing system, the liquid is supplied from the connection supply pipe to the liquid supply paths of the plurality of degassing modules, and the inside of the plurality of hollow fiber membranes of each of the plurality of degassing modules is depressurized, thereby degassing the liquid.

A degassing module according to an aspect of the present invention is used in any of the above degassing systems, and includes: a hollow fiber membrane bundle having a plurality of hollow fiber membranes arranged around a liquid supply path for supplying a liquid; and a module container that houses the hollow fiber membrane bundle, the module container being formed with a discharge port for discharging liquid.

In a method of manufacturing a degassing system according to an aspect of the present invention, a connection supply pipe and a plurality of degassing modules each having: a hollow fiber membrane bundle having a plurality of hollow fiber membranes arranged around a liquid supply path for supplying a liquid; and a module container for accommodating the hollow fiber membrane bundle, the module container being formed with a discharge port for discharging a liquid, a plurality of openings through which the liquid passes are formed in the connection supply pipe, the connection supply pipe is inserted into the liquid supply paths of the plurality of degassing modules, the liquid supply paths of the plurality of degassing modules are connected in series by the connection supply pipe, and a plurality of openings are arranged at positions corresponding to the plurality of degassing modules so that the liquid is supplied to the hollow fiber membrane bundles of the plurality of degassing modules in parallel, when one of the plurality of degassing modules is an upstream-side degassing module and one of the plurality of degassing modules disposed on the downstream side of the upstream-side degassing module is a downstream-side degassing module, the pressure loss of the liquid from the supply port for supplying the liquid to the discharge port of the downstream degassing module, which is connected to the supply pipe, is set to be greater than the pressure loss of the liquid from the supply port to the discharge port of the upstream degassing module.

The method for producing a natural resource according to one aspect of the present invention has: a degassing step of, in the above-described arbitrary degassing system, supplying a liquid from a connection supply pipe to the liquid supply paths of the plurality of degassing modules, and degassing the liquid by depressurizing the insides of the plurality of hollow fiber membranes of each of the plurality of degassing modules; and a pressure-feeding step of feeding the liquid degassed in the degassing step into a natural resource exploitation site.

ADVANTAGEOUS EFFECTS OF INVENTION

According to one aspect of the present invention, the degassing performance of the entire degassing system can be improved.

Drawings

Fig. 1 is a schematic sectional view of a degassing system according to an embodiment.

Fig. 2 is a schematic sectional view taken along line II-II shown in fig. 1.

Fig. 3 is a schematic front view of a degassing module.

Fig. 4 is a schematic cross-sectional view of a degassing module.

Fig. 5 is a schematic cross-sectional view of an end portion of a hollow fiber membrane bundle.

Fig. 6 is a schematic view of an abstraction of the degassing unit shown in fig. 1.

Fig. 7 is a table showing an example of the flow rate of the liquid flowing to each degassing module in the degassing system of the reference example.

Fig. 8 is a graph for explaining the flow rate and pressure of the liquid in each degassing unit.

Detailed Description

In the following description, the same elements or similar elements having the same function are denoted by the same reference numerals, and redundant description thereof is omitted.

The degassing system of the present embodiment is a system for degassing a liquid. Examples of the liquid to be degassed by the degassing system include water. As shown in fig. 1 and 2, a degassing system 1 of the present embodiment includes a degassing unit 3 in which a plurality of degassing modules 2 are connected, a casing 4 that houses the degassing unit 3, and a suction pipe 5.

[ degassing Module ]

As shown in fig. 1 to 4, the degassing module 2 includes a module inner tube 11, a hollow fiber membrane bundle 12, and a module container 13.

The module inner tube 11 is a tube having a liquid supply path 10 formed on the inner peripheral side thereof for supplying a liquid such as water. The module inner pipe 11 is formed in a circular pipe shape extending in a straight line, for example. The module inner tube 11 has a plurality of inner tube openings 11a formed therein. The inner tube opening 11a is used for passing the liquid supplied to the liquid supply path 10 of the module inner tube 11. The number, position, size, and the like of the inner tube openings 11a are not particularly limited.

The hollow fiber membrane bundle 12 has a plurality of hollow fiber membranes 14 arranged around the module inner tube 11. Therefore, the liquid supply path 10 is disposed on the inner peripheral side of the hollow fiber membrane bundle 12. The hollow fiber membrane bundle 12 is configured by, for example, bundling a plurality of hollow fiber membranes 14 into a cylindrical shape such as a cylindrical shape. The hollow fiber membranes 14 are hollow fiber-like membranes that are permeable to gas but not to liquid. The hollow fiber membrane bundle 12 deaerates the liquid flowing out from the inner tube opening 11a of the module inner tube 11 by depressurizing the inside of the hollow fiber membranes 14.

The material of the hollow fiber membrane 14 is not particularly limited, and may be in the form of a membrane or a membrane. Examples of the material of the hollow fiber membrane 14 include polyolefin resins such as polypropylene and poly (4-methyl-1-pentene), silicone resins such as polydimethylsiloxane and a copolymer thereof, and fluorine resins such as PTFE and polyvinylidene fluoride. Examples of the membrane shape (shape of the side wall) of the hollow fiber membrane 14 include a porous membrane, a microporous membrane, and a non-porous homogeneous membrane (non-porous membrane). Examples of the membrane form of the hollow fiber membrane 14 include a symmetric membrane (homogeneous membrane) in which the chemical structure or the physical structure of the whole membrane is homogeneous, and an asymmetric membrane (heterogeneous membrane) in which the chemical structure or the physical structure of the membrane is different depending on the part of the membrane. An asymmetric membrane (heterogeneous membrane) is a membrane having a dense layer that is not porous and a porous layer. In this case, the dense layer may be formed in a surface layer portion of the membrane or in a portion of the membrane such as the inside of the porous membrane. The heterogeneous membrane also includes a composite membrane having a different chemical structure, such as a multilayer structure membrane having a 3-layer structure.

The hollow fiber membrane bundle 12 can be formed of, for example, a woven fabric (not shown) in which a plurality of hollow fiber membranes 14 as weft yarns are woven by warp yarns. The fabric is also called a hollow fiber membrane sheet, and a plurality of hollow fiber membranes 14 are woven in a curtain shape. The fabric is comprised of, for example, 30 to 90 hollow fiber membranes 14 per inch. The fabric can be wound around the module inner tube 11 (liquid supply path) so as to extend in the axial direction of the module inner tube 11 (liquid supply path 10) through the plurality of hollow fiber membranes 14, thereby forming the cylindrical hollow fiber membrane bundle 12.

The module container 13 is a container for accommodating the hollow fiber membrane bundle 12. The region between the module inner tube 11 and the module container 13 is a degassing region a in which the liquid is degassed by the hollow fiber membrane bundle 12. The module container 13 is formed in a cylindrical shape extending in the axial direction of the module inner tube 11 (liquid supply path 10), for example, and has both ends opened. The module case 13 is formed with a plurality of discharge ports 13 a. The discharge port 13a is used to discharge the liquid passing through the hollow fiber membrane bundle 12 in the degassing region a from the module container 13 (degassing module 2). The number, position, size, and the like of the discharge ports 13a are not particularly limited.

As shown in fig. 5, both side end portions 12a of the hollow fiber membrane bundle 12 are fixed to the module inner tube 11 and the module container 13 by the seal portions 15.

The sealing portion 15 is formed of, for example, resin. Examples of the resin used for the sealing portion 15 include polyolefin resins such as epoxy resin, urethane resin, ultraviolet curable resin, polyethylene, and polypropylene. The seal 15 fills the entire region between the module inner tube 11 and the module container 13 except for the inside of the hollow fiber membranes 14. That is, the sealing portions 15 are filled between the hollow fiber membranes 14, between the hollow fiber membrane bundle 12 and the module inner tube 11, and between the hollow fiber membranes 14 and the module container 13, but are not filled inside the hollow fiber membranes 14. Therefore, the inside of the hollow fiber membranes 14 is opened from the sealing part 15 to both end sides of the degassing module 2, and the inside of the hollow fiber membranes 14 can be sucked from both end sides of the degassing module 2. That is, the openings at both ends of the module container 13 are air suction openings for opening or exposing the inside of the hollow fiber membranes 14 so that the inside of the hollow fiber membranes 14 can be sucked and decompressed.

[ degassing Unit ]

As shown in fig. 1 to 6, the degassing unit 3 includes a connection supply pipe 6 connecting the liquid supply paths 10 of the plurality of degassing modules 2 in series. The connection supply pipe 6 is 1 long pipe connected to the plurality of degassing modules 2, and forms the liquid supply path 10 of the plurality of degassing modules 2 on the inner peripheral side thereof. Therefore, the plurality of degassing modules 2 are connected in series by the connection supply pipe 6 in appearance. The number of degassing modules 2 constituting the degassing unit 3 is not particularly limited, and in the following description, a configuration in which 4 degassing modules 2 are connected will be described as an example. The 4 degassing modules 2 are referred to as a degassing module 2A, a degassing module 2B, a degassing module 2C, and a degassing module 2D in order of the flow direction of the liquid in the connection supply pipe 6. The degassing module 2A is the degassing module 2 disposed on the most upstream side, and the degassing module 2D is the degassing module 2 disposed on the most downstream side. The degassing unit 3 is provided upright in the vertical direction, for example, so that the liquid flows upward from below through the connection supply pipe 6. In this case, the degassing module 2A disposed on the most upstream side is disposed on the lowermost side, and the degassing module 2D disposed on the most downstream side is disposed on the uppermost side.

A supply port 6a for supplying liquid to the connection supply pipe 6 is formed at the upstream end of the connection supply pipe 6. The downstream end of the connecting supply pipe 6 is sealed. The inner peripheral side of the connecting supply pipe 6 forming the liquid supply path 10 of the plurality of degassing modules 2 penetrates from the upstream side to the downstream side. Therefore, a member serving as resistance to the flow of the liquid may be disposed on the inner peripheral side of the connection supply pipe 6 (the module inner pipe 11 of each degassing module 2), but a member for sealing the connection supply pipe 6 and blocking the flow of the liquid may not be disposed. The liquid supplied from the supply port 6a is supplied in series to the liquid supply paths 10 of the plurality of degassing modules 2 by the connecting supply pipe 6.

In the connection supply pipe 6, openings 6b through which the liquid passes are formed at positions corresponding to the plurality of degassing modules 2 so as to supply the liquid to the hollow fiber membrane bundles 12 of the plurality of degassing modules 2 in parallel. Therefore, the liquid supplied to the supply port 6a of the connection supply pipe 6 is supplied (flows out) from the opening 6b formed at a position corresponding to each degassing module 2 to the degassing region a of each degassing module 2. Thereby, the liquid is supplied in parallel to the hollow fiber membrane bundles 12 of the plurality of degassing modules 2.

The degassing modules 2 and the connecting supply pipe 6 may be in close contact with each other or may be separated from each other. When each degassing module 2 and the connection supply pipe 6 are in close contact with each other, the inner tube opening 11a of each degassing module 2 and the opening 6b of the connection supply pipe 6 are formed at positions where they at least partially overlap each other, so that the liquid can be supplied from the connection supply pipe 6 to the degassing region a of each degassing module 2. On the other hand, when each degassing module 2 and the connection supply pipe 6 are separated from each other, a flow path through which liquid flows is formed in a space therebetween, and therefore, regardless of the positional relationship between the inner tube opening 11a of each degassing module 2 and the opening 6b of the connection supply pipe 6, liquid can be supplied from the connection supply pipe 6 to the degassing region a of each degassing module 2.

As shown in fig. 1 and 2, the housing 4 is formed with an inlet 4a through which liquid is supplied from the outside of the housing 4 and an outlet 4b through which liquid is discharged from the housing 4.

The inlet 4a is formed at the lower end of the housing 4, for example. The inlet 4a communicates with a supply port 6a of a connecting supply pipe 6. Therefore, the liquid supplied from the inlet 4a is supplied from the supply port 6a to the connection supply pipe 6.

The outlet 4b is formed at, for example, an upper end portion of the housing 4. The outlet 4b communicates with each discharge port 13a of the module container 13. Therefore, the liquid discharged from each discharge port 13a is discharged from the outlet 4b of the housing 4.

The case 4 is provided with a case sealing portion 7 and a degassing unit supporting portion 8.

The casing seal portion 7 fixes an upstream end portion of the connection supply pipe 6 to an inner peripheral surface of the casing 4. In addition, the casing sealing portion 7 divides the inner region of the casing 4 into an upstream side region B on the inlet 4a side and a downstream side region C on the outlet 4B side by the degassing unit 3. As the case sealing portion 7, for example, a metal such as stainless steel, a Fiber Reinforced Plastic (FRP), or a resin lined with a metal such as iron is used.

The case seal portion 7 is filled in all regions between the connection supply pipe 6 and the case 4 except for the inside of the connection supply pipe 6. That is, the case sealing portion 7 is filled between the connection supply pipe 6 and the case 4, and is not filled inside the connection supply pipe 6. Therefore, the inside of the connection supply pipe 6 is opened from the supply port 6a to the upstream side region B, and the liquid supplied from the inlet 4a to the upstream side region B is supplied only from the supply port 6a to the inside of the connection supply pipe 6 and is supplied from the opening 6B and the inner pipe opening 11a to the degassing region a of each degassing module 2.

The casing sealing portion 7 is disposed upstream of all the discharge ports 13a in the flow direction of the liquid flowing through the connection supply pipe 6. Therefore, the inside of the module container 13 is opened from the discharge port 13a to the downstream region C, and the liquid supplied from the opening 6b and the inner tube opening 11a to the degassing region a is discharged only from the discharge port 13a to the downstream region C and further discharged from the outlet 4b to the outside of the housing 4.

The degassing unit support portion 8 is fixed to the upper end portion of the degassing unit 3 and the case 4, and supports the upper end portion of the degassing unit 3. The degassing unit support portion 8 is formed, for example, in a rod shape extending from the degassing unit 3 to the housing 4, and is not configured to seal between the degassing unit 3 and the housing 4. Therefore, the liquid discharged from the discharge port 13a to the downstream area C is discharged from the outlet 4b to the outside of the casing 4 without being obstructed by the degassing unit support portion 8.

The suction pipe 5 communicates with the insides of the plurality of hollow fiber membranes 14 of the plurality of degassing modules 2 in order to suck (evacuate) the insides of the plurality of hollow fiber membranes 14. The suction pipe 5 penetrates the casing 4 and extends to the outside of the casing 4 for suction by a suction pump such as a vacuum pump provided outside the casing 4. As described above, the inside of the hollow fiber membrane 14 is open from the sealing part 15 to both end sides of the degassing module 2. Thus, the suction pipe 5 is connected to both ends of the degassing module 2 whose inside is open to the hollow fiber membranes 14. By this, the suction pipe 5 is sucked, whereby the inside of the hollow fiber membranes 14 can be sucked from both end sides of the degassing module 2.

Further, as described above, since the plurality of degassing modules 2 are connected in series by the connection supply pipe 6 in appearance, the end surfaces on the target side are arranged to face each other between the degassing modules 2 adjacent to each other along the connection supply pipe 6. Therefore, a suction pipe 5 may be connected to the opposite end surface.

Next, a method of degassing a liquid by the degassing system 1 will be described.

First, a liquid such as water is supplied from the inlet 4a of the casing 4 to the upstream area B of the casing 4. Then, the liquid supplied to the upstream side region B is supplied from the supply port 6a to the connection supply pipe 6, and is supplied to the degassing region a of each degassing module 2 through the opening 6B of the connection supply pipe 6 and the inner pipe opening 11a of each degassing module 2. Thereby, the liquid is supplied in parallel to the hollow fiber membrane bundle 12 of each degassing module 2. In the degassing region a, the liquid supplied from the inner tube opening 11a passes between the plurality of hollow fiber membranes 14 in the hollow fiber membrane bundle 12, and is then discharged from the discharge port 13 a. At this time, the inside of the plurality of hollow fiber membranes 14 is depressurized by sucking the suction pipe 5, and dissolved gas, bubbles, and the like of the liquid passing through between the plurality of hollow fiber membranes 14 are degassed. The degassed liquid is then discharged from the discharge port 13a to the downstream region C, and further discharged from the outlet 4b to the outside of the housing 4.

Here, the flow rate of the liquid flowing to each degassing module was analyzed for the degassing system of the reference example in which 4 degassing modules were connected. The degassing modules are identical, and are a first degassing module, a second degassing module, a third degassing module, and a fourth degassing module in order of the flow direction of the liquid. The analytical software used ANSYS Fleunt Ver.18.2. The liquid is modeled by seawater, and the density is set to 1025.5kg/m³The viscosity was 0.001164 pas. The hollow fiber membrane bundle was modeled by a porous (pressure-resistant flow path), and the pressure coefficient was set to 1.9X 10 based on the analysis value of one degassing module¹⁰. For the analysis for determining the pressure coefficient, EF-040P manufactured by DIC was used. The total flow rate of the liquid supplied to the degassing system of the reference example was set to 4m³H and 24m³Two of these,/h. The analysis result is shown in fig. 7.

As shown in fig. 7, in any total flow rate: the more downstream the flow rate of the liquid to the degassing module increases, and the more upstream the flow rate of the liquid to the degassing module decreases. In addition, the greater the total flow rate, the greater the deviation rate of the flow rate of the liquid flowing to each degassing module. The deviation ratio is the maximum deviation ratio of the positive side and the negative side with respect to the ideal flow rate of the liquid flowing to each degassing module. The ideal flow rate of liquid to each degassing module is the value obtained by dividing the total flow rate by the number of degassing modules (4 in the reference example).

The flow rate and pressure of the liquid flowing to each degassing module were also analyzed. The analysis conditions were the same as described above. Fig. 8 shows a graph in which the analysis result is modeled. The degassing unit shown in fig. 8 corresponds to the degassing unit 3 shown in fig. 6. As shown in fig. 8, since the liquid supplied to the connection supply pipe flows out from the upstream side to the degassing region of the degassing module in order, the flow rate of the liquid flowing through the connection supply pipe decreases from the upstream side to the downstream side. Then, the pressure of the liquid flowing through the connection supply pipe increases from the upstream side toward the downstream side. In other words, the pressure of the liquid flowing through the connection supply pipe decreases from the downstream side toward the upstream side. This can be clarified by the study of the present inventors, but can also be said to be clarified by the bernoulli theorem. In bernoulli's theorem, in a non-viscous, non-compressive, stable flow without an external force, the pressure increases as the velocity decreases. Thus, the more downstream the flow of liquid to the degassing module is, the more upstream the flow of liquid to the degassing module is. The degassing performance of the degassing module varies greatly depending on the flow rate of the liquid. In the degassing system of the reference example, since the deviation of the flow rate of the liquid is large between the degassing module on the upstream side and the degassing module on the downstream side, the degassing performance of the entire degassing system is greatly reduced as compared with the degassing performance of the degassing module of the single body.

Therefore, in the present embodiment, by appropriately setting the pressure loss of the liquid, the deviation of the flow rate of the liquid between the upstream degassing module 2 and the downstream degassing module 2 is reduced, and the degassing performance of the entire degassing system 1 is improved.

Specifically, among the plurality of degassing modules 2, one degassing module 2 is defined as an upstream degassing module 2 (upstream degassing module), and the degassing module 2 on the downstream side of the upstream degassing module is defined as a downstream degassing module 2 (downstream degassing module). For example, when the degassing module 2A is an upstream degassing module 2, any one of the degassing modules 2B, 2C, and 2D is the downstream degassing module 2. The degassing unit 3 is configured such that the pressure loss of the liquid from the supply port 6a of the connection supply pipe 6 to the discharge port 13a of the degassing module 2 on the downstream side is greater than the pressure loss of the liquid from the supply port 6a to the discharge port 13a of the degassing module 2 on the upstream side. In the present specification, the pressure loss refers to the pressure loss of the liquid flowing through the degassing system 1. In this case, the degassing unit 3 may be configured such that the pressure loss of the liquid from the opening 6b formed at the position corresponding to the downstream degassing module 2 to the discharge port 13a of the downstream degassing module 2 is greater than the pressure loss of the liquid from the opening 6b formed at the position corresponding to the upstream degassing module 2 to the discharge port 13a of the downstream degassing module 2.

Any two of the plurality of degassing modules 2 may satisfy the above-described relationship. For example, the pressure loss may be the same (actually the same) between the adjacent degassing modules 2 along the connection supply pipe 6. The same meaning of the above-described pressure loss between the degassing modules 2 adjacent along the connection supply pipe 6 also includes a case where the pressure loss differs by, for example, about 30% due to a manufacturing error or the like.

The pressure loss of the liquid from the supply port 6a to the discharge port 13a of each degassing module 2 can be obtained by measuring the pressure of the liquid at the supply port 6a and the pressure of the liquid at the discharge port 13a of each degassing module 2 by a pressure gauge or the like, and calculating the difference between them, for example.

As described above, in the degassing system 1 according to the present embodiment, the liquid is supplied in parallel to the hollow fiber membrane bundles 12 of the plurality of degassing modules 2 by the connection supply pipe 6 connecting the liquid supply paths 10 of the plurality of degassing modules 2 in series. However, the pressure loss of the liquid from the supply port 6a of the connection supply pipe 6 to the discharge port 13a of the degassing module 2 on the downstream side is larger than the pressure loss of the liquid from the supply port 6a of the connection supply pipe 6 to the discharge port 13a of the degassing module 2 on the upstream side. Therefore, this difference in pressure loss acts to cancel out the difference in flow velocity and pressure in the flow direction of the liquid. As a result, the deviation of the flow rate of the liquid between the upstream degassing module 2 and the downstream degassing module 2 is reduced, and therefore the degassing performance of the entire degassing system 1 can be improved.

Further, the pressure loss of the liquid from the opening 6b formed at the position corresponding to the downstream-side degassing module 2 to the discharge port 13a of the downstream-side degassing module 2 is set to be larger than the pressure loss of the liquid from the opening 6b formed at the position corresponding to the upstream-side degassing module 2 to the discharge port 13a of the upstream-side degassing module 2, so that the liquid is less likely to flow to the downstream-side degassing module 2 than to the upstream-side degassing module 2. This can improve the degassing performance of the entire degassing system 1.

Here, the pressure loss from the supply port 6a to the discharge port 13a of each degassing module 2 is, for example, the sum of [1] the pressure loss of the liquid in the connection supply pipe 6, [2] the pressure loss of the liquid at the opening 6b of the connection supply pipe 6, [3] the pressure loss of the liquid at the inner pipe opening 11a of the module inner pipe 11, [4] the pressure loss of the liquid at the hollow fiber membrane bundle 12, and [5] the pressure loss of the liquid at the discharge port 13a of the module container 13. Therefore, for example, by adjusting a part or all of them, the pressure loss from the supply port 6a to the discharge port 13a of the downstream-side degassing module 2 can be made larger than the pressure loss from the supply port 6a to the discharge port 13a of the upstream-side degassing module 2.

[1] Regarding the pressure loss of the liquid in the connection supply pipe 6, the connection supply pipe 6 is configured such that the pressure loss of the liquid at a position of the connection supply pipe 6 corresponding to the downstream-side degassing module 2 is larger than the pressure loss of the liquid at a position of the connection supply pipe 6 corresponding to the upstream-side degassing module 2.

By setting the pressure loss of the liquid at the position corresponding to the downstream-side degassing module 2 of the connection supply pipe 6 to be larger than the pressure loss of the liquid at the position corresponding to the upstream-side degassing module 2 of the connection supply pipe 6, the pressure loss of the liquid from the supply port 6a of the connection supply pipe 6 to the discharge port 13a of the downstream-side degassing module 2 can be set to be larger than the pressure loss of the liquid from the supply port 6a of the connection supply pipe 6 to the discharge port 13a of the upstream-side degassing module 2.

Specifically, for example, the inner diameter of the connection supply pipe 6 at the position corresponding to the downstream-side degassing module 2 may be smaller than the inner diameter of the connection supply pipe 6 at the position corresponding to the upstream-side degassing module 2. In this case, for example, as the connection supply pipe 6, a connection supply pipe whose inner diameter is tapered from the upstream side toward the downstream side may be used, or a connection supply pipe whose inner diameter is gradually tapered from the upstream side toward the downstream side may be used. With this arrangement, the pressure loss of the liquid at the position corresponding to the downstream-side degassing module 2 of the connection supply pipe 6 can be made larger than the pressure loss of the liquid at the position corresponding to the upstream-side degassing module 2 of the connection supply pipe 6.

[2] The pressure loss of the liquid at the opening 6b of the connection supply pipe 6 is configured such that the pressure loss of the liquid at the opening 6b formed at the position corresponding to the downstream-side degassing module 2 is larger than the pressure loss of the liquid at the opening 6b formed at the position corresponding to the upstream-side degassing module 2.

In this way, by setting the pressure loss of the liquid formed in the opening 6b corresponding to the downstream-side degassing module 2 to be larger than the pressure loss of the liquid formed in the opening 6b corresponding to the upstream-side degassing module 2, the pressure loss of the liquid from the supply port 6a of the connection supply pipe 6 to the discharge port 13a of the downstream-side degassing module 2 can be set to be larger than the pressure loss of the liquid from the supply port 6a of the connection supply pipe 6 to the discharge port 13a of the upstream-side degassing module 2.

Specifically, for example, the total area of the openings 6b formed at the position corresponding to the downstream-side degassing module 2 may be smaller than the total area of the openings 6b formed at the position corresponding to the upstream-side degassing module 2. For example, the number of openings 6b formed at a position corresponding to the downstream-side degassing module 2 may be smaller than the number of openings 6b formed at a position corresponding to the upstream-side degassing module 2. For example, the size of the opening 6b formed at the position corresponding to the downstream-side degassing module 2 may be smaller than the size of the opening 6b formed at the position corresponding to the upstream-side degassing module 2. With this arrangement, the pressure loss of the liquid formed in the opening 6b corresponding to the downstream-side degassing module 2 can be made larger than the pressure loss of the liquid formed in the opening 6b corresponding to the upstream-side degassing module 2.

[3] The pressure loss of the liquid at the inner tube opening 11a of the module inner tube 11 is configured such that the pressure loss of the liquid at the inner tube opening 11a of the downstream-side degassing module 2 is larger than the pressure loss at the inner tube opening 11a of the upstream-side degassing module 2.

In this way, by setting the pressure loss of the liquid at the inner tube opening 11a of the downstream-side degassing module 2 to be larger than the pressure loss of the liquid at the inner tube opening 11a of the upstream-side degassing module 2, the pressure loss of the liquid from the supply port 6a of the connection supply pipe 6 to the discharge port 13a of the downstream-side degassing module 2 can be set to be larger than the pressure loss of the liquid from the supply port 6a of the connection supply pipe 6 to the discharge port 13a of the upstream-side degassing module 2.

Specifically, for example, the total area of the inner tube openings 11a of the downstream-side degassing module 2 may be smaller than the total area of the inner tube openings 11a of the upstream-side degassing module 2. For example, the number of inner tube openings 11a of the downstream-side degassing module 2 may be smaller than the number of inner tube openings 11a of the upstream-side degassing module 2. For example, the size of the inner tube opening 11a of the downstream degassing module 2 may be smaller than the size of the inner tube opening 11a of the upstream degassing module 2. With this arrangement, the pressure loss of the liquid at the inner tube opening 11a of the downstream-side degassing module 2 can be made larger than the pressure loss of the liquid at the inner tube opening 11a of the upstream-side degassing module 2.

[4] The pressure loss of the liquid in the hollow fiber membrane bundle 12 is configured such that the pressure loss in the hollow fiber membrane bundle 12 of the downstream-side degassing module 2 is higher than the pressure loss in the hollow fiber membrane bundle 12 of the upstream-side degassing module 2.

By setting the pressure loss of the liquid at the hollow fiber membrane bundle 12 of the downstream-side degassing module 2 to be larger than the pressure loss of the liquid at the hollow fiber membrane bundle 12 of the upstream-side degassing module 2, the pressure loss of the liquid from the supply port 6a of the connection supply pipe 6 to the discharge port 13a of the downstream-side degassing module 2 can be set to be larger than the pressure loss of the liquid from the supply port 6a of the connection supply pipe 6 to the discharge port 13a of the upstream-side degassing module 2.

Specifically, for example, the density of the plurality of hollow fiber membranes 14 in the downstream-side degassing module 2 may be higher than the density of the plurality of hollow fiber membranes 14 in the upstream-side degassing module 2. By increasing the density of the plurality of hollow fiber membranes 14, the gaps between the plurality of hollow fiber membranes 14 are reduced, and the passing resistance of the liquid with respect to the hollow fiber membrane bundle 12 becomes large. Therefore, the pressure loss of the liquid at the hollow fiber membrane bundle 12 of the degassing module 2 on the downstream side is larger than the pressure loss of the liquid at the hollow fiber membrane bundle 12 of the degassing module 2 on the upstream side.

For example, the thickness of the hollow fiber membrane bundle 12 in the downstream degassing module 2 may be larger than the thickness of the hollow fiber membrane bundle 12 in the upstream degassing module 2. By increasing the thickness of the hollow fiber membrane bundle 12, the passing resistance of the liquid with respect to the hollow fiber membrane bundle 12 becomes large. Therefore, the pressure loss of the liquid at the hollow fiber membrane bundle 12 of the degassing module 2 on the downstream side is larger than the pressure loss of the liquid at the hollow fiber membrane bundle 12 of the degassing module 2 on the upstream side.

In the case where the hollow fiber membrane bundle 12 is formed by winding a woven fabric, which is woven by a plurality of hollow fiber membranes 14 as weft yarns, around the module inner tube 11 (the periphery of the liquid supply path 10) by using warp yarns, for example, the winding pressure of the woven fabric in the downstream-side degassing module 2 may be higher than the winding pressure of the woven fabric in the upstream-side degassing module 2. In this case, the fabric may be wound around the module inner tube 11 (around the liquid supply channel 10) so that the plurality of hollow fiber membranes 14 extend in the axial direction of the module inner tube 11 (liquid supply channel 10). By increasing the winding pressure of the winding object, the gaps between the plurality of hollow fiber membranes 14 become narrow, and the passing resistance of the liquid with respect to the hollow fiber membrane bundle 12 becomes large. Therefore, the pressure loss of the liquid at the hollow fiber membrane bundle 12 of the degassing module 2 on the downstream side is larger than the pressure loss of the liquid at the hollow fiber membrane bundle 12 of the degassing module 2 on the upstream side.

Similarly, when the hollow fiber membrane bundle 12 is a woven fabric in which a plurality of hollow fiber membranes 14 as weft yarns are woven by warp yarns, the plurality of hollow fiber membranes 14 are wound around the module inner tube 11 (around the liquid supply path 10) so as to extend in the axial direction of the module inner tube 11 (the liquid supply path 10), for example, the pitch of the warp yarns at the downstream-side degassing module 2 may be longer than the pitch of the warp yarns at the upstream-side degassing module 2. When the fabric is wound around the module inner tube 11, the hollow fiber membranes 14 on the outer circumferential side are intended to enter between the adjacent hollow fiber membranes 14 on the inner circumferential side. In this case, when the pitch of the warp yarns in the degassing module 2 is short, the interval supported by the warp yarns on the inner circumferential side becomes narrow in the hollow fiber membranes 14 on the outer circumferential side, and therefore, the hollow fiber membranes 14 adjacent to each other on the inner circumferential side are less likely to enter between them. As a result, the density of the hollow fiber membranes 14 is reduced. On the other hand, when the pitch of the warp yarns in the degassing module 2 is long, the outer peripheral hollow fiber membranes 14 are easily inserted between the adjacent inner peripheral hollow fiber membranes 14 because the interval supported by the inner peripheral warp yarns is long. As a result, the density of the hollow fiber membranes 14 becomes high. Therefore, the pressure loss of the liquid in the hollow fiber membrane bundle 12 of the degassing module 2 on the downstream side is larger than the pressure loss of the liquid in the hollow fiber membrane bundle 12 of the degassing module 2 on the upstream side.

For example, the outer diameter of the hollow fiber membranes 14 in the downstream-side degassing module 2 may be larger than the outer diameter of the hollow fiber membranes 14 in the upstream-side degassing module 2. For example, in the case where the number of hollow fiber membranes 14 is the same, by enlarging the outer diameter of the hollow fiber membranes 14, the gap between the hollow fiber membranes 14 becomes narrow, and the passing resistance of the liquid with respect to the hollow fiber membrane bundle 12 becomes large. Therefore, the pressure loss of the liquid in the hollow fiber membrane bundle 12 of the degassing module 2 on the downstream side is larger than the pressure loss of the liquid in the hollow fiber membrane bundle 12 of the degassing module 2 on the upstream side.

For example, the hollow fiber membranes 14 in the downstream-side degassing module 2 may have higher hydrophilicity than the hollow fiber membranes 14 in the upstream-side degassing module 2. When the hydrophilicity of the hollow fiber membranes 14 is high, the contact resistance of the liquid with respect to the hollow fiber membranes 14 becomes large. Therefore, the pressure loss of the liquid in the hollow fiber membrane bundle 12 of the degassing module 2 on the downstream side is larger than the pressure loss of the liquid in the hollow fiber membrane bundle 12 of the degassing module 2 on the upstream side.

[5] The pressure loss of the liquid at the discharge port 13a of the module container 13 is configured such that the pressure loss of the liquid at the discharge port 13a of the downstream-side degassing module 2 is larger than the pressure loss of the liquid at the discharge port 13a of the upstream-side degassing module 2.

By setting the pressure loss of the liquid at the discharge port 13a of the downstream-side degassing module 2 to be larger than the pressure loss of the liquid at the discharge port 13a of the upstream-side degassing module 2, the pressure loss of the liquid from the supply port 6a of the connection supply pipe 6 to the discharge port 13a of the downstream-side degassing module 2 can be set to be larger than the pressure loss of the liquid from the supply port 6a of the connection supply pipe 6 to the discharge port 13a of the upstream-side degassing module 2.

Specifically, for example, the total area of the discharge ports 13a of the downstream-side degassing module 2 may be smaller than the total area of the discharge ports 13a of the upstream-side degassing module 2. For example, the number of the discharge ports 13a of the downstream degassing module 2 may be smaller than the number of the discharge ports 13a of the upstream degassing module 2. Further, the size of the discharge port 13a of the downstream degassing module 2 may be smaller than the size of the discharge port 13a of the upstream degassing module 2. With this arrangement, the pressure loss of the liquid at the discharge port 13a of the downstream degassing module 2 can be made larger than the pressure loss of the liquid at the discharge port 13a of the upstream degassing module 2.

[ method for producing deaeration System ]

Next, a method for manufacturing the degassing system 1 will be described.

First, a supply pipe 6 and a plurality of degassing modules 2 are connected to each other. Next, the connection supply pipe 6 is inserted into the liquid supply path 10 of the plurality of degassing modules 2. Then, the liquid supply paths 10 of the plurality of degassing modules 2 are connected in series by the connection supply pipe 6. Further, the plurality of openings 6b connecting the supply pipes 6 are disposed at positions corresponding to the plurality of degassing modules 2 so that the liquid is supplied in parallel to the hollow fiber membrane bundles 12 of the plurality of degassing modules 2.

Here, among the plurality of degassing modules 2, one of the degassing modules 2 is defined as an upstream-side degassing module 2 (upstream-side degassing module), and one of the degassing modules 2 on the downstream side of the upstream-side degassing module is defined as a downstream-side degassing module 2 (downstream-side degassing module). The pressure loss of the liquid from the supply port 6a of the connection supply pipe 6 to the discharge port 13a of the degassing module 2 on the downstream side is set to be larger than the pressure loss of the liquid from the supply port 6a to the discharge port 13a of the degassing module 2 on the upstream side. Such setting of the pressure loss of the liquid can be performed by the various methods described above.

The embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments. For example, although the configuration of the degassing module is specifically described in the above embodiment, various types of degassing modules can be used as the degassing module. In the above embodiment, the description has been given of the structure in which each deaeration module has a module inner pipe, but such a module inner pipe may not be provided. In this case, for example, the hollow fiber membrane bundle (woven fabric) of each degassing module is directly wound around the connection supply pipe.

The method of using and the method of using the degassing system of the present invention are not particularly limited, and the degassing system can be used in the technical field of production of natural resources such as the spray drilling method, the In Situ Leaching (ISL), and the water-tapping method. Specifically, it can be used in the following production method of natural resources. Namely, the method for producing the natural resource comprises: a degassing step of supplying a liquid from the connection supply pipe to the liquid supply paths of the plurality of degassing modules and degassing the liquid by reducing the pressure inside the plurality of hollow fiber membranes of each of the plurality of degassing modules in the degassing system according to the present invention; and a pressure-feeding step of feeding the liquid degassed in the degassing step into a natural resource exploitation site. Examples of the natural resources include metal minerals such as copper and uranium, and fuel minerals such as crude oil, natural gas, shale oil, and shale gas. Examples of the liquid include water. In the case where the natural resource is a fuel mineral, examples of the liquid include seawater, associated water, and a fracturing fluid. The associated water is water produced in the production of natural resources. The degassing unit used in the present invention can be manufactured by connecting a plurality of degassing modules in advance and then transferring the degassing module to a place of use, or can be manufactured by connecting degassing modules that are individually conveyed at a place of use of the degassing system of the present invention. In the case where any of the degassing modules is defective, only the corresponding degassing module may be replaced, and the handling property and the maintenance property in use when the module is transferred during manufacturing are excellent. Therefore, for example, it is also suitable for use in a natural resource exploitation site.

Description of reference numerals

1. A degassing system; 2. 2A, 2B, 2C, 2D, a degassing module (upstream side degassing module, downstream side degassing module); 3. a degassing unit; 4. a housing; 4a, an inlet; 4b, an outlet; 5. a suction tube; 6. connecting the supply pipe; 6a, a supply port; 6b, opening; 7. a housing sealing portion; 8. a degassing unit support part; 10. a liquid supply path; 11. a module inner tube; 11a, an inner pipe opening; 12. a hollow fiber membrane bundle; 12a, an end portion; 13. a modular container; 13a, a discharge port; 14. a hollow fiber membrane; 15. a sealing part; A. a degassing zone; B. an upstream side region; C. a downstream side region.