KR20210027007A - Method for producing three-dimensional crystalline porous structure and filter medium produced by the method - Google Patents

Abstract

The present disclosure relates to a filter medium and, more specifically, to a method for manufacturing a three-dimensional crystalline porous structure through the conversion of a 3D model of a structure into a Voronoi structure and fused deposition modeling, and a biological filter medium manufactured by the method. The present disclosure is presented as a method for manufacturing a three-dimensional crystalline porous structure, comprising: a modeling step of forming a 3D model of a structure; a conversion step of converting the 3D model formed in the modeling step into a Voronoi structure; and an output step of outputting the Voronoi structure (Voronoi Diagram or Voronoi Tessellation) converted in the conversion step using a fused deposition modeling (FDM) 3D printer.

Description

A method of manufacturing a three-dimensional crystalline porous structure, and a filter medium manufactured by the method {METHOD FOR PRODUCING THREE-DIMENSIONAL CRYSTALLINE POROUS STRUCTURE AND FILTER MEDIUM PRODUCED BY THE METHOD}

The present disclosure relates to a filter medium, and more particularly, to a method for manufacturing a three-dimensional crystalline porous structure through transformation of a 3D model of the structure into a Voronoi structure and melt extrusion lamination modeling, and a biological filter material manufactured by the method. will be.

Unless otherwise indicated in the specification, the contents described in this identification item are not prior art to the claims of this application, and description in this identification item is not admitted to be prior art.

As a prior art, research on manufacturing porous structures such as medical scaffolds by using a Fused Deposition Modeling (FDM) 3D printer in the past has been made. Most of the existing porous structure fabrication is a method of forming amorphous pores by using additives such as a foaming agent in the filament. Porous manufacturing method by additives can easily form pores, but because it is a manufacturing method in which arbitrary pores are formed by additives. There is a problem in that it is difficult to adjust the size and number of pores.

In addition, conventional methods of manufacturing biological filter media include crushing ceramics or fiber-reinforced plastics into a specific particle size and immersing them in a mixed solution mixed with defects and other additives, and stone powder, activated carbon, filter yarn, etc. in pulverized waste vinyl. There is a method of preparing by extruding and cooling the subsidiary material of, but there is a problem in that the pores are not produced in an optimal size for culturing bacteria when this method is used.

1. Korean Patent Registration No. 10-1471435 (announced on Dec. 11, 2014) 2. Korean Patent Application Publication No. 10-2019-0067541 (published on June 17, 2019) 3. Republic of Korea Patent Publication 10-2018-0040555 (published on April 20, 2018) 4. Korean patent registration 10-1869106 (2018.06.19 announcement) 5. Korean Patent Publication 10-2019-0034123 (published on April 1, 2019)

Accordingly, the object of the present invention is that the prior art is unable to precisely adjust the size and number of pores.The present invention is a filter medium having optimal pores for optimal bacterial culture through the arrangement of the optimal pore size using a Voronoi structure, and the filter medium Its purpose is to provide a method of manufacturing.

In addition, it is not limited to the above-described technical problems, and it is obvious that another technical problem may be derived from the following description.

The present disclosure is a modeling step of forming a 3D model of a structure, a transformation step of converting the 3D model formed in the modeling step to a Voronoi structure, and a Voronoi Diagram or Voronoi Tessellation transformed in the transformation step by melt extrusion. Fused Deposition Modeling (FDM) It is presented as a method of manufacturing a 3D crystalline porous structure including an output step of printing using a 3D printer.

According to an embodiment of the present disclosure, there is provided a biological filter medium that overcomes the limitations of the existing filter medium by forming an optimal bacterial culture condition with optimal pores.

The effects of the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

1 is a flow chart for a method of manufacturing a three-dimensional crystalline porous structure according to an embodiment of the disclosed content.
2 is a flow chart for a conversion step in a method for manufacturing a three-dimensional crystalline porous structure according to an embodiment of the disclosed content.
3 is a plan view of a generator forming step according to an embodiment of the disclosed subject matter.
4 is a plan view of a step of forming a mesh structure according to an embodiment of the present disclosure.
5 is a plan view of a pore forming step according to an embodiment of the present disclosure.
6 is a graph of the experimental results of the present disclosure.

Hereinafter, with reference to the accompanying drawings, a method of manufacturing a three-dimensional crystalline porous structure according to a preferred embodiment and a configuration, operation, and effect of the filter medium manufactured by the method will be described. For reference, in the drawings below, each component is omitted or schematically illustrated for convenience and clarity, and the size of each component does not reflect the actual size. In addition, the same reference numerals refer to the same elements throughout the specification, and reference numerals for the same elements in individual drawings will be omitted.

1 is a flowchart illustrating a method of manufacturing a three-dimensional crystalline porous structure according to an embodiment of the disclosure.

As shown in FIG. 1, the method of manufacturing a three-dimensional crystalline porous structure includes a modeling step (S100) of forming a 3D model of the structure, and a conversion step (S200) of converting the 3D model formed in the modeling step (S100) into a Voronoi structure. , The Voronoi Diagram or Voronoi Tessellation transformed in the transformation step S200 is output using a fused deposition modeling (FDM) 3D printer (S300).

The modeling step (S100) is a step of forming a 3D model of the structure (S100) is a step of forming a 3D model of the structure having a desired shape. In the present invention, since the biological filter medium is formed by forming internal crystalline pores regardless of the shape, the shape and size of the model are irrelevant when forming a 3D model. Since the shape and size of the model are irrelevant, it can be combined with a block-type filter material that can be customized. That is, the block-type filter medium has a structure that can be combined by direct piling and insulting. This allows consumers to express their tastes as sculptures while considering the ecological characteristics of marine life in the tank.

The conversion step (S200) is a step of converting the 3D model formed in the modeling step (S100) into a three-dimensional crystalline porous structure by forming optimal pores using the Voronoi structure. In the conversion step (S200), the 3D model is divided into layers having a certain thickness to form pores, and the three layers are grouped to form a layer group (S210), and the center of gravity of each layer group is derived. The generator forming step (S230) of generating equally spaced points with the center of gravity as the origin, the mesh structure forming step (S250) of forming a triangle bearing the center of gravity and forming a triangular mesh structure connecting adjacent points (S250), a triangular mesh It includes a pore forming step (S270) of forming pores by forming a Voronoi structure around the forming points.

The algorithm of the conversion step S200 may be expressed as follows.

= sqrt(2Rd -

)로 하는 원점이 무게중심인 원이 있는 레이어 그룹의 나머지 두 층과 함께 포개어, 7μm ~ 50μm의 기공을 형성한다.
For other layers of a layer group
Form circle with

= sqrt(2Rd -

) and its center is MCP.
End For
EndInput: Slice of 3D Model (SM), Mass Center Point of Layer (MCP),
Distance L (L), Radius (R), Nozzle diameter (d)
Output: Number of Porous
Begin
// Forming a layer group to form pores
Form groups of layer which 3 layer in 1 set
// Create equally spaced points based on the center of gravity on one layer of the layer group
For each SMi
Find out PMC of each layer plane and scatter points with same distance (L) and
angle (60 degree)
End For

// A triangle containing the origin (center of gravity of the face) and a triangular mesh structure connecting adjacent points.
Form Initial Triangle (IT) with a group of 3 points which can contain MCP in
its center
Form triangles with adjacent points of same distance (L) with IT

// Create a circle centered around the points that form a triangular mesh
For each vertex of triangle
Compute R (Radius) with L (Distance) and d (Nozzle diameter)
Create circles (radius = R) with each point. And each triangle contains a circle
with R
End For

// The layer has a radius

= sqrt(2Rd-

The original point denoted by) overlaps with the other two layers of the layer group with a circle whose center of gravity is to form pores of 7 μm to 50 μm.
For other layers of a layer group
Form circle with

= sqrt(2Rd-

) and its center is MCP.
End For
End

Finally, the output step (S300) is a step of converting the 3D model in which the pores converted in the conversion step (S200) are formed into a G code and outputting it.

2 is a flow chart for a conversion step in a method for manufacturing a 3D crystalline porous structure according to an embodiment of the disclosed content, FIG. 3 is a plan view of a generator forming step (S230) according to an embodiment of the disclosed content, and FIG. 4 is a view A plan view of a mesh structure forming step S250 according to an embodiment of the disclosure, and FIG. 5 is a plan view illustrating a pore forming step S270 according to an embodiment of the present disclosure.

2, 3, 4, and 5, the conversion step (S200) is a layer group formation step of dividing the 3D model into layers having a certain thickness and grouping the three layers into groups to form a layer group (S210). ), generator formation step (S230) of deriving the center of gravity of the layer group and generating equally spaced points with the center of gravity as the origin, forming a triangle bearing the center of gravity, and forming a triangular mesh structure connecting adjacent points It characterized in that it comprises a forming step (S250), a pore forming step (S270) of forming pores by forming a Voronoi structure around points forming a triangular mesh.

The layer group forming step S210 is a step of dividing the 3D model into layers having regular intervals and forming the three layers into one group. The 3D model formed in the modeling step (S100) goes through a process of dividing all surfaces into triangles of small size through a tessellation method. Through the program, the contour data of the shape model can be extracted, and the lines cross each triangle constituting the shape model. At this time, the thickness of the layer [slice thickness] is the same as the thickness of the filament [filament thickness]. Also, the height [slicing plane Z_i] from the bottom of the nth layer becomes Z_min + [slice thickness]. If the height is greater than the minimum value of Z and less than the maximum value of Z, the triangle interferes with the adjacent layer. In this way, if you have the following specifications, a total of 457 layers can be obtained when the slice thickness is 0.1.

X_max X_min Y_max Y_min Z_max Z_min 76 0.05 21 0.05 45 0.05

At this time, the [slice thickness] is the same as the thickness of the nozzle of the 3D printer to be used in the output step (S300).

The generator forming step (S230) is a step of deriving the center of gravity of each layer group and generating equally spaced points based on the center of gravity. The faces of each layer divided in the layer group formation step have the following centers of gravity.

Center of gravity G(x, y, z) =

The generator of the layer is constructed with the center of gravity as the origin. The spacing between each point and the angle between the points are as follows.

The mesh structure forming step S250 is a step of forming a triangle having a center of gravity and forming a triangular mesh structure connecting adjacent points. Each layer forms a triangular mesh having the same area based on the generator generated in the planar generator forming step S230. Specifically, a triangular mesh structure is formed by connecting the points of the shortest distance based on the center of gravity of the generator formed in the above step.

The pore forming step (S270) is a step of forming pores by forming a Voronoi structure around points forming a triangular mesh. A Voronoi diagram is formed based on the three points of each triangular mesh formed in the mesh structure forming step S250 and the center of gravity of the mesh. Create an inscribed circle inside each diagram. When the radius of the inscribed circle to be formed is R, the distance L of each point and the radius of the inscribed circle are as follows.

를 따르고, 중심 레이어 상하로 존재하는 레이어는 반지름이

를 따른다. 이 중심 레이어와 상하레이어가 포개어져 7μm ~ 50μm의 기공을 형성한다.The layer existing in the middle based on each layer group formed in the layer group forming step (S210) has a radius

And the layer that exists above and below the center layer has a radius

Follows. This central layer and the upper and lower layers are superimposed to form pores of 7 μm to 50 μm.

6 shows a graph of the experimental results of the present disclosure.

As shown in FIG. 6, it can be seen that the ammonia concentration of the filter medium manufactured by the method of manufacturing a three-dimensional crystalline porous structure according to the present disclosure was significantly lowered compared to the initial ammonia concentration.

The Example and the control group showed the same ppm on Day 1, Day 7 and Day 15, but by Day 29, the Example showed 0,5 ppm and the control group 0.6 ppm, and the obvious effect of the present disclosure can be confirmed.

The experiment was carried out with the following comparison group and experimental group.

As a result of the experiment, there was no significant change in concentration until the first 15 days. However, in the 7th measurement on the 29th day, it was confirmed that the ammonia concentration was significantly lower than that of the Reference (initial ammonia concentration). That is, through optimization and diversification of the pore size, it was confirmed that the filtration ability of the prototype was superior to that of the comparative group. The experimental results are summarized in a table as follows.

Although preferred embodiments of the present invention have been described with reference to the accompanying drawings, the embodiments described in this specification and the configurations shown in the drawings are only the most preferred embodiments of the present invention, and represent all the technical ideas of the present invention. Since this is not, it should be understood that there may be various equivalents and modifications that may be substituted for them at the time of application. Therefore, the embodiments described above are to be understood as illustrative and non-limiting in all respects, and the scope of the present invention is indicated by the claims to be described later rather than the detailed description, and the meaning and scope of the claims and the All changes or modifications derived from the equivalent concept should be construed as being included in the scope of the present invention.

S 100; Modeling stage
S 200; Conversion Step
S 300; Output stage
S 210; Layer group formation stage
S 230; Generator formation stage
S 250; Mesh structure formation stage
S 270; Pore formation stage

Claims (4)

A modeling step of forming a 3D model of the structure;
A conversion step of converting the 3D model formed in the modeling step into a Voronoi structure;
An output step of outputting the Voronoi structure (Voronoi Diagram or Voronoi Tessellation) transformed in the conversion step using a fused deposition modeling (FDM) 3D printer.
The method according to claim 1,
The conversion step is
A layer group forming step of dividing the 3D model into layers having a predetermined thickness and grouping the three layers into a group to form a layer group;
A generator forming step of deriving the center of gravity of the layer group and generating equally spaced points based on the center of gravity;
A mesh structure forming step of forming a triangle having the center of gravity and forming a triangular mesh structure connecting adjacent points;
A method for manufacturing a three-dimensional crystalline porous structure comprising: forming pores by forming a Voronoi structure around the points forming the triangular mesh.
The method according to claim 2,
The generator forming step is a method for manufacturing a three-dimensional crystalline porous structure, characterized in that the layer thickness coincides with the thickness of the filament.
The method according to claim 2 or 3,
The filter medium manufactured by the method of manufacturing a three-dimensional crystalline porous structure has pores of 7 μm to 50 μm.

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