Excrement treatment material and method for producing the same

Abstract

To provide an excrement treatment material suitable for low-cost production, while containing two types of granules with different properties, and a method for producing the same.SOLUTION: An excrement treatment material 1 includes granules 10 and granules 20. The granules 10 have water-repellent nature while granules 20 have water-absorbent nature. The granules 20 are composed of the same material composition as the granules 10.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an excrement treating material and a method for producing the same. [Background technology]

[0002] An example of a conventional excrement treatment material is that described in Patent Document 1. The excrement treatment material described in this document is an animal excrement treatment material for use in animal litter boxes, and is made of a plurality of granules. The plurality of granules includes two types of granules with different properties. That is, granules having water repellency and granules having water absorbency are mixed together. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2006-55098 A Summary of the Invention [Problem to be solved by the invention]

[0004] The water-repellent granular material in the above-mentioned excrement treatment material is obtained by applying a water-repellent treatment to the surface of a water-absorbent base material. Therefore, the water-repellent granular material and the water-absorbent granular material are made of materials with different compositions. Therefore, a material for making the water-repellent granular material must be prepared separately from the material for making the water-absorbent granular material. This causes an increase in the manufacturing cost of the excrement treatment material.

[0005] The present invention has been made in consideration of the above-mentioned problems, and aims to provide an excrement treatment material that is suitable for low-cost production despite containing two types of granular material with different properties, and a method for producing the same. [Means for solving the problem]

[0006] The excrement treatment material according to the present invention is characterized by comprising a first granular body having hydrophobic properties and a second granular body made of a material having the same composition as the first granular body and having water-absorbent properties.

[0007] This excrement treatment material is provided with hydrophobic granular material (first granular material) and water-absorbent granular material (second granular material). The first and second granular material are made of materials with the same composition. Therefore, it is not necessary to prepare materials for the first and second granular material separately. Sharing the material of the first and second granular material in this way contributes to reducing the manufacturing cost of the excrement treatment material.

[0008] In addition, the manufacturing method for excrement treatment material according to the present invention is characterized by including a first granular body formation step of forming a first granular body having hydrophobic properties, and a second granular body formation step of forming a second granular body having water absorbency and made of a material having the same composition as the first granular body.

[0009] In this manufacturing method, hydrophobic granular materials (first granular materials) and water-absorbent granular materials (second granular materials) are formed. The first and second granular materials are made of materials with the same composition. Therefore, it is not necessary to prepare materials for the first and second granular materials separately. Sharing the material of the first and second granular materials in this way contributes to reducing the manufacturing costs of the excrement treatment material. Effect of the Invention

[0010] According to the present invention, an excrement treating material that is suitable for low-cost production despite containing two types of granular material with different properties, and a production method thereof are realized. [Brief description of the drawings]

[0011] [Figure 1] 1 is a schematic diagram showing an embodiment of an excrement treating material according to the present invention. [Diagram 2] FIG. 2 is a plan view showing the extrusion granulator 30. [Diagram 3]FIG. 2 is a bottom view showing the extrusion granulator 30. [Figure 4] FIG. 4 is an end view taken along line IV-IV in FIG. [Diagram 5] FIG. 2 is a diagram for explaining the process of forming granules 10 and 20 using an extrusion granulator 30. [Figure 6] FIG. 2 is a diagram for explaining the process of forming granules 10 and 20 using an extrusion granulator 30. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the description of the drawings, the same elements are given the same reference numerals and duplicated description will be omitted.

[0013] FIG. 1 is a schematic diagram showing one embodiment of an excrement treatment material according to the present invention. The excrement treatment material 1 is an excrement treatment material used to treat excrement (mainly urine). The excrement treatment material 1 may be an animal excrement treatment material used to treat excrement from animals such as cats and dogs, or a human excrement treatment material used to treat human excrement. The excrement treatment material 1 is made of a plurality of granular bodies for treating excrement. The excrement treatment material 1 is used, for example, in a state where the plurality of granular bodies are laid in a box-shaped toilet. The excrement treatment material 1 includes granular bodies 10 (first granular bodies) and granular bodies 20 (second granular bodies). That is, the plurality of granular bodies constituting the excrement treatment material 1 include granular bodies 10 and granular bodies 20.

[0014] The granular material 10 has hydrophobicity (water repellency). That is, the granular material 10 has a property of not absorbing any liquid such as urine, or of absorbing very little if any. For the granular material 10 to be said to be hydrophobic, it is necessary that the liquid passage rate measured by the following test is greater than 60%. First, 50 g of the granular material 10 (sample) is placed in a sieve with an inner diameter of 10 cm and an opening of 1 mm. An empty beaker is placed under the sieve. Then, 30 ml of water is dripped onto the sample over 10 seconds using a syringe (Terumo 60 ml syringe) with an outer cylinder inner diameter of 3 cm and a tip inner diameter of 4 mm. After leaving it for 1 minute, the amount of water in the beaker is measured. The ratio of the measured amount of water to the amount of dripped water (30 ml) is taken as the liquid passage rate. That is, if the amount of water in the beaker is greater than 18 ml, the liquid passage rate is greater than 60%, and therefore the granular material 10 can be said to be hydrophobic.

[0015] The granular material 20 has water absorption properties. In other words, the granular material 20 absorbs and retains liquids such as urine inside. For the granular material 20 to be said to have water absorption properties, the liquid passage rate measured by the above-mentioned test must be 60% or less. The liquid passage rate of the granular material 20 is preferably 70% or more, and more preferably 80% or more. The liquid passage rate of the granular material 20 is preferably 50% or less, and more preferably 40% or less.

[0016] A plurality of granular bodies 10 and a plurality of granular bodies 20 are provided. In the excrement treatment material 1, these granular bodies 10, 20 are mixed. The number of granular bodies 20 is preferably 30% or more and 70% or less of the total number of granular bodies 10 and 20, and more preferably 40% or more and 60% or less. The particle size of granular body 10 is equal to the particle size of granular body 20. Here, the particle size is defined as the diameter of the smallest sphere that can contain the granular body. The particle size of each of granular bodies 10, 20 is, for example, 5 mm or more and 30 mm or less.

[0017] Each granular body 10 has a granular shape. Examples of such granular shapes include a sphere, a cylinder, and an ellipsoid. Each granular body 10 is a granulated material whose surface is not coated. That is, each granular body 10 is not provided with a coating layer (a layer that covers a part or the entire surface of the granulated material). Therefore, the surface of the granulated material constituting the granular body 10 is not subjected to a hydrophobic treatment (water-repellent treatment). Each granular body 10 is preferably made mainly of an organic material. Here, the main material of the granular body 10 refers to the material that constitutes the granular body 10 and has the largest weight ratio in the granular body 10. Examples of such organic materials include paper, plants, plastics, and organic sludge. Each granular body 10 may be made of only organic materials, or may be made of organic and inorganic materials.

[0018] Papers refer to materials mainly composed of pulp. Examples of papers that can be used include ordinary paper (paper powder), fluff pulp, paper derived from PVC wallpaper (paper generated during the manufacture or classification of PVC wallpaper), paper derived from gypsum board (paper generated during the manufacture or classification of gypsum board), and paper derived from sanitary products (paper generated during the manufacture or classification of sanitary products containing paper). Examples of sanitary products containing paper include disposable diapers, sanitary napkins, urine pads, and sanitary paper (tissue paper, toilet paper, paper towels, etc.). Examples of plants that can be used include wood powder, sawdust, and plant residues (tea leaves, soybean lees, etc.). Examples of plastics that can be used include ordinary plastics, plastics derived from PVC wallpaper (plastics generated during the manufacture or classification of PVC wallpaper), and plastics derived from sanitary products (plastics generated during the manufacture or classification of sanitary products containing plastic). Examples of sanitary products containing plastic include disposable diapers, sanitary napkins, urine pads, and sanitary masks. Examples of organic sludges that can be used include paper sludge and pulp sludge. In this embodiment, each granular body 10 contains plastic. Plastic may or may not be the main material of the granular body 10.

[0019] Each granular body 20 is granular. Each granular body 20 is a granulated material whose surface is not coated. Each granular body 20 is preferably made mainly of an organic material. Here, the main material of the granular body 20 refers to the material that constitutes the granular body 20 and that accounts for the largest weight ratio of the granular body 20. Each granular body 20 may be made of only an organic material, or may be made of an organic material and an inorganic material. In this embodiment, each granular body 20 contains plastic. The granular body 20 is made of a material having the same composition as the granular body 10. That is, the type and ratio of the material constituting the granular body 20 are equal to the type and ratio of the material constituting the granular body 10. If the hydrophobic treatment (water-repellent treatment) is applied only to the surface of the granular body 10 among the granular body 10 and the granular body 20, the material used for the hydrophobic treatment is also included in the "material constituting the granular body 10", so it cannot be said that the granular body 20 is made of a material having the same composition as the granular body 10.

[0020] The apparent density of the granular body 10 is preferably larger than the apparent density of the granular body 20. The porosity of the granular body 10 is preferably smaller than the porosity of the granular body 20. Here, the porosity is defined as the volume ratio of the voids present inside each granular body to the entire granular body. When the true density of each granular body is Dt and the apparent density is Da, the porosity is expressed as 1-(Da / Dt). In addition, the average particle size of the plastic contained in the granular body 10 is preferably larger than the average particle size of the plastic contained in the granular body 20. Here, the average particle size refers to the minimum mesh size through which 50% or more by weight of the particles can pass when a plastic, which is an aggregate of a large number of particles (plastic powder or plastic pieces), is sieved.

[0021] Next, an example of a method for producing the excrement treating material 1 will be described as an embodiment of the method for producing the excrement treating material according to the present invention. This manufacturing method includes a first granular material forming step and a second granular material forming step.

[0022] The first granular body forming step is a step of forming the granular body 10. In this step, a granulating device is used to granulate the first granulated material (material constituting the granular body 10) to form a plurality of granulated products that will become the granular body 10. As the granulating device, for example, an extrusion granulator can be used. Prior to granulation, the first granulated material is subjected to pre-treatment such as pulverization, kneading, and addition of water as necessary. After granulation, post-treatment such as sieving (sizing) and drying is performed as necessary. As a result, a plurality of granular bodies 10 are obtained.

[0023] The second granular body forming step is a step of forming the granular body 20. In this step, a granulating device is used to granulate the second granulated material (material constituting the granular body 20) to form a plurality of granulated products that will become the granular body 20. The composition of the second granulated material is equal to the composition of the first granulated material. Prior to granulation, the second granulated material is subjected to pre-treatment such as pulverization, kneading, and addition of water as necessary. After granulation, post-treatment such as sieving (sizing) and drying is performed as necessary. As a result, a plurality of granular bodies 20 are obtained.

[0024] Thereafter, the granules 10 formed in the first granule formation step and the granules 20 formed in the second granule formation step are mixed. At this time, it is preferable to mix the granules 10 and the granules 20 so that the number of the granules 20 is 30% or more and 70% or less of the total number of the granules 10 and the granules 20. It is more preferable to mix the granules 10 and the granules 20 so that the number of the granules 20 is 40% or more and 60% or less of the total number of the granules 10 and the granules 20. As a result of the above, an excrement treatment material 1 in which the granules 10 and the granules 20 are mixed is obtained.

[0025] The order in which the first and second granular body forming steps are performed is arbitrary. That is, both steps may be performed simultaneously in parallel (using different devices), or one step may be performed before the other step. Alternatively, the first and second granular body forming steps may be performed simultaneously using the same device. That is, the first and second granular body forming steps may be performed as one step. In that case, the first and second granular body forming steps may be performed, for example, using an extrusion granulator 30 shown below.

[0026] 2 and 3 are respectively a plan view and a bottom view of the extrusion granulator 30. FIG. 4 is an end view taken along line IV-IV in FIG. 2. The extrusion granulator 30 has a die 32, a roller 34, and a cutter 36. The die 32 is circular in plan view. The die 32 has a uniform thickness. The die 32 is provided with a plurality of through holes 33 for passing the granulation materials (first and second granulation materials). In the following description, the term "a plurality of through holes 33" refers to all the through holes 33 provided in the die 32 unless otherwise specified. The plurality of through holes 33 have equal lengths. The plurality of through holes 33 are scattered over substantially the entire surface of the die 32. The shape of the cross section of each through hole 33 (a cross section perpendicular to the thickness direction of the die 32) is circular. In addition, the diameter of each through hole 33 is constant in the thickness direction of the die 32. That is, each through hole 33 is formed as a cylindrical space.

[0027] The die 32 includes a portion 32a (first portion) having a first temperature during extrusion granulation, and a portion 32b (second portion) having a second temperature during extrusion granulation. The first temperature is equal to or higher than the melting point of the plastic contained in the granulation material. The second temperature is lower than the melting point. When two or more types of plastics with different melting points are contained in the granulation material, the first temperature may be equal to or higher than the melting point of the plastic with the lowest melting point, and the second temperature may be lower than the melting point of the plastic. When the melting point of the plastic is M°C, the first temperature and the second temperature are preferably equal to or higher than (M+5)°C and equal to or lower than (M-5)°C, and more preferably equal to or higher than (M+10)°C and equal to or lower than (M-10)°C. The temperature of the die 32 is measured on the inner surface of the through hole 33. During extrusion granulation, the die 32 is controlled so that the temperature (first temperature) of the portion 32a is equal to or higher than the melting point of the plastic, and the temperature (second temperature) of the portion 32b is lower than the melting point. Such temperature control can be performed, for example, by providing a heater for heating the portion 32a and a heater for heating the portion 32b separately. Each of the portions 32a and 32b may be heated by induction heating.

[0028] In this example, the portion 32a is located inside the portion 32b. That is, the portion 32a is located closer to the rotation axis 35 described later than the portion 32b. In a plan view, the portion 32a is a disk-shaped region, and the portion 32b is an annular region. A heat insulating material 38 is provided at the boundary between the portion 32a and the portion 32b. That is, the portion 32a and the portion 32b are separated by the heat insulating material 38. The heat insulating material 38 is provided in a cylindrical shape and extends from the front surface (the surface on the inlet side of the granulated material) to the back surface (the surface on the outlet side of the granulated material) of the die 32. As a material for the heat insulating material 38, for example, a plastic having a melting point sufficiently higher than the first temperature can be used.

[0029] The multiple through holes 33 include through holes 33a (first through holes) and through holes 33b (second through holes). The through holes 33a and the through holes 33b are present in the parts 32a and 32b of the die 32, respectively. The diameter of the through holes 33a is equal to the diameter of the through holes 33b. In this embodiment, the multiple through holes 33 consist only of the through holes 33a and the through holes 33b. The number of the through holes 33b provided in the die 32 is preferably 30% or more and 70% or less of the total number of the through holes 33a and the through holes 33b provided in the die 32, and more preferably 40% or more and 60% or less.

[0030] A roller 34 is provided on the surface side of the die 32. The roller 34 is cylindrical, and its central axis extends in the radial direction of the die 32. In this example, a plurality of rollers 34 (specifically, four) are provided. One end of each roller 34 is connected to a rotating shaft 35 located at the center of the surface of the die 32. The rotating shaft 35 is configured to rotate (spin) around its central axis. Each roller 34 rotates (revolves) around the rotating shaft 35 while rotating (spinning) around its central axis. In this way, the roller 34 pushes the granulated material into each through hole 33 while revolving around the rotating shaft 35. The roller 34 can pass over the entrances of all the through holes 33 provided in the die 32.

[0031] A cutter 36 is provided on the back side of the die 32. The cutter 36 extends from the center of the back side of the die 32 in the radial direction of the die 32. The cutter 36 cuts the granulated material extruded from each through hole 33 while rotating along the back side of the die 32. In detail, the cutter 36 rotates around the center of the die 32 as an axis in a plane parallel to the back side of the die 32. The cutter 36 is configured to be able to rotate independently of the roller 34. The cutter 36 can pass over the outlets of all the through holes 33 provided in the die 32.

[0032] When the first and second granule forming steps are performed using the extrusion granulator 30, as shown in FIG. 5, the granulated material M1 supplied to the front side of the die 32 is forced into the through hole 33 by the roller 34 rolling on the front side of the die 32. At this time, the die 32 is controlled as described above so that the temperature of the portion 32a is equal to or higher than the melting point of the plastic and the temperature of the portion 32b is lower than the melting point. Specifically, the die 32 is controlled so that the temperature of the inner surface of the through hole 33a is equal to or higher than the melting point of the plastic and the temperature of the inner surface of the through hole 33b is lower than the melting point just before the granulated material passes through. The granulated material M1 forced into the through hole 33 is extruded from the back side of the die 32. When the granulated material M1 is extruded, the cutter 36 continues to rotate on the back side of the die 32. As a result, the granulated material M1 extruded from the through hole 33 is cut by the cutter 36 as shown in FIG. 6. The granulated material thus formed becomes the granular material 10 or the granular material 20.

[0033] In more detail, the plastic melts in the granulated material passing through the through-hole 33a in the portion 32a, whereas the plastic does not melt in the granulated material passing through the through-hole 33b in the portion 32b. The molten plastic enters the voids in the granulated material and blocks the voids. These voids become paths through which liquids such as urine can penetrate into the granulated material. This makes it possible to obtain hydrophobic granulated material 10 from the granulated material that has passed through the through-hole 33a, and to obtain water-absorbent granulated material 20 from the granulated material that has passed through the through-hole 33b.

[0034] The effect of this embodiment will be described. In this embodiment, the granular body 10 having hydrophobicity and the granular body 20 having water absorption are formed. The granular body 10 and the granular body 20 are made of materials of the same composition. Therefore, it is not necessary to prepare the material constituting the granular body 10 and the material constituting the granular body 20 separately. In addition, when there are multiple types of materials constituting each of the granular bodies 10 and 20, "preparation" includes not only procuring each material but also mixing the materials in a predetermined ratio. Sharing the material of the granular body 10 and the granular body 20 in this way contributes to reducing the manufacturing cost of the excrement treatment material 1. Therefore, an excrement treatment material 1 suitable for low-cost manufacturing, and a manufacturing method thereof, have been realized, despite including two types of granular bodies (granular body 10 and granular body 20) with different properties.

[0035] In this way, even if granules 10 and granules 20 are made of materials of the same composition, different properties can be imparted to granules 10 and granules 20 by changing the granulation conditions (die temperature, pressure applied to the granulated material, etc.).

[0036] From the viewpoint of obtaining an excrement treatment material 1 in which granules 10 and granules 20 are mixed in a well-balanced manner, the number of granules 20 is preferably 30% or more and 70% or less of the total number of granules 10 and 20, and more preferably 40% or more and 60% or less.

[0037] When the apparent density of the granular body 10 is greater than that of the granular body 20, there is less room for liquid to penetrate into the interior of the granular body 10, which is advantageous for increasing the liquid permeability of the granular body 10. The same is true when the porosity of the granular body 10 is less than that of the granular body 20. Note that in order to increase the apparent density of the granular body 10 or decrease the porosity of the granular body 10, the pressure applied to the first granulated material during granulation of the granular body 10 may be increased.

[0038] When the average particle size of the plastic contained in the granules 10 is larger than the average particle size of the plastic contained in the granules 20, the plastic melted during granulation of the granules 10, but did not melt during granulation of the granules 20. In other words, in the granules 10, the plastic that melted and deformed during granulation resolidified, and the average particle size of the plastic became large. Therefore, the fact that the average particle size of the plastic contained in the granules 10 is large is evidence that the plastic melted so as to fill the voids inside the granules 10.

[0039] When the granular materials 10 and 20 are mainly made of organic matter, it is possible to obtain an excrement treatment material 1 suitable for incineration. This contributes to the convenience of disposing of used excrement treatment material 1. In particular, when the granular materials 10 and 20 are made only of organic matter, it is possible to obtain an excrement treatment material 1 that is even more suitable for incineration.

[0040] The granular materials 10 and 20 are granulated materials whose surfaces are not coated. Therefore, the granular materials 10 and 20 can be formed without carrying out a process for coating the surfaces of the granulated materials. This also contributes to reducing the manufacturing cost of the excrement treating material 1.

[0041] When the first and second granular material forming steps are carried out simultaneously using the same device, there is no need to carry out a step of mixing the granular material 10 and the granular material 20 after carrying out the first and second granular material forming steps. This also contributes to reducing the manufacturing cost of the excrement treating material 1.

[0042] The present invention is not limited to the above embodiment, and various modifications are possible. In the above embodiment, the particle size of the granular body 10 is equal to the particle size of the granular body 20. However, the particle size of the granular body 10 may be smaller than the particle size of the granular body 20. In order to reduce the particle size of the granular body 10 in this manner, for example, the diameter of the through hole through which the first granulated material passes during extrusion granulation may be reduced. The smaller the diameter of the through hole, the higher the pressure applied to the first granulated material passing through the through hole. This is advantageous for increasing the liquid passing rate of the granular body 10. However, the particle size of the granular body 10 may be larger than the particle size of the granular body 20.

[0043] In the above embodiment, the case where the granular material 10 and the granular material 20 contain plastic has been exemplified. However, the granular material 10 and the granular material 20 do not have to contain plastic. [Explanation of symbols]

[0044] 1. Waste treatment materials 10 Granules 30 Extrusion Granulator 32 Dice Part 32a (first part) Part 32b (Second Part) 33 Through hole 33a through hole (first through hole) 33b through hole (second through hole) 34 Roller 35 Rotational Axis 36 Cutter 38 Insulation M1 Granulation material

Claims

1. A first granular material having hydrophobic properties; a second granular body made of a material having the same composition as the first granular body and having water absorption properties; An excrement treatment material comprising:

2. The excrement treating material according to claim 1, The excrement treating material includes a plurality of first and second granular bodies.

3. The excrement treating material according to claim 2, The number of the second granular bodies is 30% or more and 70% or less of the total number of the first and second granular bodies.

4. The excrement treating material according to claim 3, The number of the second granular bodies is 40% or more and 60% or less of the total number of the first and second granular bodies.

5. The excrement treating material according to any one of claims 1 to 4, The particle size of the first granular material is smaller than the particle size of the second granular material.

6. The excrement treating material according to any one of claims 1 to 4, The apparent density of the first granular material is greater than the apparent density of the second granular material.

7. The excrement treating material according to any one of claims 1 to 4, The excrement treating material, wherein the porosity of the first granular material is smaller than the porosity of the second granular material.

8. The excrement treating material according to any one of claims 1 to 4, The first and second granular bodies are excrement treating materials containing plastic.

9. The excrement treating material according to claim 8, An excrement treatment material, wherein the average particle size of the plastic contained in the first granules is larger than the average particle size of the plastic contained in the second granules.

10. The excrement treating material according to any one of claims 1 to 4, The first and second granular bodies are excrement treating materials whose main component is organic matter.

11. The excrement treating material according to claim 10, The first and second granular bodies are excrement treating materials consisting of only organic matter.

12. The excrement treating material according to any one of claims 1 to 4, The first and second granular bodies are excrement treating materials which are granulated bodies having uncoated surfaces.

13. a first granular material forming step of forming a first granular material having hydrophobic properties; a second granular body forming step of forming a second granular body having the same composition as the first granular body and having water absorbency; A method for producing an excrement treating material, comprising:

14. The method for producing an excrement treating material according to claim 13, A method for producing an excrement treating material, wherein the first and second granular material forming steps are carried out simultaneously using the same apparatus.

15. The method for producing an excrement treating material according to claim 13, In the first granular body forming step, a plurality of the first granular bodies are formed, In the second granular body forming step, a plurality of the second granular bodies are formed.

16. The method for producing an excrement treating material according to claim 15, A manufacturing method for excrement treatment material, in which the second granular body forming process forms the second granular bodies so that the number of the second granular bodies is 30% or more and 70% or less of the sum of the numbers of the first and second granular bodies.

17. The method for producing an excrement treating material according to claim 16, A manufacturing method for excrement treatment material, in which the second granular body forming process forms the second granular bodies so that the number of the second granular bodies is 40% or more and 60% or less of the sum of the numbers of the first and second granular bodies.

18. The method for producing an excrement treating material according to any one of claims 13 to 17, A method for manufacturing an excrement treatment material, in which in the first granular material forming step, the first granular material is formed so that the particle size of the first granular material is smaller than the particle size of the second granular material.

19. The method for producing an excrement treating material according to any one of claims 13 to 17, A method for manufacturing an excrement treatment material, in which in the first granular body forming process, the first granular body is formed so that the apparent density of the first granular body is greater than the apparent density of the second granular body.

20. The method for producing an excrement treating material according to any one of claims 13 to 17, A method for manufacturing an excrement treatment material, in which in the first granular body forming process, the first granular body is formed so that the porosity of the first granular body is smaller than the porosity of the second granular body.

21. The method for producing an excrement treating material according to any one of claims 13 to 17, In the first and second granular body forming steps, the first and second granular bodies each contain a plastic.

22. The method for producing an excrement treating material according to claim 21, A method for manufacturing excrement treatment material, in which the first granular body forming process forms the first granular body so that the average particle size of the plastic contained in the first granular body is larger than the average particle size of the plastic contained in the second granular body.

23. The method for producing an excrement treating material according to any one of claims 13 to 17, In the first and second granular body forming steps, the first and second granular bodies are formed, respectively, from organic matter as a main material.

24. The method for producing an excrement treating material according to claim 23, In the first and second granular body forming steps, the first and second granular bodies are formed, respectively, from only organic matter.

25. The method for producing an excrement treating material according to any one of claims 13 to 17, In the first and second granular body forming steps, the first and second granular bodies are formed, respectively, as granules having uncoated surfaces.

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