Method for manufacturing recycled resin material containing concrete waste, and method for manufacturing recycled molded product containing concrete waste

Abstract

The present invention aims to provide a method for producing recycled resin materials in which part of the raw materials are concrete waste, and which results in a recycled resin material with higher rigidity compared to a method in which the mixed body is humidified after the mixing process. [Solution] A method for producing recycled resin material Ps using concrete waste C1 as part of the raw materials includes: a crushing step S11 in which concrete waste C1 is crushed to produce concrete powder C2; a humidity control step S13 in which the concrete powder C2 is dehumidified or humidified for a predetermined amount of time to produce humidity-controlled concrete powder C4 with a weight moisture content within a predetermined range; a stirring step S14 in which resin granules R composed of a plurality of resin particles and humidity-controlled concrete powder C4 are stirred to produce composite granules M1; and a kneading step S15 in which the composite granules M1 is kneaded while being heated to produce a kneaded body M2.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a recycled resin material using a part of raw materials as concrete waste. The present invention also relates to a method for manufacturing a molded product using a part of raw materials as concrete waste.

Background Art

[0002] In Patent Document 1, an invention according to Claim 3 below is disclosed for the purpose of providing a method for manufacturing a recycled plastic material. ======================================== (Claim 3) A step of preparing at least one waste material selected from the group consisting of waste materials of building materials containing a concrete component, ceramic waste materials, and waste materials of calcium silicate boards; A step of preparing plastic; A step of melt-mixing the waste material and the plastic; A step of processing the melt mixture into pellets and drying it, comprising, In the step of melt-mixing, the waste material and the plastic are melt-mixed at a mass ratio of the waste material: the plastic = 20:80 to 40:60, A method for manufacturing a pellet-shaped recycled plastic material. ======================================== The invention according to this Claim 3 requires, at least, (1) melt-mixing a previously prepared waste material of building materials or the like and plastic, and (2) then processing the melt mixture into pellets and drying it to manufacture a pellet-shaped recycled plastic material.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

[0004] The inventors of this application conducted experimental research on a method for producing recycled resin material using concrete waste as part of the raw materials, and succeeded in finding a method for producing recycled resin material with higher rigidity than the invention described in claim 3 of Patent Document 1 (method for producing recycled plastic material).

[0005] One of the objectives of the present invention is to provide a method for producing recycled resin materials in which part of the raw materials are concrete waste, and which produces recycled resin materials with higher rigidity compared to a method in which the mixed body is humidified after the mixing process. [Means for solving the problem]

[0006] In the first embodiment, the method for manufacturing recycled resin material using concrete waste as part of the raw materials (hereinafter referred to as the "method for manufacturing recycled resin material") is: A method for manufacturing recycled resin material, in which concrete waste is used as part of the raw materials, A crushing process that crushes concrete waste to produce concrete powder, A humidity control step is performed to produce humidity-controlled concrete powder in which the concrete powder generated in the crushing step is dehumidified or humidified for a predetermined time to a predetermined weight moisture content within a predetermined range. A stirring step in which a resin granule body composed of multiple resin particles and a humidity-controlled concrete powder produced in the humidity-control step are stirred together to produce a composite granule body, A kneading step is performed to knead the composite granules generated in the stirring step while heating them to produce a kneaded body, Includes.

[0007] The method for manufacturing recycled resin material according to the second embodiment is: In the manufacturing method of the first embodiment, The weight moisture content within the predetermined range is 5% by weight or more and 10% by weight or less.

[0008] The manufacturing method of the recycled resin material of the third aspect is as follows: In the manufacturing method of the first aspect or the second aspect, In the pulverization step, the concrete waste material is pulverized so that the average particle diameter of the concrete powder is smaller than the average particle diameter of the plurality of resin particles.

[0009] The manufacturing method of the recycled resin material of the fourth aspect is as follows: In the manufacturing method of any one of the first aspect to the third aspect, In the stirring step, a composite granule as an aggregate of a plurality of resin particles each coated with the humidity-adjusted concrete powder is generated.

[0010] The manufacturing method of the recycled resin material of the fifth aspect is as follows: In the manufacturing method of any one of the first aspect to the fourth aspect, Furthermore, A removal step that is performed before the humidity adjustment step and removes a part of the concrete powder generated in the pulverization step, is included, The particle diameter of the part is larger than 500 μm.

[0011] The manufacturing method of the recycled resin material of the sixth aspect is as follows: In the manufacturing method of any one of the first aspect to the fifth aspect, The ratio of fine particles having a particle diameter of 100 μm or more in the concrete powder generated in the pulverization step is 50% or more.

[0012] The manufacturing method of the recycled resin material of the seventh aspect is as follows: In the manufacturing method of any one of the first aspect to the sixth aspect, In the pulverization step, when pulverizing the concrete waste material, a part of the solid other than the cement material contained in the concrete waste material is removed to generate the concrete powder.

[0013] The manufacturing method of the recycled resin material of the eighth aspect is as follows: In the manufacturing method of any one of the first aspect to the seventh aspect, In the humidity conditioning step, after humidifying the concrete powder generated in the pulverization step to a specific ratio exceeding the upper limit ratio of the weight moisture content within the predetermined range, dehumidification is performed to generate a humidity-conditioned concrete powder having a weight moisture content within the predetermined range.

[0014] The method for manufacturing a recycled resin material according to the ninth aspect is In the manufacturing method according to any one of the first to eighth aspects, Furthermore, A dividing step of dividing the kneaded body generated in the kneading step to generate a plurality of pellets, is included.

[0015] A method for manufacturing a regenerated molded product (hereinafter referred to as a method for manufacturing a regenerated molded product) in which a part of the raw material in one aspect is a concrete waste material is The manufacturing method according to the ninth aspect and A molding step of processing the plurality of pellets generated in the dividing step to mold a molded product having a predetermined shape, is included.

Advantages of the Invention

[0016] The manufacturing methods of the recycled resin materials according to the first aspect and the third to ninth aspects can manufacture a recycled resin material having higher rigidity than when the kneaded body is humidity-conditioned after the kneading step.

[0017] The manufacturing method of the recycled resin material according to the second aspect can manufacture a recycled resin material having higher rigidity than when the weight moisture content within the predetermined range is greater than 10% by weight.

[0018] The manufacturing method of the regenerated molded product in one aspect can manufacture a regenerated molded product having higher rigidity than when the kneaded body is humidity-conditioned after the kneading step.

Brief Description of the Drawings

[0019] [Figure 1] It is a process diagram of the method for manufacturing a regenerated molded product according to an embodiment of the present invention (hereinafter referred to as the present embodiment). [Figure 2]This is a schematic diagram showing the relationship between multiple resin particles and humidity-controlled concrete powder before and after the stirring process in this embodiment. [Figure 3] This is a process diagram of the manufacturing method for the first comparative form of a recycled molded product. [Figure 4] This table summarizes the manufacturing conditions for the first test and the measurement results for each sample. [Figure 5] This table summarizes the manufacturing conditions for the second test and the measurement results for each sample. [Figure 6] This table summarizes the manufacturing conditions for the third test and the measurement results for each sample. [Figure 7] This table summarizes the manufacturing conditions for Test 4 and the measurement results for each sample. [Figure 8] This table summarizes the manufacturing conditions for Test 5 and the measurement results for each sample. [Figure 9] This table summarizes the manufacturing conditions for Test 6 and the measurement results for each sample. [Figure 10] This table summarizes the manufacturing conditions for Test 7 and the measurement results for each sample. [Figure 11] This table summarizes the manufacturing conditions for Test 8 and the measurement results for each sample. [Modes for carrying out the invention]

[0020] ≪Overview≫ The following describes this embodiment. Next, several modified examples will be described.

[0021] This embodiment First, the manufacturing method S20 of the recycled molded product MP (an example of a molded product) according to this embodiment will be described. Next, the effects of this embodiment will be described.

[0022] <Method for manufacturing recycled molded product MP according to this embodiment> Figure 1 is a process diagram of the manufacturing method S20 for the recycled molded product MP in this embodiment. The manufacturing method S20 for recycled molded product MP includes, as an example, a manufacturing method S10 for recycled resin material (one example being a plurality of pellets Ps) and a molding step S21 that is performed thereafter. A sample of recycled resin material is a mixture of multiple pellets (Ps), which are formed by kneading resin with powdered concrete (concrete waste C1) and concrete powder (concrete powder C2), and then dividing the resulting mixture into predetermined shapes. Recycled molded products (MP) include boards, flooring materials, and other molded materials. The manufacturing method S10 for recycled resin material includes steps S11 to S16, and each step is performed in the order described. However, of steps S11 to S16, the removal step S12 is not an essential step, as will be explained later in the description of the effects of this embodiment. In other words, the essential steps of the manufacturing method S10 for recycled resin material are the crushing step S11, the humidity control step S13, the stirring step S14, the kneading step S15, and the dividing step S16. Furthermore, when manufacturing only one recycled resin material, the dividing step S16 is also not an essential step. The following describes each step in the manufacturing method S20 for recycled molded product MP.

[0023] (Grinding process S11) The crushing process S11 involves crushing concrete waste C1 to produce concrete powder C2, for example, by using a crusher (not shown in the figure). In the crushing step S11, the concrete waste material C1 is crushed so that the average particle size of the concrete powder C2 is 500 μm or less, preferably 300 μm or less. The concrete powder C2 produced in the crushing process S11 is generated such that its average particle size (for example, 500 μm or less) is smaller than the average particle size of the multiple resin particles R described later (for example, 3 mm to 10 mm). In the crushing step S11, it is preferable to crush the concrete waste C1 such that the proportion of fine particles with a particle size of 100 μm or larger (ratio by number) in the generated concrete powder C2 is 50% or more. In the crushing process S11, it is preferable to remove some of the solid material other than cement contained in the concrete waste C1 during the crushing process to produce concrete powder C2. Here, the aforementioned "solid material" refers to granular material (aggregate) such as gravel and sand. Generally, concrete is a composite material made by mixing (1) granular material (aggregate) such as gravel and sand and (2) a binder (cement paste) consisting of cement and water and hardening it. Cement material refers to concrete from which (1) granular material (aggregate) such as gravel and sand has been removed.

[0024] (Removal process S12) The removal process S12 is performed after the crushing process S11 and before the humidity control process S13, which will be described later. In the removal step S12, a portion of the concrete powder C2 generated in the crushing step S11 is removed, for example, by using a sieve mesh (not shown). This portion is, for example, an aggregate of particles or fine particles with a particle size larger than 500 μm. Here, in this specification, a particle is defined as having a particle size of 1 mm or more, and fine particles are defined as having a particle size of less than 1 mm. After the removal process S12, the concrete powder C2 is separated into (1) aggregates of fine particles with a particle size of 500 μm or less (hereinafter referred to as concrete powder C3) and (2) aggregates of fine particles and particles with a particle size larger than 500 μm. As mentioned above, the removal process S12 is not a mandatory process.

[0025] (Humidity control process S13) The humidity control process S13 adjusts the moisture content of the concrete powder C3, which is separated in the removal process S12 from the concrete powder C2 generated in the crushing process S11, to a predetermined weight moisture content, thereby producing humidity-controlled concrete powder C4. In the humidity control process S13, for example, a heating device with humidification and dehumidification functions (not shown) is used to dehumidify or humidify the concrete powder C3 over a predetermined period of time (for example, 1 hour) so that the weight moisture content is between 4% and 10% (an example within a predetermined range). Here, if the weight moisture content of the concrete powder C3 is 10% or more before the humidity control process S13, the concrete powder C3 will be dehumidified as a result of the humidity control process S13. Conversely, if the weight moisture content of the concrete powder C3 is less than 4% before the humidity control process S13, the concrete powder C3 will be humidified as a result of the humidity control process S13. Furthermore, when dehumidifying in the humidity control step S13, it is preferable to perform the process while stirring the concrete powder C3. This is because, as demonstrated by the inventors' tests, stirring helps to more even out the amount of moisture contained in each particle, resulting in the production of a recycled molded product with higher rigidity. In addition, this process can suppress variations in the coating when the resin granules R are coated with the humidity-controlled concrete powder C4 during the subsequent stirring step S14. Consequently, the concrete powder C4 can be mixed more uniformly with the resin in the mixing step S15, resulting in the production of a recycled molded product with higher rigidity.

[0026] (Agitation process S14) The stirring step S14 involves mixing multiple resin particles R (hereinafter also referred to as resin granules R) with the humidity-controlled concrete powder C4 produced in the humidity-controlled step S13 to produce composite granules M1. In the stirring step S14, for example, a stirring device (not shown) is used to stir multiple resin particles R and humidity-controlled concrete powder C4 using rotating blades (not shown) that rotate around the axis of the stirring device, thereby generating composite granules M1.

[0027] <Multiple resin particles (resin granules)> Here, the resin granules R are not limited to, but include, for example, powders of resins that can be processed into molded products (i.e., resins that can be thermoplasticized), such as polyvinyl chloride (PVC), polypropylene (PP), HD polyethylene (HDPE), HI polystyrene (HI-PS), ABS resin (ABS), and PBT polybutylene terephthalate. The resin granules R may also be a composite of two or more resins. Furthermore, the resin granules R may be new resin (virgin plastic), recycled resin (recycled plastic), or a mixture of both. The average particle size of the multiple resin particles that make up the resin granules R is, for example, 3 mm to 10 mm. In other words, the average particle size of the multiple resin particles R is larger than the average particle size of the concrete powder C2 and concrete powder C3.

[0028] <Composite granules> As described above, the composite granules M1 are produced by agitating the resin granules R and the humidity-controlled concrete powder C4 using rotating blades (not shown) that rotate around an axis provided by an agitator (not shown). In this case, multiple humidity-controlled concrete powder C4 particles adhere to the surface of each resin particle constituting the resin granules R. Therefore, each resin particle R is covered with humidity-controlled concrete powder C4 (see Figure 2). In other words, the composite granules M1 produced by the agitation process S14 are not simply a uniform mixture of multiple resin particles constituting the resin granules R and multiple fine particles constituting the humidity-controlled concrete powder C4, but rather an aggregate of resin granules R each covered with humidity-controlled concrete powder C4. Here, the maximum weight ratio (weight %) of the moisture-conditioned concrete powder C4 in the composite granules M1 is preferably at most about 80%.

[0029] (Kneading process S15) The kneading step S15 involves heating and kneading the composite granules M1 generated in the stirring step S14 to produce a kneaded body M2. In the mixing process S15, for example, by using a mixing device (not shown), the composite granules M1 are mixed while heating the screw (not shown) that makes up the mixing device to a temperature approximately equal to the melting point of the resin granules R (resin) contained in the composite granules M1, thereby producing a mixed body M2. Here, the temperature approximately the melting point of the resin granules R (resin) refers to a temperature at which the fine particles constituting the composite granules M1 melt and become syrup-like, but during the kneading process S15, less than 30% of the resin decomposition occurs. For example, if the resin granules R are an aggregate of polyvinyl chloride resin fine particles, the temperature approximately the melting point is, as an example, 130°C to 160°C.

[0030] (Dividing process S16) The division process S16 is a process in which the kneaded body M2 produced in the kneading process S15 is divided into multiple parts to produce multiple pellets Ps, each having a predetermined shape. Furthermore, the completion of all processes from the crushing process S11 to the dividing process S16 signifies the completion of the manufacturing method S10 for recycled resin material in this embodiment.

[0031] (Molding process S21) The molding process S21 is performed after the manufacturing method S10 of the recycled resin material, that is, after the splitting process S16. In the molding process S21, for example, multiple pellets Ps generated in the splitting process S16 are processed to form a recycled molded product MP of a predetermined shape. Processing here refers to methods such as injection molding, extrusion molding, and blow molding. Furthermore, the completion of the molding process S21 following all processes from the crushing process S11 to the dividing process S16 signifies the completion of the manufacturing method S20 for recycled molded products in this embodiment.

[0032] The above is a description of the manufacturing method S10 for recycled molded products according to this embodiment.

[0033] <Effects of this embodiment> Next, the effects of this embodiment will be described.

[0034] The inventors of this invention derived the method for manufacturing recycled molded articles MP in this embodiment by conducting tests comparing (1) the multiple physical properties of multiple recycled molded articles MP (recycled molded articles MP11, MP12, MP13, ...) manufactured according to this embodiment with (2) the multiple physical properties of multiple comparative molded articles RP (RP11, RP21, ...) manufactured by two types of comparative manufacturing methods described later. The following will describe (1) the manufacturing methods for multiple recycled molded products MP and multiple comparative molded products RP, (2) the measurement methods for multiple physical properties, and (3) finally, a discussion of the test results.

[0035] (Manufacturing method) <Multiple recycled molded parts (MP)> Multiple recycled molded products MP were manufactured according to the manufacturing method of this embodiment described above (Figure 1). Furthermore, each of the tables in Figures 4 to 11 (Tables 1 to 8) shows the specific conditions for each process and the measured physical property values. The difference between the tables lies in the difference in the resin constituting the resin granules R, as follows.

[0036] [Resins used in each test] ======================================== Test 1 (see table in Figure 4): Polyvinyl chloride (new) Test 2 (see table in Figure 5): Polyvinyl chloride (recycled) Third test (see table in Figure 6): Polypropylene (new) Test 4 (see table in Figure 7): HD polyethylene (new) Test 5 (See table in Figure 8) HI Polystyrene (new) Test 6 (See table in Figure 9) ABS (new) Test 7 (see table in Figure 10): Polyethylene (new) and polypropylene (new) (50% by weight:50%) Test 8 (See Table 8 in Figure 11): PBT polybutylene terephthalate (new) ========================================

[0037] <Multiple comparative molded parts> As mentioned above, the multiple comparative molded products RP were manufactured using two different comparative manufacturing methods.

[0038] [Method for manufacturing recycled molded product of the first comparative form] Of the multiple comparative molded products RP, comparative molded products RP11, RP21, RP31, RP41, RP51, RP61, RP71, and RP81 were manufactured in accordance with the manufacturing method S20C (S10C is a manufacturing method for recycled resin material (see Figure 3)) of the first comparative form of recycled molded product. The manufacturing method S20C of the first comparative embodiment is similar to the manufacturing method S20 of this embodiment in that the grinding step S11, removal step S12, stirring step S14, kneading step S15, dividing step S16, and molding step S21 are performed in the order described above. However, the manufacturing method S20 of this embodiment performs the humidity control step S13 after the removal step S12 and before the stirring step S14, whereas the manufacturing method S20C of the first comparative embodiment differs in that it does not perform the humidity control step S13 after the removal step S12 and before the stirring step S14, but instead performs a drying step S23 similar to the humidity control step S13 after the dividing step S16 and before the molding step S21. As described above, the manufacturing methods for the comparative molded products RP11, RP21, ... of the first comparative form can be said to be forms included in the invention described in claim 3 of the aforementioned Patent Document 1.

[0039] [Method for manufacturing recycled molded products in the second comparative form] Of the multiple comparative molded products RP, comparative molded products RP12, RP22, ... other than comparative molded products RP11, RP21, RP31, RP41, RP51, RP61, RP71, and RP81 were manufactured according to the flow of the manufacturing method S20 (Figure 1) of this embodiment described above. These comparative molded products do not meet the humidity control conditions in the humidity control process S13 of this embodiment (weight moisture content of 4% or more and 10% or less). Specifically, the manufacturing method of the second comparative embodiment differs from the manufacturing method S20 of this embodiment in that the humidity control process S13 controls the weight moisture content of the concrete powder C3 to 20% ± 3%, thereby producing humidity-controlled concrete powder C4.

[0040] (Multiple methods for measuring physical properties) <Bending stress> Bending stress (N / mm 2 The values ​​were measured in accordance with JIS K7171. The bending test speed was set to 2 mm / min. Here, N is kg·m / sec. 2 This means (and so on). <Flexural modulus> Flexural modulus (N / mm²) 2 The measurements were taken in accordance with JIS K7171. The bending test speed was set to 2 mm / min. <Tensile stress> Tensile stress (N / mm 2 The measurements were taken in accordance with JIS K7161. The tensile test speed was set to 1 mm / min. <Tensile modulus> Tensile modulus (N / mm²) 2 The measurements were taken in accordance with JIS K7161. The tensile test speed was set to 1 mm / min. Charpy impact strength Charpy impact strength (kJ / m 2 The measurement was performed in accordance with JIS K7111-1. A notch-type pendulum-type impact tester (not shown) was used, and the impact energy was set to 4 J.

[0041] (Test results and discussion) Next, the results of the first to eighth tests will be explained, referring to the tables in Figures 4 to 11.

[0042] <Comparison with the first comparative form> [Comparison results with the first comparative form] In each test, all recycled molded products MP11, MP21, MP31, ... manufactured by the manufacturing method of this embodiment showed higher measured values ​​of stiffness (bending stress, bending modulus of elasticity, and tensile stress) than recycled molded products RP11, RP21, RP31, RP41, RP51, RP61, RP71, and RP81 manufactured by the manufacturing method of the first comparative embodiment. Since this result is true for all tests, it can be seen that the manufacturing method of this embodiment is not dependent on the type of resin granules R (resin). It can also be seen that it is not dependent on whether the resin is new or recycled. Furthermore, it can be seen that it is not dependent on whether the resin is a single product or a mixture. Therefore, the manufacturing method for recycled molded articles and recycled resin materials of this embodiment can produce recycled molded articles (recycled resin materials) with higher rigidity compared to the manufacturing method of the first comparative embodiment.

[0043] [Consideration of the comparison results with the first comparative form] In the first comparative configuration, as shown in Figure 3, the drying process (humidification process) S23 is performed after the stirring process S14 and the mixing process S15. In this configuration, the concrete powder C2 used in the stirring process S14 and the mixing process S15 is not humidified (in other words, it contains a lot of moisture, such as more than 20% by weight). Then, after the mixing process S15, the drying process (humidification process) S23 is performed, causing a lot of moisture to evaporate from the recycled resin material. In contrast, in this embodiment, as shown in Figure 1, the concrete powder C3 is conditioned by the humidity conditioning process S13 to produce humidity-conditioned concrete powder C4 before the stirring process S14 and the mixing process S15 are performed. In this embodiment, even if the concrete powder C2 contains a large amount of moisture, the humidity-conditioned concrete powder C4, from which much of the moisture has been removed, is used in the stirring process S14 and the mixing process S15. In the first comparative embodiment, moisture tends to remain inside the manufactured recycled molded product, whereas this is not the case in this embodiment. Furthermore, in the first comparative embodiment, the recycled resin material is dried, causing voids to form inside after the moisture evaporates, whereas in this embodiment, the recycled resin material is made from pre-dried powder, making it less likely for voids to form inside as in the first comparative embodiment. The above is a discussion of the comparison results between this embodiment and the first comparative embodiment.

[0044] <Comparison with the second comparative form> [Comparison results with the second comparison form] In each test, all recycled molded products MP11, MP21, MP31, ... manufactured by the manufacturing method of this embodiment showed higher measured values ​​of stiffness (bending stress, bending modulus of elasticity, and tensile stress) than all recycled molded products RP12, RP22, RP33, ... manufactured by the manufacturing method of the second comparative embodiment. Since this result is true for all tests, it can be seen that the manufacturing method of this embodiment is not dependent on the type of resin granules R (resin). It can also be seen that it is not dependent on whether the resin is new or recycled. Furthermore, it can be seen that it is not dependent on whether the resin is a single product or a mixture. Therefore, the manufacturing method for recycled molded articles and recycled resin materials of this embodiment can produce recycled molded articles (recycled resin materials) with higher rigidity compared to the manufacturing method of the second comparative embodiment.

[0045] [Consideration of the comparison results with the second comparative form] In the second comparative embodiment, all recycled molded products RP12, RP13, ... are manufactured using a process similar to the manufacturing method of this embodiment (see Figure 1). However, in the second comparative embodiment, although a humidity control process is performed, the weight percentage of moisture in the concrete powder after humidity control is 11% or more in all cases. In contrast, in this embodiment, in all cases, the weight percentage of moisture in the conditioned concrete powder C4 after the conditioned process S13 is set to 4% or more and 10% or less. In this embodiment, as in the second comparative embodiment, the weight percentage of moisture in the conditioned concrete powder C4 after the moisture conditioning process S13 is never less than 4% (see Figures 4 to 11). The inventors of this application actually attempted to test this, but stopped the process during the stirring process S14 because combustion problems occurred due to collisions between particles or between particles and rotating blades (not shown) in the stirring chamber of the stirring device (not shown). This is thought to be because the moisture content was too low, causing the particles to burn due to the energy of the collisions. Given this background, the adjustment is set to 4% or more from the viewpoint of safety and feasibility in the stirring process S14. To return to the main point, in the case of the second comparative embodiment, that is, if the weight percentage of moisture in the moisture-controlled concrete powder C4 after the moisture-controlled process S13 exceeds 10%, it is considered that the rigidity of the resulting recycled molded product is limited by the remaining moisture. In contrast, in this embodiment, if the weight percentage of moisture in the moisture-controlled concrete powder C4 is between 4% and 10%, it is considered that the rigidity, which is not caused by other parameters, is maintained. The above is a discussion of the comparison results between this embodiment and the second comparative embodiment.

[0046] The above is a description of this embodiment.

[0047] ≪Multiple Variations≫ As described above, the present invention has been explained with reference to this embodiment, but the embodiments included in the technical scope of the present invention are not limited to the above-described embodiment.

[0048] For example, the resin granules R may be polyvinyl chloride (PVC), polypropylene (PP), HD polyethylene (HDPE), ... and combinations of two or more of these, but resin granules R other than these resins may be other resins.

[0049] Furthermore, although the above embodiment was described on the premise that moisture is removed from the concrete powder C2 in the humidity control step S13, moisture may be added to a material with a lower moisture content. In this case, it is preferable to vaporize the liquid and add it to the stirred concrete powder C2 rather than adding the liquid to the concrete powder C2. The inventors of this application have tried both cases, and have confirmed that the latter has the advantage of being able to efficiently disperse the moisture, thereby shortening the execution time of the humidity control step S13.

[0050] Furthermore, the manufacturing method of this embodiment described above includes a crushing step S11 in which concrete waste is crushed to produce concrete powder, as shown in Figure 1. However, if concrete powder has already been prepared from concrete waste, the crushing step S11 does not need to be performed. In this case, the manufacturing method of the deformed recycled resin material is as follows. ======================================== A method for manufacturing recycled resin material, in which concrete waste is used as part of the raw materials, A humidity control process involves dehumidifying or humidifying concrete powder obtained from concrete waste for a predetermined period of time to produce humidity-controlled concrete powder with a predetermined weight moisture content, and A stirring step in which a resin granule body composed of multiple resin particles and a humidity-controlled concrete powder produced in the humidity-control step are stirred together to produce a composite granule body, A kneading step is performed to knead the composite granules generated in the stirring step while heating them to produce a kneaded body, including, Manufacturing method. ========================================

[0051] Furthermore, in the humidity control step S13 performed in the manufacturing method of the above-described embodiment, it is often unclear what the total moisture content of the concrete powder obtained from the concrete waste material is, and what the degree of uniformity of the moisture content is. Therefore, in the humidity control process S13, it is possible to humidify the material to a standard weight moisture content (for example, a weight moisture content significantly exceeding a specified range such as 30% by weight (an example of a specific rate)) and then dehumidify it so that the weight moisture content is in the range of 4% to 10%. By adopting this method, greater uniformity of moisture can be achieved. Consequently, it is possible to improve the manufacturing yield and reduce the variation in the quality of the recycled molded products that are the final product.

[0052] The above is an explanation of several variations. [Explanation of Symbols]

[0053] C1 Concrete waste C2 Concrete Powder C3 Concrete Powder C4 Adjusted Concrete Powder M1 composite granules M2 kneaded body MP recycled molded products RP comparative form recycled molded product Ps pellets (an example of recycled resin material) R resin granules (multiple resin particles) S10 Manufacturing method of recycled resin material S11 Grinding process S12 Removal process S13 Humidity Control Process S14 Stirring process S15 Kneading process S16 Splitting process S20 Manufacturing method for recycled molded products Manufacturing method for recycled molded products of S20C, first comparative form. S21 Molding process S23 Drying process

Claims

1. The concrete powder obtained from concrete waste is dehumidified, The composite granules, which are formed by stirring humidified concrete powder and resin granules containing multiple resin particles, are then kneaded while being heated. A method for manufacturing recycled resin material containing concrete waste.

2. The concrete powder obtained from concrete waste is dehumidified, A composite granule is produced by stirring a mixture of humidity-controlled concrete powder and resin granules containing multiple resin particles, and then kneading the resulting composite granules while heating to produce a kneaded body. The resulting compound is divided into multiple pellets. A method for manufacturing recycled resin material containing concrete waste.

3. The concrete powder obtained from concrete waste is dehumidified, A composite granule is produced by stirring a mixture of humidity-controlled concrete powder and resin granules containing multiple resin particles, and then kneading the resulting composite granules while heating to produce a kneaded body. The resulting compound is divided into multiple pellets. The divided pellets are molded into a molded product of a predetermined shape. A method for manufacturing recycled molded products containing concrete waste.

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