JP2018167181A - Recycling method of waste - Google Patents

Abstract

To provide an appropriate and efficient recycling method without requiring trial and error even when no past results for treating the waste exist.SOLUTION: In a recycling method of waste,: implementation steps are selected from predetermined treatment steps including a heating step, a particle size adjustment step, a magnetic force sorting step, a wind power sorting step, an eddy current sorting step, a dry specific gravity sorting step and a water washing step based on chemical compositions and physical properties due to the measurements of the chemical compositions of the waste and the physical properties including the particle size of the waste; the particle size adjustment step and the wind power sorting step in the treatment steps can be made essential; the maximum particle size of the waste can be made 5 mm or more and 30 mm or less; and the heating step can be performed at 650°C or higher and 1,000°C or lower when the waste does not include metallic aluminum and includes a metal without metallic aluminum and organic matter.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for recycling waste, and more particularly, to a method for appropriately and efficiently recycling waste that has not been treated.

Conventionally, the recycling of waste is performed based on a predetermined processing step according to the type of waste. For example, Patent Literature 1 describes a method for recycling waste incineration main ash as a cement raw material. Patent Document 2 describes a method for recycling waste glass as a cement raw material. In addition, municipal waste fly ash, ASR (
Various wastes such as Automobile Shredder Residue are recycled based on predetermined processing steps.

JP 2004-167350 A JP 2002-274900 A

  By the way, among the wastes that are desired to be recycled, there are no treatment results, or there are treatment results by itself, but there is no treatment result for mixed waste in which multiple types of waste are mixed. Exists. In addition, new products will appear, after which new waste will be generated. There is no denying that the properties and composition of wastes that have existed in the past vary and the properties and composition change with the times.

  When recycling new waste without such treatment results, it is necessary to make trial and error again to determine the treatment process, which hinders the improvement of the waste recycling rate, resulting in a large amount of waste. It is landfilled at the final disposal site without being recycled.

  Therefore, the present invention has been made in view of the above-described problem, and an object of the present invention is to provide a method for appropriately and efficiently recycling waste that does not have a treatment record without trial and error. And

  In order to achieve the above object, the present invention provides a waste recycling method, which measures the chemical composition of waste and physical properties including the particle size of the waste, and the measured chemical composition and physical Select a process to be performed from a predetermined group of processing steps including a heating process, a particle size adjustment process, a magnetic force selection process, a wind power selection process, an eddy current selection process, a dry specific gravity selection process, and a water washing process based on the characteristics It is characterized by that.

  According to the present invention, a process to be performed is selected from a predetermined group of processing steps based on the chemical composition and physical properties of the waste. Appropriate treatment steps can be selected, and the waste recycling rate can be improved.

  In the waste recycling method, the particle diameter adjustment step and the wind force selection step can be essential steps. By performing the particle size adjustment process, it is possible to efficiently perform the subsequent eddy current sorting process and the dry specific gravity sorting process, etc., and by the wind sorting process, it is supplied to the subsequent eddy current sorting process, etc. The amount of waste generated can be reduced, and the eddy current sorting step and the like can be performed efficiently.

  In the waste recycling method, the maximum particle size of the waste can be set to 5 mm or more and 30 mm or less by the particle size adjusting step. Thereby, sorting, such as a latter eddy current sorting process and a dry specific gravity sorting process, can be performed efficiently.

  In the waste recycling method, when the waste does not contain metallic aluminum and contains a metal other than metallic aluminum and an organic matter, the heating step can be performed at 650 ° C. or higher and 1000 ° C. or lower. Thereby, organic substance can be burned and it can be made easy to isolate | separate organic substance and a metal.

  In the waste recycling method, when the waste contains metallic aluminum and organic matter, the heating step can be performed at 250 ° C. or higher and lower than 650 ° C. Thereby, it is possible to preserve the calorific value of the organic matter and prevent reuse as a fuel while preventing melting of the metal aluminum, and to make the organic matter brittle and easily separated from the metal.

  When the waste recycling method does not correspond to the heating step of 250 ° C. or higher and 1000 ° C. or lower, and is to be agglomerated, the heating step is performed at 100 ° C. or higher and lower than 250 ° C. Can do. Thereby, the quality of a recovered material can be improved by heat-drying waste that contains moisture and may be aggregated to prevent aggregation in a later step.

  In the waste recycling method, when the waste contains a metal having a magnetic force, the magnetic force sorting step can be performed. Thereby, the metal which has magnetism can be selected and collected from waste.

  In the waste recycling method, when the waste contains metallic aluminum, the eddy current sorting step can be performed. Thereby, metallic aluminum can be sorted and recovered from the waste.

  In the waste recycling method, when the waste contains precious metal and / or copper, the dry specific gravity sorting step can be performed. Thereby, precious metal and copper can be sorted and recovered from the waste.

  In the waste recycling method, when the waste contains chlorine, the water washing step can be performed. As a result, chlorine can be removed from the waste, and it can be used as a raw material for cement.

  As described above, according to the present invention, it is possible to appropriately and efficiently recycle without waste through trial and error only by measuring the chemical composition and physical properties of waste that has not been treated. , The recycling rate can be improved.

It is a part of flowchart for demonstrating the recycling method of the waste which concerns on this invention. It is a part of flowchart for demonstrating the recycling method of the waste which concerns on this invention. It is a part of flowchart for demonstrating the recycling method of the waste which concerns on this invention.

  Next, an embodiment for carrying out the present invention will be described in detail with reference to the drawings.

  1 to 3 are flowcharts for explaining a waste recycling method according to the present invention. In the present invention, the chemical composition and physical properties of the waste to be treated are measured, and a processing step to be performed is selected from a predetermined processing step group based on the measured chemical composition and physical properties.

  The waste to be treated by the waste recycling method according to the present invention is a mixed waste in which two or more kinds of metals, inorganics, and organics are mixed. Examples of such waste include incinerated main ash of combustible waste, incombustible residue and earth and sand glass of incombustible waste and oversized waste, automotive shredder dust, shredder dust of home appliances, waste substrates of home appliances, and waste lithium ion batteries. . Such waste contains metal, organic matter, inorganic matter, etc., and it is required to appropriately recycle each component. Here, examples of the metal include iron, metal aluminum, copper, and noble metals, which can be reused as a metal raw material. Examples of inorganic materials include earth and sand, glass, ash, concrete, and ceramics, which can be reused as civil engineering materials and cement materials. Examples of the organic material include wood waste, plastic, carbon, oil, vegetation, and fiber, which can be reused as fuel.

  Therefore, in the waste recycling method according to the present invention, first, the chemical composition and physical properties of the waste are measured (step S1). For chemical composition, measure the presence or absence of metal, the type of metal and the presence or absence of magnetism, the presence or absence of organic matter, the presence or absence of inorganic matter, and the chlorine content when containing metals. . As for physical properties, the particle size of waste, the presence or absence of moisture, and the possibility of aggregation are measured. Based on the chemical composition and physical properties measured in step S1, the necessity of each subsequent processing step is selected.

  In addition, “include” here is intended to include an amount having a value enough to be recycled because the value of valuable metals and fuels fluctuates with time. That's not it. In general, when it is used as a fuel, it is required to contain about half of the organic matter (or carbon) of the object. On the other hand, even if it is a precious metal, it may be considered worth even if it is several ppm. Moreover, although iron, metal aluminum, copper, and a noble metal were illustrated as a metal, the metal seed | species applicable from now on may be added by the change of value. In the case of adding, it may be determined whether to include in iron, metallic aluminum, copper, or noble metal according to the property.

  Based on the physical properties of the waste measured in step S1, it is determined in step S2 whether the average particle size of the waste is 0.5 mm or more. When the average particle size is 0.5 mm or more (step S2: Yes), the process proceeds to step S3. On the other hand, if the average particle size is less than 0.5 mm (step S2: No), the particle size is too small and difficult to sort by various physical sorting described later, so the process proceeds to step S24, and the final Specifically, separation and recovery are performed using a cement manufacturing process such as a chlorine bypass system for removing chlorine in the exhaust gas described later.

  Next, in step S3, the necessity of a heating process is determined based on the measurement results of the chemical composition and physical properties in step S1.

  When the waste does not contain metallic aluminum and contains a metal other than metallic aluminum and an organic substance, a heating process is required (step S3: Yes), and in the next step S4, 650 ° C. or more and 1000 ° C. or less. Heat with. This facilitates the separation of the metal by burning the organic matter.

  Moreover, when a waste contains metal aluminum and an organic substance, a heating process is required (step S3: Yes), and it heats at 250 degreeC or more and less than 650 degreeC in following step S4. This prevents melting of the metal aluminum and preserves the amount of heat of the organic material so that it can be reused as a fuel, while making the organic material embrittled and easily separated from the metal.

  Moreover, when it does not correspond to what performs a heating process of 250 degreeC or more and 1000 degrees C or less, and is what aggregates, a heating process is required (step S3: Yes), and in the next step S4, it is 100. Heat at a temperature not lower than 250C and lower than 250C.

  For example, incineration main ash of municipal waste is wet ash containing a lot of moisture, and may contain a high moisture of 15% to 35%. Wastes containing high moisture such as wet ash may be agglomerated and coarsened due to vibrations in the processing apparatus for performing each processing step or dropping during movement between the apparatuses. In addition to clogging in the processing apparatus, the coarsened waste becomes difficult to be sorted with a predetermined particle size and specific gravity in each processing step, which may cause a reduction in sorting efficiency.

  Therefore, in the waste recycling method according to the present invention, waste that contains moisture and may be aggregated is dried by heating to prevent agglomeration in a subsequent treatment step. In addition, about the waste which may be agglomerated, you may add the modifier for preventing agglomeration instead of drying.

  Moreover, when it does not correspond to the said heating, a heating process is unnecessary (step S3: No).

  Next, the particle size of the waste is adjusted (step S5). By adjusting the particle size, the maximum particle size of the waste is adjusted to 5 mm to 30 mm. The particle size is adjusted by crushing with a jaw crusher or impact crusher, or by sieving. The proportion of particles having a particle size range of 0.5 to 5 mm is preferably 60% by weight. By adjusting the particle size, the subsequent eddy current sorting step (steps S13 and S18), the dry specific gravity sorting step (steps S16 and S22), and the like can be performed efficiently.

  Next, based on the measurement result of the chemical composition in step S1, it is determined whether or not a magnetic selection process is necessary (step S6). When the waste contains a metal having a magnetic force, a magnetic force sorting step is necessary (step S6: Yes), and a magnetic force sorting step by a magnetic force sorter is performed (step S7). On the other hand, when the waste does not contain a metal having a magnetic force, the magnetic force sorting step is unnecessary (step S7: No), and the process proceeds to step S9.

  Next, the sorting by the magnetic sorting process is performed based on whether or not it is a magnetic material (step S8). About a magnetic substance (step S8: Yes), iron is mainly contained and this is collect | recovered. On the other hand, with respect to the non-magnetic material (step S8: No), wind sorting is performed using a wind sorter (step S9).

  The wind power selection process is a processing process that is performed based on the size of the floating speed that varies depending on the shape and specific gravity of the waste. Wastes with large particles and large specific gravity, such as metals, tend to have a high floating speed. On the other hand, wastes with small particles and small specific gravity, such as dust, tend to have low floating speed.

  Next, it sorts about what was sorted by a wind power sort process (Step S10). For a waste having a high floating speed (step S10: Yes), it is confirmed whether or not it contains any of metal aluminum, copper, and a noble metal (step S11). On the other hand, for the waste having a low floating speed (step S10: No), the process proceeds to step S24 because organic substances are mainly used.

  When the waste having a high floating speed contains any of metallic aluminum, copper, and noble metal (step S11: Yes), it is determined whether or not an eddy current sorting process is required at less than 4000 rpm (step S12). . On the other hand, if none of metallic aluminum, copper, or noble metal is contained (step S11: No), the process proceeds to step S24 because the inorganic substance is the main component.

  The necessity determination of the eddy current selection process performed at less than 4000 rpm is performed based on the presence or absence of metallic aluminum which is clarified by measuring the chemical composition in step S1.

  When the waste contains metallic aluminum, eddy current sorting is necessary for sorting the metallic aluminum (Step S12: Yes), and eddy current sorting is performed at less than 4000 rpm by the eddy current sorting machine (Step S12). S13).

  In the eddy current selection, the repulsive force of the conductor differs depending on the number of rotations. When the number of rotations is large, a conductor with a small particle size can be selected. This is effective for selecting conductors with large diameters. Therefore, in the waste recycling method according to the present invention, an eddy current selection process using two rotational speeds of less than 4000 rpm (step S13) and 4000 rpm or more (step S18) is used, from the waste to large metal aluminum, Medium and small metal aluminum can be selected.

  On the other hand, when the waste does not contain metallic aluminum, eddy current selection performed at less than 4000 rpm is unnecessary (step S12: No), and the process proceeds to step S15.

  After the eddy current selection process performed at less than 4000 rpm, the selected metal aluminum is refined (step S14: Yes).

  On the other hand, the residue other than metallic aluminum (step S14: No) is determined based on the measurement result of the chemical composition in step S1 whether or not noble metal or copper is contained (step S15).

  When noble metal or copper is contained (step S15: Yes), the dry specific gravity sorting process 1 is performed (step S16). On the other hand, when no precious metal or copper is contained (step S15: No), the process proceeds to step S18.

  The dry specific gravity sorting step 1 is performed using an air table. And what was processed by the dry specific gravity sorting process 1 is sorted into a heavy product and a light product (step S17). The heavy product (step S17: Yes) contains valuable metals such as copper in addition to the noble metals. Such heavy products proceed to the necessity determination (step S18) of the eddy current selection process performed at 4000 rpm or higher. On the other hand, the light product (step S17: No) proceeds to step S24.

  The necessity determination of the eddy current selection process performed at 4000 rpm or more (step S18) is performed based on whether the waste contains metallic aluminum. In the case where metallic aluminum is contained in the waste according to the measurement result of the chemical composition in step S1, medium and small metallic aluminum remain in the waste in the step S18.

  If metallic aluminum is contained, an eddy current selection process is necessary (step S18: Yes), and the eddy current selection process is performed at 4000 rpm or more (step S19). On the other hand, when metallic aluminum is not contained, the said eddy current selection process is unnecessary (step S18: No), and since it contains a noble metal, it is set as a smelting raw material.

  After the eddy current sorting step performed at 4000 rpm or higher, the sorted waste is confirmed (step S20). Of the sorted waste, aluminum is refined (step S20: Yes).

  On the other hand, for residues other than metal aluminum (step S20: No), the presence or absence of noble metal or copper is determined based on the measurement result of the chemical composition in step S1 (step S21). If noble metal or copper is contained (step S21: Yes), the process proceeds to the dry specific gravity sorting step 2. On the other hand, if no precious metal or copper is contained (step S21: No), the process proceeds to step S24.

  Next, it is confirmed whether or not the waste sorted in the dry specific gravity sorting step 2 is a heavy product (step S23). The heavy product (step S23: Yes) is used as a refining raw material because it has high grades of noble metals and copper. On the other hand, if it is a light product, it contains an inorganic substance or an organic substance, and the process proceeds to step S24.

  Whether or not the water washing process is necessary (step S24) is determined based on the chlorine content in the waste, which is known from the measurement of the chemical composition in step S1. If the waste contains chlorine, it is determined that the water washing step is necessary (step S24: Yes). On the other hand, when it does not contain chlorine, it is judged that the water washing process is unnecessary (step S24: No), and the process proceeds to step S26. The chlorine content, which is the basis for determining whether or not the washing process is necessary, is 0.5% when used as a raw material for cement, although it depends on the application. Also, depending on the amount of metal recovered, the chlorine concentration of the object to be washed may be higher than expected, so the chlorine content in the standard waste can be corrected by the metal content in the waste. You may determine the necessity of a water-washing process by measuring the density | concentration of a target object.

  In the water washing step (step S25), industrial water (industrial water) is added to the waste, mixed and stirred to form a slurry, and then dehydrated to remove water-soluble chlorine from the waste. The desalted cake generated after dehydration is dried or mixed with other raw materials as necessary, and then charged into a cement kiln (step S26) and recycled as a cement raw fuel. Moreover, since it can be predicted in advance whether the product contains a large amount of organic matter depending on the composition of the waste to be treated and the production process, the product containing a large amount of organic matter is used as a fuel.

  Although the above has shown the form for implementing this invention with the flowchart in order of a process, the necessity of each process and each process are based on the result of measuring the chemical composition and physical property of a waste (step S1). The use of the product from can be determined and processed. Specifically, according to Table 1 that summarizes the above-described judgment, necessary steps can be performed, and the use of the product obtained from each step can be estimated.

  Here, as virtual waste, an ASR having an average particle size of 2 cm, a maximum particle size of 5 cm, mainly organic matter, containing iron, metal aluminum and copper as metals, and having a chlorine content of 0.6% is processed. And

  Since ASR contains two kinds of metals and organic substances, it is an object of the present invention. Moreover, since the average particle diameter is 0.5 mm or more, the necessity of all processes is examined.

  First, ASR is heated at 250 to 650 ° C. because it contains metallic aluminum and organic matter.

  Next, since ASR has an average particle diameter of 2 cm but a maximum particle diameter of 5 cm, coarse particles are to be crushed.

  Next, since ASR contains iron which is a metal having magnetic force, magnetic force selection is performed. Since it is clear that the magnetic substance obtained here is iron, it is used as an iron-making raw material.

  Next, since wind selection is essential, it shall be performed. Since it is clear that the wind sorting dust obtained here is mainly composed of organic matter, it is assumed to be cement fuel.

  The product that is not wind sorting dust shall then be screened for eddy currents below 4000 rpm because ASR contains metallic aluminum. Since it is clear that the eddy current product obtained here contains a large amount of coarse metal aluminum, it is used as a refining raw material.

  Next, a product that is not an eddy current product is subjected to dry specific gravity sorting 1 because ASR contains copper. Since it is clear that the light products (including cyclodust) obtained here are mainly organic substances, cement fuel is used.

  Next, heavy products that are not light products are subjected to eddy current selection at 4000 rpm or more because ASR contains metallic aluminum. Since the eddy current product obtained here is clear to contain a large amount of medium and fine metal aluminum, it is used as a refining raw material.

  Next, a product that is not an eddy current product is subjected to dry specific gravity sorting 2 because ASR contains metallic aluminum and copper. Since the heavy product (including cyclodust) obtained here clearly contains a large amount of copper, it is used as a refining raw material. On the other hand, since it is clear that the light product obtained here contains a lot of inorganic substances (glass) and organic substances, it is used as cement fuel.

  Finally, the product used as cement fuel is washed with water because the chlorine content of ASR is 0.6%.

  And it processes in the process determined according to the chemical composition and physical property of the waste in this way.

  Further, as the virtual waste, the earth and sand having an average particle diameter of 5 cm, mainly composed of inorganic substances without being aggregated, containing noble metals as metals, and having a chlorine content of 0.1% are treated.

  Since earth and sand contain two types of metals and inorganic substances, they are the subject of the present invention. Moreover, since the average particle diameter is 0.5 mm or more, the necessity of all processes is examined.

  First of all, earth and sand contain metal but no organic matter and do not aggregate, so heating is unnecessary.

  Next, since the average is 5 cm, coarse particles are crushed. However, if the coarse particles clearly do not contain a noble metal, the coarse particles may be simply removed.

  Next, since the earth and sand do not contain a metal having a magnetic force, magnetic separation is not necessary.

  Next, since wind selection is essential, it shall be performed. Since it is clear that the wind-powered dust obtained here is mainly composed of inorganic substances, it is used as a cement raw material.

  The products that are not wind sorting dust then do not require eddy current sorting below 4000 rpm because the earth and sand do not contain metallic aluminum.

  Next, since the earth and sand contain precious metals, dry specific gravity sorting 1 is performed. Since it is clear that the light products (including cyclodust) obtained here are mainly composed of inorganic substances, they are used as cement raw materials.

  Next, although it is a heavy product that is not a light product, since the earth and sand do not contain metallic aluminum, eddy current sorting at 4000 rpm or higher and dry specific gravity sorting 2 are unnecessary. Therefore, it is clear that heavy products contain a large amount of precious metals, so they are used as refining raw materials.

  Finally, the product used as a cement raw material does not need to be washed with water because the chlorine content of the earth and sand is 0.1%.

  And it processes in the process determined according to the chemical composition and physical property of the waste in this way.

  Furthermore, as a virtual waste, a mixed waste having an average particle size of 1 cm, a maximum particle size of 2 cm, mainly organic and inorganic materials, containing iron and metal aluminum as metals, and a chlorine content of 1.0% is treated. Shall.

  Since mixed waste contains three types of metals, organic substances, and inorganic substances, it is an object of the present invention. In addition, since the average particle size is 0.5 mm or more, the necessity of all processes is examined.

  First, since mixed waste contains metallic aluminum and organic matter, it shall be heated at 250-650 degreeC.

  Next, since the average particle size is 1 cm but the maximum particle size is 2 cm, the crushing process is not necessary.

  Next, the mixed waste contains iron, which is a metal having magnetic force, so that magnetic separation is performed. Since it is clear that the magnetic substance obtained here is iron, it is used as an iron-making raw material.

  Next, since wind selection is essential, it shall be performed. The wind-sorted dust obtained here is assumed to be cement fuel because it is clear that organic matter is the main component.

  The product that is not wind sorting dust shall then be subjected to eddy current sorting below 4000 rpm because the mixed waste contains metallic aluminum. Since it is clear that the eddy current product obtained here contains a large amount of coarse metal aluminum, it is used as a refining raw material.

  Next, products that are not eddy current products are not subjected to dry specific gravity sorting 1 because the mixed waste does not contain precious metals and copper.

  Next, since the mixed waste contains metallic aluminum, eddy current selection at 4000 rpm or higher is performed. Since the eddy current product obtained here is clear to contain a large amount of medium and fine metal aluminum, it is used as a refining raw material.

  Next, the product that is not an eddy current product does not need the dry specific gravity sorting 2 because the mixed waste does not contain precious metal or copper. Therefore, it is clear that products that are not eddy current products are mainly composed of inorganic substances, and are therefore used as cement raw materials.

  Finally, the cement fuel and the cement raw material have a chlorine content of 1.0% in the mixed waste, and are used by separately washing with water for fuel and raw material.

  And it processes in the process determined according to the chemical composition and physical property of the waste in this way.

  According to the waste recycling method described above, it is possible to select an appropriate treatment process without trial and error even for mixed waste with no track record, and to improve the recycling rate of mixed waste. .

  In order to improve the recovery rate of valuable metals such as precious metals, a step of recovering the metal volatilized in the exhaust gas generated from the waste put into the cement kiln may be added. For example, by providing a chlorine bypass system that removes chlorine in exhaust gas, collecting dust introduced into the chlorine bypass system and performing a water washing process or a flotation process, the noble metal can be concentrated and recovered. .

Claims (10)

Measure the chemical composition of the waste and the physical properties including the particle size of the waste,
Based on the measured chemical composition and physical properties, predetermined processing steps including heating step, particle size adjustment step, magnetic force selection step, wind force selection step, eddy current selection step, dry specific gravity selection step and water washing step A method for recycling waste, wherein a process to be performed is selected from a group.   2. The waste recycling method according to claim 1, wherein the particle size adjustment step and the wind force selection step in the processing step group are essential steps.   The waste recycling method according to claim 1 or 2, wherein the particle size adjusting step sets the maximum particle size of the waste to 5 mm or more and 30 mm or less.   When the waste does not contain metallic aluminum and contains a metal other than metallic aluminum and an organic substance, the heating step is performed at 650 ° C or higher and 1000 ° C or lower. Recycling method of the listed waste.   4. The waste recycling method according to claim 1, wherein the heating step is performed at 250 ° C. or higher and lower than 650 ° C. when the waste contains metallic aluminum and organic matter.   The method according to claim 1, wherein the heating step is performed at 100 ° C or more and less than 250 ° C when it does not correspond to the heating step at 250 ° C or more and 1000 ° C or less and is to be agglomerated. The waste recycling method according to 2 or 3.   The waste recycling method according to any one of claims 1 to 6, wherein when the waste contains a metal having a magnetic force, the magnetic force sorting step is performed.   The waste recycling method according to any one of claims 1 to 7, wherein when the waste contains metallic aluminum, the eddy current sorting step is performed.   The waste recycling method according to any one of claims 1 to 8, wherein when the waste contains a noble metal and / or copper, the dry specific gravity sorting step is performed.   The waste recycling method according to any one of claims 1 to 9, wherein when the waste contains chlorine, the water washing step is performed.

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