System and method for producing carbon black from scrap tires using pyrolysis

Abstract

The method for producing carbon black according to the present invention includes the steps of heating and pyrolyzing waste tires, separating char from foreign matter containing iron from the pyrolyzed material, pulverizing the char into a fine or fine form to form carbon black, pelletizing the carbon black, cooling and drying the pelletized carbon black, and packaging the pelletized carbon black, wherein the pyrolysis step includes a first pyrolysis step of heating the waste tires and a second pyrolysis step of heating the char and iron from the primary pyrolyzed material, and the heating temperature of the second pyrolysis step is higher than the heating temperature of the first pyrolysis step.

Description

[Technical field]

[0001] The present invention relates to a system and method for producing carbon black from waste tires to obtain better performance carbon black. [Background technology]

[0002] Organic polymer waste such as waste tires and waste plastics are generated as a large amount of waste both in Japan and overseas. In particular, about 1.5 billion waste tires are generated worldwide every year, which is equivalent to about 15 million tons in weight. In Japan, about 380,000 tons of waste tires were generated in 2021. The disposal of these wastes is divided into landfilling, incineration, and recycling. Landfilling is becoming less important among waste disposal methods because waste tires and waste plastics are not easily decayed, and there is a problem that suitable landfill sites must be developed continuously. The problem of soil pollution is also important. On the other hand, incineration has the advantage that the volume can be minimized in a short time and the heat generated during incineration can be used. However, the emission of air pollutants such as dioxins generated during incineration has become a problem, and the development of alternative technologies is required.

[0003] Therefore, recycling of waste tires is expected to be an alternative that can reduce the amount of waste generated and solve the problem of environmental pollution that can occur due to landfilling and incineration.

[0004] Among the methods for recycling waste tires, the most commonly used method is pyrolysis, which involves thermally decomposing organic waste in an oxygen-free environment at temperatures between 500 and 800°C.

[0005] In this regard, Published Japanese Patent Application No. 10-2019-0084713 discloses a system and method for purifying char and producing carbon black via pyrolysis of waste tires, but the patent does not specifically disclose the specific parameters or manner of such pyrolysis. Summary of the Invention [Problem to be solved by the invention]

[0006] It is an object of the present invention to provide a carbon black production system and method for obtaining carbon black of superior quality to existing products. [Means for solving the problem]

[0007] A method for producing carbon black according to the present invention includes the steps of heating and pyrolyzing waste tires, separating char from foreign matter containing iron, pulverizing the char into fine or fine particles to form carbon black, pelletizing the carbon black, cooling and drying the pelletized carbon black, and packaging the pelletized carbon black. The pyrolysis step includes a first pyrolysis step of heating the waste tires and a second pyrolysis step of heating the char and iron from the first pyrolysis. The heating temperature of the second pyrolysis step may be higher than the heating temperature of the first pyrolysis step.

[0008] In one embodiment, the waste tires may be heated at 300 to 450°C in the first pyrolysis step, and the char and iron may be heated at 550 to 700°C in the second pyrolysis step.

[0009] In one embodiment, the step of pulverizing the char to a fine form to form carbon black may include a first pulverization step and a second pulverization step.

[0010] In one embodiment, in the first grinding step, the char is ground by any one of a ring roller mill, an air classifier mill (ACM), and a Raymond mill, and in the second grinding step, the char may be ground by a ring roller mill or an ACM.

[0011] In one embodiment, in the first crushing step, the char may be crushed to a particle size of 80 μm or less, and in the second crushing step, the char may be crushed to a particle size of 10 μm or less.

[0012] The carbon black system according to the present invention includes a supply unit to which waste tires are input, a pyrolysis unit for pyrolyzing the waste tires supplied from the supply unit, in which the waste tires are pyrolyzed into gas, oil, char, and iron, an exhaust unit to which flue gas generated by combustion in the pyrolysis unit is sent, the exhaust unit having a compression unit for compressing the transferred gas, a denitrification unit for removing nitrogen, and a desulfurization unit for removing sulfur from the gas, a condensation unit to which oil vapor decomposed in the pyrolysis unit is sent, the condensation unit being positioned horizontally to the pyrolysis unit and adjacent to the pyrolysis unit, the condensation unit condenses the oil vapor to generate oil, and transfers non-condensed non-condensable gases to the pyrolysis unit for use in combustion, and a sorting unit to which the char decomposed in the pyrolysis unit is sent, the char in the sorting unit being selected from the group consisting of iron, The present invention relates to a waste tire recycling system, and a waste tire recycling method. The waste tire recycling system includes a waste tire recycling unit that can be used for recycling waste tires. The waste tire recycling unit includes a waste tire recycling unit that can be used for recycling waste tires. The waste tire recycling unit includes a waste tire recycling unit that can be used for recycling waste tires. The waste tire recycling unit includes a waste tire recycling unit that can be used for recycling waste tires. The waste tire recycling unit includes a waste tire recycling unit that can be used for recycling waste tires. The waste tire recycling unit includes a waste tire recycling unit that can be used for recycling waste tires.

[0013] In one embodiment, the waste tires may be heated at 300 to 450°C in the first pyrolysis section, and the char and iron may be heated at 550 to 700°C in the second pyrolysis section.

[0014] In one embodiment, the crushing unit may include a primary crushing unit and a secondary crushing unit.

[0015] In one embodiment, in the first grinding section, the char is ground by any one of a ring roller mill, an ACM, and a Raymond mill, and in the second grinding section, the char is ground by a ring roller mill or an ACM.

[0016] In one embodiment, the char may be pulverized to a particle size of 80 μm or less in the first crushing section, and the char may be pulverized to a particle size of 10 μm or less in the second crushing section. Effect of the Invention

[0017] In the carbon black production system and method according to the present invention, pyrolysis is carried out in two stages, at 300 to 450°C for the first stage and 550 to 700°C for the second stage, so that carbon black with excellent quality can be obtained and continuous operation is possible, resulting in improved operating efficiency.

[0018] The carbon black production system and method according to the present invention can produce carbon black with small particle size, excellent quality, and low production costs by crushing the char in two separate steps without using a jet mill. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a diagram showing a system for producing carbon black by pyrolysis of waste tires according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings, in which: FIG. 1 is a block diagram of a semiconductor device according to an embodiment of the present invention;

[0021] Fig. 1 is a diagram showing a system for producing carbon black by pyrolysis of waste tires according to the present invention. As shown in Fig. 1, the system for producing carbon black by pyrolysis of waste tires according to the present invention may include a supply unit 10, a pyrolysis unit 20, an exhaust unit 30, a condensation unit 40, a sorting unit 50, a storage unit 60, a crushing unit 70, a molding unit 80, a drying and cooling unit 90, and a packaging unit 100.

[0022] The supply unit 10 may be a part where waste tires are input. The supply unit 10 may transport the input waste tires via a drag conveyor inside the supply unit 10 and store them in a storage silo. The waste tires stored in the storage silo may be discharged via a discharge conveyor belt and directed to the pyrolysis unit 20.

[0023] The pyrolysis unit 20 may be a unit for pyrolyzing the waste tires supplied from the supply unit 10. The pyrolysis unit 20 may be composed of a primary pyrolysis unit 23 and a secondary pyrolysis unit 26. In the primary pyrolysis unit 23, high-temperature gas generated from a hot air furnace flows into the reactor, and the waste tires can be heated to a high temperature, for example, 300 to 450°C. The reactor is airtight from the outside and operates in an oxygen-free or low-oxygen atmosphere, and nitrogen may be supplied to one end of the reactor to maintain this. The heated waste tires may be decomposed into gas, oil, char, iron, etc.

[0024] Since the primary pyrolysis unit 23 is heated at a lower temperature than the conventional pyrolysis process, the ratio of gas may be lower and the ratio of oil may be higher than the conventional pyrolysis process. For example, if the conventional pyrolysis at a temperature exceeding 500°C contains 15% gas by weight, 40% oil by weight, 35% char by weight, and 10% iron by weight, the pyrolysis process according to the present invention may contain 10% gas by weight, 45% oil by weight, 35% char by volume, and 10% iron by weight. That is, the pyrolysis process according to the present invention may have a higher ratio of oil and a lower ratio of gas than the conventional pyrolysis process. Therefore, the maintenance and management of the process may be easier, and the operation of the process may be continuous, leading to improved operation efficiency.

[0025] Flue gas generated by combustion in the primary pyrolysis unit 23 may be sent to the exhaust unit 30. The exhaust unit 30 may include a compression unit for compressing the transferred gas, a denitrification unit for removing nitrogen from the gas, and a desulfurization unit for removing sulfur from the gas. The exhaust gas discharged through these units may be safer from air pollution.

[0026] The oil vapor decomposed in the first pyrolysis unit 23 may be sent to the condensation unit 40. The condensation unit 40 may be positioned horizontally with the first pyrolysis unit 23 and adjacent to the first pyrolysis unit 23. The condensation unit 40 may condense the oil vapor, transfer the generated oil via an oil pump, and store it in an oil storage tank. Non-condensable gas that is not condensed may be transferred to a gas tank via a transfer fan and stored. Thereafter, the non-condensable gas may be transferred to a hot air furnace of the first pyrolysis unit 23 and used for combustion. Therefore, the process cost may be reduced and the process may be environmentally friendly by recycling the non-condensable gas.

[0027] The char and iron decomposed in the first pyrolysis unit 23 may be sent to the second pyrolysis unit 26 via one or more conveyors. The second pyrolysis unit 26 may be a unit that thermally decomposes the supplied char and iron. In the second pyrolysis unit 26, high-temperature gas generated from a hot blast stove flows into the reactor, and the char and iron can be heated to a high temperature, for example, 550 to 700°C. That is, the heating temperature in the second pyrolysis unit 26 may be higher than the heating temperature in the first pyrolysis unit 23. The reactor is airtight from the outside and operates in an oxygen-free or low-oxygen atmosphere, and nitrogen may be supplied to one end of the reactor to maintain this. The heated char and iron may be decomposed again into gas, oil, char, iron, etc., as in the first pyrolysis unit 23. The gas and oil decomposed in this manner may be sent to the exhaust unit 30 and the condensation unit 40 like the decomposition products of the first pyrolysis unit 23.

[0028] The pyrolysis process according to the present invention can perform not only the first pyrolysis process but also the second pyrolysis process at a higher temperature, resulting in a lower oil content on the surface of the carbon black than that of existing carbon black, leading to excellent carbon black quality and a reduced amount of polycyclic aromatic hydrocarbons (PAHs), which are carcinogenic.

[0029] As a result, the pyrolysis process of the present invention has the advantage of simultaneously producing char with low surface oil content and low PAHs, while producing a low rate of gas and a high rate of oil, and is easy to maintain.

[0030] The charr and iron decomposed in the secondary pyrolysis section 26 may be sent to the sorting section 50 via one or more conveyors. The sorting section 50 may be a section that separates foreign matter, including iron, from the charr. For example, the sorting section 50 may include a primary sorter that vibrates the charr to separate foreign matter, and a secondary sorter that uses magnetic force to separate iron from the charr transferred from the primary sorter.

[0031] The charr may be sent from the sorting unit 50 to the storage unit 60 via one or more conveyors. The storage unit 60 may be a portion where the charr is stored. In the present embodiment, the storage unit 60 is illustrated as including a silo, but is not limited thereto.

[0032] The char may be transferred from the storage unit 60 to the pulverizing unit 70. The pulverizing unit 70 may pulverize the char to be transferred into fine particles or a fractional form to form carbon black. The pulverizing unit 70 may be composed of a primary pulverizing unit 73 and a secondary pulverizing unit 76. In the pulverizing unit 70, the char may be pulverized by a primary pulverizing process in the primary pulverizing unit 73 and a secondary pulverizing process in the secondary pulverizing unit 76. In the primary pulverizing process, the char without particle size distribution may be pulverized to a particle size of 80 μm or less by any one of a ring roller mill, an air classifier mill (ACM), and a Raymond mill, and in the secondary pulverizing process, the char having a particle size of 80 μm or less may be pulverized to a particle size of 10 μm or less by a ring roller mill or an ACM to form carbon black. In one embodiment, in the first crushing step, the char having no particle size distribution can be crushed to a particle size of 80 μm or less using a ring roller mill, and in the second crushing step, the char having a particle size of 80 μm or less can be crushed to a particle size of 10 μm or less using ACM to form carbon black.

[0033] In the conventional grinding process, a ring roller mill is used only once to produce carbon black having a particle size of 80 μm or less. However, this has a larger particle size than the carbon black produced using the system and method of the present invention, which results in poor quality carbon black.

[0034] In addition, in the existing pulverization process, a jet mill may be used to produce carbon black having a particle size of 10 μm or less. However, the volume of the jet mill itself is very large, which requires high equipment costs and consumes a lot of electricity.

[0035] The system and method of the present invention provides the advantage of being able to produce high quality carbon black having a particle size of 10 μm or less without the need for space-consuming and expensive jet mills.

[0036] The formed carbon black may be transferred from the grinding section 70 to the molding section 80. In the molding section 80, the carbon black may be molded into a spherical shape using water as a binder.

[0037] The molding unit 80 may include a pelletizer for pelletizing the carbon black. The pelletizer of the molding unit 80 may contain not only carbon black but also other substances to firmly pack the carbon black into a spherical shape.

[0038] Existing compositions for pelletizing carbon black can contain 95% by weight or more of carbon black, less than 5% by weight of ash, and inorganic additives. In this case, the carbon black may not solidify well and may be difficult to pelletize using only the composition and water. Therefore, existing compositions for pelletizing carbon black have a problem in that other materials such as starch must be included in order to pelletize the carbon black.

[0039] Alternatively, the composition for pelletizing carbon black according to the present invention may contain 75 to 85% by weight of carbon black, 15 to 25% by weight of ash, and inorganic additives. For example, the inorganic additives may be zinc oxide (ZnO), magnesium oxide (MgO), silica (SiO 2 ), zinc sulfide (ZnS), calcium carbonate (CaCo3 The composition for pelletizing carbon black according to the present invention may contain more ash and inorganic additives than existing compositions for pelletizing carbon black, and therefore may solidify better than existing compositions for pelletizing carbon black.

[0040] Meanwhile, the composition for pelletizing carbon black according to the present invention can be well solidified even when mixed only with water without other additives such as starch. On the contrary, the composition for pelletizing carbon black according to the present invention can have a pellet hardness of 80 to 100 even when mixed only with water. In this case, there is an advantage that the pelletized carbon black does not break during storage and transportation. However, there is a disadvantage that the pelletized carbon black cannot be easily broken when a customer uses the carbon black.

[0041] Therefore, a cationic surfactant may be added to the composition for pelletizing carbon black according to the present invention together with water during pelletizing. The cationic surfactant may play a role in preventing the aggregation of carbon black. The cationic surfactant may include amide imidazolinium, stearylamine acetate, lauryl trimethyl ammonium chloride, diamide alkoxylate quaternary ammonium, and diester alkoxylate quaternary ammonium. The amount of water added may be 40 to 50 parts by weight based on 100 parts by weight of carbon black, and the amount of the cationic surfactant added may be 0.1 to 1 part by weight based on 100 parts by weight of carbon black. Even if such a small amount of cationic surfactant is added, the pellet hardness may be sufficiently reduced to 20 to 50.

[0042] The composition for pelletizing carbon black according to the present invention has good agglomeration due to the amount of inorganic additives, and can be less agglomerated by adding a cationic surfactant during pelletizing. Therefore, the pelletized carbon black has the advantage that it does not crumble easily during storage and transportation, and can be easily crushed by a mixer when used by customers.

[0043] The carbon black pelletized in the molding unit 80 may be sent to the drying and cooling unit 90 via a conveyer belt to be dried and cooled. For example, the pelletized carbon black may first be dried by heat in a dryer in the drying and cooling unit 90, and then cooled in a cooler. When the pelletized carbon black is dried in the dryer, water added to the carbon black composition may be removed. For example, 40 to 50 parts by weight of water added to 100 parts by weight of carbon black may be dried to leave less than 1 part by weight.

[0044] In the drying and cooling section 90, the carbon black may be sent to the packaging section 100 via a conveyor belt. The packaging section may package the pelletized carbon black in a preset amount. For example, the packaging section 100 may include a ton bag packaging section and an individual packaging section. In the drying and cooling section 90, the carbon black may be connected to a two-way damper of the packaging section 100, and the carbon black may be selectively transferred to the ton bag packaging section and the individual packaging section via the two-way damper.

[0045] With the above-mentioned configuration, the operation of producing carbon black through the pyrolysis of waste tires is carried out in a continuous and sequential manner through a series of steps that are continued in an optimal order, and as a result, the quality of the pelletized carbon black can be made extremely good.

[0046] Although the technical concept of the present invention has been described above with reference to the accompanying drawings, this is merely an illustrative description of a preferred embodiment of the present invention and is not intended to limit the present invention. In addition, it is obvious that anyone having ordinary knowledge in this technical field can make various modifications and imitation of the present invention within the scope of the technical concept of the present invention.

Claims

1. 1. A method for producing carbon black, comprising the steps of: A step of heating and pyrolyzing the waste tires; Separating the char from the pyrolyzed material from the iron-containing foreign matter; grinding the charr into a fine or finely divided form to form carbon black; pelletizing the carbon black; cooling and drying the pelletized carbon black; packaging the pelletized carbon black; Including, The pyrolyzing step includes: A primary pyrolysis step of heating the waste tires; A secondary pyrolysis step of heating char and iron from the primary pyrolysis material; Including, The heating temperature of the second pyrolysis step is higher than the heating temperature of the first pyrolysis step; A method for producing carbon black.

2. In the first pyrolysis step, the waste tires are heated at 300 to 450°C; In the second pyrolysis step, the char and iron are heated at 550 to 700 ° C.

10. A method for producing the carbon black of claim 1.

3. The step of grinding the char to a fine particle form to form carbon black comprises: A primary grinding step; A secondary grinding step; Including, 10. A method for producing the carbon black of claim 1.

4. In the first grinding step, the char is ground by any one of a ring roller mill, an air classifier mill (ACM), and a Raymond mill; In the second grinding step, the char is ground by a ring roller mill or ACM.

4. A method for producing the carbon black of claim 3.

5. In the first crushing step, the char is crushed to a particle size of 80 μm or less, In the secondary grinding step, the char is ground to a particle size of 10 μm or less. A method for producing the carbon black of claim 3 or 4.

6. 1. A carbon black production system comprising: A supply section where waste tires are input; a pyrolysis unit for pyrolyzing the waste tires supplied from the supply unit, the waste tires being pyrolyzed into gas, oil, char, and iron in the pyrolysis unit; an exhaust section to which flue gas generated by combustion in the pyrolysis section is sent, the exhaust section including a compression section for compressing the transported gas, a denitrification section for removing nitrogen, and a desulfurization section for removing sulfur from the gas; a condensation section to which the oil vapor decomposed in the thermal decomposition section is sent, the condensation section being positioned horizontally to the thermal decomposition section and adjacent to the thermal decomposition section, the condensation section condensing the oil vapor to generate oil, and transferring the non-condensable gas that was not condensed to the thermal decomposition section for use in combustion; A sorting section to which the char decomposed in the pyrolysis section is sent, in which the char is separated from foreign matter containing iron; A storage unit in which the char sent from the sorting unit is stored; A crushing unit to which the charr is transferred from the storage unit, the crushing unit crushing the charr into fine particles or fine particles to form carbon black; a molding section to which the carbon black is sent from the crushing section, the molding section including a pelletizer that pelletizes the carbon black; a cooling and drying section to which the carbon black pelletized in the molding section is transferred and cooled and dried; a packaging section for packaging the pelletized carbon black sent from the cooling and drying section; Equipped with The thermal decomposition section includes: a primary pyrolysis section for heating the waste tires; a secondary pyrolysis section for heating char and iron from the primary pyrolysis material; Equipped with The heating temperature in the secondary pyrolysis section is higher than the heating temperature in the primary pyrolysis section; Carbon black production system.

7. In the primary pyrolysis section, the waste tires are heated at 300 to 450°C, In the secondary pyrolysis section, the char and iron are heated to 550 to 700 ° C.

7. The carbon black production system of claim 6.

8. The crushing unit includes: A primary crushing section; A secondary crushing section; Equipped with 7. The carbon black production system of claim 6.

9. In the primary crushing section, the char is crushed by any one of a ring roller mill, an ACM, and a Raymond mill; In the secondary grinding section, the char is ground by a ring roller mill or an ACM.

9. The carbon black production system of claim 8.

10. In the primary crushing section, the char is crushed to a particle size of 80 μm or less, In the secondary crushing section, the char is crushed to a particle size of 10 μm or less. The carbon black production system according to claim 8 or 9.

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