Polyurethane waste recycling device and method

Abstract

The invention provides a polyurethane waste recycling device and method, the device comprises a hydrolysis furnace, a reduction tower and an absorption box, and the hydrolysis furnace is used for hydrolyzing polyurethane waste. And the reduction tower is connected with the hydrolysis furnace so as to reduce nitrogen-containing organic matters in the mixed gas discharged by the hydrolysis furnace. The absorption box is connected with the reduction tower so as to absorb ammonia gas in mixed gas discharged by the reduction tower to form ammonia water, a gas outlet of the absorption box is connected with the gas storage tank, a liquid outlet of the absorption box is connected with the spray gun, and a nozzle of the spray gun is connected to the upper portion of the flue catalytic layer. The formed ammonia water is used as a denitration agent to be sprayed to the upper part of a flue catalytic layer for denitration purification of the flue gas. According to the method, high-level resource utilization of the polyurethane waste is achieved, through chemical reaction treatment, the nitrogen component of the polyurethane waste is converted into ammonia water to be used as a denitration agent, and organic components are converted into combustible gas to be separated and stored.

Description

Technical Field

[0001] The present invention relates to the technical field of resource recycling, and in particular to a polyurethane waste recycling device and method. Background Art

[0002] There are three main methods for recycling polyurethane waste: physical, chemical, and energy. Physical recycling is the most widely used and convenient method. This method involves directly reusing the waste plastic by changing its physical form without destroying the chemical structure or altering its basic composition. Physical recycling of polyurethane waste offers high production efficiency, simple operation, and minimal secondary pollution. However, the product performance is poor, requiring only downgraded recycling, resulting in low economic returns.

[0003] Currently, there is no most effective and high-value solution for the recycling of polyurethane waste. Therefore, it is necessary to develop new resource utilization technologies for it. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, the embodiments of the present invention provide a polyurethane waste recycling device and method, which can achieve high-level resource utilization of polyurethane waste.

[0005] In one aspect, an embodiment of the present invention proposes a polyurethane waste recycling device, comprising: a hydrolysis furnace, a reduction tower and an absorption box. The hydrolysis furnace has a hydrolysis chamber and a feed port, an air inlet and an air outlet connected to the hydrolysis chamber. The feed port of the hydrolysis chamber is connected to a polyurethane silo. The air inlet of the hydrolysis chamber is suitable for conveying steam into the hydrolysis chamber. The hydrolysis chamber is suitable for hydrolyzing polyurethane waste.

[0006] The reduction tower has an air inlet and an air outlet. The air inlet of the reduction tower is connected to the air outlet of the hydrolysis furnace to reduce nitrogen-containing organic matter in the mixed gas discharged from the hydrolysis furnace.

[0007] The absorption box has an air inlet, an air outlet and a liquid outlet. The air inlet of the absorption box is connected to the air outlet of the reduction tower to absorb the ammonia in the mixed gas discharged from the reduction tower to form ammonia water. The air outlet of the absorption box is connected to the gas storage tank, and the liquid outlet of the absorption box is connected to the spray gun. The nozzle of the spray gun is connected to the top of the flue catalytic layer to spray the formed ammonia water as a denitrification agent into the top of the flue catalytic layer to denitrify and purify the flue gas.

[0008] In some embodiments, the reduction tower includes a first reduction tower and a second reduction tower, and the first reduction tower and the second reduction tower are connected in parallel between the hydrolysis furnace and the absorption box.

[0009] In some embodiments, pressure gauges are respectively connected to the first reduction tower and the second reduction tower to monitor the air pressure in the first reduction tower and the second reduction tower, and control valves are respectively connected to the connecting pipelines between the hydrolysis furnace and the air inlet of the first reduction tower and the air inlet of the second reduction tower.

[0010] In some embodiments, the polyurethane waste recycling device further includes a clean water tank and a heater, the water outlet of the clean water tank is connected to the heater to heat water to generate steam, and the steam outlet of the heater is connected to the air inlet of the hydrolysis furnace.

[0011] In some embodiments, a pressure pump is connected to the connecting pipeline between the liquid outlet of the absorption box and the spray gun.

[0012] In some embodiments, a liquid level sensor for monitoring the liquid level of ammonia water is provided in the absorption box, and the liquid outlet of the absorption box is located at the bottom of the absorption box.

[0013] Another embodiment of the present invention provides a polyurethane waste recycling method, which utilizes the above-mentioned polyurethane waste recycling device and includes the following steps:

[0014] The polyurethane waste is sent into the hydrolysis furnace, and the desalted water in the clean water tank is heated by a heater to generate steam, which is sprayed into the hydrolysis furnace to undergo a hydrolysis reaction with the polyurethane waste to obtain a mixed gas with CO, CxHy, NH3, and CH3NH2 as the main components.

[0015] The mixed gas enters the reduction tower to reduce nitrogen-containing organic matter into NH3 and C x H y , NH3, C x H y And the gas that does not participate in the reaction enters the absorption box.

[0016] The absorption box absorbs NH3 to form ammonia water, while other gases are insoluble and separated and then stored in the gas tank.

[0017] The ammonia water in the absorption box is passed into the spray gun and sprayed into the top of the flue catalytic layer by the spray gun, acting as a denitrification agent to denitrify and purify the flue gas.

[0018] In some embodiments, the reduction tower includes a first reduction tower and a second reduction tower connected in parallel. The mixed gas discharged from the hydrolysis furnace enters the first reduction tower and the second reduction tower in batches. The pressure in the first reduction tower and the second reduction tower is monitored. When the pressure of one of the reduction towers reaches a limit value, the mixed gas is stopped from being introduced into the reduction tower.

[0019] In some embodiments, the temperature of the steam generated by the heater is above 260°C, and the temperature in the hydrolysis furnace is maintained above 205°C.

[0020] In some embodiments, the ratio of the mass of the polyurethane waste to the volume of the steam in the hydrolysis furnace is 1:1.2-1.5. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings.

[0022] in:

[0023] Figure 1 Schematic diagram of the structure of a polyurethane waste recycling device in an embodiment of the present invention;

[0024] Reference numerals:

[0025] 1. Clean water tank; 2. Heater; 3. Hydrolysis furnace; 4. Polyurethane silo; 5. First reduction tower; 6. Second reduction tower; 7. Gas storage tank; 8. Absorption box; 9. Pressure pump; 10. Spray gun; 11. Flue catalytic layer. DETAILED DESCRIPTION

[0026] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0027] The following describes a polyurethane waste recycling device and method according to an embodiment of the present invention with reference to the accompanying drawings.

[0028] like Figure 1 As shown, an embodiment of one aspect of the present invention proposes a polyurethane waste recycling device, including: a hydrolysis furnace 3, a reduction tower and an absorption box 8. The hydrolysis furnace 3 has a hydrolysis chamber and a feed port, an air inlet and an air outlet connected to the hydrolysis chamber. The feed port of the hydrolysis chamber is connected to the polyurethane silo 4. The air inlet of the hydrolysis chamber is suitable for conveying steam into the hydrolysis chamber. The hydrolysis chamber is suitable for hydrolyzing polyurethane waste.

[0029] The reduction tower has an air inlet and an air outlet. The air inlet of the reduction tower is connected to the air outlet of the hydrolysis furnace 3 to reduce nitrogen-containing organic matter in the mixed gas discharged from the hydrolysis furnace 3.

[0030] The absorption box 8 has an air inlet, an air outlet and a liquid outlet. The air inlet of the absorption box 8 is connected to the air outlet of the reduction tower to absorb the ammonia in the mixed gas discharged from the reduction tower to form ammonia water. The air outlet of the absorption box 8 is connected to the gas storage tank 7, and the liquid outlet of the absorption box 8 is connected to the spray gun 10. The nozzle of the spray gun 10 is connected to the top of the flue catalytic layer 11 to spray the formed ammonia water as a denitrification agent into the top of the flue catalytic layer 11 to denitrify the flue gas.

[0031] The embodiment of the present invention achieves high-level resource utilization of polyurethane waste by providing a hydrolysis furnace 3, a reduction tower and an absorption box 8. Through chemical reaction treatment, its nitrogen component is converted into ammonia water for use as a denitrification agent, and the organic component is converted into combustible gas for separation and storage.

[0032] Furthermore, the nozzle of the spray gun 10 is arranged on the upper smoke wall of the flue catalytic layer 11, with the nozzle facing inward.

[0033] In some embodiments, the reduction tower includes a first reduction tower 5 and a second reduction tower 6 , and the first reduction tower 5 and the second reduction tower 6 are connected in parallel between the hydrolysis furnace 3 and the absorption box 8 .

[0034] For situations with a large processing volume, the mixed gas can be first introduced into one of the reduction towers for reduction. When the amount introduced into the reduction tower reaches a limit value, the mixed gas can be introduced into another reduction tower to achieve continuous operation.

[0035] In some embodiments, pressure gauges are respectively connected to the first reduction tower 5 and the second reduction tower 6 to monitor the air pressure in the first reduction tower 5 and the second reduction tower 6, and control valves are respectively connected to the connecting pipelines of the hydrolysis furnace 3 and the air inlet of the first reduction tower 5 and the air inlet of the second reduction tower 6.

[0036] When the pressure in one of the reduction towers reaches the limit value, it means that the amount of gas introduced into the reduction tower is sufficient and no more gas can be introduced. At this time, the control valve of the reduction tower is closed, and the control valve of the other reduction tower is opened to allow the mixed gas to be introduced into the other reduction tower.

[0037] In some embodiments, the polyurethane waste recycling device also includes a clean water tank 1 and a heater 2. The water outlet of the clean water tank 1 is connected to the heater 2 to heat water to generate steam. The steam outlet of the heater 2 is connected to the air inlet of the hydrolysis furnace 3.

[0038] By arranging the clean water tank 1 and the heater 2, a source of steam is provided, and the temperature of the steam can be controlled by the heater 2 so that the temperature of the steam reaches the temperature required by the reduction furnace.

[0039] In some embodiments, a pressure pump 9 is connected to the connecting pipeline between the liquid outlet of the absorption box 8 and the spray gun 10 to provide high pressure for the injection of ammonia water.

[0040] In some embodiments, a liquid level sensor for monitoring the liquid level of the ammonia solution is provided in the absorption box 8 , and the liquid outlet of the absorption box 8 is located at the bottom of the absorption box 8 .

[0041] By providing a liquid level sensor, the liquid level of the ammonia solution in the absorption box 8 can be monitored. When the liquid level of the ammonia solution drops to a limit value, it is not appropriate to continue to pass the ammonia solution into the spray gun 10. At this time, the spray gun 10 or the pressure pump 9 should be turned off. This is because the absorption box 8 also contains other combustible gases that can be used as fuel. Since the density of the combustible gases is lighter than that of the ammonia solution, they will float on the ammonia solution. If the ammonia solution is continued to be passed into the spray gun 10 at this time, it is easy for the combustible gases to be passed into the spray gun 10 and then injected into the flue. On the one hand, this will lead to waste of resources due to discharge into the atmosphere. On the other hand, due to the high temperature in the flue, it may cause the combustible gases to burn or explode.

[0042] It should be noted that it is not suitable to connect an air pump between the absorption box 8 and the gas storage tank 7. This is because the ammonia in the ammonia water is unstable and it is easy to extract the ammonia from the ammonia water, which will cause the ammonia to contaminate the recovered combustible gas and also reduce the recovery amount of ammonia water.

[0043] Another embodiment of the present invention provides a polyurethane waste recycling method, which utilizes the above-mentioned polyurethane waste recycling device and includes the following steps:

[0044] The polyurethane waste is fed into the hydrolysis furnace 3, and the desalted water in the clean water tank 1 is heated by the heater 2 to generate steam, which is sprayed into the hydrolysis furnace 3 to undergo a hydrolysis reaction with the polyurethane waste to obtain a mixed gas with CO, CxHy, NH3, and CH3NH2 as the main components.

[0045] The mixed gas enters the reduction tower to reduce nitrogen-containing organic matter such as CH3NH2 into NH3 and C x H y , NH3, C x H y And all the gases that do not participate in the reaction enter the absorption box 8.

[0046] The absorption box 8 absorbs NH3 to form ammonia water, and other gases are insoluble and separated and then enter the gas storage tank 7 for storage.

[0047] The ammonia solution in the absorption box 8 is introduced into the spray gun 10 and sprayed into the upper part of the flue catalytic layer 11 by the spray gun 10 to act as a denitrification agent to denitrify and purify the flue gas.

[0048] The method of the embodiment of the present invention achieves a high level of resource utilization of polyurethane waste. Through chemical reaction treatment, the nitrogen component is converted into ammonia water for use as a denitrification agent, and the organic component is converted into combustible gas for separation and storage.

[0049] In some embodiments, the reduction tower includes a first reduction tower 5 and a second reduction tower 6 connected in parallel. The mixed gas discharged from the hydrolysis furnace 3 enters the first reduction tower 5 and the second reduction tower 6 in batches. The pressure in the first reduction tower 5 and the second reduction tower 6 is monitored. When the pressure of one of the reduction towers reaches a limit value, the mixed gas is stopped from being introduced into the reduction tower.

[0050] In some embodiments, the temperature of the steam generated by the heater 2 is above 260° C., and the temperature in the hydrolysis furnace 3 is maintained above 205° C. This can reach the temperature required for reducing nitrogen-containing organic matter in the reduction tower, making the reduction reaction more complete and increasing the recovery of ammonia.

[0051] In some embodiments, the ratio of the mass of the polyurethane waste to the volume of the steam in the hydrolysis furnace 3 is 1:1.2-1.5. Within this dosage range, the polyurethane waste can be fully hydrolyzed.

[0052] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0053] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0054] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0055] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0056] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0057] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A polyurethane waste recycling device, characterized in that: include: A hydrolysis furnace, comprising a hydrolysis chamber and a feed port, an air inlet, and an air outlet connected to the hydrolysis chamber, wherein the feed port of the hydrolysis chamber is connected to a polyurethane silo, the air inlet of the hydrolysis chamber is adapted to transport steam into the hydrolysis chamber, and the hydrolysis chamber is adapted to hydrolyze polyurethane waste; A reduction tower, the reduction tower having an air inlet and an air outlet, the air inlet of the reduction tower being connected to the air outlet of the hydrolysis furnace to reduce nitrogen-containing organic matter in the mixed gas discharged from the hydrolysis furnace; An absorption box having an air inlet, an air outlet and a liquid outlet. The air inlet of the absorption box is connected to the air outlet of the reduction tower to absorb the ammonia in the mixed gas discharged from the reduction tower to form ammonia water. The air outlet of the absorption box is connected to a gas storage tank. The liquid outlet of the absorption box is connected to a spray gun. The nozzle of the spray gun is connected to the top of the flue catalytic layer to spray the formed ammonia water as a denitrification agent into the top of the flue catalytic layer to denitrify the flue gas.

2. The polyurethane waste recycling device according to claim 1, characterized in that: The reduction tower includes a first reduction tower and a second reduction tower, and the first reduction tower and the second reduction tower are connected in parallel between the hydrolysis furnace and the absorption box.

3. The polyurethane waste recycling device according to claim 2, characterized in that: Pressure gauges are respectively connected to the first reduction tower and the second reduction tower to monitor the air pressure in the first reduction tower and the second reduction tower, and control valves are respectively connected to the connecting pipelines of the hydrolysis furnace and the air inlet of the first reduction tower and the air inlet of the second reduction tower.

4. The polyurethane waste recycling device according to claim 1, characterized in that: It also includes a clean water tank and a heater. The water outlet of the clean water tank is connected to the heater to heat water to generate steam. The steam outlet of the heater is connected to the air inlet of the hydrolysis furnace.

5. The polyurethane waste recycling device according to claim 1, characterized in that: A pressure pump is connected to the connecting pipeline between the liquid outlet of the absorption box and the spray gun.

6. The polyurethane waste recycling device according to claim 1, characterized in that: A liquid level sensor for monitoring the liquid level of ammonia water is provided in the absorption box, and the liquid outlet of the absorption box is located at the bottom of the absorption box.

7. A method for recycling polyurethane waste, characterized in that: The polyurethane waste recycling device according to any one of claims 1 to 6 comprises the following steps: The polyurethane waste is fed into the hydrolysis furnace, and the desalted water in the clean water tank is heated by a heater to generate steam, which is then sprayed into the hydrolysis furnace to undergo a hydrolysis reaction with the polyurethane waste to produce a mixed gas with CO, CxHy, NH3, and CH3NH2 as the main components; The mixed gas enters the reduction tower to reduce nitrogen-containing organic matter into NH3 and C x H y , NH3, C x H y And the gas that does not participate in the reaction enters the absorption box; The absorption box absorbs NH3 to form ammonia water, while other gases are insoluble and separated and then stored in the gas storage tank; The ammonia water in the absorption box is introduced into the spray gun and sprayed into the upper part of the flue catalytic layer by the spray gun to perform denitration and purification of the flue gas as a denitrification agent.

8. The polyurethane waste recycling method according to claim 7, characterized in that: The reduction tower includes a first reduction tower and a second reduction tower connected in parallel. The mixed gas discharged from the hydrolysis furnace enters the first reduction tower and the second reduction tower in batches. The pressure in the first reduction tower and the second reduction tower is monitored. When the pressure of one of the reduction towers reaches a limit value, the mixed gas is stopped from being introduced into the reduction tower.

9. The polyurethane waste recycling method according to claim 7, characterized in that: The temperature of the steam generated by the heater is above 260°C, and the temperature in the hydrolysis furnace is maintained above 205°C.

10. The polyurethane waste recycling method according to claim 7, characterized in that: In the hydrolysis furnace, the ratio of the mass of the polyurethane waste to the volume of the steam is 1:1.2-1.5.

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