Solid recovered fuel preparation system and preparation method

Abstract

The present invention relates to the technical field of waste treatment, and provides a solid recovered fuel preparation system and preparation method, the treatment system comprises: a sorting device, a pyrolysis device, a combustion reactor, and a drying device, wherein the high-temperature flue gas generated by the combustion reactor is transported to the pyrolysis device and the drying device via a pipeline. The preparation method comprises: screening the combustible waste in the waste to be treated; the combustible waste is divided into two parts, wherein one part of the combustible waste is used for pyrolysis treatment to generate pyrolysis gas, and then the pyrolysis gas is burned to generate high-temperature flue gas; the high-temperature flue gas is used to provide heat for the pyrolysis device and the drying device, and the other part of the combustible waste is dried to prepare solid recovered fuel. The solid recovered fuel preparation system and preparation method do not require an external drying heat source, and can realize energy recycling within the system while treating the waste.

Description

Technical Field

[0001] The present invention relates to the technical field of garbage disposal, and in particular to a solid recovered fuel preparation system and a preparation method. Background Art

[0002] Incineration power generation, as a harmless, reduced and resource-based treatment method, has gradually become the main method of waste disposal in my country. However, the cost of building a waste incineration power plant is high, and it also requires a certain scale of waste treatment, otherwise it is difficult to generate benefits.

[0003] In rural areas, it is difficult to implement waste incineration power plants due to the small amount of waste treatment and financial pressure. Therefore, many rural areas choose to landfill the waste. However, if the landfill is far away from the residential area, it will cause traffic inconvenience and increase transportation costs; if the landfill is close to the residential area, it will pollute the nearby living environment. In the long run, it will be difficult to fundamentally solve the problem of domestic waste in rural areas.

[0004] Solid recovered fuel (SRF) is a highly heterogeneous mixture prepared from the high calorific value part of non-hazardous waste. It is a new type of fuel after refuse-derived fuel (RDF) and can provide guarantees for equipment operation, combustion stability and low emissions of pollutants. In view of the small amount of garbage in rural areas, the method of preparing fixed recovered fuel can be adopted for treatment. Summary of the invention

[0005] The present invention is made to solve the above technical problems, and its purpose is to provide a solid recovered fuel preparation system that can effectively process garbage and make part of the combustibles therein into solid recovered fuel while consuming lower energy.

[0006] In order to achieve the above-mentioned objectives, the present invention provides a solid recovered fuel preparation system, comprising: a sorting device, used to sort out metals in the garbage to be processed; a pyrolysis device, receiving the garbage of a preset weight or volume and performing pyrolysis treatment to generate pyrolysis gas and pyrolysis slag; a combustion reactor, receiving the pyrolysis gas and / or pyrolysis slag and burning them to generate high-temperature flue gas; a drying device, receiving the high-temperature flue gas and the garbage of a preset weight or volume, and using the heat of the high-temperature flue gas to dry the received garbage into solid recovered fuel; a pipeline for conveying the high-temperature flue gas is also connected to the pyrolysis device to provide heat to the pyrolysis device.

[0007] Preferably, the high-temperature flue gas flows through the pyrolysis device and the drying device sequentially.

[0008] Preferably, it also includes: a flue gas purification device for purifying the high-temperature flue gas after heat exchange.

[0009] Preferably, a heat exchange device is provided on the periphery of the pyrolysis device, one end of the heat exchange device is connected to the high-temperature flue gas, and the other end of the heat exchange device is connected to the drying device.

[0010] Preferably, it also includes: a solid recovered fuel storage, which is connected to the drying device via a conveyor belt to receive and store the solid recovered fuel.

[0011] Preferably, the sorting device is also used to screen combustible waste in the waste to be processed.

[0012] In order to achieve the above object, the present invention provides a solid recovered fuel preparation method on the other hand, which is applied to the solid recovered fuel preparation system as described above, comprising the following steps:

[0013] The sorting device sorts out the metals in the garbage to be processed;

[0014] The pyrolysis device performs pyrolysis treatment on the garbage of a preset weight or volume to generate pyrolysis gas and pyrolysis slag;

[0015] The combustion reactor burns the pyrolysis gas and / or pyrolysis slag to generate high-temperature flue gas;

[0016] The drying device utilizes the high-temperature flue gas to dry the garbage of a preset weight or volume to generate solid recovered fuel.

[0017] Preferably, the heat source used by the pyrolysis device to perform pyrolysis treatment on the garbage of a preset weight or volume is the high-temperature flue gas.

[0018] Preferably, the high-temperature flue gas after heat exchange flowing out of the pyrolysis device and / or the drying device needs to be purified.

[0019] Preferably, the combustible waste is crushed before the pyrolysis treatment and the drying treatment.

[0020] According to the above description and practice, the solid recovered fuel preparation system and preparation method described in the present invention first uses a sorting device to sort out the metals in the garbage to be processed; a portion of the garbage is used for pyrolysis treatment to generate pyrolysis gas, and then the pyrolysis gas and / or pyrolysis slag are burned to generate high-temperature flue gas, and then the high-temperature flue gas is used to heat the pyrolysis device and the drying device, and the other part of the garbage is dried to generate solid recovered fuel. The preparation of solid recovered fuel by this system does not require the introduction of additional heat sources, which can reduce the cost of solid recovered fuel preparation, and can also process garbage. In addition, the present invention also purifies the high-temperature flue gas after the heat exchange flowing out of the drying device, which can avoid air pollution in the garbage treatment process. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic structural diagram of a solid recovered fuel preparation system according to an embodiment of the present invention.

[0022] Figure 2 The present invention is a schematic flow chart of a method for preparing solid recovered fuel according to an embodiment of the present invention. DETAILED DESCRIPTION

[0023] The exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that the disclosure will be more comprehensive and complete and fully convey the concepts of the exemplary embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0024] Unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] Figure 1 FIG. 1 is a schematic diagram of a solid recovered fuel preparation system according to an embodiment of the present invention. Figure 1 In this embodiment, the solid recovered fuel preparation system includes: a sorting device, a pyrolysis device, a combustion reactor and a drying device. The sorting device is used to sort out the metals in the garbage to facilitate subsequent pyrolysis and drying treatment. The pyrolysis device is used to perform pyrolysis treatment on part of the garbage to generate pyrolysis gas and pyrolysis slag. The pyrolysis gas and / or pyrolysis slag are transported to the combustion reactor for combustion to generate high-temperature flue gas. The drying device is used to dry the remaining garbage to generate solid recovered fuel. In this embodiment, the heat sources used by the drying device and the pyrolysis device are both the high-temperature flue gas generated by combustion in the combustion reactor.

[0026] The high-temperature flue gas exchanges heat when passing through the pyrolysis device or the drying device, and then the temperature is reduced. For this part of the high-temperature flue gas, further treatment is required before it can be discharged. Therefore, in the solid recovered fuel preparation system of this embodiment, a flue gas purification device is also provided to purify the high-temperature flue gas after the heat exchange flowing out of the pyrolysis device and the drying device.

[0027] In addition, in this embodiment, the solid recovered fuel preparation system further includes a garbage storage reservoir for storing garbage to be processed.

[0028] In addition, in order to improve the efficiency of pyrolysis and drying, the sorting device can also crush the garbage and further screen the combustible garbage in the garbage to be processed. For example, for domestic garbage, it can be divided into combustible garbage and other garbage. The combustible garbage can be used to prepare solid recycled fuel, and the other garbage is mainly non-combustible inorganic matter.

[0029] Specifically, the sorting device includes: a coarse crusher, a magnetic separator, a screening system, a winnowing machine, a fine crusher, a light garbage storage bin, a heavy garbage storage bin, and a belt conveyor for transporting materials between various devices. When in use, the garbage to be processed first enters the coarse crusher for crushing. After the coarse crushing, the garbage is transported to the magnetic separator by the belt conveyor to remove some of the magnetic metals carried in the garbage, such as iron, nickel, etc. After that, the garbage is transported to the screening system, and the garbage is screened into larger particles of the above-screen garbage and smaller particles of the below-screen garbage.

[0030] The above-screen garbage and the below-screen garbage are subjected to magnetic separation treatment using a magnetic separator to further separate the magnetic metals therein. Afterwards, the above-screen garbage and the below-screen garbage are subjected to wind separation using a pneumatic separator. It should be noted that since the particle size of the above-screen garbage is larger than that of the below-screen garbage, the power of the pneumatic separators used for the two is different. The power of the pneumatic separator used for the above-screen garbage is greater than that of the below-screen garbage.

[0031] After air separation, the sieved garbage is divided into light garbage and heavy garbage, and the sieved garbage is divided into light garbage and heavy garbage. The light garbage here refers to the above-mentioned combustible garbage, including organic matter such as wood and straw and combustible inorganic matter such as plastic and rubber; heavy garbage and magnetic metals are the above-mentioned non-combustible garbage, including metal, stone, tile, etc. The light garbage can be further crushed by a fine crusher to facilitate subsequent pyrolysis and drying treatment. Finally, the above-mentioned light garbage is transported to the light garbage storage bin, and the above-mentioned heavy garbage is transported to the heavy garbage storage bin. The particle size of the garbage crushed by the above-mentioned coarse crusher and fine crusher can be set according to actual needs, which will not be repeated here.

[0032] A method for mechanically sorting garbage into combustible garbage and non-combustible garbage is provided above. In other embodiments, other existing mechanical equipment may also be used to sort garbage into combustible garbage and non-combustible garbage, which will not be described in detail here.

[0033] The above sorting operation classifies the garbage for subsequent targeted treatment. For example, metals can be recycled, heavy garbage can be used as building materials, and light garbage can be used to prepare solid recycled fuel.

[0034] Specifically, in this embodiment, the pyrolysis device is a horizontal pyrolysis furnace, including a furnace body for performing pyrolysis reaction, and the furnace body has a garbage input port, a slag discharge port and an exhaust port. In addition, in order to improve the efficiency of pyrolysis, a heat exchange device is also provided on the outer side of the furnace body, one end of the heat exchange device is connected to a pipe for conveying high-temperature flue gas, and the other end is connected to a drying device, and the furnace body is heated by the heat of the high-temperature flue gas, thereby improving the pyrolysis efficiency. In one embodiment, the heat exchange device is a heating pipe wrapped around the outer side of the furnace body, one end of the heating pipe is connected to a pipe for conveying high-temperature flue gas, and the furnace body is heated by the high-temperature flue gas, thereby improving the pyrolysis efficiency; the other end of the heating pipe is connected to a drying device.

[0035] Lightweight waste is pyrolyzed in a horizontal pyrolysis furnace to generate pyrolysis gas and pyrolysis slag. The slag is discharged through the slag discharge port. The main components of the slag are tar and carbon black, which can be used as industrial raw materials. The pyrolysis gas and / or pyrolysis slag can be fed into a combustion reactor to burn and generate high-temperature flue gas.

[0036] Specifically, in this embodiment, the drying device can use high-temperature flue gas drying equipment to use the high-temperature flue gas to dry the light garbage therein, and the dried light garbage is solid recovered fuel. A solid recovered fuel reservoir is also provided at the rear end of the drying device, one end of which is connected to the drying device through a conveyor belt. The solid recovered fuel output by the drying device is stored in the solid recovered fuel reservoir, and the high-temperature flue gas after heat exchange in the drying device continues to flow forward into the flue gas purification device.

[0037] It should be noted that both the above-mentioned pyrolysis device and drying device process light garbage. Therefore, in practical applications, the light garbage obtained after sorting needs to be distributed. A certain weight or volume of light garbage can be pre-set for pyrolysis treatment, and a certain weight or volume of light garbage can be pre-set for drying treatment. Since pyrolysis treatment and drying treatment are continuous operations and require continuous feeding, when there is a lot of light garbage, the above-mentioned pyrolysis treatment and drying treatment can be carried out simultaneously without pre-distributing light garbage. Specifically, the high-temperature flue gas after the heat exchange between the pyrolysis device and the drying device must be purified by the flue gas purification device before being discharged.

[0038] In this embodiment, a method for preparing solid recovered fuel is also provided, using the above-mentioned solid recovered fuel preparation system, such as Figure 2 As shown, the solid recovered fuel preparation method comprises the following steps:

[0039] Step S1, the sorting device sorts out the metals in the garbage to be processed.

[0040] Taking domestic waste as an example, after mechanical sorting by the above-mentioned sorting device, domestic waste can be divided into combustible waste and other waste such as stones, magnetic metals, etc.

[0041] Step S2: The pyrolysis device performs pyrolysis treatment on the garbage of a preset weight or volume to generate pyrolysis gas and pyrolysis slag.

[0042] During pyrolysis, a preset weight or volume of combustible waste can be added according to the processing capacity of the pyrolysis device.

[0043] Step S3: The combustion reactor burns the pyrolysis gas and / or pyrolysis slag to generate high-temperature flue gas.

[0044] This step is carried out in a combustion reactor, and the generated high-temperature flue gas can be transported to subsequent processes through pipelines.

[0045] Step S4: The drying device uses the high-temperature flue gas to dry the garbage of a preset weight or volume to generate solid recovered fuel.

[0046] Specifically, the high-temperature flue gas can be first transported to a pyrolysis device through a pipeline to provide heat to the pyrolysis device to improve the efficiency of pyrolysis, and then flow into a drying device to dry the combustible waste in the drying device using the heat of the high-temperature flue gas to convert it into solid recovered fuel.

[0047] Finally, the high-temperature flue gas after heat exchange flowing out of the drying device needs to be purified before it can be discharged.

[0048] It should be noted that in this embodiment, a sorting device is provided that can screen combustible garbage in the garbage to be processed, and the combustible garbage screened by the sorting device is subjected to pyrolysis and drying treatment to improve the processing efficiency. In other embodiments, a sorting device that only includes a magnetic separator can also be directly selected. This sorting device only sorts out metal objects in the garbage, and then pyrolysis and drying treatment are performed on the remaining garbage, and pyrolysis gas and solid recovery fuel can also be obtained.

[0049] In addition, in this embodiment, the high-temperature flue gas generated in the combustion reactor first enters the heating pipe of the pyrolysis device to exchange heat, then enters the drying device to exchange heat, and finally enters the flue gas purification device for purification. In other embodiments, the generated high-temperature flue gas can also be divided into two parts, one part enters the heating pipe of the pyrolysis device to exchange heat, then enters the flue gas purification device, and the other part directly enters the drying device to exchange heat, and then enters the flue gas purification device. Both structural forms can realize the recovery and utilization of high-temperature flue gas heat.

[0050] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-limiting from all points of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention, and any reference numerals in the claims should not be regarded as limiting the claims involved.

Claims

1. A solid recovered fuel preparation system, characterized in that: include: The sorting device comprises a screening system, a pneumatic separator and a magnetic separator, and is used to sort out metals, light waste and heavy waste in the waste to be processed, wherein the waste is transported to the screening system to be separated into oversize waste and undersize waste, the magnetic separator performs magnetic separation treatment on the oversize waste and the undersize waste respectively, and the pneumatic separator separates the oversize waste and the undersize waste into light waste and heavy waste; A pyrolysis device receives the light waste of a preset weight or volume and performs pyrolysis treatment to generate pyrolysis gas and pyrolysis slag; A combustion reactor receives the pyrolysis gas and / or pyrolysis slag and burns them to generate high-temperature flue gas; A drying device receives the high-temperature flue gas and the light garbage of a preset weight or volume, and utilizes the heat of the high-temperature flue gas to dry the received garbage into solid recovered fuel; A solid recovered fuel depot, connected to the drying device via a conveyor belt, for receiving and storing the solid recovered fuel; The pipeline for conveying the high-temperature flue gas is also connected to the pyrolysis device to provide heat to the pyrolysis device.

2. The solid recovered fuel preparation system according to claim 1, characterized in that: The high-temperature flue gas flows through the pyrolysis device and the drying device in sequence.

3. The solid recovered fuel preparation system according to claim 1, characterized in that: Also includes: The flue gas purification device is used to purify the high-temperature flue gas after heat exchange.

4. The solid recovered fuel preparation system according to claim 2, characterized in that: A heat exchange device is provided on the periphery of the pyrolysis device, one end of the heat exchange device is connected to the high-temperature flue gas, and the other end of the heat exchange device is connected to the drying device.

5. The solid recovered fuel preparation system according to claim 1, characterized in that: The sorting device is also used to screen combustible garbage in the garbage to be processed.

6. A method for preparing solid recovered fuel, applied to the solid recovered fuel preparation system according to any one of claims 1 to 5, characterized in that: The following steps are involved: The sorting device sorts out the metals in the garbage to be processed; The pyrolysis device performs pyrolysis treatment on the garbage of a preset weight or volume to generate pyrolysis gas and pyrolysis slag; The combustion reactor burns the pyrolysis gas and / or pyrolysis slag to generate high-temperature flue gas; The drying device utilizes the high-temperature flue gas to dry the garbage of a preset weight or volume to generate solid recovered fuel.

7. The method for preparing solid recovered fuel as claimed in claim 6, characterized in that: The heat source used by the pyrolysis device to perform pyrolysis treatment on the garbage of a preset weight or volume is the high-temperature flue gas.

8. The method for preparing solid recovered fuel as claimed in claim 7, characterized in that: The high-temperature flue gas after heat exchange flowing out of the pyrolysis device and / or the drying device needs to be purified.

9. The method for preparing solid recovered fuel according to any one of claims 6 to 8, characterized in that: Before the pyrolysis treatment and the drying treatment, the combustible waste is also crushed.

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