Waste incineration system

Abstract

The utility model relates to the technical field of garbage treatment, in particular to a garbage incineration system which comprises a garbage incinerator, the garbage incinerator is connected with a high-temperature flue gas pipeline, a first heat exchanger and a second heat exchanger are arranged in the high-temperature flue gas pipeline, and the second heat exchanger is located on the side, close to the garbage incinerator, of the first heat exchanger. The first heat exchanger is provided with a first cold water inlet and a first steam outlet, the second heat exchanger is provided with a second steam inlet and a second steam outlet, the first steam outlet is connected with the second steam inlet, and the second steam outlet is connected with a first air preheater. The first air preheater is provided with a first preheated steam inlet, a first preheated air inlet and a first preheated air outlet, the first preheated steam inlet is connected with the second steam outlet, and the first preheated air outlet is connected with the garbage incinerator. Heat in high-temperature flue gas can be effectively utilized, combustion of garbage in the garbage incinerator is promoted through the heat of the flue gas, and meanwhile steam can be obtained to be used by other external equipment.

Description

Technical Field

[0001] This utility model relates to the field of waste treatment technology, and more specifically, to a waste incineration system. Background Technology

[0002] Waste incinerators are used to burn waste. The high-temperature flue gas generated during incineration is directly discharged, meaning the heat in the flue gas cannot be utilized, resulting in heat waste. Existing technologies also include devices that preheat air directly with flue gas before supplying it to the waste incinerator, but their utilization rate of the heat in the flue gas is low. Utility Model Content

[0003] To overcome the problem of low heat utilization rate of flue gas generated by waste incineration in the prior art, this utility model provides a waste incineration system to improve the heat utilization rate of flue gas generated by waste incinerators.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is: a waste incineration system, comprising: a waste incinerator, the waste incinerator being connected to a high-temperature flue gas duct, the high-temperature flue gas duct being provided with a first heat exchanger and a second heat exchanger, the second heat exchanger being located on the side of the first heat exchanger closer to the waste incinerator, the first heat exchanger having a first cold water inlet and a first steam outlet, the second heat exchanger having a second steam inlet and a second steam outlet, the first steam outlet being connected to the second steam inlet, the second steam outlet being connected to a first air preheater, the first air preheater having a first preheated steam inlet, a first preheated air inlet and a first preheated air outlet, the first preheated steam inlet being connected to the second steam outlet, and the first preheated air outlet being connected to the waste incinerator.

[0005] In this invention, a first heat exchanger and a second heat exchanger sequentially exchange heat with the high-temperature flue gas in a high-temperature flue gas duct. Water is heated in the first heat exchanger to generate wet steam, which is then introduced into the second heat exchanger. The second heat exchanger heats the wet steam to obtain superheated steam at an even higher temperature. This high-temperature superheated steam then heats air through a first air preheater, and the heated air is supplied to the waste incinerator. Because the second heat exchanger is located on the side of the first heat exchanger closer to the waste incinerator, the flue gas temperature it contacts is higher, thus effectively heating the wet steam. This solution effectively utilizes the heat in the high-temperature flue gas to generate hot air, promoting waste combustion in the incinerator, while simultaneously generating steam for use by other external equipment.

[0006] Furthermore, the waste incineration system also includes a second air preheater, which has a second preheated air inlet, a second preheated air outlet, and a second preheated steam inlet. The second preheated air outlet is connected to the first preheated air inlet, and the second preheated steam inlet is connected to the second steam outlet.

[0007] In this solution, the air can be preheated twice through the second air preheater and the first air preheater, and the resulting hot air temperature can reach 200 degrees Celsius. High-temperature superheated steam can also be obtained for users.

[0008] Furthermore, a pressure reducing device is also connected between the second preheated steam inlet and the second steam outlet.

[0009] In this scheme, the steam pressure obtained from the second air preheater can be reduced by the pressure reducing device, so as to meet the requirements of cold air volume heating.

[0010] Furthermore, a boiler drum is installed on the pipe connecting the first steam outlet and the second steam inlet.

[0011] In this scheme, the steam and water generated by the first heat exchanger are separated by the boiler drum, and the dry saturated steam is supplied to the second heat exchanger.

[0012] Furthermore, the second air preheater has a second preheated air inlet connected to a first fan, the first fan having a first air outlet and a first air inlet, the first air outlet being connected to the second preheated air inlet, and the second air inlet being in communication with the outside air.

[0013] In this scheme, the first fan can deliver outside air into the second air preheater.

[0014] Furthermore, a second fan is connected to the end of the high-temperature flue gas duct. The second fan has a second air inlet and a second air outlet. The second air inlet is connected to the end of the high-temperature flue gas duct, and the second air outlet is connected to a biomass gasification furnace.

[0015] In this scheme, a second fan can deliver hot flue gas at around 180 degrees Celsius into the biomass gasification furnace.

[0016] Furthermore, the biomass gasifier has a gasifier air inlet, a gasifier steam inlet, and an auxiliary flue gas inlet. The second air outlet is connected to the auxiliary flue gas inlet, the gasifier air inlet is connected to the first preheated air outlet, and the gasifier steam inlet is connected to the second preheated steam outlet.

[0017] In this scheme, some of the flue gas, steam and preheated air generated by the waste incinerator can promote the high-temperature gasification of biomass waste in the biomass gasification furnace.

[0018] Furthermore, the biomass gasifier has a biomass gas outlet, which is connected to a gas burner arranged on the side of the waste incinerator.

[0019] In this scheme, the biomass gasifier produces biomass gas that can assist the waste incinerator and promote the complete combustion of waste.

[0020] Furthermore, the biomass gasification furnace has a biomass waste inlet and a dry sludge inlet.

[0021] In this scheme, biomass waste and dry sludge are fed into a biomass gasifier for coupled gasification through a biomass waste inlet and a sludge inlet.

[0022] Furthermore, the high-temperature flue gas duct is connected to a chimney.

[0023] In this scheme, the cooled flue gas in the flue gas duct can be discharged through the chimney.

[0024] Furthermore, the waste incinerator is equipped with a feeding port.

[0025] In this scheme, the waste is fed into the waste incinerator through a feeding port for incineration.

[0026] Compared with the prior art, the beneficial effects of this utility model are:

[0027] I. The waste incineration system of this utility model exchanges heat with high-temperature flue gas in a high-temperature flue gas duct through a first heat exchanger and a second heat exchanger in sequence. In the first heat exchanger, water is heated to generate wet steam, which is then separated from the water in the boiler drum before being introduced into the second heat exchanger. The second heat exchanger heats the dry steam to obtain superheated steam at a higher temperature. The high-temperature superheated steam then heats air through a first air preheater, and the heated air is supplied to the waste incinerator. This solution effectively utilizes the heat in the high-temperature flue gas, improves the combustion efficiency of the waste incinerator, and provides steam for use by other external equipment.

[0028] Second, by setting up a first air preheater and a second air preheater, the outside air can be preheated twice, improving the air preheating effect. At the same time, two kinds of steam at different temperatures can be obtained for use by other external equipment. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of the waste incineration system of this utility model.

[0030] In the attached diagram: 1. Waste incinerator; 11. Feed inlet; 2. High-temperature flue gas duct; 21. Chimney; 3. First heat exchanger; 31. First cold water inlet; 32. First steam outlet; 4. Second heat exchanger; 41. Second steam inlet; 42. Second steam outlet; 5. First air preheater; 51. First preheated steam inlet; 52. First preheated air inlet; 53. First preheated air outlet; 54. First preheated steam outlet; 6. Second air preheater; 61. Second preheated air inlet 62. Second preheated air outlet; 63. Second preheated steam inlet; 64. Second preheated steam outlet; 7. Pressure reducing device; 8. Boiler drum; 81. Hot water outlet; 9. First fan; 91. First air outlet; 92. First air inlet; 10. Second fan; 101. Second air inlet; 102. Second air outlet; 12. Biomass gasifier; 121. Gasifier air inlet; 122. Gasifier steam inlet; 123. Auxiliary flue gas inlet; 124. Biomass gas outlet. Detailed Implementation

[0031] The accompanying drawings are for illustrative purposes only and should not be construed as limiting this patent. To better illustrate this embodiment, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings. The positional relationships described in the drawings are for illustrative purposes only and should not be construed as limiting this patent.

[0032] In the accompanying drawings of this utility model, the same or similar reference numerals correspond to the same or similar components. In the description of this utility model, it should be understood that if terms such as "upper," "lower," "left," "right," "long," and "short" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting this patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0033] The technical solution of this utility model will be further described in detail below through specific embodiments and in conjunction with the accompanying drawings:

[0034] Example 1

[0035] refer to Figure 1This embodiment discloses a waste incineration system, including a waste incinerator 1. The waste incinerator 1 is connected to a high-temperature flue gas duct 2. The high-temperature flue gas duct 2 is provided with a first heat exchanger 3 and a second heat exchanger 4. The second heat exchanger 4 is located on the side of the first heat exchanger 3 close to the waste incinerator 1. The first heat exchanger 3 has a first cold water inlet 31 and a first steam outlet 32. The second heat exchanger 4 has a second steam inlet 41 and a second steam outlet 42. The first steam outlet 32 ​​is connected to the second steam inlet 41. The second steam outlet 42 is connected to a first air preheater 5. The first air preheater 5 has a first preheated steam inlet 51, a first preheated air inlet 52 and a first preheated air outlet 53. The first preheated steam inlet 51 is connected to the second steam outlet 42, and the first preheated air outlet 53 is connected to the waste incinerator 1.

[0036] In this embodiment, the high-temperature flue gas in the high-temperature flue gas duct 2 is exchanged with the first heat exchanger 3 and the second heat exchanger 4 in sequence. Water is heated in the first heat exchanger 3 to generate wet steam, which is then separated from the water in the boiler drum before being introduced into the second heat exchanger 4. The second heat exchanger 4 heats the dry saturated steam to obtain superheated steam at a higher temperature. The high-temperature superheated steam is then used by the first air preheater 5 to heat the air, which is then supplied to the waste incinerator 1. Because the second heat exchanger 4 is located on the side of the first heat exchanger 3 closest to the waste incinerator 1, the flue gas temperature in contact with the second heat exchanger 4 is higher, thus effectively heating the dry saturated steam. This solution can effectively utilize the heat in the high-temperature flue gas and improve the combustion efficiency of the waste incinerator 1. The first air preheater 5 is provided with a first preheated steam outlet 54 for supplying steam to other external equipment (e.g., ejectors).

[0037] refer to Figure 1 High-temperature flue gas flows through the high-temperature flue gas duct 2, with the end closer to the waste incinerator 1 being the upstream and the end farther from the waste incinerator being the downstream. The second heat exchanger 4 is located on the side of the first heat exchanger 3 closest to the waste incinerator 1, that is, the second heat exchanger 4 is located upstream of the high-temperature flue gas duct 2, and the first heat exchanger 3 is located downstream of the high-temperature flue gas duct 2. Therefore, the flue gas in contact with the second heat exchanger 4 has a higher temperature.

[0038] In this embodiment, the waste incinerator 1 generates high-temperature flue gas during combustion. This high-temperature flue gas is used to heat the first heat exchanger 3 and the second heat exchanger 4, thereby utilizing the heat in the flue gas. The high-temperature flue gas generated by the waste incinerator 1 is discharged from the high-temperature flue gas duct 2, where the second heat exchanger 4 is located closer to the waste incinerator 1. The high-temperature flue gas can first contact the second heat exchanger 4 and then the first heat exchanger 3, resulting in a higher temperature of the flue gas in contact with the second heat exchanger 4. The temperature of the flue gas in contact with the first heat exchanger 3 is slightly lower, but still much higher than the boiling point of water. Cold water is introduced into the first heat exchanger 3, and the heated cold water generates wet steam. After the water is separated by the boiler drum, the steam is introduced into the second heat exchanger 4. The flue gas in contact with the second heat exchanger 4 is at a higher temperature, thus further heating the dry saturated steam into superheated steam at an even higher temperature.

[0039] The waste incineration system in this embodiment fully utilizes the heat in the high-temperature flue gas through secondary heating to obtain high-temperature superheated steam. Part of this superheated steam is used by the user, while the other part is further heated by an air preheater to obtain higher-temperature air, which is then introduced into the waste incinerator 1. This fully utilizes the heat generated by the combustion of waste to promote continued combustion. Compared to existing technologies that directly preheat air with flue gas, this solution first uses high-temperature flue gas to reheat water to obtain high-temperature steam, and then uses this high-temperature steam to preheat the air. This fully utilizes the heat in the flue gas, reduces the exhaust temperature, and also provides steam for use by other external equipment.

[0040] In this embodiment, the high-temperature flue gas duct 2 is connected to a chimney 21. The treated flue gas has a lower temperature, and the remaining flue gas can be discharged through the chimney 21.

[0041] In this embodiment, the waste incinerator 1 is provided with a feeding port 11. The feeding port 11 facilitates the feeding of waste into the waste incinerator 1, enabling timely replenishment of waste and ensuring the continuous operation of the incineration process.

[0042] Example 2

[0043] refer to Figure 1 This embodiment is similar to Embodiment 1, except that in this embodiment, reference is used. Figure 1 The waste incineration system also includes a second air preheater 6, which has a second preheated air inlet 61, a second preheated air outlet 62, and a second preheated steam inlet 63. The second preheated air outlet 62 is connected to the first preheated air inlet 52, and the second preheated steam inlet 63 is connected to the second steam outlet 42.

[0044] In this embodiment, the second air preheater 6 can preheat the external air initially, and then the preheated air is passed into the first air preheater 5 for secondary preheating, making the air preheating more thorough and the temperature higher. Simultaneously, after passing through the first or second preheater, two different temperatures of steam can be obtained, which can be used for other external equipment with different steam temperature requirements. The steam can be discharged through the second preheated steam outlet 64 of the second preheater for use by other equipment. Specifically, the air preheater in this embodiment is a steam-air preheater, the principle of which is to heat the air within it using steam; the specific structure can be referred to in the prior art.

[0045] For example, in some embodiments, the air preheater includes an air channel and a steam channel. The air channel has a preheated air inlet and a preheated air outlet, and the steam channel has a preheated steam inlet and a preheated steam outlet. The steam channels are distributed within the air channels and are not interconnected. Therefore, when high-temperature steam flows through the steam channels, it can heat the air in the air channels. The air and steam do not come into direct contact, preventing moisture from being introduced into the air. Compared to heating air with flue gas, using steam heating also prevents the air preheater from coming into contact with flue gas, avoiding corrosion of the air preheater by flue gas.

[0046] In this embodiment, a pressure reducing device 7 is also connected between the second preheated steam inlet 63 and the second steam outlet 42. The pressure reducing device 7 can reduce the steam pressure, thereby obtaining lower-pressure steam for use by other external equipment.

[0047] refer to Figure 1 A boiler drum 8 is installed on the pipe connecting the first steam outlet 32 ​​and the second steam inlet 41. The boiler drum 8, also called a steam drum, receives water and steam from the first heat exchanger and performs steam-water separation. The separated water can enter an external water tank for storage through the hot water outlet 81 and can be recycled back to the first heat exchanger 3 for reheating. Saturated steam is obtained through separation in the boiler drum 8 and supplied to the second heat exchanger 4 for heating, thereby obtaining high-temperature, high-pressure superheated steam. The boiler drum 8 itself can store a certain amount of water, which acts as a buffer, ensuring stable system operation.

[0048] In this embodiment, the second preheated air inlet 61 of the second air preheater 6 is connected to a first fan 9. The first fan 9 has a first air outlet 91 and a first air inlet 92. The first air outlet 91 is connected to the second preheated air inlet 61, and the second air inlet 101 is in communication with the outside air. The first fan 9 sends outside air into the second air preheater 6 to preheat the air.

[0049] Example 3

[0050] refer to Figure 1 This embodiment is similar to Embodiment 1, except that in this embodiment, a second fan 10 is connected to the end of the high-temperature flue gas duct 2. The second fan 10 has a second air inlet 101 and a second air outlet 102. The second air inlet 101 is connected to the end of the high-temperature flue gas duct 2, and the second air outlet 102 is connected to the biomass gasifier 12. The hot flue gas from the high-temperature flue gas duct 2 is sent out by the second fan 10 for use in the biomass gasifier 12. The hot flue gas can act as a gasifying agent to react with the biomass waste in the biomass gasifier 12, while reducing nitrogen oxide emissions. In some embodiments, the steam used by the second air preheater 6 can be introduced into the biomass gasifier 12 and used together with the flue gas as a gasifying agent.

[0051] In this embodiment, the biomass gasifier 12 has a gasifier air inlet 121, a gasifier steam inlet 122, and an auxiliary flue gas inlet 123. A second air outlet 102 is connected to the auxiliary flue gas inlet 123, the gasifier air inlet 121 is connected to a first preheated air outlet 53, and the gasifier steam inlet 122 is connected to a second preheated steam outlet 64. Specifically, the gasifier air inlet 121 supplies preheated air to the gasifier, the gasifier steam inlet 122 supplies steam to the biomass gasifier 12, and the auxiliary flue gas inlet 123 supplies flue gas generated by the waste incinerator 1 to the biomass gasifier 12. By forming a mixed gasification dose from flue gas, air, and steam, the biomass waste in the biomass gasifier 12 is coupled and gasified, which can improve the gasification efficiency of the biomass waste and increase the hydrogen content in the fuel gas, thereby increasing the calorific value of the fuel gas.

[0052] Biomass fuels in solid waste have a high volatile content, allowing them to be gasified into fuel gas which is then burned in a waste incinerator, releasing heat and significantly increasing combustion temperature and efficiency. The solution described in this embodiment effectively achieves the gasification and combustion of biomass fuels in solid waste.

[0053] In this embodiment, the biomass gasifier 12 has a biomass gas outlet 124, which is connected to the waste incinerator 1. Specifically, the biomass gasifier 12 generates biomass gas, which is supplied through the biomass gas outlet 124 to a burner (not shown) arranged on the side wall of the waste incinerator 1, thereby promoting the combustion of waste in the waste incinerator 1. The waste incinerator 1 and the biomass gasifier 12 can mutually promote the reaction, improving the efficiency of waste and biomass waste treatment.

[0054] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating this utility model, and are not intended to limit the implementation of this utility model. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A waste incineration system, characterized in that: The system includes a waste incinerator (1), which is connected to a high-temperature flue gas duct (2). The high-temperature flue gas duct (2) is provided with a first heat exchanger (3) and a second heat exchanger (4). The second heat exchanger (4) is located on the side of the first heat exchanger (3) close to the waste incinerator (1). The first heat exchanger (3) has a first cold water inlet (31) and a first steam outlet (32). The second heat exchanger (4) has a second steam inlet (41) and a second steam outlet (42). The first steam outlet (32) is connected to the second steam inlet (41). The second steam outlet (42) is connected to a first air preheater (5). The first air preheater (5) has a first preheated steam inlet (51), a first preheated air inlet (52), and a first preheated air outlet (53). The first preheated steam inlet (51) is connected to the second steam outlet (42), and the first preheated air outlet (53) is connected to the waste incinerator (1).

2. The waste incineration system according to claim 1, characterized in that: The waste incineration system further includes a second air preheater (6), which has a second preheated air inlet (61), a second preheated air outlet (62), and a second preheated steam inlet (63). The second preheated air outlet (62) is connected to the first preheated air inlet (52), and the second preheated steam inlet (63) is connected to the second steam outlet (42).

3. The waste incineration system according to claim 2, characterized in that: A pressure reducing device (7) is connected between the second preheated steam inlet (63) and the second steam outlet (42).

4. The waste incineration system according to claim 1, characterized in that: A boiler drum (8) is installed on the pipe connecting the first steam outlet (32) and the second steam inlet (41).

5. The waste incineration system according to claim 2, characterized in that: The second air preheater (6) has a second preheated air inlet (61) connected to a first fan (9). The first fan (9) has a first air outlet (91) and a first air inlet (92). The first air outlet (91) is connected to the second preheated air inlet (61), and the first air inlet (92) is connected to the outside air.

6. The waste incineration system according to claim 1, characterized in that: The high-temperature flue gas duct (2) is connected to a second fan (10) at its end. The second fan (10) has a second air inlet (101) and a second air outlet (102). The second air inlet (101) is connected to the end of the high-temperature flue gas duct (2), and the second air outlet (102) is connected to a biomass gasification furnace (12).

7. The waste incineration system according to claim 6, characterized in that: The biomass gasifier (12) has a gasifier air inlet (121), a gasifier steam inlet (122) and an auxiliary flue gas inlet (123). The second air outlet (102) is connected to the auxiliary flue gas inlet (123). The gasifier air inlet (121) is connected to the first preheated air outlet (53). The gasifier steam inlet (122) is connected to the second preheated steam outlet (64).

8. The waste incineration system according to claim 7, characterized in that: The biomass gasifier (12) has a biomass gas outlet (124), and a burner is provided on the side wall of the waste incinerator. The biomass gas outlet (124) is connected to the burner.

9. The waste incineration system according to claim 6, characterized in that: The biomass gasifier (12) has a biomass waste inlet and a dry sludge inlet.

10. The waste incineration system according to claim 1, characterized in that: The high-temperature flue gas duct (2) is connected to a chimney (21), and the waste incinerator (1) is equipped with a feeding port (11).

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