Waste incineration system

Abstract

The waste incineration system comprises a waste feeding hopper, a combustion chamber and a slag discharging opening, a fire grate and a combustion partition plate are arranged in the combustion chamber, the combustion partition plate divides the combustion chamber into a first combustion chamber and a second combustion chamber, the first combustion chamber is communicated with a first smoke channel, and the second combustion chamber is communicated with a second smoke channel. The tail end of the first flue gas channel communicates with the tail end of the second flue gas channel through a mixing channel, at least one or more evaporators and a first water cooling pipeline are arranged in the first flue gas channel, and the evaporators and the first water cooling pipeline are used for generating saturated steam; at least one superheater is arranged in the second flue gas channel, and the superheaters utilize waste heat of low-chlorine flue gas generated by garbage combustion in the second combustion chamber to heat saturated steam to form high-temperature and high-pressure steam for power generation or other utilization. The flue gas waste heat utilization device can effectively reduce the influence of chlorine-containing compounds in flue gas on the superheater, realizes high-efficiency utilization of flue gas waste heat, and improves the power generation capacity per ton of garbage.

Description

Technical Field

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

[0002] Waste is a pollutant generated by human production activities. Large amounts of waste pose a significant threat to the environment, primarily by encroaching on land, polluting the atmosphere, soil, and water bodies, and the damage is difficult to reverse. Current urban waste disposal technologies are at a low level, and waste treatment requires substantial funding. Waste incineration technology addresses these issues. The high-temperature flue gas produced during incineration can serve as a primary energy source, generating high-pressure saturated steam for power generation. However, due to the complex composition of waste, combustion produces flue gas with a certain concentration of chlorine components. This chlorine continuously corrodes the superheater, the core equipment for generating high-temperature, high-pressure steam, affecting the stable operation of the equipment and system. It also limits the steam temperature generated by the superheater, preventing further increases in waste-to-energy efficiency.

[0003] According to the analysis of chlorine production during the waste incineration process, in traditional waste incineration systems, a large amount of chlorine-containing compounds are generated in the 200-500 degree Celsius range during the waste drying and initial combustion stages. This type of flue gas mixes with the low-chlorine flue gas at the end of the combustion process, continuously corroding and accumulating ash on the high-temperature superheater during the energy utilization of the flue gas. This ultimately affects the lifespan and heat transfer efficiency of the superheater, increases the risk of system operation, and may even lead to shutdown for maintenance.

[0004] Currently, some practitioners have addressed this issue by optimizing the surface material of the superheater to relatively reduce corrosion efficiency. However, this improvement method affects the heat transfer efficiency of flue gas and the modification cost is too high, impacting overall cost. How to effectively reduce the impact of chlorine-containing compounds in flue gas on the superheater in the waste incineration system, improve the thermal efficiency of the waste incineration system, increase the power generation per ton of waste, and reduce system maintenance costs are technical problems that urgently need to be solved by those skilled in the art. Utility Model Content

[0005] To address the technical problems existing in the prior art, this utility model provides a waste incineration system that can effectively reduce the impact of chlorine compounds in flue gas on the superheater in the waste incineration system, achieve high-efficiency utilization of flue gas waste heat, and increase the power generation per ton of waste.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] A waste incineration system includes a waste feed hopper, a combustion chamber, and a slag discharge port. The combustion chamber is equipped with a grate and a combustion baffle, which divides the combustion chamber into a first combustion chamber and a second combustion chamber. The first combustion chamber is connected to a first flue gas passage, and the second combustion chamber is connected to a second flue gas passage. The ends of the first and second flue gas passages are connected through a mixing passage. The first flue gas passage contains at least one evaporator and a first water-cooled pipe, which are used to generate saturated steam. The second flue gas passage contains at least one superheater, which uses the waste heat from the low-chlorine flue gas generated by the waste combustion in the second combustion chamber to heat the saturated steam into high-temperature, high-pressure steam for power generation or other uses.

[0008] As a further improvement of this utility model: the superheater includes a high-temperature superheater, a medium-temperature superheater and a low-temperature superheater.

[0009] As a further improvement of this utility model: the mixing channel is equipped with an economizer and a flue gas induced draft fan. The flue gas induced draft fan is used to introduce the flue gas generated by the first combustion chamber and the second combustion chamber into the first flue gas channel and the second flue gas channel, respectively. The economizer absorbs the waste heat of the mixed flue gas and is used to preheat the boiler feedwater before it enters the evaporator.

[0010] As a further improvement of this utility model: a second water-cooling pipe is provided inside the combustion baffle.

[0011] As a further improvement of this utility model, the grate is arranged in a stepped manner.

[0012] Compared with the prior art, the advantages of this utility model are:

[0013] 1. This utility model discloses a waste incineration system designed with a combustion baffle, dividing the traditional waste incineration chamber into two chambers: a first combustion chamber that produces flue gas with a high concentration of chlorinated compounds, and a second combustion chamber that produces flue gas with a lower concentration of chlorinated compounds. The first combustion chamber is connected to a first flue gas passage, and the second combustion chamber is connected to a second flue gas passage. An evaporator and a first water-cooled pipe are installed in the first flue gas passage. The evaporator and the first water-cooled pipe can fully absorb the residual heat from the high-chlorinated flue gas generated by waste combustion in the first combustion chamber to produce saturated steam. Because the working fluid temperature on the evaporation heating surface of the evaporator is relatively low, its pipe wall temperature does not reach the temperature range where chlorinated compounds cause high-speed corrosion, thus the overall corrosion degree is relatively mild. In the second flue gas passage, because the flue gas flowing through is high-temperature flue gas with a low concentration of chlorinated compounds, the corrosion rate of the high-temperature superheater is greatly reduced. Meanwhile, the superheater can more effectively utilize the waste heat of the high-temperature flue gas with lower chlorine content to generate high-temperature and high-pressure steam with higher parameters than traditional waste incineration superheaters, thereby achieving efficient utilization of flue gas waste heat and effectively increasing the power generation per ton of waste.

[0014] 2. In this waste incineration system, the ends of the first and second flue gas channels are connected via a mixing channel. The flue gas treated by the first and second channels is then remixed in the mixing channel. An economizer is installed in the mixing channel, which absorbs the waste heat from the mixed flue gas to preheat the boiler feedwater before it enters the evaporator. The saturated steam generated by the evaporator is then reheated by the superheater, transforming it into high-temperature, high-pressure steam. This achieves secondary utilization of the waste heat from the mixed flue gas, significantly improving the system's thermal efficiency. Compared to conventional waste incineration systems, this system innovatively differentiates and utilizes flue gas generated at different combustion stages. On one hand, it reduces the corrosive effect of high-concentration chlorine-containing flue gas on the superheater; on the other hand, it fully utilizes the heat from low-concentration chlorine-containing flue gas, achieving highly efficient utilization of waste heat and effectively increasing the power generation per ton of waste. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the waste incineration system of this utility model.

[0016] Legend:

[0017] 1. First combustion chamber; 2. Second combustion chamber; 3. Combustion baffle; 4. Mixing channel; 5. Waste feed hopper; 6. Grate; 101. First flue gas passage; 102. First water-cooled pipe; 103. Evaporator; 201. Second flue gas passage; 202. High-temperature superheater; 203. Medium-temperature superheater; 204. Low-temperature superheater; 301. Second water-cooled pipe; 401. Economizer; 402. Flue gas induced draft fan; 7. Ash discharge port. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings and specific preferred embodiments, but this does not limit the scope of protection of the present invention.

[0019] In the description of this utility model, it should be understood that the terms "side", "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0020] 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 technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "multiple" means two or more, unless otherwise explicitly specified.

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] like Figure 1 As shown, this embodiment provides a waste incineration system, including a waste feed hopper 5, a combustion chamber, and a slag discharge port 7. The combustion chamber is equipped with a grate 6 and a combustion baffle 3, which divides the combustion chamber into a first combustion chamber 1 and a second combustion chamber 2. The first combustion chamber 1 is connected to a first flue gas passage 101, and the second combustion chamber 2 is connected to a second flue gas passage 201. The ends of the first flue gas passage 101 and the second flue gas passage 201 are connected through a mixing passage 4. The first flue gas passage 101 contains at least one evaporator 103 and a first water-cooled pipe 102, which are used to generate saturated steam. The second flue gas passage 201 contains at least one superheater, which uses the waste heat from the low-chlorine flue gas generated by the waste combustion in the second combustion chamber 2 to heat the saturated steam to form high-temperature and high-pressure steam for power generation or other uses.

[0023] The waste incineration system in this embodiment is designed with a combustion baffle 3, dividing the traditional waste incineration chamber into two chambers: a first combustion chamber 1 that produces flue gas with a high concentration of chlorinated compounds, and a second combustion chamber 2 that produces flue gas with a lower concentration of chlorinated compounds. The first combustion chamber 1 is connected to the first flue gas passage 101, and the second combustion chamber 2 is connected to the second flue gas passage 201. An evaporator 103 and a first water-cooled pipe 102 are installed in the first flue gas passage 101. The evaporator 103 and the first water-cooled pipe 102 can fully absorb the residual heat from the high-chlorinated flue gas generated by the waste combustion in the first combustion chamber 1 to produce saturated steam. Because the working fluid temperature of the evaporation heating surface of the evaporator 103 is relatively low, its pipe wall temperature does not reach the temperature range where chlorinated compounds cause high-speed corrosion, thus the overall corrosion degree is relatively mild. In the second flue gas passage 201, because the flue gas flowing through is high-temperature flue gas with a low concentration of chlorinated compounds, the corrosion rate of the high-temperature superheater is greatly reduced. Meanwhile, the superheater can more effectively utilize the waste heat of the high-temperature flue gas with lower chlorine content to generate high-temperature and high-pressure steam with higher parameters than traditional waste incineration superheaters, thereby achieving efficient utilization of flue gas waste heat and effectively increasing the power generation per ton of waste.

[0024] In this embodiment, the superheater includes a high-temperature superheater 202, a medium-temperature superheater 203, and a low-temperature superheater 204. By setting up a three-stage superheater, the steam parameters are gradually increased, avoiding metal fatigue cracking caused by excessive temperature difference in a single-stage superheater, and greatly extending the service life of the equipment.

[0025] In this embodiment, the ends of the first flue gas passage 101 and the second flue gas passage 201 are connected by a mixing passage 4. The flue gas processed by the first and second flue gas passages will be mixed again in the mixing passage 4. The mixing passage 4 is equipped with an economizer 401 and a flue gas induced draft fan 402. The flue gas induced draft fan 402 is used to introduce the flue gas generated by the first combustion chamber 1 and the second combustion chamber 2 into the first flue gas passage 101 and the second flue gas passage 201, respectively. The economizer 401 absorbs the waste heat of the mixed flue gas and is used to preheat the boiler feedwater before it enters the evaporator 103, thereby realizing the secondary utilization of the waste heat of the mixed flue gas.

[0026] The saturated steam generated by evaporator 103, after being reheated by a superheater in a low-chlorine flue gas environment, is transformed into high-temperature, high-pressure steam with higher parameters than traditional waste incineration, thereby improving the system's power generation rate per ton of waste. Compared to conventional waste incineration systems, the waste incineration system in this embodiment innovatively differentiates and utilizes the flue gas generated at different combustion stages. On the one hand, it reduces the corrosive impact of high-concentration chlorine-containing flue gas on the superheater; on the other hand, it fully utilizes the heat of low-concentration chlorine-containing flue gas, achieving efficient utilization of flue gas waste heat and effectively increasing the power generation per ton of waste.

[0027] In this embodiment, a second water-cooling pipe 301 is provided inside the combustion baffle 3. Since the combustion baffle 3 is in the high-temperature environment of the combustion chamber for a long time, the design of the second water-cooling pipe 301 can achieve active cooling of the combustion baffle 3, avoid deformation of the combustion baffle 3 due to prolonged high temperature, realize the function of protecting the combustion baffle 3, and extend the service life of the combustion baffle 3. At the same time, the cooling water can absorb the heat of the combustion baffle 3 when flowing through the second water-cooling pipe 301. The heated cooling water can be directly used as preheated water for boiler feedwater, reducing the latent heat of vaporization demand of the evaporator 103, effectively realizing heat energy recovery and utilization, and improving the overall thermal efficiency of the system.

[0028] In this embodiment, the grate 6 is arranged in a stepped manner. By setting the grate 6 in a stepped manner in the combustion chamber, the waste is naturally stratified between multiple steps. When the waste falls from the top of the grate 6 layer by layer, the waste is broken up and turned over layer by layer, which is more conducive to the uniform heating of the waste.

[0029] Working principle: When the waste enters the combustion chamber from the waste feed hopper 5, under the action of the grate 6, the waste undergoes drying, combustion, and burnout to produce flue gas, and is finally discharged from the slag discharge port 7. Under the action of the combustion baffle 3, the garbage is dried and initially combusted in the first combustion chamber 1, producing flue gas at 200-500°C. The flue gas contains a high concentration of chlorine-containing compounds and enters the first flue gas passage 101 under the action of the flue gas induced draft fan 402. In the first flue gas passage 101, the evaporator 103 and the first water-cooling passage 104 fully absorb the residual heat from the high-chlorine flue gas produced by the garbage combustion in the first combustion chamber 1, producing saturated steam. In the second combustion chamber 2, the garbage combustion continues until it is completely burned, producing a lower concentration of chlorine-containing flue gas. Under the action of the flue gas induced draft fan 402, it enters the second flue gas passage 201. The saturated steam from the evaporator 103 is heated step by step through the low-temperature superheater 204, the medium-temperature superheater 203, and the high-temperature superheater 202. After being heated in the high-temperature superheater 202, it forms high-pressure high-temperature steam at about 450-500°C, which is then fed into the generator set for power generation and other uses. The flue gas, after being processed through the first and second flue gas passages, will be mixed again in the mixing passage 4. The economizer 401 can absorb the waste heat of the mixed flue gas to preheat the boiler feedwater before it enters the evaporator 103. The saturated steam generated by the evaporator 103 is reheated by the heat exchanger and converted into high-temperature and high-pressure steam, thereby realizing the secondary utilization of the waste heat of the mixed flue gas. All the heat of the flue gas is fully utilized.

[0030] Compared to traditional incinerators, this waste incineration system utilizes the varying chlorine concentrations in the flue gas generated at different combustion stages to partition the combustion chamber via combustion baffles 3. The generated flue gas is then utilized for heat generation through corresponding flue gas channels. The low-chlorine flue gas, operating in the superheater, allows for a higher steam temperature (400°C to 450-500°C) compared to traditional waste-to-energy technologies, thus increasing the power generation rate per ton of waste. This invention not only solves the problem of rapid superheater corrosion due to high chlorine content in a single flue gas channel, preventing the increase of steam temperature for power generation, but also achieves full utilization of flue gas heat, significantly improving the system's thermal efficiency.

[0031] The above are merely preferred embodiments of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions falling within the scope of this utility model's concept are within its protection scope. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of this utility model should be considered within its protection scope.

Claims

1. A waste incineration system, characterized by, The garbage feeding hopper (5), the combustion chamber, and the slag discharge port (7) are included, the combustion chamber is internally provided with the grate (6) and the combustion baffle (3), the combustion baffle (3) divides the combustion chamber into the first combustion chamber (1) and the second combustion chamber (2), the first combustion chamber (1) is communicated with the first flue gas passage (101), the second combustion chamber (2) is communicated with the second flue gas passage (201), the end of the first flue gas passage (101) and the end of the second flue gas passage (201) are communicated through the mixing passage (4), at least one or more than one evaporator (103) and the first water cooling pipeline (102) are arranged in the first flue gas passage (101), and the evaporator (103) and the first water cooling pipeline (102) are used to generate saturated steam; at least one superheater is arranged in the second flue gas passage (201), the superheater uses the waste heat of the low-chlorine flue gas generated by the garbage combustion in the second combustion chamber (2) to heat the saturated steam to form high-temperature and high-pressure steam for power generation.

2. The waste incineration system according to claim 1, characterized in that, The superheater includes the high-temperature superheater (202), the medium-temperature superheater (203), and the low-temperature superheater (204).

3. The waste incineration system according to claim 1, characterized in that, The mixing passage (4) is internally provided with the economizer (401) and the flue gas induced draft fan (402), the flue gas induced draft fan (402) is used to introduce the flue gas generated by the first combustion chamber (1) and the second combustion chamber (2) into the first flue gas passage (101) and the second flue gas passage (201) respectively, and the economizer (401) absorbs the waste heat of the mixed flue gas and is used to preheat the boiler feed water before entering the evaporator (103).

4. The waste incineration system according to any one of claims 1 to 3, characterized in that, The combustion baffle (3) is internally provided with the second water cooling pipeline (301).

5. The waste incineration system according to any one of claims 1 to 3, characterized in that, The grate (6) is arranged in a stepped manner.

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