A waste incineration flue gas waste heat recovery coupling dehumidification system

Abstract

This invention relates to the field of waste incineration waste heat utilization technology, and discloses a waste incineration flue gas waste heat recovery coupled dehumidification system, comprising: an inclined corrosion-resistant heat exchanger, a two-stage absorption heat pump quality improvement system, a membrane dehumidification coupled anti-corrosion system, and a condensate recovery and resource utilization unit; the inclined corrosion-resistant heat exchanger is internally equipped with a fluoroplastic-titanium alloy composite heat exchange surface and an acoustic descaling module, and is arranged at an overall inclination; the two-stage absorption heat pump quality improvement system is connected to the hot water outlet of the inclined corrosion-resistant heat exchanger; the membrane dehumidification coupled anti-corrosion system is connected to the cold flue gas outlet to perform deep dehumidification treatment on the flue gas; the condensate recovery and resource utilization unit treats the collected condensate for reuse; this invention solves the problems in the prior art of difficulty in recovering low-temperature flue gas waste heat from waste incineration, easy occurrence of dew point corrosion and ash accumulation blockage, and the still high humidity of the flue gas after waste heat recovery, which still requires further reduction of flue gas humidity to reduce the corrosion risk of subsequent systems.

Description

Technical Field

[0001] This invention relates to the field of waste incineration waste heat utilization technology, and in particular to a waste incineration flue gas waste heat recovery coupled dehumidification system. Background Technology

[0002] Waste-to-energy incineration is a core technology for the reduction, harmlessness, and resource recovery of waste, and an important support for the construction of "zero-waste cities." Currently, the temperature of flue gas from waste incineration plants after purification is 130-150℃, with about 15% of the total heat lost with the flue gas; the moisture content of the flue gas is 20%-25%, with huge latent heat, but existing technologies only cool it down to slightly above 100℃, recovering only a portion of the sensible heat and not utilizing the latent heat.

[0003] Existing waste heat recovery devices are mostly arranged horizontally or vertically, which makes it easy for condensed acid liquid to accumulate, causing low-temperature acid corrosion, ash blockage, and reduced heat exchange efficiency; moreover, they are mostly designed for gas-fired boilers and biomass boilers, and cannot be adapted to the highly corrosive and dusty conditions of waste incineration.

[0004] For waste incineration plants that supply steam externally, low-temperature steam / hot water cannot be reused, and ambient-temperature demineralized water is difficult to heat to the deaerator's design temperature, requiring additional heat consumption; at the same time, the low-temperature flue gas has high humidity, which can easily cause corrosion and "white smoke" problems in subsequent systems. Summary of the Invention

[0005] The present invention aims to provide a waste incineration flue gas waste heat recovery coupled with dehumidification system, in order to solve the problems in the existing technology that make it difficult to recover the waste heat of low-temperature flue gas from waste incineration, are prone to dew point corrosion and ash accumulation blockage, and still have high humidity after waste heat recovery, so that further reduction of flue gas humidity is still needed to reduce the corrosion risk of subsequent systems.

[0006] To achieve the above objectives, the present invention provides the following system and method:

[0007] This invention provides a waste incineration flue gas waste heat recovery coupled with dehumidification system, the system comprising:

[0008] The system includes an inclined arrangement of corrosion-resistant heat exchangers, a two-stage absorption heat pump system for upgrading the heat, a membrane dehumidification coupled with corrosion protection, and a condensate recovery and resource utilization unit.

[0009] The inclined corrosion-resistant heat exchanger is equipped with a fluoroplastic-titanium alloy composite heat exchange surface and an acoustic descaling module, and the entire inclined corrosion-resistant heat exchanger is inclined. The two-stage absorption heat pump quality improvement system is connected to the hot water outlet of the inclined corrosion-resistant heat exchanger, using the low-temperature hot water output from the inclined corrosion-resistant heat exchanger as a heat source. The membrane dehumidification coupled with anti-corrosion system is connected to the cold flue gas outlet of the inclined corrosion-resistant heat exchanger, and uses a corrosion-resistant polymer dehumidification membrane to perform deep dehumidification treatment on the flue gas. The condensate recovery and resource utilization unit is connected to the condensate outlet of the inclined corrosion-resistant heat exchanger and the condensate discharge port of the membrane dehumidification coupled with anti-corrosion system, and the condensate collected from both locations is treated and reused.

[0010] Preferably, the inclined corrosion-resistant heat exchanger further includes a hot flue gas inlet, a cold flue gas outlet, a cold water inlet, a hot water outlet, a condensate outlet, a shell, and a flue. The acoustic descaling module is located on the hot flue gas inlet side of the inclined corrosion-resistant heat exchanger. After passing through the inclined corrosion-resistant heat exchanger, the flue gas is discharged from the cold flue gas outlet. The inclined corrosion-resistant heat exchanger achieves gravity-guided discharge of condensed acid liquid through its overall inclined arrangement, avoiding liquid accumulation on the fluoroplastic-titanium alloy composite heat exchange surface, reducing fly ash adhesion on the fluoroplastic-titanium alloy composite heat exchange surface, and creating a self-cleaning effect on the fluoroplastic-titanium alloy composite heat exchange surface, while also enhancing the gas-liquid separation effect.

[0011] Preferably, the inclined corrosion-resistant heat exchanger stably reduces the temperature of the waste incineration flue gas (130-150℃, water content 20%-25%) to below the water dew point (60-65℃), achieving deep recovery of the sensible heat and latent heat of vaporization of the waste incineration flue gas; the fluoroplastic-titanium alloy composite heat exchange surface is suitable for waste incineration flue gas with high water content, high acidity, and high dust content.

[0012] Preferably, the dual-stage absorption heat pump upgrading system is a dual-stage structure with a low-pressure stage circulation and a high-pressure stage circulation coupled together. It uses the medium- and low-temperature waste heat generated by waste incineration as the driving heat source for the high-pressure stage circulation. The low-temperature hot water output by the inclined corrosion-resistant heat exchanger has a temperature of 40~60℃. The dual-stage absorption heat pump upgrading system heats the low-temperature hot water in stages and outputs high-temperature hot water at 90~150℃, heating the 20℃ ambient temperature demineralized water to the design temperature of the deaerator in the waste incineration plant.

[0013] Preferably, the low-pressure stage of the two-stage absorption heat pump upgrading system absorbs the 40~60℃ low-temperature heat source output by the inclined corrosion-resistant heat exchanger and completes the initial temperature rise; the high-pressure stage uses the steam generated by the low-pressure stage as a supplementary heat source to further heat the medium, and the COP of the two-stage absorption heat pump upgrading system is 1.5~2.5.

[0014] Preferably, the corrosion-resistant polymer dehumidification membrane of the membrane dehumidification coupled with corrosion protection system is a polyimide membrane or a perfluorosulfonic acid membrane. The membrane dehumidification coupled with corrosion protection system achieves flue gas dehumidification through the permeation and diffusion effect of the corrosion-resistant polymer dehumidification membrane. Specifically, high-humidity flue gas flows on one side of the corrosion-resistant polymer dehumidification membrane. Driven by the concentration difference and partial pressure difference, water vapor diffuses through the membrane wall to the purge side of the corrosion-resistant polymer dehumidification membrane. Dry gas is introduced into the purge side to carry away the water vapor diffused to that side, thereby achieving continuous dehumidification of the flue gas. The dry gas is dehumidified dry air or nitrogen.

[0015] Preferably, the membrane dehumidification coupled with corrosion prevention system reduces the moisture content and dew point temperature of flue gas, reduces the generation of acidic condensate, inhibits the corrosion of subsequent equipment, and achieves dry flue gas emissions. At the same time, it precisely controls the humidity in the high-humidity areas of the waste incineration plant storage pit and wet flue gas treatment workshop to below 60% relative humidity. The dehumidification accuracy of the membrane dehumidification coupled with corrosion prevention system reduces the dew point temperature of flue gas to below 50°C, and the membrane dehumidification coupled with corrosion prevention system has a structure without moving parts.

[0016] Preferably, the membrane dehumidification coupled with corrosion protection system is equipped with a pre-filter when the dust content of the flue gas is greater than 40%, and adopts a multi-stage series layout in high humidity flue gas treatment scenarios.

[0017] Preferably, the condensate recovery and resource utilization unit has a built-in water treatment system. The water treatment system purifies the collected condensate and reuses the treated condensate as industrial water or demineralized water for the waste incineration plant, thereby realizing the recycling of water resources, reducing the consumption of fresh water and meeting the water replenishment needs of water-scarce areas.

[0018] Preferably, the system further includes a flue gas purification system, an induced draft fan, and a chimney. The flue gas inlet of the flue gas purification system is connected to the flue gas outlet of the membrane dehumidification coupled anti-corrosion system. The air inlet of the induced draft fan is connected to the flue gas outlet of the flue gas purification system. The chimney is connected to the air outlet of the induced draft fan. After being deeply dehumidified by the membrane dehumidification coupled anti-corrosion system, the flue gas is purified by the flue gas purification system, transported by the induced draft fan, and then discharged as dry flue gas through the chimney.

[0019] The beneficial effects of this invention are reflected in:

[0020] 1. High-efficiency waste heat recovery: Deep recovery of sensible heat and latent heat, significantly improving energy utilization and reducing carbon emissions and operating costs;

[0021] 2. Corrosion-resistant, clog-resistant, and durable: The inclined arrangement allows for rapid drainage and self-cleaning, significantly reducing acid corrosion and dust accumulation, thus extending equipment life;

[0022] 3. Adaptable to combustion conditions: The dual-stage heat pump directly supplies heat to the deaerator, solving the problem of heating demineralized water in externally supplied steam combustion plants;

[0023] 4. Deep dehumidification and corrosion prevention: Membrane dehumidification reduces flue gas humidity, inhibits subsequent corrosion, eliminates white smoke, and controls humidity in the plant area;

[0024] 5. Water-saving and environmentally friendly: Condensate is efficiently recycled and reused, reducing the consumption of fresh water and making it suitable for water-scarce areas;

[0025] 6. Easy to maintain: Sonic descaling + self-cleaning structure reduces cleaning frequency and maintenance workload. Attached Figure Description

[0026] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0027] Figure 1 This is a schematic diagram of a waste incineration flue gas waste heat recovery coupled with dehumidification system provided in an embodiment of the present invention. Detailed Implementation

[0028] To enable those skilled in the art to better understand the present invention, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this invention are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, apparatus, product, or end that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or ends.

[0030] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0031] Existing waste heat recovery devices are mostly arranged horizontally or vertically, which makes it easy for condensed acid liquid to accumulate, causing low-temperature acid corrosion, ash blockage, and reduced heat exchange efficiency; moreover, they are mostly designed for gas-fired boilers and biomass boilers, and cannot be adapted to the highly corrosive and dusty conditions of waste incineration.

[0032] For waste incineration plants that supply steam externally, low-temperature steam / hot water cannot be reused, and ambient-temperature demineralized water is difficult to heat to the deaerator's design temperature, requiring additional heat consumption; at the same time, the low-temperature flue gas has high humidity, which can easily cause corrosion and "white smoke" problems in subsequent systems.

[0033] The present invention aims to provide a waste incineration flue gas waste heat recovery coupled with dehumidification system, in order to solve the problems in the existing technology that make it difficult to recover the waste heat of low-temperature flue gas from waste incineration, are prone to dew point corrosion and ash accumulation blockage, and still have high humidity after waste heat recovery, so that further reduction of flue gas humidity is still needed to reduce the corrosion risk of subsequent systems.

[0034] like Figure 1 As shown in the figure, a specific embodiment of the present invention provides a waste incineration flue gas waste heat recovery coupled dehumidification system, the system comprising the following components:

[0035] The system includes an inclined arrangement of corrosion-resistant heat exchangers, a two-stage absorption heat pump system for upgrading the heat, a membrane dehumidification coupled with corrosion protection, and a condensate recovery and resource utilization unit.

[0036] The inclined corrosion-resistant heat exchanger features a fluoroplastic-titanium alloy composite heat exchange surface and an acoustic descaling module. The entire heat exchanger is arranged at an incline. It also includes a hot flue gas inlet, a cold flue gas outlet, a cold water inlet, a hot water outlet, a condensate outlet, a shell, and a flue. The acoustic descaling module is located at the hot flue gas inlet side. After passing through the heat exchanger, the flue gas exits through the cold flue gas outlet. The inclined arrangement of the heat exchanger allows for gravity-driven discharge of condensed acid, preventing condensation. The liquid is placed on the fluoroplastic-titanium alloy composite heat exchange surface, reducing fly ash adhesion and creating a self-cleaning effect for the condensate, while also enhancing gas-liquid separation. The inclined arrangement of the corrosion-resistant heat exchanger stably reduces the temperature of waste incineration flue gas (130-150℃, water content 20%-25%) to below the water dew point (60-65℃), achieving deep recovery of sensible heat and latent heat of vaporization from the waste incineration flue gas. The fluoroplastic-titanium alloy composite heat exchange surface is suitable for waste incineration flue gas with high water content, high acidity, and high dust content.

[0037] The two-stage absorption heat pump upgrading system is connected to the hot water outlet of an inclined corrosion-resistant heat exchanger, using the low-temperature hot water output from the inclined corrosion-resistant heat exchanger as the heat source. The two-stage structure consists of a low-pressure stage cycle and a high-pressure stage cycle, with the medium-low temperature waste heat generated from waste incineration serving as the driving heat source for the high-pressure stage cycle. The low-temperature hot water output from the inclined corrosion-resistant heat exchanger has a temperature of 40~60℃. The two-stage absorption heat pump upgrading system then progressively heats the low-temperature hot water to output high-temperature hot water at 90~150℃, heating the 20℃ ambient temperature demineralized water to the design temperature of the waste incineration plant's deaerator. The low-pressure stage cycle of the two-stage absorption heat pump upgrading system absorbs the 40~60℃ low-temperature heat source output from the inclined corrosion-resistant heat exchanger and completes the initial temperature increase. The high-pressure stage cycle uses the steam generated by the low-pressure stage cycle as a supplementary heat source to further heat the medium. The COP of the two-stage absorption heat pump upgrading system is 1.5~2.5.

[0038] The membrane dehumidification coupled with corrosion protection system is connected to the cold flue gas outlet of an inclined corrosion-resistant heat exchanger. A corrosion-resistant polymer dehumidification membrane is used for deep dehumidification of the flue gas. The corrosion-resistant polymer dehumidification membrane in this system is either a polyimide membrane or a perfluorosulfonic acid membrane. The system achieves flue gas dehumidification through the permeation and diffusion effect of the membrane. Specifically, high-humidity flue gas flows on one side of the membrane. Driven by concentration and partial pressure differences, water vapor diffuses through the membrane wall to the purge side of the membrane. Dry gas is introduced into the purge side to carry away the diffused water vapor, achieving continuous dehumidification of the flue gas. The gas is either dehumidified dry air or nitrogen. The membrane dehumidification coupled with corrosion protection system reduces the moisture content and dew point temperature of flue gas, reduces the generation of acidic condensate, inhibits the corrosion of subsequent equipment, and achieves dry flue gas emissions. At the same time, it precisely controls the humidity in high-humidity areas of waste incineration plant storage pits and wet flue gas treatment workshops to below 60% relative humidity. The dehumidification accuracy of the membrane dehumidification coupled with corrosion protection system reduces the flue gas dew point temperature to below -40℃, and the membrane dehumidification coupled with corrosion protection system has no moving parts. When the dust content of the flue gas is greater than 40%, the membrane dehumidification coupled with corrosion protection system is equipped with a pre-filter component, and a multi-stage series layout is adopted in high-humidity flue gas treatment scenarios.

[0039] The condensate recovery and resource utilization unit is connected to the condensate outlet of the inclined corrosion-resistant heat exchanger and the condensate discharge outlet of the membrane dehumidification coupled anti-corrosion system. The condensate collected from these two locations is treated and reused. The condensate recovery and resource utilization unit has a built-in water treatment system. The water treatment system purifies the collected condensate and reuses the treated condensate as industrial water or demineralized water for the waste incineration plant, realizing water resource recycling, reducing fresh water consumption, and meeting the water replenishment needs of water-scarce areas. It also includes a flue gas purification system, an induced draft fan, and a chimney. The flue gas inlet of the flue gas purification system is connected to the flue gas outlet of the membrane dehumidification coupled anti-corrosion system, the air inlet of the induced draft fan is connected to the flue gas outlet of the flue gas purification system, and the chimney is connected to the air outlet of the induced draft fan. The flue gas, after being deeply dehumidified by the membrane dehumidification coupled anti-corrosion system, is purified by the flue gas purification system, transported by the induced draft fan, and then discharged as dry flue gas through the chimney.

[0040] Example 1

[0041] This invention provides a waste incineration flue gas waste heat recovery coupled with dehumidification system, suitable for waste incineration plant flue gas waste heat recovery and humidity control. The following is a description of the system in conjunction with the appendix. Figure 1 The specific working process and implementation details of this system are explained in detail:

[0042] Flue gas waste heat recovery stage: The flue gas generated by the waste incinerator, after heat exchange in the waste heat boiler and economizer, forms flue gas with a temperature of 130-150℃ and a moisture content of 20%-25%. This flue gas enters the equipment through the hot flue gas inlet of the inclined corrosion-resistant heat exchanger. At room temperature, cold water enters through the cold water inlet and exchanges heat with the flue gas on the fluoroplastic-titanium alloy composite heat exchange surface. The inclined corrosion-resistant heat exchanger is designed with the entire system tilted. The condensed acid produced during the cooling process flows downwards along the heat exchange surface under gravity and is discharged from the condensate outlet to the condensate recovery and resource utilization unit. This prevents condensate from accumulating on the heat exchange surface, and the condensate also provides a self-cleaning effect on the heat exchange surface. This, combined with the acoustic descaling module on the hot flue gas inlet side, further enhances the cooling process. Effectively prevents fly ash accumulation and blockage on the heat exchange surface; after heat exchange, the flue gas temperature is stably reduced to below the water dew point of 60-65℃, achieving deep recovery of sensible heat and latent heat of vaporization. The cooled, high-humidity flue gas is discharged from the cold flue gas outlet to the membrane dehumidification coupled with anti-corrosion system. The cooled water after heat exchange is heated to a low-temperature hot water of 40-60℃ and discharged from the hot water outlet to the two-stage absorption heat pump upgrading system. A fluoroplastic-titanium alloy composite heat exchange surface is adopted, with an overall inclined arrangement, combined with an acoustic descaling module; gravity is used to achieve rapid drainage and discharge of condensed acid liquid, avoiding liquid accumulation and corrosion; the inclined heat exchange surface reduces fly ash adhesion, and the condensate forms a self-cleaning effect, enhancing gas-liquid separation, improving heat exchange efficiency, and stably reducing the flue gas temperature below the water dew point to recover latent heat.

[0043] Waste heat upgrading and demineralized water heating stage: The two-stage absorption heat pump upgrading system uses the medium- and low-temperature waste heat generated by waste incineration as the driving heat source for the high-pressure stage cycle, which raises the temperature of the input 40~60℃ low-temperature hot water in stages. The low-pressure stage cycle first absorbs the low-temperature heat source to complete the initial temperature rise, and the high-pressure stage cycle then uses the steam generated by the low-pressure stage cycle as a supplementary heat source for further temperature rise. Under the condition of COP 1.5~2.5, the final output is high-temperature hot water of 90~150℃. This high-temperature hot water is directly used for demineralization at room temperature of 20℃. Water is heated to bring the demineralized water to the design temperature of the deaerator in the waste incineration plant. The heated demineralized water is then transported to the deaerator for production use, achieving efficient cascade utilization of low-grade waste heat without the need for additional heat energy to heat the demineralized water. Low-temperature hot water at 40-60℃ recovered by an inclined heat exchanger is used as a heat source and heated by a two-stage absorption heat pump to output high-temperature hot water at 90-150℃, directly heating the demineralized water to the temperature required by the deaerator. This solves the problem of heating demineralized water in externally supplied steam incineration plants and achieves efficient cascade utilization of low-grade waste heat.

[0044] Deep dehumidification stage of flue gas: High-humidity flue gas (60-65℃) discharged from the inclined corrosion-resistant heat exchanger enters the membrane dehumidification coupled with anti-corrosion system. This system uses a polyimide membrane as the corrosion-resistant polymer dehumidification membrane. The high-humidity flue gas flows on one side of the dehumidification membrane. Driven by the concentration difference and partial pressure difference, water vapor diffuses through the membrane wall to the purge side of the dehumidification membrane. Dehumidified dry air is introduced into the purge side as a drying gas to carry away the water vapor diffused to that side, thus achieving continuous dehumidification of the flue gas. In this embodiment, the dehumidification accuracy of the membrane dehumidification coupled with anti-corrosion system reduces the flue gas dew point temperature to a level that is lower than the standard dehumidification temperature. Below 50℃, the condensate generated during dehumidification is also discharged to the condensate recovery and resource utilization unit. If the dust content of the flue gas is too high, a pre-filter can be added to the flue gas inlet of the membrane dehumidification coupled with anti-corrosion system. If ultra-high humidity flue gas is to be treated, multiple membrane dehumidification modules can be arranged in series in multiple stages. Corrosion-resistant polymer dehumidification membranes are used to deeply dehumidify the high humidity flue gas after waste heat recovery, reducing the water content and dew point temperature of the flue gas. This reduces the generation of acidic condensate, inhibits the corrosion of subsequent equipment, achieves dry flue gas emission, and allows for precise humidity control in high humidity areas of the plant.

[0045] Condensate Resource Utilization Stage: The condensate recovery and resource utilization unit centrally collects the condensate from the inclined corrosion-resistant heat exchanger and the membrane dehumidification coupled anti-corrosion system. The condensate is then purified through its built-in water treatment system. The treated condensate is directly reused as industrial water in the waste incineration plant or transported to the demineralized water supply system as makeup water for demineralized water, thus realizing the recycling of water resources and reducing the consumption of fresh water. The condensate generated by the heat exchanger and membrane dehumidification is centrally collected, treated, and reused as industrial water and demineralized water makeup water, achieving water conservation and resource recycling.

[0046] Flue gas emission stage: After being deeply dehumidified by the membrane dehumidification coupled with anti-corrosion system, the dry flue gas enters the flue gas purification system for further purification. After being transported by the induced draft fan, it is discharged from the chimney as dry flue gas, which completely eliminates the "white smoke" phenomenon in flue gas emissions. Moreover, due to the significant reduction in flue gas humidity, the corrosion risk of subsequent equipment such as flue gas purification system, induced draft fan, and chimney is effectively reduced.

[0047] Meanwhile, the membrane dehumidification coupled with corrosion prevention system can be connected to high-humidity areas such as waste incineration plant storage pits and wet flue gas treatment workshops through pipelines to precisely dehumidify the air in the area, controlling the relative humidity of the area to below 60%, thus avoiding problems such as equipment condensation, electrical short circuits and mold growth caused by high humidity environments.

[0048] The beneficial effects of this invention are reflected in:

[0049] 1. High-efficiency waste heat recovery: Deep recovery of sensible heat and latent heat, significantly improving energy utilization and reducing carbon emissions and operating costs;

[0050] 2. Corrosion-resistant, clog-resistant, and durable: The inclined arrangement allows for rapid drainage and self-cleaning, significantly reducing acid corrosion and dust accumulation, thus extending equipment life;

[0051] 3. Adaptable to combustion conditions: The dual-stage heat pump directly supplies heat to the deaerator, solving the problem of heating demineralized water in externally supplied steam combustion plants;

[0052] 4. Deep dehumidification and corrosion prevention: Membrane dehumidification reduces flue gas humidity, inhibits subsequent corrosion, eliminates white smoke, and controls humidity in the plant area;

[0053] 5. Water-saving and environmentally friendly: Condensate is efficiently recycled and reused, reducing the consumption of fresh water and making it suitable for water-scarce areas;

[0054] 6. Easy to maintain: Sonic descaling + self-cleaning structure reduces cleaning frequency and maintenance workload.

[0055] The above descriptions are merely embodiments of the present invention. Commonly known technical solutions or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A waste incineration flue gas waste heat recovery coupled with dehumidification system, characterized in that, The system includes: an inclined corrosion-resistant heat exchanger, a two-stage absorption heat pump system for quality improvement, a membrane dehumidification coupled with corrosion prevention system, and a condensate recovery and resource utilization unit. The inclined corrosion-resistant heat exchanger is equipped with a fluoroplastic-titanium alloy composite heat exchange surface and an acoustic descaling module, and the entire inclined corrosion-resistant heat exchanger is inclined. The two-stage absorption heat pump quality improvement system is connected to the hot water outlet of the inclined corrosion-resistant heat exchanger, using the low-temperature hot water output from the inclined corrosion-resistant heat exchanger as a heat source. The membrane dehumidification coupled with anti-corrosion system is connected to the cold flue gas outlet of the inclined corrosion-resistant heat exchanger, and uses a corrosion-resistant polymer dehumidification membrane to perform deep dehumidification treatment on the flue gas. The condensate recovery and resource utilization unit is connected to the condensate outlet of the inclined corrosion-resistant heat exchanger and the condensate discharge port of the membrane dehumidification coupled with anti-corrosion system, and the condensate collected from both locations is treated and reused.

2. The waste incineration flue gas waste heat recovery coupled dehumidification system according to claim 1, characterized in that: The inclined corrosion-resistant heat exchanger also includes a hot flue gas inlet, a cold flue gas outlet, a cold water inlet, a hot water outlet, a condensate outlet, a shell, and a flue. The acoustic descaling module is installed on the hot flue gas inlet side of the inclined corrosion-resistant heat exchanger. After passing through the inclined corrosion-resistant heat exchanger, the flue gas is discharged from the cold flue gas outlet. The inclined corrosion-resistant heat exchanger achieves gravity-guided discharge of condensed acid liquid through its overall inclined arrangement, avoiding liquid flow on the fluoroplastic-titanium alloy composite heat exchange surface, reducing fly ash adhesion on the fluoroplastic-titanium alloy composite heat exchange surface, and creating a self-cleaning effect on the fluoroplastic-titanium alloy composite heat exchange surface, while also enhancing the gas-liquid separation effect.

3. The waste incineration flue gas waste heat recovery coupled dehumidification system according to claim 2, characterized in that: The inclined corrosion-resistant heat exchanger stably reduces the temperature of the waste incineration flue gas (130-150℃, 20%-25% water content) to below the water dew point (60-65℃), achieving deep recovery of the sensible heat and latent heat of vaporization of the waste incineration flue gas; the fluoroplastic-titanium alloy composite heat exchange surface is suitable for waste incineration flue gas with high water content, high acidity, and high dust content.

4. The waste incineration flue gas waste heat recovery coupled dehumidification system according to claim 1, characterized in that: The dual-stage absorption heat pump upgrading system is a dual-stage structure with a low-pressure stage circulation and a high-pressure stage circulation coupled together. It uses the medium- and low-temperature waste heat generated by waste incineration as the driving heat source for the high-pressure stage circulation. The low-temperature hot water output by the inclined corrosion-resistant heat exchanger has a temperature of 40~60℃. The dual-stage absorption heat pump upgrading system heats the low-temperature hot water in stages and outputs high-temperature hot water at 90~150℃, heating the 20℃ ambient temperature demineralized water to the design temperature of the deaerator in the waste incineration plant.

5. The waste incineration flue gas waste heat recovery coupled dehumidification system according to claim 4, characterized in that: The low-pressure stage of the two-stage absorption heat pump upgrading system absorbs the 40~60℃ low-temperature heat source output by the inclined corrosion-resistant heat exchanger and completes the initial temperature rise; the high-pressure stage uses the steam generated by the low-pressure stage as a supplementary heat source to further heat the medium. The COP of the two-stage absorption heat pump upgrading system is 1.5~2.

5.

6. The waste incineration flue gas waste heat recovery coupled dehumidification system according to claim 1, characterized in that: The corrosion-resistant polymer dehumidification membrane of the membrane-based dehumidification coupled with corrosion protection system is a polyimide membrane or a perfluorosulfonic acid membrane. The system achieves flue gas dehumidification through the penetration and diffusion effects of the corrosion-resistant polymer dehumidification membrane. Specifically: High-humidity flue gas flows on one side of the corrosion-resistant polymer dehumidification membrane. Driven by the concentration difference and partial pressure difference, water vapor diffuses through the membrane wall to the purging side of the corrosion-resistant polymer dehumidification membrane. Dry gas is introduced into the purging side to carry away the water vapor that has diffused to that side, thereby achieving continuous dehumidification of the flue gas. The drying gas is dehumidified dry air or nitrogen.

7. The waste incineration flue gas waste heat recovery coupled dehumidification system according to claim 6, characterized in that: The membrane dehumidification coupled with anti-corrosion system reduces the moisture content and dew point temperature of flue gas, reduces the generation of acidic condensate, inhibits the corrosion of subsequent equipment and achieves dry flue gas emission, while accurately controlling the humidity of high-humidity areas in the waste incineration plant storage pit and wet flue gas treatment workshop to below 60% relative humidity. The membrane dehumidification coupled with corrosion protection system achieves a dehumidification accuracy that reduces the flue gas dew point temperature to below 50°C, and the membrane dehumidification coupled with corrosion protection system has a structure without moving parts.

8. The waste incineration flue gas waste heat recovery coupled dehumidification system according to claim 1, characterized in that: The membrane dehumidification coupled with corrosion protection system is equipped with a pre-filter when the dust content of the flue gas is greater than 40%, and adopts a multi-stage series layout in high humidity flue gas treatment scenarios.

9. The waste incineration flue gas waste heat recovery coupled dehumidification system according to claim 1, characterized in that: The condensate recovery and resource utilization unit has a built-in water treatment system. The water treatment system purifies the collected condensate and reuses the treated condensate as industrial water or demineralized water for waste incineration plants, thereby realizing water resource recycling, reducing fresh water consumption and meeting the water replenishment needs of water-scarce areas.

10. The waste incineration flue gas waste heat recovery coupled dehumidification system according to claim 1, characterized in that: It also includes a flue gas purification system, an induced draft fan, and a chimney. The flue gas inlet of the flue gas purification system is connected to the flue gas outlet of the membrane dehumidification coupled anti-corrosion system. The air inlet of the induced draft fan is connected to the flue gas outlet of the flue gas purification system. The chimney is connected to the air outlet of the induced draft fan. After being deeply dehumidified by the membrane dehumidification coupled anti-corrosion system, the flue gas is purified by the flue gas purification system, transported by the induced draft fan, and then discharged as dry flue gas through the chimney.

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