Waste heat gradient utilization device based on efficient heat exchange of garbage power generation

Abstract

The waste heat gradient utilization device comprises a boiler, a first draught fan, a second draught fan, a desulfurizing tower, a dust remover and a waste heat recovery unit, the first draught fan is connected to the upper portion of one side of the boiler, the second draught fan is fixedly connected to the lower portion of one side of the boiler, the waste heat recovery unit is connected to one side of the dust remover, and the desulfurizing tower is fixedly connected to the lower portion of the other side of the boiler. A chimney is fixed on one side of the waste heat recovery unit, the waste heat recovery unit is divided into three stages of spraying, the first stage is a flue gas purification spraying section and is mainly used for removing HCL in flue gas, a water diversion demisting device is arranged at the upper end of the first stage, and first-stage spraying water is independently provided with a circulating pump for circulation and is not mixed with second-stage spraying water and third-stage spraying water. The flue gas purification device has the advantages that water film type direct contact heat exchange is adopted, the heat exchange efficiency is high, heat exchange is stable, after flue gas is subjected to first-stage spraying purification, water-soluble HCL in the flue gas is basically removed, clean flue gas enters the second-stage spraying layer and the third-stage spraying layer through the gas rising pipe, second-stage spraying water and third-stage spraying water make contact with the clean flue gas, and the water quality is good.

Description

Technical Field

[0001] This utility model relates to the field of waste heat recovery technology, specifically to a waste heat cascade utilization device based on efficient heat exchange in waste-to-energy power generation. Background Technology

[0002] A waste-to-energy high-efficiency heat exchange and waste heat cascade utilization device is a device or system used to recover and utilize the waste heat generated during waste incineration. This device typically comprises multiple components to achieve multi-stage utilization of waste heat, thereby improving energy efficiency and reducing waste.

[0003] In the waste heat recovery process, the flue gas generated during waste-to-energy production contains a considerable amount of heat. If the recovery efficiency is low, most of the heat will be discharged into the environment with the waste gas and cannot be effectively utilized, resulting in serious energy waste. At the same time, the flue gas from waste treatment is corrosive and will damage the heat exchange and utilization device for power generation. Therefore, it is necessary to provide a heat exchange and waste heat utilization device that can be highly efficient and improve the service life of the device. Utility Model Content

[0004] The purpose of this invention is to provide a waste heat cascade utilization device based on efficient heat exchange in waste-to-energy power generation, thereby solving the problems mentioned in the background section. To solve these technical problems, this invention is achieved through the following technical solution:

[0005] This utility model is a waste heat cascade utilization device based on efficient heat exchange in waste-to-energy power generation, comprising:

[0006] The boiler, first fan, second fan, desulfurization tower, dust collector, and waste heat recovery unit are connected together. The first fan is connected to the upper side of the boiler, the second fan is fixedly connected to the lower side of the boiler, the desulfurization tower is fixedly connected to the side of the boiler's pipe, the dust collector is connected to the side of the desulfurization tower, and the waste heat recovery unit is connected to the side of the dust collector. Connecting pipes connect the various components.

[0007] Furthermore, a waste heat pump is installed between the dust collector and the waste heat recovery unit. A chimney is fixed on one side of the waste heat recovery unit. The waste heat recovery unit has three-stage spraying. The first stage is a flue gas purification spraying section, which mainly removes HCl from the flue gas. A water separation and demisting device is installed at the upper end of the first stage. The spraying water of the first stage is circulated by a separate circulating pump and is not mixed with the spraying water of the second and third stages.

[0008] Furthermore, a heat exchanger is connected to one side of the waste heat recovery unit, and a heat pump unit is connected to one end of the heat exchanger.

[0009] Furthermore, one end of the heat exchanger is connected to the return water of the heating network, and one end of the heat pump unit is connected to the supply water of the heating network.

[0010] Further, the other end of the heat pump unit is connected to a condensate water tank, and one end of the heat pump unit is connected to a steam heater.

[0011] Further, a steam distribution cylinder is connected to one side of the heat pump unit, and one end of the first fan and the second fan is connected to a refuse bunker.

[0012] Further, a flue damper is added to the chimney flue from the outlets of the first fan and the second fan. Before the damper, the flue gas is introduced into the waste heat recovery unit. After the heat is recovered, the flue gas returns to enter the chimney after the newly added damper. Meanwhile, dampers are added at the inlet and outlet of the waste heat recovery unit to cut out the waste heat recovery system in the non-heating season.

[0013] The utility model has the following beneficial effects:

[0014] In the utility model, a water film type direct contact heat exchange is adopted, with high heat exchange efficiency and stable heat exchange. After the flue gas is purified by primary spray, the water-soluble HCL in the flue gas is basically removed. The clean flue gas enters the secondary and tertiary spray layers through the riser pipe. The secondary and tertiary spray water contacts the clean flue gas, and the water quality is good. The flue gas is bounded by the dampers at the inlet and outlet of the waste heat recovery unit. Considering the chimney anti-corrosion, the existing chimney is re-anti-corroded to ensure the chimney anti-corrosion performance. The purified flue gas enters the heat exchange system, and the chloride ions in the heat exchange system are greatly reduced. The materials of the heat exchange system are all made of anti-corrosion materials. The materials in contact with the fluid such as the water pump and pipeline supporting the waste heat recovery unit are all selected with anti-corrosion performance not lower than that of stainless steel to ensure the safe and stable operation of the system. Alkali liquor is regularly added to the surplus hot water in the waste heat recovery system of the flue gas to make the waste heat system of the flue gas in an alkaline environment to reduce the system corrosion. Description of the Drawings

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0016] Figure 1 It is a flow chart of the present utility model;

[0017] Figure 2 For the present utility model Figure 1 The enlarged view at A in it.

[0018] In the drawings, the list of components represented by each reference numeral is as follows:

[0019] 1. Boiler; 101. First blower; 102. Second blower; 2. Desulfurization tower; 3. Dust collector; 301. Waste water pump; 4. Waste heat recovery unit; 5. Chimney; 6. Heat exchanger; 7. Heat pump unit; 8. Heat network return water; 9. Heat network supply water; 10. Condensate tank; 11. Steam heater; 12. Steam distribution cylinder; 13. Waste bin. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0021] To make the objectives, technical solutions, and advantages of this utility model clearer, the embodiments of this utility model will be described in further detail below with reference to the accompanying drawings.

[0022] Please see Figure 1-2 As shown, this utility model is a waste heat cascade utilization device based on efficient heat exchange in waste-to-energy power generation, comprising:

[0023] Boiler 1, first fan 101, second fan 102, desulfurization tower 2, dust collector 3 and waste heat recovery unit 4. The first fan 101 is connected to the upper side of one side of boiler 1, the second fan 102 is fixedly connected to the lower side of one side of boiler 1, the desulfurization tower 2 is fixedly connected to one side of the pipeline of boiler 1, the dust collector 3 is connected to one side of desulfurization tower 2, and the waste heat recovery unit 4 is connected to one side of dust collector 3. The connecting pipes are connected between the various components.

[0024] A waste heat pump 301 is installed between the dust collector 3 and the waste heat recovery unit 4. A chimney 5 is fixed on one side of the waste heat recovery unit 4. The waste heat recovery unit 4 is divided into three spray stages. The first stage is the flue gas purification spray stage, which mainly removes HCl from the flue gas. A water separation and demisting device is installed at the upper end of the first stage. The spray water of the first stage is circulated by a separate circulating pump and is not mixed with the spray water of the second and third stages.

[0025] A heat exchanger 6 is connected to one side of the waste heat recovery unit 4. A heat pump unit 7 is connected to one end of the heat exchanger 6. A heat network return water 8 is connected to one end of the heat exchanger 6. A heat network supply water 9 is connected to one end of the heat pump unit 7. A condensate tank 10 is connected to the other end of the heat pump unit 7. A steam heater 11 is connected to one end of the heat pump unit 7.

[0026] A steam distribution cylinder 12 is connected to one side of the heat pump unit 7. A garbage bin 13 is connected to one end of the first fan 101 and the second fan 102. A flue gate is added to the flue from the outlet of the first fan 101 and the second fan 102 to the chimney 5. The flue gas is introduced into the waste heat recovery unit 4 in front of the gate. After the heat is recovered, the flue gas returns to the newly added gate and enters the chimney 5. At the same time, gates are added to the inlet and outlet of the waste heat recovery unit 4. The waste heat recovery system is cut off during the non-heating season.

[0027] Working principle

[0028] Flue gas flow: The flue gas from the outlet of the induced draft fan is introduced into the flue gas waste heat recovery unit 4. After heat exchange between the flue gas and the waste water in the flue gas, the flue gas temperature drops to about 30°C and then returns to the original chimney 5.

[0029] Flue gas waste heat recovery system: The waste heat water temperature of the 575t / h flue gas waste heat recovery system is about 62.5℃. After being pumped by the waste heat water supply pump, it is supplied to the heat exchanger return water 8 of the heating network heating plate and heated from 50℃ to 60.6℃. The temperature of the waste water drops to about 52℃. Part of it is returned to the waste heat recovery unit 4 for spray heat exchange, and the other part is extracted by the absorption heat pump unit 7 to reduce the temperature to 25℃. Then it is returned to the flue gas waste heat recovery system for heat exchange, and the flue gas temperature is finally reduced to 30℃. The cycle continues.

[0030] The hot water flow process is as follows: all the hot water from the 518t / h, 50℃ hot water network enters the flue gas waste heat recovery heat exchange station. It is first heated to 60.6℃ by the 62.5℃ flue gas waste water. Then the hot water network water enters the absorption heat pump unit 7, which heats it from 60.6℃ to 85℃ and supplies it to the outside.

[0031] The heating system is equipped with a heat network heater as a supplement and backup device to the waste heat recovery system. The heat network heater has a heat exchange capacity of 21MW and is located at the end of the waste heat recovery system to ensure the safety and stability of heating in the event of a failure or maintenance of the waste heat recovery system.

[0032] Flue gas condensate process: Reduce flue gas temperature to 30℃, recover 12t / h of flue gas condensate, add a membrane water treatment unit, entrust a third party to treat the concentrated water produced by the water treatment unit, and the treated water can be used as heating network makeup water or other process water.

[0033] This step employs a water film direct contact heat exchanger, which boasts high heat exchange efficiency and stability. After primary spray purification, water-soluble HCl in the flue gas is largely removed. The clean flue gas then enters the secondary and tertiary spray layers via riser pipes. The secondary and tertiary spray water comes into contact with the clean flue gas, ensuring good water quality. The flue gas is demarcated by the inlet and outlet gates of the waste heat recovery unit. Considering the corrosion resistance of chimney 5, the existing chimney 5 is re-coated to ensure its corrosion resistance. The purified flue gas enters the heat exchange system, where chloride ions are significantly reduced. All materials used in the heat exchange system are corrosion-resistant. The water pumps, pipes, and other materials in contact with the fluid associated with the waste heat recovery unit 4 are made of materials with corrosion resistance no less than stainless steel, ensuring safe and stable system operation. Alkali solution is periodically added to the waste water in the flue gas waste heat recovery system to maintain an alkaline environment and reduce system corrosion.

[0034] The preferred embodiments of this utility model disclosed above are merely illustrative of the present utility model. These preferred embodiments do not exhaustively describe all details, nor do they limit the utility model to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, thereby enabling those skilled in the art to better understand and utilize it. This utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A waste heat cascade utilization device based on efficient heat exchange in waste-to-energy power generation, characterized in that, include: Boiler (1), first fan (101), second fan (102), desulfurization tower (2), dust collector (3) and waste heat recovery unit (4). The first fan (101) is connected to the upper side of the boiler (1), the second fan (102) is fixedly connected to the lower side of the boiler (1), the desulfurization tower (2) is fixedly connected to the pipe side of the boiler (1), the dust collector (3) is connected to the side of the desulfurization tower (2), and the waste heat recovery unit (4) is connected to the side of the dust collector (3). The connecting pipes are connected between the various components.

2. The waste heat cascade utilization device based on high-efficiency heat exchange in waste-to-energy power generation according to claim 1, characterized in that: A waste heat pump (301) is installed between the dust collector (3) and the waste heat recovery unit (4). A chimney (5) is fixed on one side of the waste heat recovery unit (4). The waste heat recovery unit (4) is divided into three spray stages. The first stage is the flue gas purification spray stage, which mainly removes HCl from the flue gas. A water separation and demisting device is set at the upper end of the first stage. The first stage spray water is circulated by a separate circulating pump and is not mixed with the second and third stage spray water.

3. The waste heat cascade utilization device based on high-efficiency heat exchange in waste-to-energy power generation according to claim 2, characterized in that: A heat exchanger (6) is connected to one side of the waste heat recovery unit (4), and a heat pump unit (7) is connected to one end of the heat exchanger (6).

4. The waste heat cascade utilization device based on high-efficiency heat exchange in waste-to-energy power generation according to claim 3, characterized in that: One end of the heat exchanger (6) is connected to the return water of the heating network (8), and one end of the heat pump unit (7) is connected to the supply water of the heating network (9).

5. The waste heat cascade utilization device based on high-efficiency heat exchange in waste-to-energy power generation according to claim 4, characterized in that: The other end of the heat pump unit (7) is connected to a condensate tank (10), and the other end of the heat pump unit (7) is connected to a steam heater (11).

6. The waste heat cascade utilization device based on high-efficiency heat exchange in waste-to-energy power generation according to claim 5, characterized in that: A steam distribution cylinder (12) is connected to one side of the heat pump unit (7), and a garbage bin (13) is connected to one end of the first fan (101) and the second fan (102).

7. The waste heat cascade utilization device based on high-efficiency heat exchange in waste-to-energy power generation according to claim 2, characterized in that: A flue gate is added to the flue from the outlet of the first fan (101) and the second fan (102) to the chimney (5). The flue gas is introduced into the waste heat recovery unit (4) in front of the gate. After the heat is recovered, the flue gas returns to the newly added gate and enters the chimney (5). At the same time, gates are added at the inlet and outlet of the waste heat recovery unit (4) to cut off the waste heat recovery system during the non-heating season.

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