Deep recovery device for waste heat of medium and low temperature flue gas

Abstract

The utility model discloses a deep recovery device for waste heat of medium and low temperature flue gas, which relates to the technical field of flue gas waste heat recovery, and comprises a first heat exchange component, a second heat exchange component, a third heat exchange component, a fourth heat exchange component and a fourth heat exchange component, the partition plate divides the interior of the first shell into a smoke cavity and a water cavity which are independent. A second heat exchange assembly; the shell at least comprises a second shell; the first heat exchange assembly and the second heat exchange assembly are used in cooperation, flue gas is subjected to two-stage heat exchange, high-temperature flue gas is subjected to first-stage heat exchange through the stainless steel heat exchange piece, heat is transmitted into the water cavity, heat energy recovery is achieved, low-temperature flue gas is subjected to second-stage heat exchange through the fluoroplastic thin pipe heat exchange piece, and heat energy recovery is achieved. And the low-temperature flue gas after one-time heat exchange can be conveniently reused, the heat exchange efficiency is further improved, and the flue gas waste heat utilization rate can be effectively increased through the arrangement.

Description

Technical Field

[0001] The utility model relates to the technical field of flue gas waste heat recovery, in particular to a medium- and low-temperature flue gas waste heat deep recovery device. Background Art

[0002] With the rapid development of industrialization, energy consumption and environmental pollution are becoming increasingly serious. In many industrial processes, flue gas emissions are an important source of pollution, which contains a large amount of waste heat and harmful substances. Traditional flue gas treatment methods, such as waste heat boilers or heat exchangers, can recover some of the waste heat of flue gas, but the exhaust temperature is still high, the waste heat utilization rate is limited, and the effect of reducing the emission of harmful substances in the flue gas is not ideal; at the same time, due to the high temperature of the flue gas, the moisture in the flue gas is still in a steam state and is discharged into the atmosphere along with the flue gas. In winter, a "white plume" phenomenon will appear near the chimney, creating conditions for the formation of haze.

[0003] To this end, we designed a medium and low temperature flue gas waste heat deep recovery device to solve the above problems. Utility Model Content

[0004] The purpose of the utility model is to provide a medium- and low-temperature flue gas waste heat deep recovery device to solve the problems raised in the above-mentioned background technology.

[0005] In order to solve the above technical problems, the utility model provides a medium and low temperature flue gas waste heat deep recovery device, comprising:

[0006] A first heat exchange assembly at least comprises a first shell, wherein a plurality of stainless steel heat exchange elements arranged at intervals and a transversely arranged partition are arranged in the first shell, wherein the partition divides the interior of the first shell into an independent smoke chamber and a water chamber;

[0007] The second heat exchange assembly comprises at least a second shell, wherein a fluoroplastic thin tube heat exchange element is arranged in the second shell;

[0008] The first heat exchange component and the second heat exchange component are connected through a pipeline.

[0009] Furthermore, the first heat exchange component also includes a steam drum arranged on one side of the first shell, one side of the steam drum is connected to the water cavity opened in the first shell through a mounting pipe, and the steam drum is respectively provided with an air outlet and a water outlet.

[0010] Furthermore, a desalted water connecting pipe is connected to one side of the first shell, one end of the desalted water connecting pipe extends into the water cavity, and one end of the air outlet is connected to the desalted water connecting pipe through a saturated water connecting pipe.

[0011] Furthermore, the second heat exchange component also includes a normal temperature tap water connecting pipe connected to one side of the second shell, one end of the normal temperature tap water connecting pipe extends into the second shell and is connected to the water inlet end of the fluoroplastic capillary heat exchanger, and the water outlet end of the fluoroplastic capillary heat exchanger extends to the outside of the second shell.

[0012] Furthermore, the second shell also includes a spray cleaning component, which includes a spray water delivery pipe connected to one side of a normal temperature tap water connecting pipe, one end of the spray water delivery pipe extends into the second shell and is connected to a spray pipe, and a plurality of nozzles are arranged at equal intervals on the spray pipe, and the nozzles are located above the fluoroplastic capillary heat exchanger.

[0013] Furthermore, the spray cleaning assembly also includes a dosing mechanism disposed on one side of the second shell, and a liquid outlet end of the dosing mechanism is connected to the spray delivery pipe through a cleaning solution delivery pipe.

[0014] Furthermore, it also includes a protection component, which includes an emergency exhaust duct connected to the pipeline, and the emergency exhaust duct is provided with a smoke damper valve, and the smoke damper valve is used to open when the smoke temperature is high.

[0015] Furthermore, a clean water recovery component is also provided in the second shell, and the clean water recovery component includes a water collection well connected to the second shell, and one side of the water collection well is connected to a recycling water pump for extracting liquid in the water collection well.

[0016] Compared with the prior art, the beneficial effects of the utility model are:

[0017] 1. Through the coordinated use of the first heat exchange component and the second heat exchange component, the flue gas is divided into two stages of heat exchange. The higher temperature flue gas uses stainless steel heat exchange components for the first stage of heat exchange, and the heat is transferred to the water cavity to realize the recovery of heat energy. The lower temperature flue gas uses fluoroplastic thin tube heat exchange components for the second stage of heat exchange, which is convenient for the reuse of the low-temperature flue gas after the heat exchange, and further improves the heat exchange efficiency. This setting can effectively improve the utilization rate of flue gas waste heat.

[0018] 2. Through the spray cleaning component, the outer surface of the fluoroplastic capillary heat exchanger can be regularly rinsed and cleaned to eliminate dust and scaling and improve heat exchange efficiency. At the same time, the dosing mechanism set in the spray cleaning component can add sodium carbonate or sodium bicarbonate to the recovered condensate water to neutralize the acidic substances such as SO2 and NOx dissolved and absorbed in the condensate water to reduce the corrosion of acidic substances to equipment and pipelines. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The utility model is a flow chart of a medium and low temperature flue gas waste heat deep recovery device.

[0020] In the figure: 1. Steam drum; 2. Stainless steel heat exchanger; 3. Flue gas damper valve; 4. Recycling water pump; 5. Second shell; 6. Spray pipe; 7. Dosing mechanism; 8. Fluoroplastic capillary heat exchanger; 9. Water collection well. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] See also Figure 1 The utility model provides a technical solution: including:

[0023] The first heat exchange assembly comprises at least a first shell, in which a plurality of stainless steel heat exchange elements 2 arranged at intervals and a transversely arranged partition are arranged, and the partition divides the interior of the first shell into independent smoke chambers and water chambers;

[0024] The second heat exchange assembly comprises at least a second shell 5, in which a fluoroplastic thin tube heat exchange member 8 is disposed, and one side of the second shell 5 is connected to a smoke exhaust pipe;

[0025] The first heat exchange component and the second heat exchange component are connected through a pipeline.

[0026] Preferably, the inner side of the pipeline is reinforced with resin glass flakes for corrosion protection or is manufactured with steel-plastic composite materials to extend the service life of the pipeline.

[0027] During specific implementation, the first heat exchange component and the second heat exchange component that are first set can be used in combination to make secondary use of the heat in the flue gas, effectively reducing heat loss. The stainless steel heat exchanger 2 in the first heat exchange component can exchange heat with the high-temperature flue gas and transfer the heat to the water cavity to realize heat energy recovery, while the fluoroplastic capillary heat exchanger 8 set in the second heat exchange component facilitates the reuse of the low-temperature flue gas after heat exchange once, further improving the heat exchange efficiency.

[0028] Furthermore, the first heat exchange assembly further includes a steam drum 1 disposed on one side of the first shell, one side of the steam drum 1 is connected to the water cavity opened in the first shell through a mounting pipe, and the steam drum 1 is provided with an air outlet and a water outlet respectively;

[0029] In specific implementation, when the stainless steel heat exchanger 2 absorbs the heat of the flue gas and transfers the heat to the water cavity, the water in the water cavity is heated to boiling to produce a steam-water mixture, which enters the steam drum 1 through the installation pipe. The steam-water mixture is separated in the steam drum 1, and qualified low-pressure saturated steam is output from the air outlet to the production unit for use, and the saturated water is discharged along the water outlet.

[0030] Furthermore, a desalted water connecting pipe is connected to one side of the first shell, one end of the desalted water connecting pipe extends into the water cavity, and one end of the air outlet is connected to the desalted water connecting pipe through a saturated water connecting pipe;

[0031] During specific implementation, the desalted water connecting pipe is convenient for introducing the desalted water from the outside into the water cavity, and the saturated water connecting pipe is convenient for sending the saturated water back to the desalted water pipeline inlet. After the saturated water is sent back to the desalted water pipeline inlet, it can be heated again and participate in the circulation, thereby improving the utilization efficiency of thermal energy.

[0032] Furthermore, the second heat exchange assembly also includes a normal temperature tap water connection pipe connected to one side of the second shell 5, one end of the normal temperature tap water connection pipe extends into the second shell 5 and is connected to the water inlet end of the fluoroplastic thin tube heat exchanger 8, and the water outlet end of the fluoroplastic thin tube heat exchanger 8 extends to the outside of the second shell 5;

[0033] During specific implementation, a normal temperature tap water connecting pipe is provided to facilitate the delivery of normal temperature tap water from the outside to the fluoroplastic capillary heat exchanger 8, so that the low temperature flue gas in the second shell 5 exchanges heat with the normal temperature tap water in the fluoroplastic capillary heat exchanger 8, heating it into medium temperature tap water for bathing, washing, etc., while the flue gas temperature is further reduced.

[0034] Furthermore, the second shell 5 also includes a spray cleaning assembly, which includes a spray water delivery pipe connected to one side of the normal temperature tap water connection pipe, one end of the spray water delivery pipe extends into the second shell 5 and is connected to a spray pipe 6, and a plurality of spray heads are arranged at equal intervals on the spray pipe 6, and the spray heads are located above the fluoroplastic capillary heat exchanger 8;

[0035] It should be noted that the material of the spray pipe 6 is 304 stainless steel or fluoroplastic;

[0036] During specific implementation, the flue gas often carries a portion of dust and dirt. As the use time increases, the dust and dirt are easily accumulated on the fluoroplastic capillary heat exchanger 8, affecting the heat exchange efficiency of the fluoroplastic capillary heat exchanger 8. For this reason, normal temperature tap water is introduced into the spray pipe 6 through a connecting pipe and the fluoroplastic capillary heat exchanger 8 is flushed through a nozzle to improve the heat exchange efficiency of the fluoroplastic capillary heat exchanger 8.

[0037] Furthermore, the spray cleaning assembly further includes a dosing mechanism 7 disposed on one side of the second shell 5, and a liquid outlet end of the dosing mechanism 7 is connected to the spray delivery pipe through a cleaning solution delivery pipe.

[0038] During specific implementation, a certain amount of solution can be mixed through the dosing mechanism 7. The solution in the dosing mechanism 7 can select a certain concentration of sodium carbonate or sodium bicarbonate solution (used to neutralize acidic substances such as SO2, NOx dissolved and absorbed in the condensate water), and then mixed with normal temperature tap water to spray the fluoroplastic capillary heat exchanger 8, thereby further improving the flushing effect of the fluoroplastic capillary heat exchanger 8.

[0039] Furthermore, a protection component is included, the protection component includes an emergency exhaust flue connected to the pipeline, and a smoke damper valve 3 is provided on the emergency exhaust flue, and the smoke damper valve 3 is used to open when the smoke temperature is high;

[0040] During specific implementation, considering that in the event of an accident of the primary heat exchange component, the flue gas temperature cannot be effectively reduced and remains high, the flue gas may damage the second shell 5. An emergency exhaust flue is provided in front of the entrance of the second shell 5, and a flue gas damper valve 3 is provided on the flue. The valve is in a closed state during normal operation and is opened only in the event of an accident of the primary heat exchange component to protect the second shell 5.

[0041] Furthermore, a clean water recovery component is also provided in the second shell 5 , and the clean water recovery component includes a water collection well 9 connected to the second shell 5 , and a recycling water pump 4 for extracting liquid in the water collection well 9 is connected to one side of the water collection well 9 .

[0042] During specific implementation, the water collection well 9 is provided to collect the tap water sprayed in the spray cleaning assembly, and the recycling water pump 4 is provided to extract the collected tap water for secondary utilization.

[0043] Working principle: When it is necessary to recover the waste heat of flue gas:

[0044] It enters the first-stage heat exchange component from the flue inlet, and the stainless steel heat exchanger 2 absorbs the heat of the flue gas and transfers the heat to the water cavity, heating the desalted water to boiling to produce a steam-water mixture. The steam-water mixture enters the steam drum 1, where it is separated. Qualified low-pressure saturated steam is output from the outlet on the steam drum 1 to the production unit for use; the saturated water is sent back to the inlet of the desalted water pipeline along the outlet.

[0045] After the flue gas absorbs heat and lowers its temperature, it becomes low-temperature flue gas and enters the second shell 5. It exchanges heat with low-temperature tap water through the fluoroplastic thin tube heat exchanger 8. The low-temperature tap water absorbs the residual heat of the flue gas and becomes medium-temperature hot water, which can be used for bathing, washing, etc., while further lowering the flue gas temperature. Finally, it is discharged into the atmosphere through the exhaust pipe; the water vapor in the flue gas condenses into water, flows down by gravity along the outer wall of the fluoroplastic thin tube heat exchanger 8, is enriched and enters the water collection well 9, and is transported to the reuse field for purification and utilization by the reuse water pump 4.

[0046] Considering that the flue gas temperature cannot be effectively reduced in the event of an accident of the primary heat exchange component, and the high-temperature flue gas may damage the second shell 5, an emergency exhaust flue is provided in front of the entrance of the second shell 5, and a flue gas damper valve 3 is provided on the flue. This valve is in a closed state during normal operation and is opened only in the event of an accident of the primary heat exchange component.

[0047] In order to ensure the heat exchange efficiency of the fluoroplastic thin tube heat exchanger 8 of the secondary heat exchange component, a spray device is set to wash its outer wall from time to time. The spray device consists of a spray pipe 6, a dosing mechanism 7 and a nozzle. The spray medium uses normal temperature tap water, and a certain concentration of sodium carbonate or sodium bicarbonate solution is injected into the dosing device. The solution is sprayed on the surface of the fluoroplastic thin tube heat exchanger 8 through the nozzle to clean the dust and dirt on its surface.

Claims

1. A medium and low temperature flue gas waste heat deep recovery device, characterized in that: include, A first heat exchange assembly comprises at least a first shell, wherein a plurality of stainless steel heat exchange elements (2) arranged at intervals and a transversely arranged partition are arranged in the first shell, wherein the partition divides the interior of the first shell into an independent smoke chamber and a water chamber; The second heat exchange component comprises at least a second shell (5), wherein a fluoroplastic thin tube heat exchange component (8) is arranged in the second shell (5); The first heat exchange component and the second heat exchange component are connected through a pipeline.

2. A medium and low temperature flue gas waste heat deep recovery device as claimed in claim 1, characterized in that: The first heat exchange component also includes a steam drum (1) arranged on one side of the first shell, one side of the steam drum (1) is connected to a water cavity opened in the first shell through a mounting pipe, and the steam drum (1) is respectively provided with an air outlet and a water outlet.

3. A medium and low temperature flue gas waste heat deep recovery device as claimed in claim 2, characterized in that: A desalted water connecting pipe is connected to one side of the first shell, one end of the desalted water connecting pipe extends into the water cavity, and one end of the air outlet is connected to the desalted water connecting pipe through a saturated water connecting pipe.

4. A medium and low temperature flue gas waste heat deep recovery device as claimed in claim 3, characterized in that: The second heat exchange component also includes a normal temperature tap water connection pipe connected to one side of the second shell (5), one end of the normal temperature tap water connection pipe extends into the second shell (5) and is connected to the water inlet end of the fluoroplastic capillary heat exchange component (8), and the water outlet end of the fluoroplastic capillary heat exchange component (8) extends to the outside of the second shell (5).

5. A medium and low temperature flue gas waste heat deep recovery device as claimed in claim 4, characterized in that: The second shell (5) also includes a spray cleaning assembly, which includes a spray water delivery pipe connected to one side of a normal temperature tap water connection pipe, one end of the spray water delivery pipe extends into the second shell (5) and is connected to a spray pipe (6), and a plurality of spray heads are arranged at equal intervals on the spray pipe (6), and the spray heads are located above the fluoroplastic capillary heat exchange component (8).

6. A medium and low temperature flue gas waste heat deep recovery device as claimed in claim 5, characterized in that: The spray cleaning component also includes a dosing mechanism (7) arranged on one side of the second shell (5), and the liquid outlet end of the dosing mechanism (7) is connected to the spray delivery pipe through the cleaning solution delivery pipe.

7. A medium and low temperature flue gas waste heat deep recovery device as claimed in claim 1, characterized in that: A clean water recovery component is also provided in the second shell (5), and the clean water recovery component comprises a water collection well (9) connected to the second shell (5), and one side of the water collection well (9) is connected to a recycling water pump (4) for extracting liquid in the water collection well (9).

8. A medium-low temperature flue gas waste heat deep recovery device according to any one of claims 1 to 7, characterized in that: It also comprises a protection component, which comprises an emergency exhaust duct connected to the pipeline, and a smoke damper valve (3) is arranged on the emergency exhaust duct, and the smoke damper valve (3) is used to open when the smoke temperature is high.

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