Two-phase flow phase change heat absorber

Abstract

The invention discloses a two-phase flow phase change heat absorber, comprising: a phase change heat absorber shell having an air inlet and an air outlet respectively arranged at the front and rear ends, a plurality of phase change heat absorbers are sequentially arranged at intervals from front to back along the gas flow direction inside the phase change heat absorber shell, and the structure of the phase change heat absorber comprises: an upper connecting tube and a lower connecting tube distributed up and down, a plurality of heat absorbing fin tubes arranged in rows at intervals from left to right are connected between the upper connecting tube and the lower connecting tube, and the upper and lower ends of each heat absorbing fin tube are respectively connected to the upper connecting tube and the lower connecting tube; the lower connecting tubes of all phase change heat absorbers are simultaneously connected to the lower liquid collecting tube, and the upper connecting tubes of all phase change heat absorbers are simultaneously connected to the upper gas collecting tube; a steam pipe with a valve is arranged on the upper gas collecting tube, and a thermocouple and a temperature regulator for detecting the temperature of the working medium steam in the upper gas collecting tube are arranged in the upper gas collecting tube. The invention has the advantages of energy saving and corrosion resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of energy-saving equipment in industries such as electric power, chemical industry and metallurgy, and in particular to a two-phase flow phase change heat absorber. Background Art

[0002] Boiler exhaust heat loss is one of the main heat losses in power station boilers. Exhaust heat loss accounts for the largest proportion of all heat losses in coal-fired boilers, accounting for more than 75% of the total heat loss of coal-fired boilers. The main factor leading to exhaust heat loss is the exhaust temperature. Under normal circumstances, for every 10°C increase in exhaust temperature, the exhaust heat loss increases by 0.6%-1%, and the heat consumption increases by 1.2%-2.4%. In addition, excessive exhaust temperature will not only seriously reduce the utilization rate of energy, but also greatly affect the subsequent desulfurization flue gas treatment system for flue gas treatment, reduce the dust removal efficiency of the dust collector, and increase the water consumption of the desulfurization tower. In order to more effectively utilize the flue gas waste heat and further improve the economy of the unit, it is necessary to develop a flue gas cooling device to make in-depth use of the flue gas waste heat and improve the utilization efficiency of the flue gas waste heat. Summary of the invention

[0003] The purpose of the present invention is to provide a two-phase flow phase change heat absorber which can effectively utilize the waste heat of flue gas.

[0004] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a two-phase flow phase change heat absorber, comprising: a phase change heat absorption shell having an air inlet and an air outlet respectively arranged at the front and rear ends, a plurality of phase change heat absorption sheets are sequentially arranged from front to back along the gas flow direction inside the phase change heat absorption shell, and the structure of the phase change heat absorption sheet comprises: an upper connecting tube and a lower connecting tube distributed up and down, a plurality of heat absorption fin tubes independently connected in parallel and arranged in rows at intervals from left to right are connected between the upper connecting tube and the lower connecting tube, and each heat absorption fin The upper and lower ends of the tube are connected to the upper connecting tube and the lower connecting tube respectively; the lower connecting tubes of all the phase change heat absorbing plates are connected to the lower liquid collecting tube at the same time, and a liquid inlet pipe with a valve is arranged on the lower liquid collecting tube, and the upper connecting tubes of all the phase change heat absorbing plates are connected to the upper gas collecting tube at the same time; a steam pipe with a valve is arranged on the upper gas collecting tube, and a thermocouple for detecting the temperature of the working fluid steam in the upper gas collecting tube and a temperature regulator that can adjust the temperature of the working fluid steam in the upper gas collecting tube according to the working fluid steam temperature fed back by the thermocouple are arranged in the upper gas collecting tube.

[0005] Furthermore, in the aforementioned two-phase flow phase change heat absorber, the structure of the temperature regulator includes: a controller, a temperature regulating water source, a regulating pump, and a temperature regulating tube passing through the upper connecting pipe and the upper gas collecting pipe, the temperature regulating tube is connected to the temperature regulating water source through the regulating pump, and the controller is also electrically connected to the regulating pump and a thermocouple for detecting the temperature of the working fluid vapor in the upper gas collecting pipe.

[0006] Furthermore, in the aforementioned two-phase flow phase change heat absorber, the diameter of each upper connecting pipe gradually decreases along the gas flow direction, and the temperature regulating pipe is arranged in the two frontmost upper connecting pipes.

[0007] Furthermore, in the aforementioned two-phase flow phase change heat absorber, a drain pipe with a valve, a liquid replenishing pipe with a valve, and a thermocouple for detecting the liquid temperature in the lower liquid collecting pipe are arranged on the lower liquid collecting pipe, and a vent pipe with a valve is arranged on the upper gas collecting pipe.

[0008] Furthermore, in the aforementioned two-phase flow phase change heat absorber, the phase change heat absorption shell is assembled from a base frame, side plates, a top plate, and reinforced angle steels.

[0009] Furthermore, in the aforementioned two-phase flow phase change heat absorber, anti-wear tiles are provided on the smoke facing surface of each heat absorbing fin tube in the first row of phase change heat absorbing sheets along the gas flow direction in the phase change heat absorbing shell.

[0010] Furthermore, in the aforementioned two-phase flow phase change heat absorber, the specific installation structure of the anti-wear shoe includes: a clip with a U-shaped bayonet is provided on the inner side of the anti-wear shoe, and the anti-wear shoe is detachably installed on the heat absorbing fin tube by buckling the U-shaped bayonet of the clip on the heat absorbing fin tube.

[0011] Furthermore, in the aforementioned two-phase flow phase change heat absorber, a guide plate for guiding the flue gas to flow toward the phase change heat absorber sheet is provided on the smoke-facing side of the phase change heat absorber shell.

[0012] Furthermore, in the aforementioned two-phase flow phase change heat absorber, a collecting pipe guard plate for protecting the corresponding connecting pipes is arranged around the outside of the upper connecting pipe and the lower connecting pipe.

[0013] Furthermore, in the aforementioned two-phase flow phase change heat absorber, wherein: the phase change heat absorber whose heat absorbing fin tubes are all left-handed fin tubes is defined as a left-handed phase change heat absorber, and the phase change heat absorber whose heat absorbing fin tubes are all right-handed fin tubes is defined as a right-handed phase change heat absorber, and along the gas flow direction, the left-handed phase change heat absorber and the right-handed phase change heat absorber are arranged alternately front and back in the phase change heat absorber shell.

[0014] Through the implementation of the above technical solution, the beneficial effects of the present invention are:

[0015] (1) Reliable: The energy-saving system can be controlled independently without affecting the normal operation of the boiler;

[0016] (2) Energy saving: It can effectively utilize the waste heat of flue gas, reduce energy consumption, increase the steam production rate per ton of coal, increase boiler output, and steadily increase the thermal efficiency of the boiler by more than 1.5%;

[0017] (3) Water saving: While recovering heat energy, it can also reduce the exhaust gas temperature of the post-stage desulfurization system, thus saving a large amount of water used in the desulfurization process;

[0018] (4) Anti-corrosion: It can significantly reduce the exhaust gas temperature while maintaining the wall temperature of the entire heat exchange equipment at a higher temperature level, so that the wall temperature of the entire heat exchange equipment is always about 10°C above the acid dew point, preventing acid dew corrosion and thus eliminating leakage hazards; it not only maximizes the thermal efficiency of the heat exchange equipment, but also avoids low-temperature corrosion and ash blockage caused by condensation;

[0019] (6) Emission reduction: Saving energy consumption is the biggest emission reduction. While reducing CO2 and NOX emissions, it also effectively reduces dust emissions;

[0020] (7) High heat transfer efficiency, small size, light weight, no disadvantages such as heat carrier circulation pump, low operating pressure in the pipe, complex system and small application range. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the structural principle of a two-phase flow phase change heat absorber described in the present invention.

[0022] Figure 2 for Figure 1 Schematic diagram of the structure after the bell mouth is hidden in the left view.

[0023] Figure 3 for Figure 2 Schematic diagram of the structure from a top-down perspective.

[0024] Figure 4 for Figure 3 Schematic diagram of the structure of the phase change heat absorber shown in .

[0025] Figure 5 for Figure 4 Schematic diagram of the structure from the left view direction.

[0026] Figure 6 for Figure 5 An enlarged schematic diagram of site B is shown in FIG.

[0027] Figure 7 for Figure 6 Schematic diagram of the positional relationship between the heat-absorbing fin tube and the anti-wear shoe as seen from above. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0029] like Figure 1, Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 As shown, the two-phase flow phase change heat absorber comprises: a phase change heat absorption shell 3 with an air inlet 1 and an air outlet 2 respectively arranged at the front and rear ends, and a bell mouth 17 is respectively arranged at the air inlet 1 and the air outlet 2 of the phase change heat absorption shell 3, and a plurality of phase change heat absorption sheets 4 are sequentially arranged along the gas flow direction from front to back in the interior of the phase change heat absorption shell 3, and the structure of the phase change heat absorption sheet 4 comprises: an upper connecting tube 5 and a lower connecting tube 6 distributed up and down, and a plurality of heat absorption fin tubes 7 arranged in rows at intervals from left to right are connected between the upper connecting tube 5 and the lower connecting tube 6, and the upper of each heat absorption fin tube 7 The lower two ends are connected to the upper connecting tube 5 and the lower connecting tube 6 respectively; the lower connecting tubes 6 of all phase change heat absorbing sheets 4 are simultaneously connected to the lower liquid collecting tube 8, and the lower liquid collecting tube 8 is provided with a liquid inlet pipe 9 with a valve, and the upper connecting tubes 5 of all phase change heat absorbing sheets 4 are simultaneously connected to the upper gas collecting tube 10; a steam pipe 11 with a valve is provided on the upper gas collecting tube 10, and a first thermocouple 12 for detecting the temperature of the working fluid vapor in the upper gas collecting tube 10 and a temperature regulator that can adjust the temperature of the working fluid vapor in the upper gas collecting tube 10 according to the working fluid vapor temperature fed back by the first thermocouple 12 are provided in the upper gas collecting tube 10;

[0030] In this embodiment, the structure of the temperature regulator includes: a controller 13, a temperature regulating water source 14, a regulating pump 15, and a temperature regulating pipe 16 passing through the upper connecting pipe 5 and the upper gas collecting pipe 10. The temperature regulating pipe 16 is connected to the temperature regulating water source 14 through the regulating pump 15. The controller 13 is also electrically connected to the regulating pump 15 and the first thermocouple 12 for detecting the temperature of the working fluid vapor in the upper gas collecting pipe 10. The controller 13 automatically controls and adjusts the flow rate of water flowing through the temperature regulating pipe 16 through the regulating pump 15 according to the temperature of the working fluid vapor in the upper gas collecting pipe 10 fed back by the first thermocouple 12, so that the working fluid vapor in the upper gas collecting pipe 10 exchanges heat with the temperature regulating pipe 16, thereby adjusting the temperature of the working fluid vapor in the upper gas collecting pipe 10, and ensuring that the temperature of the working fluid vapor discharged into the downstream process meets the requirements of the downstream process; in this embodiment, the diameter of each upper connecting pipe 5 gradually decreases along the gas flow direction, and the temperature regulating pipe is passed through the two upper connecting pipes at the front end, so as to ensure that the phase change speed is more balanced;

[0031] In this embodiment, an emptying pipe 18 with a valve, a liquid replenishing pipe 19 with a valve, and a second thermocouple 20 for detecting the liquid temperature in the lower liquid collecting pipe 8 are provided on the lower liquid collecting pipe 8, and an air venting pipe 21 with a valve is provided on the upper gas collecting pipe 10. The emptying pipe is used to drain the liquid in the lower liquid collecting pipe during maintenance, and the liquid in the lower liquid collecting pipe can be replenished in real time through the liquid replenishing pipe. The liquid temperature in the lower liquid collecting pipe is detected in real time through the second thermocouple, and the pressure in the upper gas collecting pipe can be adjusted through the air venting pipe, thereby further improving the use stability and safety of the equipment;

[0032] In this embodiment, the phase change heat absorption shell 3 is assembled from a base frame, a side plate, a top plate, and a reinforcing angle steel, and has a simple structure and is easy to assemble; in this embodiment, an inspection door 22 is provided on the side plate of the phase change heat absorption shell 3, which is convenient for inspection and maintenance;

[0033] In this embodiment, the smoke-facing surface of each heat-absorbing fin tube 7 in the first row of phase-changing heat-absorbing sheets 4 along the gas flow direction in the phase-changing heat-absorbing shell 3 is provided with an anti-wear tile 23, which can protect the heat-absorbing fin tube and prevent the heat-absorbing fin tube from being directly eroded and damaged by the smoke, thereby extending the service life of the equipment; in this embodiment, the specific installation structure of the anti-wear tile 23 includes: a clip 25 with a U-shaped bayonet is provided on the inner side of the anti-wear tile 23, and the anti-wear tile 23 is detachably installed on the heat-absorbing fin tube by buckling the U-shaped bayonet of the clip 25 on the heat-absorbing fin tube. This makes it easy to disassemble and replace the anti-wear tile, thereby improving the installation and maintenance efficiency;

[0034] In this embodiment, a guide plate 24 for guiding the flue gas to flow toward the phase-change heat absorbing sheet 4 is provided on the smoke-facing side of the phase-change heat absorbing shell 3; in this embodiment, a collecting tube guard plate for protecting the corresponding connecting tubes is provided around the outside of the upper connecting tube 5 and the lower connecting tube 6; in this embodiment, the phase-change heat absorbing sheet whose heat absorbing fin tubes are all left-handed fin tubes is defined as a left-handed phase-change heat absorbing sheet, and the phase-change heat absorbing sheet whose heat absorbing fin tubes are all right-handed fin tubes is defined as a right-handed phase-change heat absorbing sheet. Along the gas flow direction, the left-handed phase-change heat absorbing sheet and the right-handed phase-change heat absorbing sheet are arranged alternately front and back in the phase-change heat absorbing shell, so that heat exchange with the flue gas can be better performed, thereby improving the heat exchange efficiency;

[0035] During installation, the air inlet 1 of the phase change heat absorber is connected to the smoke exhaust pipe of the boiler through the smoke inlet flue, and the air outlet 2 of the phase change heat absorber is connected to the dust collector;

[0036] During operation, the liquid working medium (usually water) in each heat-absorbing fin tube 7 of the phase change heat absorber will exchange heat with the superheated flue gas (the flue gas temperature is 160°C) discharged from the boiler, and the superheated flue gas discharged from the boiler will be cooled down. After the heat exchange, the flue gas temperature will be reduced to 115°C and discharged. After the heat exchange, the liquid working medium in each heat-absorbing fin tube 7 of the phase change heat absorber will absorb heat, heat up and evaporate to form working medium vapor. The working medium vapor enters the corresponding upper connecting tube 5 through the corresponding heat-absorbing fin tube 7 in turn. The working medium vapor in each upper connecting tube 5 is discharged. The gas is then collected in the upper gas collecting pipe 10, and the working fluid steam in the upper gas collecting pipe 10 is discharged into the downstream process through the steam pipe 11; during operation, the controller 13 can automatically control the flow rate of water flowing through the temperature regulating pipe 16 through the regulating pump 15 according to the temperature of the working fluid steam in the upper gas collecting pipe 10 fed back by the first thermocouple 12, so that the working fluid steam in the upper gas collecting pipe 10 exchanges heat with the temperature regulating pipe 16, thereby adjusting the temperature of the working fluid steam in the upper gas collecting pipe 10, ensuring that the temperature of the working fluid steam discharged into the downstream meets the requirements of the downstream process.

[0037] The advantages of the present invention are:

[0038] (1) Reliable: The energy-saving system can be controlled independently without affecting the normal operation of the boiler;

[0039] (2) Energy saving: It can effectively utilize the waste heat of flue gas, reduce energy consumption, increase the steam production rate per ton of coal, increase boiler output, and steadily increase the thermal efficiency of the boiler by more than 1.5%;

[0040] (3) Water saving: While recovering heat energy, it can also reduce the exhaust gas temperature of the post-stage desulfurization system, thus saving a large amount of water used in the desulfurization process;

[0041] (4) Anti-corrosion: It can significantly reduce the exhaust gas temperature while maintaining the wall temperature of the entire heat exchange equipment at a higher temperature level, so that the wall temperature of the entire heat exchange equipment is always about 10°C above the acid dew point, preventing acid dew corrosion and thus eliminating leakage hazards; it not only maximizes the thermal efficiency of the heat exchange equipment, but also avoids low-temperature corrosion and ash blockage caused by condensation;

[0042] (6) Emission reduction: Saving energy consumption is the biggest emission reduction. While reducing CO2 and NOX emissions, it also effectively reduces dust emissions;

[0043] (7) High heat transfer efficiency, small size, light weight, no disadvantages such as heat carrier circulation pump, low operating pressure in the pipe, complex system and small application range.

[0044] The above description is only a preferred embodiment of the present invention and does not constitute any other form of limitation to the present invention. Any modification or equivalent change made based on the technical essence of the present invention still falls within the scope of protection required by the present invention.

Claims

1. A two-phase flow phase change heat absorber, characterized in that: include: A phase-change heat-absorbing shell is provided with an air inlet and an air outlet at the front and rear ends respectively, and a plurality of phase-change heat-absorbing sheets are arranged in sequence from front to back along the gas flow direction inside the phase-change heat-absorbing shell, and the structure of the phase-change heat-absorbing sheet comprises: an upper connecting tube and a lower connecting tube which are distributed up and down, and a plurality of heat-absorbing fin tubes which are independently connected in parallel and arranged in rows at intervals from left to right are connected between the upper connecting tube and the lower connecting tube, and the upper and lower ends of each heat-absorbing fin tube are connected to the upper connecting tube and the lower connecting tube respectively; the lower connecting tubes of all the phase-change heat-absorbing sheets are connected to the lower liquid collecting tube at the same time, and the lower liquid collecting tube is provided with a liquid inlet pipe with a valve, and the upper connecting tubes of all the phase-change heat-absorbing sheets are connected to the upper gas collecting tube at the same time; a steam pipe with a valve is provided on the upper gas collecting tube, and a thermocouple for detecting the temperature of the working medium steam in the upper gas collecting tube is provided in the upper gas collecting tube, and a thermocouple which can detect the temperature of the working medium steam in the upper gas collecting tube according to the temperature of the thermocouple The temperature regulator is a temperature regulator for regulating the temperature of the working fluid vapor in the upper gas collecting pipe by feedback of the working fluid vapor temperature; the structure of the temperature regulator includes: a controller, a temperature regulating water source, a regulating pump, and a temperature regulating pipe inserted in the upper interconnecting pipe and the upper gas collecting pipe, the temperature regulating pipe is connected to the temperature regulating water source through the regulating pump, and the controller is electrically connected to the regulating pump and a thermocouple for detecting the temperature of the working fluid vapor in the upper gas collecting pipe at the same time; the diameter of each upper interconnecting pipe gradually decreases along the gas flow direction, and the temperature regulating pipe is inserted in the two upper interconnecting pipes at the front end; an emptying pipe with a valve, a liquid replenishing pipe with a valve, and a thermocouple for detecting the liquid temperature in the lower liquid collecting pipe are arranged on the lower collecting pipe, and a venting pipe with a valve is arranged on the upper gas collecting pipe; anti-wear tiles are arranged on the smoke facing surface of each heat absorbing fin tube in the first row of phase change heat absorbing plates along the gas flow direction in the phase change heat absorbing shell.

2. A two-phase flow phase change heat absorber according to claim 1, characterized in that: The phase change heat absorption shell is assembled from a base frame, side plates, a top plate, and reinforced angle steels.

3. A two-phase flow phase change heat absorber according to claim 1, characterized in that: The specific installation structure of the anti-wear shoe includes: a clip with a U-shaped bayonet is arranged on the inner side of the anti-wear shoe, and the anti-wear shoe is detachably installed on the heat absorbing fin tube by buckling the U-shaped bayonet of the clip on the heat absorbing fin tube.

4. A two-phase flow phase change heat absorber according to claim 1, characterized in that: A guide plate for guiding the smoke flow toward the phase change heat absorption sheet is arranged on the smoke-facing side of the phase change heat absorption shell.

5. The two-phase flow phase change heat absorber according to claim 1, characterized in that: The outer parts of the upper connecting pipe and the lower connecting pipe are surrounded by collecting pipe guard plates for protecting the corresponding connecting pipes.

6. A two-phase flow phase change heat absorber according to claim 1, characterized in that: The phase change heat absorber whose heat absorbing fin tubes are all left-handed fin tubes is defined as left-handed phase change heat absorber, and the phase change heat absorber whose heat absorbing fin tubes are all right-handed fin tubes is defined as right-handed phase change heat absorber. Along the gas flow direction, the left-handed phase change heat absorber and the right-handed phase change heat absorber are arranged alternately front and back in the phase change heat absorption shell.

Images