Integrated system for sulfur-containing flue gas waste heat efficient recovery and combustion-supporting air
By combining flue gas pretreatment, waste heat depth recovery and desulfurization synergistic units, the cascade utilization of sulfur-containing flue gas waste heat and efficient preheating of combustion-assisted air are achieved, which solves the problems of low flue gas waste heat recovery efficiency and equipment corrosion, and improves the energy efficiency and environmental performance of the system.
Patent Information
- Application Number
- CN202510643229.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-19
- Publication Date
- 2025-07-08
AI Technical Summary
In the prior art, the sulfur-containing flue gas waste heat recovery system is independent of the combustion-assisted air system, has low efficiency and the equipment is prone to corrosion, resulting in energy waste and additional energy consumption.
The deep combination of the flue gas pretreatment unit, the waste heat depth recovery unit and the desulfurization coordination unit is adopted to heat the combustion air step by step by step using the flue gas waste heat, and the flow rate of the lithium bromide solution is controlled by an electric regulating valve to prevent acid dew point corrosion.
It realizes efficient recycling of waste heat of flue gas and preheating of combustion-assisted air, reduces energy consumption and pollutant emissions, optimizes the combustion process, and prevents equipment corrosion.
Smart Images
Figure CN120274279A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of waste heat recovery and utilization, and particularly to an integrated system for efficient recovery of waste heat from sulfur-containing flue gas and combustion-supporting air. Background Art
[0002] In industrial fields such as metallurgy, chemical engineering, and electric power, a large amount of sulfur-containing flue gas is generated. It has a high temperature and considerable heat energy. Direct emission will cause serious energy waste. In the past, the flue gas waste heat recovery system and the combustion-supporting air system were independent of each other. When recovering waste heat, traditional technologies used heat exchangers to recover heat, with low efficiency. Moreover, sulfur-containing flue gas has strong corrosiveness, and the equipment is prone to damage and fouling, affecting recovery and service life. In terms of the supply of combustion-supporting air, without preheating with the waste heat of the flue gas, additional energy consumption is required to heat the combustion-supporting air for combustion.
[0003] From the perspectives of environmental protection and energy conservation, improving the waste heat recovery efficiency of sulfur-containing flue gas can not only reduce the energy consumption of enterprises and carbon emissions, but also use the recovered heat to preheat the combustion-supporting air, optimize combustion, reduce fuel consumption and pollutant emissions, which is in line with current environmental protection regulations and the trend of energy conservation and emission reduction.
[0004] Based on the above problems, the present invention proposes an integrated system for efficient recovery of waste heat from sulfur-containing flue gas and combustion-supporting air. Summary of the Invention
[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and provide an integrated system for efficient recovery of waste heat from sulfur-containing flue gas and combustion-supporting air. By deeply integrating the flue gas pretreatment unit, the deep waste heat recovery unit of the flue gas, and the flue gas desulfurization cooperation unit, the waste heat of the factory flue gas is utilized in a cascade manner, the combustion-supporting air is heated in a cascade manner, and the flow rate of the lithium bromide solution is controlled by an electric control valve to adapt to different acid dew points and other methods to efficiently utilize the waste heat of the flue gas and prevent acid dew point corrosion of heat exchange equipment.
[0006] To achieve the purpose of the present invention, the technical solution adopted by the present invention is as follows: The present invention discloses an integrated system for efficient recovery of waste heat from sulfur-containing flue gas and combustion-supporting air, including a flue gas pretreatment unit and a deep waste heat recovery unit. The flue gas pretreatment unit includes a flue gas-oil heat exchanger, an oil pipeline circulation pump, and an air-oil heat exchanger. The left end of the flue gas-oil heat exchanger is provided with an air inlet for untreated flue gas to enter. The two ends of the outer wall of the flue gas-oil heat exchanger are respectively provided with a flue gas-oil heat exchanger oil outlet and a flue gas-oil heat exchanger inlet. The two ends of the outer wall of the air-oil heat exchanger are respectively provided with an air-oil heat exchanger oil inlet and an air-oil heat exchanger oil outlet. The flue gas-oil heat exchanger oil outlet is connected to the air-oil heat exchanger oil inlet through the oil pipeline circulation pump, and the air-oil heat exchanger oil outlet is connected to the flue gas-oil heat exchanger inlet. The air outlet at the right end of the flue gas-oil heat exchanger is connected to the deep waste heat recovery unit.
[0007] The waste heat deep recovery unit includes a flue gas lithium bromide heat exchanger, a first circulation pump, a gas-liquid separation device, an electric control valve, a condensate water tank, a condensate water heat exchanger, a steam-air heat exchanger, and a flue gas temperature regulator. The air inlet at the left end of the flue gas lithium bromide heat exchanger is communicated with the air outlet at the right end of the flue gas-oil heat exchanger. At both ends of the outer wall of the flue gas lithium bromide heat exchanger, there are respectively a lithium bromide solution inlet of the flue gas lithium bromide heat exchanger and a gas-liquid outlet of the heat exchanger of the flue gas lithium bromide heat exchanger. The gas-liquid outlet of the heat exchanger of the flue gas lithium bromide heat exchanger is communicated with the gas-liquid separation device through the first circulation pump. One side outlet of the gas-liquid separation device is communicated with the lithium bromide solution inlet of the flue gas lithium bromide heat exchanger through the flue gas temperature regulator. The other side outlet of the gas-liquid separation device is communicated with the water vapor inlet of the steam-air heat exchanger on one side of the outer wall of the steam-air heat exchanger. The liquid outlet of the steam-air heat exchanger on the other side of the outer wall of the steam-air heat exchanger is communicated with one side inlet of the condensate water tank. One side outlet of the condensate water tank is communicated with one side inlet of the outer wall of the condensate water heat exchanger. The outlet on the other side of the outer wall of the condensate water heat exchanger is communicated with the other side inlet of the condensate water tank through the second circulation pump. The other side outlet of the condensate water tank is communicated with the flue gas temperature regulator.
[0008] The condensate water tank is communicated with the flue gas temperature regulator through an electric control valve.
[0009] It further includes a desulfurization cooperation unit. The desulfurization cooperation unit includes an air-liquid heat exchanger, a desulfurization tower, a double-liquid heat exchanger, and a third circulation pump. The air outlet at the right end of the flue gas lithium bromide heat exchanger is communicated with the air inlet below the left side wall of the desulfurization tower. An air outlet is provided below the right side wall of the desulfurization tower. The double-liquid heat exchanger is provided at the bottom of the inner cavity of the desulfurization tower. The double-liquid heat exchanger outlet of the double-liquid heat exchanger is communicated with the liquid inlet of the air-liquid heat exchanger on one side of the outer wall of the air-liquid heat exchanger. The liquid outlet of the air-liquid heat exchanger on the other side of the outer wall of the air-liquid heat exchanger is communicated with the double-liquid heat exchanger inlet of the double-liquid heat exchanger through the third circulation pump.
[0010] The air-liquid heat exchanger, the condensate water heat exchanger, the steam-air heat exchanger, and the air-oil heat exchanger are connected in sequence. The inlet at the left end of the air-liquid heat exchanger is communicated with the output end of the fan.
[0011] The flue gas lithium bromide heat exchanger includes a shell, a tube body, tube sheets, baffle plates and a tube bundle. The shell is a hollow cylindrical structure with an open right end. The tube body is a tubular structure with an end cover at its right end. The left end opening of the tube body is connected to the right end opening of the shell through the tube sheet. A diversion partition is horizontally provided in the middle of the shell. A lithium bromide solution inlet of the flue gas lithium bromide heat exchanger and a gas-liquid outlet of the heat exchanger are respectively provided at the top and bottom of the shell. An air inlet and an air outlet are respectively provided at the left end of the top and the right end of the bottom of the tube body. The tube bundle is in a U-shaped structure. A number of tube bundle holes for fixing both ends of the tube bundle are respectively provided above and below the outer wall of the tube sheet. The baffle plate is in a three-quarter circular structure. A through hole for the tube bundle to pass through is provided on the outer wall of the baffle plate. The baffle plates are alternately arranged above and below the inner wall of the tube body along the length direction of the tube body, and the baffle plates are in close contact with the inner wall of the tube body.
[0012] The distance between the baffle plates gradually decreases from the air inlet to the air outlet.
[0013] A quick tightening mechanism capable of quickly tightening the tube bundle is provided on the outer wall of the baffle plate. The quick tightening mechanism includes a first limiting ring, a second limiting ring, a tightening ring, an ear plate, a locking bolt and a locking nut. The first limiting ring, the tightening ring and the second limiting ring are axially sleeved on the outside of the tube bundle in sequence from one end close to the outer wall of the baffle plate to the outside. The inner end of the first limiting ring is fixed on the outer wall of the baffle plate. The cross section of the tightening ring is an isosceles trapezoid structure with a width gradually increasing from the outside to the inside. Oblique rings for clamping the outer walls on both sides of the tightening ring are respectively provided at the outer end of the first limiting ring and the inner end of the second limiting ring. The slope of the oblique ring is the same as the slopes of the two side walls of the tightening ring. A number of the ear plates are spaced on the outer wall of the oblique ring. A bolt hole for the locking bolt to pass through is provided axially on the ear plate. The locking bolt passes through the bolt hole and is threadedly connected with the locking nut.
[0014] The beneficial effects of the present invention are as follows: (1) By deeply combining the flue gas pretreatment unit, the flue gas waste heat deep recovery unit and the flue gas desulfurization cooperation unit, the present invention adopts cascade utilization of the flue gas waste heat in the factory, cascade heating of the combustion-supporting air, and controls the flow rate of the lithium bromide solution by an electric control valve to adapt to different acid dew points and other methods, so as to efficiently utilize the flue gas waste heat and prevent acid dew point corrosion of the heat exchange equipment. (2) The present invention can realize cascade utilization of the flue gas waste heat. Through three heat exchange cycles including a flue gas-oil heat exchange cycle formed by a flue gas oil heat exchanger and an air oil heat exchanger, a flue gas-lithium bromide heat exchange cycle formed by a flue gas lithium bromide heat exchanger, and a desulfurization liquid-water heat exchange cycle composed of a desulfurization tower and a double-fluid heat exchanger, the flue gas waste heat is cascade recovered to realize efficient recovery of the flue gas waste heat. (3) In the present invention, an electric control valve is used to control the flow rate of condensate, thereby regulating the temperature of the flue gas outlet and controlling it above 100 °C to prevent the heat exchanger wall from being corroded; (4) The heat recovered from the four - stage recovery of the flue gas waste heat is used to cascade - heat the combustion - supporting air through the heat exchanger, realizing the efficient utilization of the flue gas waste heat. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 is a schematic structural diagram of the present invention; Figure 2 is a schematic cross - sectional view of the flue gas lithium bromide heat exchanger of the present invention; Figure 3 is a schematic partial structural diagram of the flue gas lithium bromide heat exchanger of the present invention; Figure 4 is a schematic structural diagram of the quick - tightening mechanism of the present invention.
[0016] In the drawings, 1 is the air - liquid heat exchanger, 2 is the condensate heat exchanger, 3 is the steam - air heat exchanger, 4 is the air - oil heat exchanger, 5 is the flue gas - oil heat exchanger, 6 is the flue gas lithium bromide heat exchanger, 7 is the desulfurization tower, 8 is the fan, 9 is the double - liquid heat exchanger, 10 is the oil pipeline circulation pump, 11 is the condensate tank, 12 is the flue gas temperature regulator, 13 is the third circulation pump, 14 is the electric control valve, 15 is the gas - liquid separation device, 16 is the first circulation pump, 17 is the second circulation pump, 18 is the quick - tightening mechanism; S1 is the liquid inlet of the air - liquid heat exchanger, S2 is the liquid outlet of the air - liquid heat exchanger, S3 is the inlet of the double - liquid heat exchanger, S4 is the outlet of the double - liquid heat exchanger, S5 is the liquid outlet of the steam - air heat exchanger, S6 is the water vapor inlet of the steam - air heat exchanger, S7 is the lithium bromide solution inlet of the flue gas lithium bromide heat exchanger, S8 is the gas - liquid outlet of the heat exchanger of the flue gas lithium bromide heat exchanger, S9 is the oil inlet of the air - oil heat exchanger, S10 is the oil outlet of the air - oil heat exchanger, S11 is the oil outlet of the flue gas - oil heat exchanger, S12 is the inlet of the flue gas - oil heat exchanger; 61 is the housing, 62 is the tube body, 63 is the tube sheet, 64 is the baffle plate, 65 is the tube bundle, 66 is the end cover, 67 is the flow - dividing partition plate, 181 is the first limit ring, 182 is the second limit ring, 183 is the tightening ring, 184 is the ear plate, 185 is the locking bolt, 186 is the locking nut, 187 is the inclined ring. DETAILED DESCRIPTION OF THE INVENTION
[0017] The present invention will be further described below: Please refer to Figures 1-4 , The present invention discloses an integrated system for efficient recovery of waste heat from sulfur-containing flue gas and combustion-supporting air, which includes a flue gas pretreatment unit and a deep waste heat recovery unit. The flue gas pretreatment unit includes a flue gas-oil heat exchanger 5, an oil pipeline circulation pump 10, and an air-oil heat exchanger 4. An air inlet for untreated flue gas is provided at the left end of the flue gas-oil heat exchanger 5. At both ends of the outer wall of the flue gas-oil heat exchanger 5, there are respectively a flue gas-oil heat exchanger oil outlet S11 and a flue gas-oil heat exchanger inlet S12. At both ends of the outer wall of the air-oil heat exchanger 4, there are respectively an air-oil heat exchanger oil inlet S9 and an air-oil heat exchanger oil outlet S10. The flue gas-oil heat exchanger oil outlet S11 is communicated with the air-oil heat exchanger oil inlet S9 through the oil pipeline circulation pump 10, and the air-oil heat exchanger oil outlet S10 is communicated with the flue gas-oil heat exchanger inlet S12. The gas outlet at the right end of the flue gas-oil heat exchanger 5 is connected to the deep waste heat recovery unit. By deeply integrating the flue gas pretreatment unit, the deep flue gas waste heat recovery unit, and the flue gas desulfurization cooperation unit, the waste heat of the factory flue gas is utilized in a cascade manner, the combustion-supporting air is heated in a cascade manner, and the flow rate of the lithium bromide solution is controlled by an electric control valve to adapt to different acid dew points and other methods, so as to efficiently utilize the waste heat of the flue gas and prevent the acid dew point from corroding the heat exchange equipment.
[0018] Further, the deep waste heat recovery unit includes a flue gas-lithium bromide heat exchanger 6, a first circulation pump 16, a gas-liquid separation device 15, an electric control valve 14, a condensate water tank 11, a condensate water heat exchanger 2, a steam-air heat exchanger 3, and a flue gas temperature regulator 12. The air inlet at the left end of the flue gas-lithium bromide heat exchanger 6 is communicated with the gas outlet at the right end of the flue gas-oil heat exchanger 5. At both ends of the outer wall of the flue gas-lithium bromide heat exchanger 6, there are respectively a flue gas-lithium bromide heat exchanger lithium bromide solution inlet S7 and a flue gas-lithium bromide heat exchanger heat exchanger gas-liquid outlet S8. The flue gas-lithium bromide heat exchanger heat exchanger gas-liquid outlet S8 is communicated with the gas-liquid separation device 15 through the first circulation pump 16. One side outlet of the gas-liquid separation device 15 is communicated with the flue gas-lithium bromide heat exchanger lithium bromide solution inlet S7 through the flue gas temperature regulator 12. The other side outlet of the gas-liquid separation device 15 is communicated with the steam-air heat exchanger steam-water vapor inlet S6 on one side of the outer wall of the steam-air heat exchanger 3. The steam-air heat exchanger liquid outlet S5 on the other side of the outer wall of the steam-air heat exchanger 3 is communicated with one side inlet of the condensate water tank 11. One side outlet of the condensate water tank 11 is communicated with the inlet on one side of the outer wall of the condensate water heat exchanger 2. The outlet on the other side of the outer wall of the condensate water heat exchanger 2 is communicated with the other side inlet of the condensate water tank 11 through a second circulation pump 17. The other side outlet of the condensate water tank 11 is communicated with the flue gas temperature regulator 12. Working process of the waste heat deep recovery unit: The inlet of the flue gas lithium bromide heat exchanger 6 is fed with the flue gas after the first heat exchange treatment for the second heat exchange treatment. The sulfur-containing flue gas releases heat in the flue gas lithium bromide heat exchanger 6, and the lithium bromide aqueous solution absorbs heat in the flue gas lithium bromide heat exchanger 6, generating a two-phase flow mixture of steam and concentrated lithium bromide solution, which flows into the gas-liquid separation device 15 to separate the lithium bromide solution and steam. The lithium bromide solution flows into the flue gas temperature regulator 12 through a pipeline, and the steam enters the steam-air heat exchanger 3. The steam exchanges heat with the combustion-supporting air, cools into condensed water after heat exchange, and enters the condensed water tank 11 through the inlet of the condensed water tank. After the condensed water flows into the condensed water tank 11, it exchanges heat with the condensed water heat exchanger 2 through the inlet S13 of the condensed water heat exchanger to heat the liquid in the condensed water heat exchanger 2. After the liquid is heated, it flows into the steam-air heat exchanger 3 through the outlet S14 of the condensed water heat exchanger under the second action of the second circulation pump 17 to heat the combustion-supporting air, and the liquid flows back to the condensed water heat exchanger 2 after heat exchange. The condensed water flows out through the outlet of the condensed water tank 11 after heat exchange, and the condensed water enters the flue gas temperature regulator 12.
[0019] Furthermore, the condensed water tank 11 is connected to the flue gas temperature regulator 12 through an electric control valve 14. By adjusting the flow rate of the condensed water, the inlet concentration of the lithium bromide aqueous solution in the flue gas lithium bromide heat exchanger 6 is controlled, and thus the flue gas outlet temperature is controlled. The flow rate of the condensed water is controlled by the electric control valve 14, and then the flue gas outlet temperature is adjusted and controlled above 100 °C to prevent the heat exchanger wall surface from being corroded.
[0020] Furthermore, it also includes a desulfurization cooperation unit. The desulfurization cooperation unit includes an air-liquid heat exchanger 1, a desulfurization tower 7, a double-liquid heat exchanger 9, and a third circulation pump 13. The outlet of the right end of the flue gas lithium bromide heat exchanger 6 is connected to the inlet at the lower part of the left side wall of the desulfurization tower 7, and the outlet at the lower part of the right side wall of the desulfurization tower 7 is provided with an outlet; the double-liquid heat exchanger 9 is arranged at the bottom of the inner cavity of the desulfurization tower 7, and the double-liquid heat exchanger outlet S4 of the double-liquid heat exchanger 9 is connected to the air-liquid heat exchanger liquid inlet S1 on one side of the outer wall of the air-liquid heat exchanger 1. The air-liquid heat exchanger liquid outlet S2 on the other side of the outer wall of the air-liquid heat exchanger 1 is connected to the double-liquid heat exchanger inlet S3 of the double-liquid heat exchanger 9 through the third circulation pump 13.
[0021] Working process of the desulfurization collaborative unit: The sulfur-containing flue gas passing through the flue gas lithium bromide heat exchanger 6 flows into the desulfurization tower 7 from the inlet below the left side wall of the desulfurization tower 7, and is discharged through the flue gas pipeline below the right side wall of the desulfurization tower 7 after being treated by the desulfurization spray in the desulfurization tower 7. The spray liquid participating in the desulfurization treatment remains at the bottom of the desulfurization tower 7 and heats the water in the heat exchanger through the double-fluid heat exchanger 9. The water after heat exchange flows through the air-liquid heat exchanger 1 under the action of the third circulation pump 13 to heat the combustion-supporting air in the air-liquid heat exchanger 1. The water that has completed the heat exchange flows back to the double-fluid heat exchanger 9 at the bottom of the desulfurization tower 7 to form a loop. By deeply integrating the cascade flue gas waste heat recovery system with the flue gas desulfurization system, the waste heat of the factory flue gas is utilized in a cascade manner, and the combustion-supporting air is heated in a cascade manner. The electric control valve controls the flow rate of the lithium bromide solution to adapt to different acid dew points and other methods to efficiently utilize the flue gas waste heat and prevent acid dew point corrosion of heat exchange equipment.
[0022] Furthermore, the air-liquid heat exchanger 1, the condensate heat exchanger 2, the steam-air heat exchanger 3, and the air-oil heat exchanger 4 are connected in sequence. The inlet at the left end of the air-liquid heat exchanger 1 is connected to the output end of the fan 8. The whole system operates under normal pressure, and the fan 8 is used to transport the combustion-supporting air and control the pressure system.
[0023] Furthermore, the flue gas lithium bromide heat exchanger 6 includes a housing 61, a tube body 62, a tube sheet 63, a baffle plate 64, and a tube bundle 65. The housing 61 has a hollow cylindrical structure with an open right end. The tube body 62 has a tubular structure with an end cover 66 provided at its right end. The left end opening of the tube body 62 and the right end opening of the housing 61 are connected by the tube sheet 63. A shunt partition 67 is provided horizontally in the middle of the housing 61. The flue gas lithium bromide heat exchanger lithium bromide solution inlet S7 and the flue gas lithium bromide heat exchanger heat exchanger gas-liquid outlet S8 are respectively provided at the top and bottom of the housing 61. An air inlet and an air outlet are respectively provided at the top left end and the bottom right end of the tube body 62. The tube bundle 65 has a U-shaped structure. A plurality of tube bundle holes 68 for fixing both ends of the tube bundle 65 are respectively provided above and below the outer wall of the tube sheet 63. The baffle plate 64 has a three-quarter circular structure, and a through hole for the tube bundle 65 to pass through is provided on the outer wall of the baffle plate 64. The baffle plate 64 is alternately arranged above and below the inner wall of the tube body 62 along the length direction of the tube body 62, and the baffle plate 64 is in close contact with the inner wall of the tube body 62. During operation, the lithium bromide aqueous solution enters the upper cavity of the housing 61 from the flue gas lithium bromide heat exchanger lithium bromide solution inlet S7, then enters the tube bundle through the upper end of the tube bundle 65, flows along the tube bundle 65, flows to the lower cavity of the housing 61 from the lower end of the tube bundle 65, and flows out through the flue gas lithium bromide heat exchanger heat exchanger gas-liquid outlet S8 after absorbing heat. The flue gas after the first heat exchange treatment enters through the air inlet at the top left end of the tube body 62, and after fully absorbing heat along the S-shaped channel formed by the baffle plate 64 partitioning the inner cavity of the tube body 62, it is discharged from the air outlet at the bottom right end of the tube body 62.
[0024] Furthermore, the spacing between the baffles 64 gradually decreases from the air inlet to the air outlet. Along the length of the tube, as the condensation amount increases, the gas flow rate decreases, the flow velocity reduces, and the heat transfer deteriorates. At this time, the baffle spacing gradually decreases, which can effectively increase the gas flow velocity and enhance the condensation heat transfer.
[0025] Furthermore, a quick tightening mechanism 18 capable of quickly tightening against the tube bundle 65 is provided on the outer wall of the baffle 64. The quick tightening mechanism 18 includes a first limiting ring 181, a second limiting ring 182, a tightening ring 183, an ear plate 184, a locking bolt 185, and a locking nut 186. The axials of the first limiting ring 181, the tightening ring 183, and the second limiting ring 182 are sequentially sleeved on the outside of the tube bundle 65 from one end close to the outer wall of the baffle 64 to the outside. The inner end of the first limiting ring 181 is fixed on the outer wall of the baffle 64. The cross-section of the tightening ring 183 is an isosceles trapezoidal structure with a width gradually increasing from the outside to the inside. The outer end of the first limiting ring 181 and the inner end of the second limiting ring 182 are respectively provided with inclined rings 187 for clamping the outer walls on both sides of the tightening ring 183. The slope of the inclined ring 187 is the same as the slopes of the two side walls of the tightening ring 183. A plurality of the ear plates 184 are spaced on the outer wall of the inclined ring 187. A bolt hole for the locking bolt 185 to pass through is provided axially on the ear plate 184. The locking bolt 185 passes through the bolt hole and is threadedly connected to the locking nut 186. By providing the quick tightening mechanism 18, it is convenient to adjust the spacing between the baffles 64, and after the spacing between the baffles 64 is adjusted, the baffle 64 can be locked to ensure that the baffle 64 does not displace during the working process. Working process of the quick tightening mechanism 18: First, fix the inner end of the first limiting ring 181 on the outer wall of the baffle 64, and then sequentially sleeve the axials of the first limiting ring 181, the tightening ring 183, and the second limiting ring 182 on the outside of the tube bundle 65 from one end close to the outer wall of the baffle 64 to the outside. When the baffle 64 moves along the tube bundle 65 through the through hole thereon to a suitable spacing, the user tightens the locking bolt 185 and the locking nut 186. During the tightening process, the clamping force of the inclined rings 187 at the outer end of the first limiting ring 181 and the inner end of the second limiting ring 182 acts on the two inclined surfaces of the tightening ring 183. When the horizontal clamping force acts on the inclined surface, a partial radial component force will be generated to tightly contact the inner wall of the rubber-made tightening ring 183 with the outer wall of the tube bundle 65, thereby realizing the locking of the baffle 64. When it is necessary to move the baffle 64, loosen the locking bolt 185 and the locking nut 186.
[0026] The above are only embodiments of the present invention, and thus do not limit the patent scope of the present invention. Any equivalent transformation made by using the content of the specification and drawings of the present invention, or any direct or indirect application in related technical fields, shall similarly be included within the patent protection scope of the present invention.
Claims
1. An integrated system for efficient recovery of waste heat from sulfur-containing flue gas and combustion air, characterized in that: It includes a flue gas pretreatment unit and a waste heat deep recovery unit. The flue gas pretreatment unit includes a flue gas-oil heat exchanger (5), an oil pipeline circulation pump (10) and an air-oil heat exchanger (4). An air inlet for untreated flue gas is provided at the left end of the flue gas-oil heat exchanger (5). A flue gas-oil heat exchanger oil outlet (S11) and a flue gas-oil heat exchanger inlet (S12) are respectively provided at both ends of the outer wall of the flue gas-oil heat exchanger (5). An air-oil heat exchanger oil inlet (S9) and an air-oil heat exchanger oil outlet (S10) are respectively provided at both ends of the outer wall of the air-oil heat exchanger (4). The flue gas-oil heat exchanger oil outlet (S11) is communicated with the air-oil heat exchanger oil inlet (S9) through the oil pipeline circulation pump (10). The air-oil heat exchanger oil outlet (S10) is communicated with the flue gas-oil heat exchanger inlet (S12). The air outlet at the right end of the flue gas-oil heat exchanger (5) is connected to the waste heat deep recovery unit.
2. The integrated system for efficient recovery of waste heat from sulfur-containing flue gas and combustion-supporting air according to claim 1, characterized in that: The waste heat deep recovery unit includes a flue gas lithium bromide heat exchanger (6), a first circulation pump (16), a gas-liquid separation device (15), a condensate water tank (11), a condensate water heat exchanger (2), a steam-air heat exchanger (3) and a flue gas temperature regulator (12). The air inlet at the left end of the flue gas lithium bromide heat exchanger (6) is communicated with the air outlet at the right end of the flue gas-oil heat exchanger (5). A flue gas lithium bromide heat exchanger lithium bromide solution inlet (S7) and a flue gas lithium bromide heat exchanger heat exchanger gas-liquid outlet (S8) are respectively provided at both ends of the outer wall of the flue gas lithium bromide heat exchanger (6). The flue gas lithium bromide heat exchanger heat exchanger gas-liquid outlet (S8) is communicated with the gas-liquid separation device (15) through the first circulation pump (16). One side outlet of the gas-liquid separation device (15) is communicated with the flue gas lithium bromide heat exchanger lithium bromide solution inlet (S7) through the flue gas temperature regulator (12). The other side outlet of the gas-liquid separation device (15) is communicated with a steam-air heat exchanger water vapor inlet (S6) on one side of the outer wall of the steam-air heat exchanger (3). A steam-air heat exchanger liquid outlet (S5) on the other side of the outer wall of the steam-air heat exchanger (3) is communicated with one side inlet of the condensate water tank (11). One side outlet of the condensate water tank (11) is communicated with one side inlet of the outer wall of the condensate water heat exchanger (2). The outlet on the other side of the outer wall of the condensate water heat exchanger (2) is communicated with the other side inlet of the condensate water tank (11) through a second circulation pump (17). The other side outlet of the condensate water tank (11) is communicated with the flue gas temperature regulator (12).
3. An integrated system for efficient recovery of waste heat from sulfur-containing flue gas and combustion-supporting air according to claim 2, characterized in that: The condensate water tank (11) is communicated with the flue gas temperature regulator (12) through an electric control valve (14).
4. An integrated system for efficient recovery of waste heat from sulfur-containing flue gas and combustion-supporting air according to claim 3, characterized in that: It further includes a desulfurization synergistic unit, and the desulfurization synergistic unit includes an air-liquid heat exchanger (1), a desulfurization tower (7), a double-liquid heat exchanger (9) and a third circulation pump (13). The air outlet at the right end of the flue gas lithium bromide heat exchanger (6) is communicated with the air inlet below the left side wall of the desulfurization tower (7), and an air outlet is provided below the right side wall of the desulfurization tower (7); the double-liquid heat exchanger (9) is arranged at the bottom of the inner cavity of the desulfurization tower (7), the double-liquid heat exchanger outlet (S4) of the double-liquid heat exchanger (9) is communicated with the air-liquid heat exchanger liquid inlet (S1) on one side of the outer wall of the air-liquid heat exchanger (1), and the air-liquid heat exchanger liquid outlet (S2) on the other side of the outer wall of the air-liquid heat exchanger (1) is communicated with the double-liquid heat exchanger inlet (S3) of the double-liquid heat exchanger (9) through the third circulation pump (13).
5. An integrated system for efficient recovery of waste heat from sulfur-containing flue gas and combustion air according to claim 4, characterized in that: The air-liquid heat exchanger (1), the condensate heat exchanger (2), the steam-air heat exchanger (3) and the air-oil heat exchanger (4) are communicated in sequence, and the inlet at the left end of the air-liquid heat exchanger (1) is communicated with the output end of the fan (8).
6. The integrated system for efficient recovery of waste heat from sulfur-containing flue gas and combustion-supporting air according to claim 2, wherein: The flue gas lithium bromide heat exchanger (6) includes a shell (61), a tube body (62), a tube sheet (63), a baffle plate (64) and a tube bundle (65). The shell (61) has a hollow cylindrical structure with an open right end. The tube body (62) has a tubular structure, and a end cover (66) is provided at its right end. The left end opening of the tube body (62) and the right end opening of the shell (61) are connected by the tube sheet (63). A shunt partition plate (67) is provided in the middle of the shell (61) along the horizontal direction. The lithium bromide solution inlet (S7) of the flue gas lithium bromide heat exchanger and the heat exchanger gas-liquid outlet (S8) of the flue gas lithium bromide heat exchanger are respectively provided at the top and bottom of the shell (61). An air inlet and an air outlet are respectively provided at the left end of the top and the right end of the bottom of the tube body (62); the tube bundle (65) has a U-shaped structure. Tube bundle holes (68) for fixing both ends of the tube bundle (65) are respectively provided above and below the outer wall of the tube sheet (63). The baffle plate (64) has a three-quarter circular structure, and a through hole for the tube bundle (65) to pass through is provided on the outer wall of the baffle plate (64). The baffle plates (64) are alternately arranged above and below the inner wall of the tube body (62) along the length direction of the tube body (62), and the baffle plates (64) are in close contact with the inner wall of the tube body (62).
7. An integrated system for efficient recovery of waste heat from sulfur-containing flue gas and combustion-supporting air according to claim 6, characterized in that: The distance between the baffle plates (64) gradually decreases from the air inlet to the air outlet.
8. An integrated system for efficient recovery of waste heat from sulfur-containing flue gas and combustion air according to claim 7, characterized in that: A quick-tightening mechanism (18) capable of quickly pressing against the tube bundle (65) is provided on the outer wall of the baffle plate (64). The quick-tightening mechanism (18) includes a first limiting ring (181), a second limiting ring (182), a pressing ring (183), an ear plate (184), a locking bolt (185) and a locking nut (186). The axials of the first limiting ring (181), the pressing ring (183) and the second limiting ring (182) are sequentially sleeved on the outside of the tube bundle (65) from one end close to the outer wall of the baffle plate (64) to the outside. The inner end of the first limiting ring (181) is fixed on the outer wall of the baffle plate (64). The cross-section of the pressing ring (183) is an isosceles trapezoid structure with a width gradually increasing from the outside to the inside. Oblique rings (187) for clamping the outer walls on both sides of the pressing ring (183) are respectively provided at the outer end of the first limiting ring (181) and the inner end of the second limiting ring (182). The slope of the oblique ring (187) is the same as the slopes of the two side walls of the pressing ring (183). A plurality of the ear plates (184) are spaced on the outer wall of the oblique ring (187). A bolt hole for the locking bolt (185) to pass through is provided axially on the ear plate (184). The locking bolt (185) passes through the bolt hole and is threadedly connected with the locking nut (186).