Method for recovering heat energy of low-grade limestone dephosphorization and desulfurization calcination flue gas

Abstract

The invention discloses a low-grade limestone dephosphorization and desulfurization calcination flue gas heat energy recovery method, which comprises the following steps that A, a water body is injected into a water tank from a water inlet in advance, low-grade limestone dephosphorization and desulfurization calcination flue gas is sucked into a cover body from a first air inlet pipe, and in the process, a spoiler is blown; heat of the low-grade limestone dephosphorization and desulfurization calcination flue gas can be transferred into a water body in the water tank through the heat exchange pipe and the heat exchanger, and after the low-grade limestone dephosphorization and desulfurization calcination flue gas enters the cover body, the spoiler can be blown to rotate; the spoiler can drive the stirring shaft at the upper end to rotate through the single-sided tooth synchronous belt while rotating, and the stirring shaft at the upper end can drive the stirring shaft at the lower end to rotate through the single-sided tooth synchronous belt while rotating, so that a water body in the water tank is stirred by stirring blades; therefore, the heat energy recovery effect of the low-grade limestone dephosphorization and desulfurization calcination flue gas is further improved.

Description

Technical Field

[0001] The invention relates to the technical field of flue gas heat energy recovery, and in particular to a method for recovering heat energy from flue gas produced by dephosphorization, desulfurization and calcination of low-grade limestone. Background Art

[0002] Lime or limestone desulfurization refers to the process of using lime or limestone slurry to absorb sulfur dioxide in flue gas in an absorption tower to obtain a mixture of calcium sulfite and calcium sulfate, which is then sent to an oxidation tower and oxidized by air. The resulting calcium sulfate slurry is centrifugally filtered and washed to obtain finished calcium sulfate (gypsum). In order to achieve heat energy recovery, the low-grade limestone dephosphorization, desulfurization and calcination flue gas needs to be transported to a water tank. However, the existing heat energy recovery methods all directly transport hot air to a water tank, resulting in a low overall heat energy recovery rate. For this reason, we propose a heat energy recovery method for low-grade limestone dephosphorization, desulfurization and calcination flue gas. Summary of the invention

[0003] The object of the present invention is to provide a method for recovering heat energy from flue gas calcined with low-grade limestone for dephosphorization and desulfurization, so as to solve the problems raised in the above-mentioned background technology.

[0004] To achieve the above object, the present invention provides the following technical solution: a method for recovering heat energy from flue gas during calcination of low-grade limestone for dephosphorization and desulfurization, comprising the following steps: A. Inject water into the water tank from the water inlet in advance, and the low-grade limestone dephosphorization, desulfurization and calcination flue gas is sucked into the cover from the first air inlet pipe. During this process, the spoiler will be blown, and then the low-grade limestone dephosphorization, desulfurization and calcination flue gas enters the diversion box from the first air outlet pipe and enters the diversion trough; B. A part of the low-grade limestone dephosphorization, desulfurization and calcination flue gas will enter the heat exchange tube, and another part of the low-grade limestone dephosphorization, desulfurization and calcination flue gas will enter the heat exchanger from the second air inlet pipe and finally be discharged from the second air outlet pipe; C. The heat exchange tube and the heat exchanger exchange heat with the water in the water tank, and the spoiler drives the stirring shaft at the upper end to rotate through the single-sided toothed synchronous belt while rotating, and the stirring shaft at the upper end drives the stirring shaft at the lower end to rotate through the single-sided toothed synchronous belt while rotating, so that the stirring blades stir the water in the water tank, so as to further improve the heat recovery effect of the low-grade limestone dephosphorization and desulfurization calcination flue gas; D. Control the extension of the hydraulic rod to make the travel wheels contact the ground, making it easier for people to move the device.

[0005] Preferably, the upper and lower ends of the water tank inner cavity are movably connected with a stirring shaft, the outer surface of the stirring shaft is fixedly connected with a stirring blade, the upper and lower stirring shafts are connected by a single-sided toothed synchronous belt transmission, the middle end of the left side of the water tank is fixedly connected with a cover body, the right end of the inner cavity of the cover body is fixedly connected with a partition, the left side of the water tank and located on the inner side of the cover body is movably connected with a spoiler, and the right end of the spoiler is connected to the stirring shaft at the upper end through a single-sided toothed synchronous belt.

[0006] Preferably, the inner cavity of the water tank is fixedly connected to a plurality of equidistantly distributed heat exchange tubes, the left and right sides of the inner cavity of the water tank are fixedly connected to brackets, the inner side of the bracket is fixedly connected to a heat exchanger, and the right end of the back side of the heat exchanger is connected to a second air outlet pipe.

[0007] Preferably, the left end of the back side of the cover body is connected to a first air inlet pipe, the left end of the front side of the cover body is connected to the middle end of the front side of the diversion box through a first air outlet pipe, the front side of the water tank is fixedly connected to the diversion box, the inner cavity of the diversion box is provided with a diversion groove, the front side of the heat exchange tube is connected to the back side of the diversion groove, and the left end of the back side of the diversion groove is connected to the left end of the front side of the heat exchanger through a second air inlet pipe.

[0008] Preferably, a water inlet is provided at the right end of the top of the water tank, a water outlet is provided at the bottom of the left side of the water tank, the ends of the water outlet and the water inlet are threadedly connected with sealing covers, support legs are fixedly connected around the bottom of the water tank, a reserved groove is provided at the bottom of the support leg, a hydraulic rod is fixedly connected to the top of the inner cavity of the reserved groove, and the telescopic end of the hydraulic rod is movably connected to a walking wheel.

[0009] Compared with the prior art, the present invention has the following beneficial effects: The present invention can transfer the heat of the low-grade limestone dephosphorization, desulfurization and calcination flue gas itself to the water in the water tank through the heat exchange tube and the heat exchanger, and after the low-grade limestone dephosphorization, desulfurization and calcination flue gas enters the cover body, it will blow the spoiler to rotate, and the spoiler will drive the upper stirring shaft to rotate through the single-sided toothed synchronous belt while rotating, and the upper stirring shaft will drive the lower stirring shaft to rotate through the single-sided toothed synchronous belt while rotating, so that the stirring blades stir the water in the water tank, so as to further improve the heat energy recovery effect of the low-grade limestone dephosphorization, desulfurization and calcination flue gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention in the first viewing angle state; Figure 2 It is a schematic diagram of the three-dimensional structure of the present invention in a second viewing angle state; Figure 3 It is a schematic diagram of the cross-sectional structure of the present invention; Figure 4 It is a schematic diagram of the cross-sectional structure of the support leg of the present invention.

[0011] In the figure: water tank 1, cover body 2, water outlet 3, diverter box 4, first air outlet pipe 5, water inlet 6, second air outlet pipe 7, first air inlet pipe 8, stirring blade 9, support leg 10, heat exchange pipe 11, partition 12, spoiler 13, stirring shaft 14, bracket 15, second air inlet pipe 16, diverter slot 17, heat exchanger 18, walking wheel 19, reserved slot 20, hydraulic rod 21. DETAILED DESCRIPTION

[0012] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0013] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0014] See also Figure 1-Figure 4 A method for recovering heat energy from flue gas calcined with low-grade limestone for dephosphorization and desulfurization comprises the following steps: A. Inject water into the water tank 1 from the water inlet 6 in advance, and the low-grade limestone dephosphorization, desulfurization and calcination flue gas is sucked into the cover body 2 from the first air inlet pipe 8. During this process, the spoiler 13 will be blown, and then the low-grade limestone dephosphorization, desulfurization and calcination flue gas enters the diversion box 4 from the first air outlet pipe 5, and enters the diversion trough 17; B. A part of the low-grade limestone dephosphorization and desulfurization calcination flue gas will enter the heat exchange tube 11, and another part of the low-grade limestone dephosphorization and desulfurization calcination flue gas will enter the heat exchanger 18 from the second air inlet pipe 16, and finally be discharged from the second air outlet pipe 7; C. The heat exchange tube 11 and the heat exchanger 18 exchange heat with the water in the water tank 1, and the spoiler 13 drives the stirring shaft 14 at the upper end to rotate through the single-sided toothed synchronous belt while rotating, and the stirring shaft 14 at the upper end drives the stirring shaft 14 at the lower end to rotate through the single-sided toothed synchronous belt while rotating, so that the stirring blade 9 stirs the water in the water tank 1, so as to further improve the heat recovery effect of the low-grade limestone dephosphorization and desulfurization calcination flue gas; D. Control the hydraulic rod 21 to extend so that the travel wheel 19 contacts the ground, thereby making it convenient for people to move the device.

[0015] The upper and lower ends of the inner cavity of the water tank 1 are movably connected with a stirring shaft 14, the outer surface of the stirring shaft 14 is fixedly connected with a stirring blade 9, the upper and lower stirring shafts 14 are connected by a single-sided toothed synchronous belt transmission, the middle end of the left side of the water tank 1 is fixedly connected with a cover body 2, the right end of the inner cavity of the cover body 2 is fixedly connected with a partition 12, the left side of the water tank 1 and located on the inner side of the cover body 2 is movably connected with a spoiler 13, and the right end of the spoiler 13 is connected to the stirring shaft 14 at the upper end by a single-sided toothed synchronous belt.

[0016] The inner cavity of the water tank 1 is fixedly connected with a plurality of equidistantly distributed heat exchange tubes 11, the left and right sides of the inner cavity of the water tank 1 are fixedly connected with brackets 15, the inner side of the brackets 15 is fixedly connected with a heat exchanger 18, and the right end of the back side of the heat exchanger 18 is connected with a second air outlet pipe 7.

[0017] The left end of the back side of the cover body 2 is connected to the first air inlet pipe 8, the left end of the front side of the cover body 2 is connected to the middle end of the front side of the diverter box 4 through the first air outlet pipe 5, the front side of the water tank 1 is fixedly connected to the diverter box 4, the inner cavity of the diverter box 4 is provided with a diverter groove 17, the front side of the heat exchange tube 11 is connected to the back side of the diverter groove 17, and the left end of the back side of the diverter groove 17 is connected to the left end of the front side of the heat exchanger 18 through the second air inlet pipe 16.

[0018] A water inlet 6 is provided at the right end of the top of the water tank 1, a water outlet 3 is provided at the bottom of the left side of the water tank 1, and sealing covers are threadedly connected to the ends of the water outlet 3 and the water inlet 6. Support legs 10 are fixedly connected around the bottom of the water tank 1, and a reserved groove 20 is provided at the bottom of the support leg 10. A hydraulic rod 21 is fixedly connected to the top of the inner cavity of the reserved groove 20, and the telescopic end of the hydraulic rod 21 is movably connected to a walking wheel 19.

[0019] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for recovering heat energy from flue gas from calcination of low-grade limestone for dephosphorization and desulfurization, characterized in that: The following steps are involved: A. Inject water into the water tank (1) from the water inlet (6) in advance, and the low-grade limestone dephosphorization, desulfurization and calcination flue gas is sucked into the cover body (2) from the first air inlet pipe (8). During this process, the spoiler (13) is blown, and then the low-grade limestone dephosphorization, desulfurization and calcination flue gas enters the diversion box (4) from the first air outlet pipe (5), and enters the diversion trough (17); B. A portion of the low-grade limestone dephosphorization, desulfurization and calcination flue gas enters the heat exchange tube (11), and another portion of the low-grade limestone dephosphorization, desulfurization and calcination flue gas enters the heat exchanger (18) from the second air inlet pipe (16) and is finally discharged from the second air outlet pipe (7); C. The heat exchange tube (11) and the heat exchanger (18) exchange heat with the water in the water tank (1), and the spoiler (13) drives the stirring shaft (14) at the upper end to rotate through the single-sided toothed synchronous belt while rotating, and the stirring shaft (14) at the upper end drives the stirring shaft (14) at the lower end to rotate through the single-sided toothed synchronous belt while rotating, so that the stirring blade (9) stirs the water in the water tank (1), thereby further improving the heat recovery effect of the low-grade limestone dephosphorization and desulfurization calcination flue gas; D. Control the hydraulic rod (21) to extend so that the travel wheel (19) contacts the ground, thereby making it easier for people to move the device.

2. The method for recovering heat energy from flue gas from calcination of low-grade limestone for dephosphorization and desulfurization according to claim 1, characterized in that: The upper and lower ends of the inner cavity of the water tank (1) are movably connected to a stirring shaft (14), the outer surface of the stirring shaft (14) is fixedly connected to a stirring blade (9), the upper and lower stirring shafts (14) are connected by a single-sided toothed synchronous belt transmission, the middle end of the left side of the water tank (1) is fixedly connected to a cover body (2), the right end of the inner cavity of the cover body (2) is fixedly connected to a partition plate (12), the left side of the water tank (1) and located inside the cover body (2) is movably connected to a spoiler (13), and the right end of the spoiler (13) is connected to the stirring shaft (14) at the upper end by a single-sided toothed synchronous belt.

3. The method for recovering heat energy from flue gas from calcination of low-grade limestone for dephosphorization and desulfurization according to claim 1, characterized in that: The inner cavity of the water tank (1) is fixedly connected to a plurality of equidistantly distributed heat exchange tubes (11), the left and right sides of the inner cavity of the water tank (1) are fixedly connected to brackets (15), the inner side of the bracket (15) is fixedly connected to a heat exchanger (18), and the right end of the back side of the heat exchanger (18) is connected to a second air outlet pipe (7).

4. The method for recovering heat energy from flue gas from calcination of low-grade limestone for dephosphorization and desulfurization according to claim 3, characterized in that: The left end of the back side of the cover body (2) is connected to a first air inlet pipe (8), the left end of the front side of the cover body (2) is connected to the middle end of the front side of the diverter box (4) through a first air outlet pipe (5), the front side of the water tank (1) is fixedly connected to the diverter box (4), the inner cavity of the diverter box (4) is provided with a diverter groove (17), the front side of the heat exchange tube (11) is connected to the back side of the diverter groove (17), and the left end of the back side of the diverter groove (17) is connected to the left end of the front side of the heat exchanger (18) through a second air inlet pipe (16).

5. The method for recovering heat energy from flue gas from calcination of low-grade limestone for dephosphorization and desulfurization according to claim 1, characterized in that: The water tank (1) has a water inlet (6) at the right end of the top, a water outlet (3) at the bottom of the left side of the water tank (1), the ends of the water outlet (3) and the water inlet (6) are threadedly connected to sealing covers, the bottom of the water tank (1) is fixedly connected to support legs (10) on all sides, a reserved groove (20) is formed at the bottom of the support leg (10), a hydraulic rod (21) is fixedly connected to the top of the inner cavity of the reserved groove (20), and the telescopic end of the hydraulic rod (21) is movably connected to a walking wheel (19).

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