Air preheater for preparing sulfuric acid by wet method

Abstract

The utility model relates to an air preheater for preparing sulfuric acid by a wet method, which is characterized in that an inner cavity of a heating cylinder is divided into an exhaust cavity, a heating cavity and an air inlet cavity, two partition plates are jointly and fixedly connected with a plurality of guide pipes which are uniformly distributed around the axis of the partition plates, and the inlet end of the air inlet cavity is fixedly communicated with an air supply device. The outlet end of the exhaust cavity is fixedly communicated with an exhaust device; a heat exchanger is arranged on one side of the heating cylinder, the inlet end of the heat exchanger is fixedly communicated with the outlet end of a left smoke inlet pipe, the outlet end of the heat exchanger is fixedly communicated with the inlet end of a right smoke inlet pipe, the outlet end of the right smoke inlet pipe is fixedly communicated with the inlet end of a heating cavity, and the outlet end of the heating cavity is fixedly communicated with the inlet end of an exhaust fan. The outlet end of the exhaust fan fixedly communicates with a smoke exhaust pipe, the two vertical rods are vertically and slidably connected with blocking discs, through holes corresponding to the guide pipes one to one are formed in the blocking discs, and a driving device used for driving the blocking discs is arranged on the heating cylinder.

Description

Technical Field

[0001] The utility model relates to the technical field of air heating devices, in particular to an air preheater for wet-process sulfuric acid production. Background Art

[0002] Wet sulfuric acid production is a common production process. The WSA condenser is the core heat exchange equipment for concentrated sulfuric acid generation in the wet acid sulfur recovery (WSA) device. The internal heat exchange tube is made of corrosion-resistant high-boron glass. The process of sulfuric acid generation is an exothermic process. The chemical reaction takes place inside the heat exchange tube, and the outside of the heat exchange tube is air for cooling. In order to reduce the risk of rupture of the heat exchange tube due to the large temperature difference between the inside and outside, in order to reduce the temperature difference, the cooling air used for cooling needs to be preheated before entering the heat exchanger. At present, steam heating is often used for preheating cooling air. The steam used is 0.5MPa saturated steam. Due to the low quality of the saturated steam, cavitation is found during the operation of the equipment. There are many scouring and leakage at the elbow of the equipment, which is extremely unfavorable to the stable operation of the WSA condenser. The direct discharge of the steam boiler exhaust gas causes a large amount of heat loss. Therefore, this application proposes an air preheater for wet sulfuric acid production to solve the above problems. Utility Model Content

[0003] In view of the above situation, in order to overcome the defects of the prior art, the utility model provides an air preheater for wet sulfuric acid production, and the technical solution to the problem is to include a heating cylinder, characterized in that the inner wall of the heating cylinder is fixedly connected with two partitions arranged at intervals along the vertical direction, the two partitions divide the inner cavity of the heating cylinder into three parts: an exhaust cavity, a heating cavity and an air intake cavity, the two partitions are commonly fixedly connected with a plurality of conduits uniformly distributed around the axis thereof, the inlet end of each conduit extends downward into the air intake cavity, the outlet end of each conduit extends upward into the exhaust cavity, the inlet end of the air intake cavity is fixedly connected with an air supply device, and the outlet end of the exhaust cavity is fixedly connected with an exhaust device;

[0004] A heat exchanger is arranged on one side of the heating cylinder, the inlet end of the heat exchanger is fixedly connected with the outlet end of the left smoke inlet pipe, the outlet end of the heat exchanger is fixedly connected with the inlet end of the right smoke inlet pipe, the outlet end of the right smoke inlet pipe is fixedly connected with the inlet end of the heating chamber, the outlet end of the heating chamber is fixedly connected with the inlet end of the exhaust fan, the outlet end of the exhaust fan is fixedly connected with the smoke exhaust pipe, the opposite ends of the two partitions are fixedly connected with two vertical rods symmetrically arranged about their axes, the two vertical rods are vertically slidably connected with a baffle plate coaxially arranged with the heating chamber, the baffle plate is provided with a plurality of through holes corresponding to the conduits one by one, the inner walls of the through holes are in sliding contact with the outer wall of the conduit, and the heating cylinder is provided with a driving device for driving the baffle plate to slide along the vertical rod.

[0005] Preferably, the driving device includes a reciprocating screw rotatably connected to the opposite ends of the two partitions, the baffle plate is fixedly connected with two sliding blocks corresponding to the vertical rods one by one and vertically slidably connected, the baffle plate is fixedly connected with a screw sleeve threadedly connected to the reciprocating screw, the bottom surface of the air intake chamber is rotatably connected with a driving shaft, the driving shaft is coaxially fixedly connected with a driving gear, the lower end of the reciprocating screw is fixedly connected with a driven gear meshing with the driving gear, and the bottom of the air intake chamber is fixedly connected with a motor for driving the driving shaft.

[0006] Preferably, the air supply device comprises a cold air blower located at one side of the heating cylinder, and the outlet end of the cold air blower is fixedly connected to the inlet end of the air inlet cavity.

[0007] Preferably, the exhaust device comprises an inlet end of a hot air blower fixedly connected to an outlet end of the exhaust chamber, and the outlet end of the hot air blower is fixedly connected to an exhaust pipe.

[0008] Preferably, a cleaning window is fixedly connected to the bottom of the heating chamber, and a sealing cover is detachably connected to the opening end of the cleaning window.

[0009] The beneficial effects of the utility model are:

[0010] 1. When the utility model is in use, the exhaust gas of the steam boiler is sent to the heat exchanger through the left smoke inlet pipe for heat exchange and cooling. The boiler exhaust gas after heat exchange and cooling is sent to the heating chamber of the heating cylinder through the right smoke inlet pipe, which can heat and increase the temperature of the conduit and the gas in the conduit. The air supply device sends cooling air into the conduit. When the cooling air flows in the conduit, it is heated by the boiler exhaust gas in the heating chamber, that is, the preheating of the cooling air is completed. The preheated cooling air is sent to the outside of the heat exchange tube in the WSA condenser through the hot air blower for cooling. The present application has a simple structure, is easy to use, and has strong practicality. It solves the adverse effects of traditional steam preheating and also utilizes the preheating of the boiler exhaust gas.

[0011] 2. The driving device provided can drive the baffle to move vertically back and forth. During the reciprocating movement of the baffle, the inner wall of the through hole and the outer edge of the conduit rub against each other, thereby removing the soot attached to the conduit and preventing the soot from attaching to the conduit and affecting the preheating of the cooling air. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a full cutaway front view of the utility model.

[0013] Figure 2 This is a partial three-dimensional cross-sectional view of the utility model from the first viewing angle.

[0014] Figure 3 It is an enlarged view of area A in the partial stereoscopic cross-sectional view from the first viewing angle of the utility model.

[0015] Figure 4This is a partial stereoscopic view from the second viewing angle of the utility model.

[0016] Figure 5 This is a partial stereoscopic view of the utility model from the third viewing angle.

[0017] Figure 6 This is a stereoscopic view from the fourth viewing angle of the present invention.

[0018] Reference numerals

[0019] 1. Heating cylinder, 2. Partition, 3. Exhaust chamber, 4. Heating chamber, 5. Inlet chamber, 6. Conduit, 7. Heat exchanger, 8. Left smoke inlet pipe, 9. Right smoke inlet pipe, 10. Exhaust fan, 11. Exhaust pipe, 12. Vertical rod, 13. Baffle plate, 14. Through hole, 15. Reciprocating screw, 16. Slider, 17. Screw sleeve, 18. Driving shaft, 19. Driving gear, 20. Driven gear, 21. Motor, 22. Cooling fan, 23. Hot air blower, 24. Exhaust pipe, 25. Cleaning window, 26. Sealing cover. DETAILED DESCRIPTION

[0020] The following is combined with Figure 1-6 The specific implementation methods of the utility model are further described in detail.

[0021] Embodiment 1, the technical solution is that when the utility model is in use, the exhaust gas of the steam boiler is sent to the heat exchanger 7 through the left smoke inlet pipe 8 for heat exchange and cooling, and the boiler exhaust gas after heat exchange and cooling is sent to the heating chamber 4 of the heating tube 1 through the right smoke inlet pipe 9, which can heat and increase the temperature of the conduit 6 and the gas in the conduit 6, and the air supply device sends the cooling air into the conduit 6. When the cooling air flows in the conduit 6, it is heated by the boiler exhaust gas in the heating chamber 4, that is, the preheating of the cooling air is completed, and the preheated cooling air is sent to the outside of the heat exchange tube in the WSA condenser through the hot air blower 23 for cooling. The present application has a simple structure, is easy to use, and has strong practicality. It solves the adverse effects of traditional steam preheating and also utilizes the preheating of the boiler exhaust gas.

[0022] When the present application is in use, the exhaust gas of the steam boiler inevitably contains soot which is easy to adhere to the outer wall of the conduit 6, thereby affecting the preheating efficiency of the cooling air. To avoid this phenomenon, a driving device is provided to drive the baffle plate 13 to move back and forth vertically. During the reciprocating movement of the baffle plate 13, the inner wall of the through hole 14 and the outer edge of the conduit 6 rub against each other, thereby removing the soot attached to the conduit 6, thereby preventing the soot from adhering to the conduit 6 and affecting the preheating of the cooling air.

[0023] Embodiment 2. On the basis of embodiment 1, the heating cylinder 1 of the present application is divided into an exhaust chamber 3, a heating chamber 4 and an air intake chamber 5 from top to bottom under the action of two partitions 2. The conduit 6 is located in the heating chamber 4 except for the two ends, so that the cooling air in the conduit 6 and the steam boiler exhaust gas in the heating chamber 4 can exchange heat and heat up to complete preheating. The baffle 13 in the heating chamber 4 can also block the steam boiler exhaust gas, so that the steam boiler exhaust gas can stay in the heating cylinder 1 for a longer time, which is convenient for preheating and heating the cooling air in the conduit 6. Furthermore, in order to facilitate the flow renewal of the filtered exhaust gas in the heating cylinder 1, an exhaust fan 10 is arranged on the top of the heating chamber 4 to guide the steam filtered exhaust gas in the heating chamber 4 to flow upward and be discharged from the smoke exhaust pipe 11.

[0024] When the present application is in use, the cold air blower 22 of the air supply device delivers the cooling air into the duct 6 through the air inlet chamber 5. The cooling air entering the duct 6 is preheated and heated in the heating chamber 4. Thereafter, the cooling air is delivered to the exhaust duct 24 under the action of the hot air blower 23 of the exhaust device. The exhaust duct is connected to the WSA condenser (the specific connection method can adopt the existing technology) so as to deliver the preheated cooling air to the outside of the heat exchange tube in the WSA condenser for cooling.

[0025] Embodiment 3, on the basis of embodiment 2, since the exhaust gas of the steam boiler often contains smoke and dust, which will adhere to the conduit 6 and affect preheating, it is necessary to start the driving device regularly for cleaning, specifically: starting the motor 21 drives the driving shaft 18 to rotate, and the driving shaft 18 will drive the reciprocating screw 15 to rotate through the cooperation of the driving gear 19 and the driven gear 20, and the rotation of the reciprocating screw 15 will drive the baffle 13 through the screw sleeve 17, and the baffle 13 is restricted by the vertical sliding connection between the slider 16 and the vertical rod 12, so under the drive of the reciprocating screw 15, the baffle 13 will move vertically back and forth along the vertical rod 12, and during the reciprocating movement of the baffle 13, the inner wall of the through hole 14 and the outer edge of the conduit 6 rub against each other, thereby removing the smoke attached to the conduit 6, and preventing the smoke from adhering to the conduit 6 and affecting the preheating of the cooling air. The sealing cover 26 is plug-in-plug connected to the cleaning window 25 , and the smoke and dust cleaned by the movement of the baffle plate 13 falls on the partition plate 2 below. The sealing cover 26 can be opened to clean out the accumulated smoke and dust from the cleaning window 25 .

Claims

1. An air preheater for wet sulfuric acid production, comprising a heating cylinder (1), characterized in that: The inner wall of the heating cylinder (1) is fixedly connected to two partitions (2) arranged at intervals along the vertical direction, the two partitions (2) divide the inner cavity of the heating cylinder (1) into three parts: an exhaust cavity (3), a heating cavity (4) and an air intake cavity (5), the two partitions (2) are commonly fixedly connected to a plurality of ducts (6) uniformly distributed around the axis thereof, the inlet end of each duct (6) extends downward into the air intake cavity (5), the outlet end of each duct (6) extends upward into the exhaust cavity (3), the inlet end of the air intake cavity (5) is fixedly connected to an air supply device, and the outlet end of the exhaust cavity (3) is fixedly connected to an exhaust device; A heat exchanger (7) is arranged on one side of the heating cylinder (1); the inlet end of the heat exchanger (7) is fixedly connected to the outlet end of the left smoke inlet pipe (8); the outlet end of the heat exchanger (7) is fixedly connected to the inlet end of the right smoke inlet pipe (9); the outlet end of the right smoke inlet pipe (9) is fixedly connected to the inlet end of the heating chamber (4); the outlet end of the heating chamber (4) is fixedly connected to the inlet end of the exhaust fan (10); the outlet end of the exhaust fan (10) is fixedly connected to the smoke exhaust pipe (11); Two vertical rods (12) symmetrically arranged about their axes are fixedly connected to the opposite ends of the two partitions (2); the two vertical rods (12) are vertically slidably connected to a baffle (13) coaxially arranged with the heating chamber (4); the baffle (13) is provided with a plurality of through holes (14) corresponding one to one with the conduits (6); the inner walls of the through holes (14) are in sliding contact with the outer wall of the conduit (6); and a driving device for driving the baffle (13) to slide along the vertical rods (12) is arranged on the heating cylinder (1).

2. The air preheater for wet sulfuric acid production according to claim 1, characterized in that: The driving device comprises a reciprocating screw (15) rotatably connected to opposite ends of the two partitions (2); the baffle plate (13) is fixedly connected to two sliding blocks (16) corresponding to the vertical rods (12) one by one and vertically slidably connected; the baffle plate (13) is fixedly connected to a screw sleeve (17) threadedly connected to the reciprocating screw (15); the inner bottom surface of the air inlet chamber (5) is rotatably connected to a driving shaft (18); the driving shaft (18) is coaxially fixedly connected to a driving gear (19); the lower end of the reciprocating screw (15) is fixedly connected to a driven gear (20) meshing with the driving gear (19); and the bottom of the air inlet chamber (5) is fixedly connected to a motor (21) for driving the driving shaft (18).

3. The air preheater for wet sulfuric acid production according to claim 1, characterized in that: The air supply device comprises a cold air fan (22) located on one side of the heating cylinder (1), and the outlet end of the cold air fan (22) is fixedly connected to the inlet end of the air inlet cavity (5).

4. The air preheater for wet sulfuric acid production according to claim 1, characterized in that: The exhaust device comprises an inlet end of a hot air blower (23) fixedly connected to an outlet end of the exhaust chamber (3); the outlet end of the hot air blower (23) is fixedly connected to an exhaust pipe (24).

5. The air preheater for wet sulfuric acid production according to claim 1, characterized in that: A cleaning window (25) is fixedly connected to the bottom of the heating chamber (4), and a sealing cover (26) is detachably connected to the opening end of the cleaning window (25).

Images