Energy-saving oxidation device for ammonia desulfurization of boiler flue gas

Abstract

The utility model relates to an energy-saving oxidation device for ammonia desulfurization of boiler flue gas. Comprising a desulfurization tower and a circulating tank which is matched with the desulfurization tower to realize circulation and desulfurization, and an air oxidation pipeline is respectively connected with the desulfurization tower and the circulating tank through an energy-saving fan unit and a non-return anti-blocking unit; the energy-saving fan unit at least comprises a magnetic suspension fan; a traditional Roots blower is replaced by the magnetic suspension blower to achieve the purpose of saving energy and reducing consumption, and meanwhile, the non-return anti-blocking unit is arranged to prevent a solution in equipment such as a desulfurizing tower from entering a pipeline and the energy-saving blower unit, so that the purposes of stable operation of the system and prolonging of the service life of the magnetic suspension blower are achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of boiler flue gas ammonia desulfurization, in particular to an energy-saving oxidation device for boiler flue gas ammonia desulfurization. Background Art

[0002] In the prior art, the boiler flue gas desulfurization device adopts ammonia desulfurization to remove sulfur dioxide in the flue gas and achieve standard emission. The removal principle is that ammonia water reacts with sulfur dioxide in the boiler flue gas to generate ammonium sulfite and ammonium bisulfite, which are oxidized with oxygen in the air to obtain ammonium sulfate, which is sold as a product; and the air used in the oxidation process is blown by a Roots blower, which cannot adjust the frequency according to the oxygen demand, resulting in high power consumption. At the same time, there is a defect that the solution in the desulfurization tower and other equipment enters the pipeline to cause blockage, or enters the Roots blower to cause damage to the device. Utility Model Content

[0003] The utility model aims to provide an energy-saving oxidation device for boiler flue gas ammonia desulfurization to overcome the defects in the prior art.

[0004] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0005] An energy-saving oxidation device for ammonia desulfurization of boiler flue gas comprises a desulfurization tower and a circulation tank that cooperates with the desulfurization tower to achieve circulation and desulfurization. An air oxidation pipeline is connected to the desulfurization tower and the circulation tank respectively through an energy-saving fan unit and a non-return and anti-blocking unit; the energy-saving fan unit comprises at least one magnetic suspension fan.

[0006] The beneficial effects of the utility model are as follows: the desulfurization tower described in the utility model is connected to the circulation tank, and the desulfurization liquid inside the desulfurization tower circulates between the desulfurization tower and the circulation tank to achieve desulfurization of the flue gas. During the oxidation process, the air oxidation pipeline provides air to the desulfurization tower and the circulation tank through the energy-saving fan unit to achieve oxidation; in the above process, the utility model is provided with an energy-saving fan unit with a magnetic levitation fan, which can adjust the frequency according to the amount of air required in the circulation tank and the desulfurization tower to achieve energy saving and consumption reduction. The magnetic levitation fan utilizes high-speed permanent magnet motors, high-efficiency fluid mechanical systems, and magnetic levitation bearings and other technologies to achieve high-efficiency energy saving and intelligent control; further, a check and anti-blocking unit is provided in the utility model, so as to prevent the solution in the desulfurization tower and other equipment from entering the pipeline and the energy-saving fan unit, thereby achieving stable operation of the system and increasing the service life of the magnetic levitation fan.

[0007] Preferably, the energy-saving blower unit comprises three blowers arranged in parallel, one of which is a magnetic levitation blower and two of which are Roots blowers; the air oxidation ducts are respectively connected to the above three blowers, and a first control valve is respectively provided between the outlet ends of the three blowers and the check and anti-blocking units.

[0008] Preferably, a vent pipe with an automatic vent valve is provided at the upper portion of the magnetic levitation fan, and a cooling air exhaust pipe for cooling the magnetic levitation fan is provided at the lower portion of the magnetic levitation fan.

[0009] Preferably, the non-return and anti-blocking unit includes a first non-return valve arranged at the outlet end of the energy-saving fan unit, and a second non-return valve arranged on the air intake pipe in front of the desulfurization tower and the circulation tank, and a temperature sensor, a pressure sensor and a first emergency shut-off valve are arranged in sequence between the first non-return valve and the second non-return valve.

[0010] A bellows compensator is provided between the first check valve and the temperature sensor.

[0011] Preferably, a first tee is provided between the first emergency shut-off valve and the second check valve, a pipeline liquid discharge pipe with a second emergency shut-off valve is provided at the third end of the first tee, and the end of the pipeline liquid discharge pipe is connected to the accident pool.

[0012] Preferably, a vent silencer is provided between the pressure sensor and the first emergency shut-off valve.

[0013] Preferably, a second tee is provided between the second check valve and the circulation tank, and the third end of the second tee is connected to the inlet of the middle and upper oxidation pipeline of the desulfurization tower through a second control valve.

[0014] The utility model also includes a PLC controller, a signal input end of the PLC controller is connected to a temperature sensor, a pressure sensor and a timer, and a signal output end of the PLC controller is respectively connected to a magnetic suspension blower, a Roots blower and a first emergency shut-off valve.

[0015] An energy-saving oxidation device for ammonia desulfurization of boiler flue gas is manufactured according to the above scheme. The utility model is based on the cooperation between the desulfurization tower and the circulation tank in the prior art, and replaces the traditional Roots blower with a magnetic levitation blower to achieve the purpose of energy saving and consumption reduction. At the same time, a non-return and anti-blocking unit is provided to prevent the solution in the desulfurization tower and other equipment from entering the pipeline and the energy-saving blower unit, thereby achieving the purpose of stable operation of the system and increasing the service life of the magnetic levitation blower; further, the utility model can avoid the vibration of the equipment caused by frequency changes during air supply by arranging a corrugated compensator, so as to ensure the stable operation of the equipment and increase the service life of related equipment. By arranging a pipeline liquid discharge pipeline and an accident pool, it can be achieved that when there is a solution in the pipeline, it is emptied in time, thereby avoiding the defect of ammonium sulfite and ammonium bisulfite crystallizing in the pipeline and causing blockage. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the utility model.

[0017] Figure 2 This is the control principle diagram of the utility model.

[0018] In the figure: 1. desulfurization tower; 2. circulation tank; 3. air oxidation pipeline; 4. magnetic levitation fan; 5. Roots blower; 6. timer; 7. first control valve; 8. automatic vent valve; 9. cooling air exhaust pipeline; 10. first check valve; 11. second check valve; 12. temperature sensor; 13. pressure sensor; 14. first emergency shut-off valve; 15. bellows compensator; 16. first three-way valve; 17. second emergency shut-off valve; 18. accident pool; 19. vent silencer; 20. second three-way valve; 21. second control valve; 22. PLC controller. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0020] Reference Figure 1 As shown, an energy-saving oxidation device for ammonia desulfurization of boiler flue gas includes a desulfurization tower 1 and a circulation tank 2 that cooperates with the desulfurization tower 1 to achieve circulation and desulfurization. An air oxidation pipeline 3 is connected to the desulfurization tower 1 and the circulation tank 2 through an energy-saving fan unit and a non-return and anti-blocking unit respectively; the energy-saving fan unit includes at least one magnetic levitation fan 4. The desulfurization tower 1 described in the utility model is connected to the circulation tank 2, and the desulfurization liquid inside it circulates between the desulfurization tower 1 and the circulation tank 2 to achieve desulfurization of the flue gas. During the oxidation process, the air oxidation pipeline 3 provides air to the desulfurization tower and the circulation tank through the energy-saving fan unit to achieve oxidation; when the air volume and pressure of the magnetic levitation fan 4 and the traditional Roots blower remain unchanged, the high-speed permanent magnet motor and the high-efficiency fluid mechanical system and the magnetic levitation bearing and other technologies achieve high efficiency and energy saving, intelligent control, thereby achieving the characteristics of energy saving and consumption reduction; the magnetic levitation fan 4 has the characteristics of energy saving and consumption reduction compared with the traditional Roots blower, and the structure of the magnetic levitation fan 4 is a well-known technology, so it will not be repeated; when the solution in the desulfurization tower and other equipment enters the pipeline, it will cause the pipeline to be blocked, and when the solution enters the magnetic levitation fan 4, it will cause it to be scrapped; based on the above technical problems, the utility model sets a check unit to prevent the solution in the desulfurization tower and other equipment from entering the pipeline and the energy-saving fan unit, thereby achieving the purpose of stable operation of the system and increasing the service life of the magnetic levitation fan.

[0021] Furthermore, the energy-saving fan unit includes three fans arranged in parallel, one of which is a magnetic levitation fan 4, and two of which are Roots blowers 5; the air oxidation duct 3 is respectively connected to the above three fans, and a first control valve 7 is respectively provided between the outlet end of the three fans and the check and anti-blocking unit. The utility model can select the number of fans to be turned on according to the actual operating conditions. It should be noted that in order to achieve the characteristics of energy saving, when the system is running, it is preferred to turn on the magnetic levitation fan 4 first, and when the oxygen demand is large, a Roots blower 5 can be turned on to cooperate with the magnetic levitation fan 4; and the other Roots blower 5 is a standby to ensure the long-term stable operation of the entire system. That is: when the utility model is running, the magnetic levitation fan 4 is always in operation, and at least one of the two Roots blowers 5 is in standby.

[0022] Furthermore, a venting pipe with an automatic venting valve 8 is provided at the upper part of the magnetic levitation fan 4, and a cooling air exhaust pipe 9 for cooling the magnetic levitation fan is provided at the lower part of the magnetic levitation fan 4. When the system does not need air or is in the startup state, in order to ensure that the startup speed of the magnetic levitation fan 4 is steadily increased, the automatic venting valve 8 can realize the automatic venting of air. In addition, part of the air entering the magnetic levitation fan 4 is used as cooling air of the magnetic levitation fan 4, passes through the relevant heat-generating components inside the magnetic levitation fan 4, and is finally discharged through the cooling air exhaust pipe 9. The above arrangement can realize the long-term stable operation of the magnetic levitation fan 4.

[0023] Furthermore, the non-return and anti-blocking unit includes a first non-return valve 10 arranged at the outlet end of the energy-saving fan unit, and a second non-return valve 11 arranged on the air intake pipe in front of the desulfurization tower 1 and the circulation tank 2. A temperature sensor 12, a pressure sensor 13 and a first emergency shut-off valve 14 are arranged in sequence between the first non-return valve 10 and the second non-return valve 11. The utility model can prevent the solution in the desulfurization tower and other equipment from entering the pipeline and the energy-saving fan unit by arranging the first non-return valve 10 and the second non-return valve 11. Further, by arranging the temperature sensor 12 and the pressure sensor 13, it can detect whether the solution enters the pipeline and whether a blockage problem occurs. Specifically, when the temperature detected by the temperature sensor 12 increases, or the pressure detected by the pressure sensor 13 increases, it can be determined that the solution is backflowing or a blockage problem occurs. At this time, it can be

[0024] Furthermore, a bellows compensator 15 is provided between the first check valve 10 and the temperature sensor 12. The bellows compensator 15 in the utility model is a bellows. When the gas flows through the pipeline, due to the particularity of the bellows structure, pressure waves are generated inside the pipeline. These pressure waves will cause elastic deformation of the bellows. These elastic deformations effectively absorb the vibration of the transmission equipment, reduce the impact on nearby stationary equipment and pipelines, and achieve long-term stable operation of the equipment.

[0025] Furthermore, a first tee 16 is provided between the first emergency shut-off valve 14 and the second check valve 11, and a pipeline accumulated liquid discharge pipe with a second emergency shut-off valve 17 is provided at the third end of the first tee 16, and the end of the pipeline accumulated liquid discharge pipe is connected to the accident pool 18. The above arrangement enables the accumulated liquid entering the pipeline to be quickly discharged through the pipeline accumulated liquid discharge pipe with the second emergency shut-off valve 17, thereby preventing the accumulated liquid from crystallizing and thereby clogging the pipeline.

[0026] Furthermore, a venting silencer 19 is provided between the pressure sensor 13 and the first emergency shut-off valve 14. During abnormal venting, the venting silencer 19 can reduce on-site noise.

[0027] Furthermore, a second tee 20 is provided between the second check valve 11 and the circulation tank 2, and the third end of the second tee 20 is connected to the inlet of the middle and upper oxidation pipeline of the desulfurization tower 1 through the second control valve 21. By providing the second control valve 21, it is possible to send air into the desulfurization tower 1 when the circulation tank cannot be fully oxidized to achieve the characteristic of fully sulfiding the flue gas.

[0028] Reference Figure 1 , 2 As shown, the utility model also includes a PLC controller 22, the signal input end of the PLC controller 22 is connected to the temperature sensor 12, the pressure sensor 13 and the timer 6, and the signal output end of the PLC controller 22 is respectively connected to the magnetic suspension blower 4, the Roots blower 5 and the first emergency shut-off valve 14. When the temperature detected by the temperature sensor 12 and / or the pressure sensor 13 is too high or the pressure is too high, the PLC controller 22 controls the first emergency shut-off valve 14 to close, the timer 6 starts timing, and after a delay of several seconds, the PLC controller 22 controls the opened magnetic suspension blower 4 and the Roots blower 5 to close. The above control method can prevent the solvent from entering the blower and causing damage to the blower.

[0029] The working principle of the utility model is as follows: the desulfurization tower 1 is connected to the circulation tank 2, and the desulfurization liquid inside the desulfurization tower 1 circulates between the desulfurization tower 1 and the circulation tank 2 to realize the desulfurization of the flue gas; at the same time, the magnetic suspension fan 4 is started. In the startup state, in order to ensure that the startup speed of the magnetic suspension fan 4 is steadily increased, an automatic vent valve 8 is set to realize the automatic venting of the air. In addition, a part of the air entering the magnetic suspension fan 4 is used as the cooling air of the magnetic suspension fan 4, which passes through the relevant heating components inside the magnetic suspension fan 4 and is finally discharged through the cooling air exhaust pipe 9; the above method can ensure the continuous and stable operation of the magnetic suspension fan 4, and the suspension fan 4 sends air into the circulation tank 2 through the non-return anti-blocking unit. When the circulation tank cannot be fully oxidized, the air enters the desulfurization tower 1 at the same time when the second control valve 21 is opened to achieve full oxidation and desulfurization of the flue gas. At the same time, the utility model can choose to use a Roots blower 5 to cooperate with the magnetic suspension blower 4 to supply air according to the working conditions, or use the magnetic suspension blower 4 alone to supply air. When the solution in the desulfurization tower and other equipment enters the pipeline during operation, the first emergency shut-off valve 14 can be closed by manual control or automatic control, and the corresponding started blower can be closed after closing the first emergency shut-off valve 14 to achieve the purpose of protecting the magnetic suspension blower 4. The manual control process will not be repeated. When automatic control is required, when the temperature detected by the temperature sensor 12 and / or the pressure sensor 13 is too high or the pressure is too high, the PLC controller 22 controls the first emergency shut-off valve 14 to close, and the timer 23 starts timing. After a delay of several seconds, the PLC controller 22 controls the opened magnetic suspension blower 4 and Roots blower 5 to close. By comparing the technical solution of the utility model with the traditional technical solution, the power saving reaches 30% of the original. By setting the non-return and anti-blocking unit, the long-term stable operation of the system can be achieved, and the service life of the magnetic suspension fan 4 is guaranteed.

[0030] 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. An energy-saving oxidation device for ammonia desulfurization of boiler flue gas, comprising a desulfurization tower (1) and a circulation tank (2) that cooperates with the desulfurization tower (1) to achieve circulation and desulfurization, characterized in that: The air oxidation pipeline (3) is connected to the desulfurization tower (1) and the circulation tank (2) respectively through an energy-saving fan unit and a non-return and anti-blocking unit; The energy-saving fan unit comprises three fans arranged in parallel, one of which is a magnetic suspension fan (4) and two of which are Roots fans (5); the air oxidation pipeline (3) is respectively connected to the three fans, and a first control valve (7) is respectively provided between the outlet ends of the three fans and the check and anti-blocking unit; The non-return and anti-blocking unit comprises a first non-return valve (10) arranged at the outlet end of the energy-saving fan unit, and a second non-return valve (11) arranged on the air intake pipe in front of the desulfurization tower (1) and the circulation tank (2), and a temperature sensor (12), a pressure sensor (13) and a first emergency shut-off valve (14) are arranged in sequence between the first non-return valve (10) and the second non-return valve (11).

2. The energy-saving oxidation device for boiler flue gas ammonia desulfurization according to claim 1 is characterized in that: The upper part of the magnetic levitation fan (4) is provided with a venting pipeline with an automatic venting valve (8), and the lower part of the magnetic levitation fan (4) is provided with a cooling air exhaust pipeline (9) for cooling the magnetic levitation fan.

3. The energy-saving oxidation device for boiler flue gas ammonia desulfurization according to claim 1 is characterized in that: A bellows compensator (15) is provided between the first check valve (10) and the temperature sensor (12).

4. The energy-saving oxidation device for boiler flue gas ammonia desulfurization according to claim 1 is characterized in that: A first tee (16) is provided between the first emergency shut-off valve (14) and the second check valve (11); a pipeline accumulated liquid discharge pipe is provided at the third end of the first tee (16); a second emergency shut-off valve (17) is provided on the pipeline accumulated liquid discharge pipe; and a terminal end of the pipeline accumulated liquid discharge pipe is connected to an accident pool (18).

5. The energy-saving oxidation device for boiler flue gas ammonia desulfurization according to claim 1 is characterized in that: A vent silencer (19) is provided between the pressure sensor (13) and the first emergency shut-off valve (14).

6. The energy-saving oxidation device for boiler flue gas ammonia desulfurization according to claim 1 is characterized in that: A second tee (20) is provided between the second check valve (11) and the circulation tank (2), and a third end of the second tee (20) is connected to the inlet of the middle and upper oxidation pipeline of the desulfurization tower (1) through a second control valve (21).

7. The energy-saving oxidation device for boiler flue gas ammonia desulfurization according to claim 1 is characterized in that: It also includes a PLC controller (22), wherein a signal input end of the PLC controller (22) is connected to the temperature sensor (12), the pressure sensor (13) and the timer (6), and a signal output end of the PLC controller (22) is respectively connected to the magnetic suspension blower (4), the Roots blower (5) and the first emergency shut-off valve (14).

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