Oxidation fan system

Abstract

The invention relates to the technical field of flue gas desulfurization and energy conservation, and discloses an oxidation fan system which is characterized in that a variable-frequency centrifugal fan unit inputs oxidation air into a slurry pond; the calcium sulfite concentration tester obtains the concentration value of calcium sulfite from the slurry pond; the dissolved oxygen meter obtains a dissolved oxygen concentration value from the slurry pond; when the concentration value of calcium sulfite is less than or equal to 0.01 mmol / L and the concentration value of dissolved oxygen is more than 0.6 mg / L, the oxidation fan system reduces the output frequency; when the concentration value of calcium sulfite is less than or equal to 0.01 mmol / L and the concentration value of dissolved oxygen is less than 0.6 mg / L, the output frequency is improved; when the concentration value of calcium sulfite is less than or equal to 0.01 mmol / L and the concentration value of dissolved oxygen is 0.6 mg / L, the output frequency is maintained. The variable-frequency centrifugal fan unit is combined with the calcium sulfite concentration value and the dissolved oxygen concentration value, the output frequency of the variable-frequency centrifugal fan unit is adjusted, air volume adjustment is achieved, and the energy-saving effect is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of flue gas desulfurization energy saving, and in particular to an oxidation fan system. Background Art

[0002] In coal-fired power plants, limestone-gypsum wet flue gas desulfurization systems are generally used to desulfurize raw flue gas. In the process of desulfurizing raw flue gas, an oxidation fan system is generally required to supply oxygen to the limestone-gypsum wet flue gas desulfurization system. The energy consumption of the oxidation fan system accounts for about 15% of the energy consumption in the desulfurization process, and is an important part of the desulfurization energy consumption.

[0003] The high energy consumption of the oxidation fan system is mainly caused by the following reasons: the design margin of the oxidation fan in the oxidation fan system is large, and the air volume of the oxidation fan cannot be adjusted. The selection of the oxidation fan is generally designed according to the maximum load and the worst working conditions of the unit; currently, the load rate of most units is low, and the actual operating conditions often deviate from the design conditions, resulting in a series of problems such as over-oxidation of the circulating slurry in the slurry pool at the bottom of the desulfurization absorption tower and excessive overall power consumption. Summary of the invention

[0004] In view of this, the present invention provides an oxidation blower system to solve the problem of high energy consumption of the oxidation blower system in the process of desulfurizing raw flue gas using a limestone-gypsum wet desulfurization system.

[0005] The present invention provides an oxidation fan system, comprising: The variable frequency centrifugal fan unit inputs oxidation air into the slurry pool provided at the bottom of the desulfurization absorption tower through the oxidation air duct; firstly, the oxidation air demand is determined according to the flow rate of the original flue gas input to the desulfurization absorption tower, the concentration of sulfur dioxide in the original flue gas and the oxidation air utilization rate; then, the initial output frequency of the variable frequency centrifugal fan unit is determined according to the oxidation air demand; A calcium sulfite concentration tester is connected to the variable frequency centrifugal fan unit signal, and the calcium sulfite concentration tester is suitable for sampling from the first sampling port of the slurry pool to obtain the concentration value of calcium sulfite; A dissolved oxygen meter, connected to the variable frequency centrifugal fan unit signal, the dissolved oxygen meter is suitable for sampling from the second sampling port of the slurry pool to obtain the dissolved oxygen concentration value; The oxidation fan system is suitable for reducing the output frequency of the variable frequency centrifugal fan unit to reduce the amount of oxidation air when the concentration value of calcium sulfite is ≤0.01mmol / L and the dissolved oxygen concentration value is greater than 0.6mg / L; or increasing the output frequency of the variable frequency centrifugal fan unit to increase the amount of oxidation air when the concentration value of calcium sulfite is ≤0.01mmol / L and the dissolved oxygen concentration value is less than 0.6mg / L; or maintaining the output frequency of the variable frequency centrifugal fan unit when the concentration value of calcium sulfite is ≤0.01mmol / L and the dissolved oxygen concentration value is 0.6mg / L. Beneficial effect: The present application adopts the above technical scheme, fully utilizes the advantages of the variable frequency centrifugal fan unit with adjustable air volume, high efficiency and low energy consumption, combines the online measurement of the concentration value of calcium sulfite and the dissolved oxygen concentration value, and corrects and adjusts the output frequency of the variable frequency centrifugal fan unit, which can realize the precise adjustment of the air volume of the variable frequency centrifugal fan unit, plays a role of high efficiency and energy saving, and has good energy-saving and environmental protection benefits.

[0006] Optionally, it also includes: a slurry pump, one end of which is connected to the second sampling port; A gypsum slurry cyclone, one end of which is connected to the other end of the slurry pump; The clarifier has one end connected to the overflow port of the gypsum slurry cyclone; the clarifier is also connected to the dissolved oxygen meter. Beneficial effect: The present application adopts the above technical solution, uses the gypsum slurry cyclone combined with the clarifier to reduce the solid content of the slurry, and significantly improves the test accuracy of the dissolved oxygen meter.

[0007] Optionally, the first sampling port is located below the oxidation air duct, and the second sampling port is located above the oxidation air duct.

[0008] Optionally, the slurry at the bottom of the gypsum slurry cyclone is returned to the desulfurization absorption tower through a trench combined with a pit pump. Beneficial effects: The present application adopts the above technical solution to recycle the slurry and reduce costs.

[0009] Optionally, it also includes: A primary air breaking structure, wherein a plurality of nozzle assemblies are arranged at intervals in the portion of the oxidation air duct located in the slurry pool; the nozzle assemblies are suitable for spraying oxidation air downward; the primary air breaking structure is arranged below each nozzle assembly; the primary air breaking structure is suitable for performing a primary breaking of the oxidation air sprayed from the nozzle assembly; The secondary air breaking structure is arranged above the portion of the oxidation air duct located in the slurry pool; the secondary air breaking structure is suitable for secondary breaking the rising oxidation air. Beneficial effect: The present application adopts the above technical solution, and breaks the large bubbles in the oxidation air into small bubbles through the primary air breaking structure and the secondary air breaking structure, which significantly increases the contact area and contact time between the bubbles and the desulfurization slurry, significantly improves the utilization rate of the oxidation air, and further reduces the energy consumption of the oxidation fan system.

[0010] Optionally, the primary air crushing structure comprises: The two first orifice plates arranged at an angle are connected to the oxidation air duct via a first connecting piece, and the nozzle assembly is located on the inner side of the angle.

[0011] Optionally, the angle is 90 degrees.

[0012] Optionally, the secondary air crushing structure includes: The second orifice plate is horizontally arranged and connected to the oxidation air duct through a second connecting piece.

[0013] Optionally, the first connecting member is two first rib plates, and the two first orifice plates are respectively connected to the oxidation air duct through the first rib plates; the second connecting member is three second rib plates arranged at an angle.

[0014] Optionally, the nozzle assembly comprises: A first nozzle is arranged downward in a vertical direction; The second nozzle is arranged downward in the vertical direction, and the length of the second nozzle is greater than the length of the first nozzle. Beneficial effect: The present application adopts the above technical solution, when the first nozzle is blocked, the oxidizing air is ejected from the second nozzle, avoiding the problem of incomplete slurry oxidation caused by the blockage of the first nozzle, and effectively preventing the pressure of the oxidizing air from further rising, thereby significantly improving the safety and energy efficiency of the oxidation fan system. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 A schematic diagram of the connection structure of the oxidation fan system provided in an embodiment of the present invention; Figure 2 A schematic diagram of a partial cross-sectional structure of an oxidation blower system provided in an embodiment of the present invention; Figure 3 It is a partial front view structural schematic diagram of the oxidation blower system provided in an embodiment of the present invention.

[0017] Description of reference numerals: 1. The first variable frequency centrifugal fan; 2. The second variable frequency centrifugal fan; 3. The oxidation air duct; 4. The desulfurization absorption tower; 5. The slurry pool; 6. The original flue gas; 7. The calcium sulfite concentration tester; 8. The first sampling port; 9. The dissolved oxygen meter; 10. The second sampling port; 11. The slurry pump; 12. The gypsum slurry cyclone; 13. The clarification tank; 14. The primary air breaking structure; 15. The secondary air breaking structure; 16. The first orifice plate; 17. The second orifice plate; 18. The first rib plate; 19. The second rib plate; 20. The first nozzle; 21. The second nozzle; 22. The ditch; 23. The purified flue gas. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 those skilled in the art without creative work are within the scope of protection of the present invention.

[0019] The efficiency of the oxidation fan in supplying oxygen to the slurry pool through the oxidation air duct is low. The bubbles of the oxidation air after entering the slurry are large. A large amount of oxidation air does not have time to dissolve into the slurry and escapes into the purified flue gas, resulting in a low utilization rate of the oxidation air. In order to ensure the oxygen supply, it is necessary to increase the operating power of the oxidation fan, resulting in increased energy consumption. The existing conventional pipe network oxidation air branch pipe generally adopts a 2205 material steel pipe with a diameter of 157 mm, and the air outlet is a small hole with a nominal diameter range of 20 mm to 25 mm. The air bubbles at the above air outlet are large, and most of the oxidation air escapes from the slurry into the flue gas. It is also due to the above reasons that the present application proposes an improved oxidation fan system.

[0020] like Figures 1 to 3 A specific implementation of the oxidation fan system shown includes: a variable frequency centrifugal fan unit, a calcium sulfite concentration tester 7, a dissolved oxygen meter 9, a slurry pump 11, a gypsum slurry cyclone 12, a clarifier 13, a primary air crushing structure 14 and a secondary air crushing structure 15. Specifically, the variable frequency centrifugal fan unit can be a first variable frequency centrifugal fan 1 and a second variable frequency centrifugal fan 2 arranged in parallel. The first variable frequency centrifugal fan 1 and the second variable frequency centrifugal fan 2 are both magnetically suspended variable frequency oxidation fans. The oxidation fan system described in the present application is applied to a limestone-gypsum wet desulfurization system.

[0021] like Figure 1 As shown, the variable frequency centrifugal fan unit inputs oxidation air into the slurry pool 5 provided at the bottom of the desulfurization absorption tower 4 through the oxidation air duct 3; the oxidation air duct 3 is installed within 4.5~5.0m below the liquid level of the slurry pool 5. First, the oxidation air demand is determined according to the flow rate of the original flue gas 6 input to the desulfurization absorption tower 4, the concentration of sulfur dioxide in the original flue gas 6 and the oxidation air utilization rate; then the initial output frequency of the variable frequency centrifugal fan unit is determined according to the oxidation air demand. The original flue gas 6 contains 6% oxygen under standard dry conditions, and the oxidation air utilization rate can be 30%. The purified flue gas 23 is discharged from the top of the desulfurization absorption tower 4. Figure 1 The arrow on the left side of the figure indicates the flow direction of the original flue gas 6. Figure 1The arrow in the upper middle part indicates the flow direction of the purified flue gas 23. The calcium sulfite concentration tester 7 is connected to the signal of the variable frequency centrifugal fan unit, and the calcium sulfite concentration tester 7 is suitable for sampling from the first sampling port 8 of the slurry pool 5 online in real time to obtain the concentration value of calcium sulfite. Specifically, the first sampling port 8 is located below the oxidation air duct 3. One end of the slurry pump 11 is connected to the second sampling port 10; one end of the gypsum slurry cyclone 12 is connected to the other end of the slurry pump 11; one end of the clarification tank 13 is connected to the overflow port provided in the gypsum slurry cyclone 12; the solid content of the slurry overflowing from the overflow port is less than 3%. The clarification tank 13 is also connected to the dissolved oxygen meter 9. The dissolved oxygen meter 9 is connected to the signal of the variable frequency centrifugal fan unit. The dissolved oxygen meter 9 can take samples from the second sampling port 10 of the slurry pool 5 online in real time to obtain the dissolved oxygen concentration value; or the dissolved oxygen meter 9 can also take samples from the clarification tank 13 online in real time to obtain the dissolved oxygen concentration value. The dissolved oxygen meter 9 is often used for dissolved oxygen content testing of water samples in chemical majors. There are certain requirements for the turbidity of water quality. If the turbidity is too high, it will affect its measurement accuracy. The present application can pump a slurry with a solid content of about 15% into the gypsum slurry cyclone 12 through a slurry pump 11. The solid content of the overflow slurry after cyclone is ≤1%, which meets the use requirements of the dissolved oxygen meter 9 and significantly improves the test accuracy. Specifically, the second sampling port 10 is located above the oxidation air duct 3, and the second sampling port 10 can be set at different typical positions above the oxidation air duct 3. Furthermore, the slurry at the bottom of the gypsum slurry cyclone 12 is returned to the desulfurization absorption tower 4 through the ditch 22 combined with the pit pump; the solid content of the slurry at the bottom of the gypsum slurry cyclone 12 is above 75%. The oxidation fan system is suitable for reducing the output frequency of the variable frequency centrifugal fan unit to reduce the amount of oxidation air when the concentration value of calcium sulfite is ≤0.01mmol / L and the dissolved oxygen concentration value is >0.6mg / L; or when the concentration value of calcium sulfite is ≤0.01mmol / L and the dissolved oxygen concentration value is <0.6mg / L, the output frequency of the variable frequency centrifugal fan unit is increased to increase the amount of oxidation air; or when the concentration value of calcium sulfite is ≤0.01mmol / L and the dissolved oxygen concentration value is 0.6mg / L, the output frequency of the variable frequency centrifugal fan unit is maintained. The concentration value of calcium sulfite and the dissolved oxygen concentration value reflect the operating conditions of the limestone-gypsum wet desulfurization system. The reason why 0.01mmol / L is taken as a special value point of calcium sulfite concentration is that when the oxidation rate of calcium sulfite in the slurry reaches more than 95%, the concentration value of calcium sulfite is ≤0.01mmol / l, and the gypsum quality at this time meets the emission standards of coal-fired power plants.The output frequency of the variable frequency centrifugal fan unit can be adjusted in steps of 1 Hz to make the concentration of calcium sulfite ≤ 0.01 mmol / L; and then the output frequency of the variable frequency centrifugal fan unit can be adjusted in steps of 0.2 Hz to maintain the dissolved oxygen concentration at 0.6 mg / L. Specifically, the dissolved oxygen concentration value can be obtained every 180 seconds. The handheld calcium sulfite concentration tester can be modified to add a remote transmission module to obtain the calcium sulfite concentration tester 7 described in the present application, and the first sampling port 8 can be set 0.5 m below the oxidation air duct 3. SO. 3 2- Oxidized to SO 4 2- After that, the molecular weight of the formed gypsum is greater than that of calcium sulfite, and the gypsum is precipitated to the bottom of the slurry pool 5. Through the above-mentioned position setting of the first sampling port 8, the SO in the slurry can be understood. 3 2- The actual degree of oxidation is representative.

[0022] like Figure 2 and Figure 3 As shown, a plurality of nozzle assemblies are arranged at intervals in the portion of the oxidation air duct 3 located in the slurry pool 5; the nozzle assemblies are suitable for spraying oxidation air downward; the primary air crushing structure 14 is arranged below each nozzle assembly; the primary air crushing structure 14 is suitable for crushing the oxidation air sprayed from the nozzle assembly once. The secondary air crushing structure 15 is arranged above the portion of the oxidation air duct 3 located in the slurry pool 5; the secondary air crushing structure 15 is suitable for crushing the rising oxidation air twice.

[0023] Specifically, the primary air breaking structure 14 includes: two first orifice plates 16 arranged at an angle, connected to the oxidation air duct 3 through a first connecting piece, and the nozzle assembly is located on the inner side of the angle. The angle can be 90 degrees, the two first orifice plates 16 are symmetrically arranged, and the nozzle assembly is basically located at the symmetry center of the two first orifice plates 16. The secondary air breaking structure 15 includes: a horizontally arranged second orifice plate 17, and the second orifice plate 17 is connected to the oxidation air duct 3 through a second connecting piece. More specifically, the first connecting piece is two first rib plates 18, and the two first orifice plates 16 are respectively connected to the oxidation air duct 3 through the first rib plates 18; the second connecting piece is three second rib plates 19 arranged at an angle. The first orifice plate 16 and the second orifice plate 17 can both be 2205 stainless steel plates. After the oxidizing air is ejected from the nozzle assembly, it is first broken by the primary air breaking structure 14. Most of the large bubbles become small bubbles after passing through the first orifice plate 16. A small part of the large bubbles pass through the diversion effect of the primary air breaking structure 14 and then pass through the breaking effect of the secondary air breaking structure 15. The bubbles are further reduced in size and most of the large bubbles become small bubbles, which significantly increases the contact area between the oxidizing air and the desulfurization slurry, and at the same time increases the residence time of the bubbles in the slurry, which significantly improves the utilization rate of the oxidizing air.

[0024] Specifically, the nozzle assembly includes: a first nozzle 20 and a second nozzle 21. The nominal diameters of the first nozzle 20 and the second nozzle 21 may be 20 mm. The first nozzle 20 is arranged downward in the vertical direction. The second nozzle 21 is arranged downward in the vertical direction, and the length of the second nozzle 21 is greater than the length of the first nozzle 20. The second nozzle 21 is more than 30 cm longer than the first nozzle 20. When the slurry density is 1200 kg / m 3 The outlet pressure of the second nozzle 21 is higher than the outlet pressure of the first nozzle 20 by 3.6 kPa; when the first nozzle 20 is blocked, the pressure of the oxidation air rises, and when the pressure rise is increased by more than 3.6 kPa, the oxidation air is ejected from the second nozzle 21, avoiding the problem of incomplete oxidation of the slurry caused by the blockage of the first nozzle 20, thereby significantly improving the safety and energy efficiency of the oxidation blower system.

[0025] During the oxidation process of the desulfurization circulating slurry, oxidizing air is introduced, and part of the oxidizing air and the slurry undergo gas-liquid two-phase mass transfer, and part of the oxidizing air dissolved in the slurry reacts with SO 3 2- Oxidation reaction without SO 3 2- The oxidizing air that reacts is the one that maintains SO 3 2-The driving force of the oxidation reaction, while the oxidizing air dissolved in the slurry is a small part, and most of the oxidizing air finally overflows the slurry pool and mixes with the original flue gas 6. The greater the amount of bubbles dissolved in the slurry, the greater the effect on SO 3 2- The higher the driving force of oxidation reaction, the higher the utilization rate of oxidation air, the smaller the bubbles sprayed by the nozzle assembly, the larger the contact area between oxidation air and slurry, and the higher the amount dissolved in slurry. Therefore, breaking the bubbles of oxidation air and improving the utilization rate of oxidation air are important measures to improve the economy of oxidation fan system.

[0026] The existing desulfurization system of a certain 660MW unit is a single-tower system. The oxidation air system adopts Roots blowers, two for use and one for backup. The oxidation air duct adopts a pipe network structure combined with a pulse suspension pump. The power consumption of a single oxidation blower is 255kWh / h, and the power consumption of two oxidation blowers is 510kWh / h. The oxidation air duct is often blocked or broken, and the slurry is not fully oxidized, which often makes it difficult to dehydrate gypsum. The above oxidation blower system is modified by adopting the technical solution of the present application, three Roots blowers are removed and replaced with two variable frequency centrifugal blowers, a set of calcium sulfite concentration tester 7 and dissolved oxygen meter 9 are added, the slurry is led out two meters below the overflow port of the desulfurization absorption tower 4, and introduced into a cyclone of the gypsum slurry cyclone 12 through the slurry pump 11, and the overflow port of the gypsum slurry cyclone 12 is separately introduced into the newly added clarification tank 13 or clarification tank, and the dissolved oxygen meter 9 is installed in the clarification tank 13 or clarification tank, and the signal is connected to the PLC control system of the variable frequency centrifugal blower, and the flow rate of the original flue gas 6, the concentration of sulfur dioxide in the original flue gas 6 and the signal of the oxidation air utilization rate are connected to the PLC control system, and the output frequency of the variable frequency centrifugal blower is determined in combination with the above-mentioned online real-time obtained calcium sulfite concentration value and dissolved oxygen concentration value. The oxidation air duct 3 is equipped with a primary air crushing structure 14 and a secondary air crushing structure 15. In combination with the present application plan, after the transformation is completed, the energy consumption of a single variable frequency centrifugal fan is reduced to 165kWh / h, and the power consumption of two variable frequency centrifugal fans is 330kWh / h, and the energy consumption is reduced by more than 35%, significantly reducing the factory power consumption rate; the blockage phenomenon of the oxidation air duct 3 is also significantly alleviated.

[0027] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. An oxidation fan system, characterized in that: include: The variable frequency centrifugal fan unit inputs oxidation air into a slurry pool (5) provided at the bottom of a desulfurization absorption tower (4) through an oxidation air duct (3); firstly, the oxidation air demand is determined according to the flow rate of the original flue gas (6) input into the desulfurization absorption tower (4), the concentration of sulfur dioxide in the original flue gas (6) and the oxidation air utilization rate; and then, the initial output frequency of the variable frequency centrifugal fan unit is determined according to the oxidation air demand; A calcium sulfite concentration tester (7) is connected to the variable frequency centrifugal fan unit by signal, and the calcium sulfite concentration tester (7) is suitable for sampling from the first sampling port (8) of the slurry pool (5) to obtain the concentration value of calcium sulfite; A dissolved oxygen meter (9) is connected to the variable frequency centrifugal fan unit by signal, and the dissolved oxygen meter (9) is suitable for sampling from the second sampling port (10) of the slurry pool (5) to obtain a dissolved oxygen concentration value; The oxidation fan system is suitable for reducing the output frequency of the variable frequency centrifugal fan unit to reduce the amount of oxidation air when the concentration value of calcium sulfite is ≤0.01mmol / L and the dissolved oxygen concentration value is greater than 0.6mg / L; or increasing the output frequency of the variable frequency centrifugal fan unit to increase the amount of oxidation air when the concentration value of calcium sulfite is ≤0.01mmol / L and the dissolved oxygen concentration value is less than 0.6mg / L; or maintaining the output frequency of the variable frequency centrifugal fan unit when the concentration value of calcium sulfite is ≤0.01mmol / L and the dissolved oxygen concentration value is 0.6mg / L.

2. The oxidation blower system according to claim 1, characterized in that: Also includes: A slurry pump (11), one end of which is connected to the second sampling port (10); A gypsum slurry cyclone (12), one end of which is connected to the other end of the slurry pump (11); A clarification tank (13) has one end connected to an overflow port provided on the gypsum slurry cyclone (12); the clarification tank (13) is also connected to the dissolved oxygen meter (9).

3. The oxidation blower system according to claim 1, characterized in that: The first sampling port (8) is located below the oxidation air duct (3), and the second sampling port (10) is located above the oxidation air duct (3).

4. The oxidation blower system according to claim 2, characterized in that: The slurry at the bottom of the gypsum slurry cyclone (12) is returned to the desulfurization absorption tower (4) through a ditch (22) in combination with a pit pump.

5. The oxidation blower system according to any one of claims 1 to 4, characterized in that: Also includes: A primary air breaking structure (14), wherein a plurality of nozzle assemblies are provided at intervals in the portion of the oxidation air duct (3) located in the slurry pool (5); the nozzle assemblies are adapted to spray oxidation air downward; the primary air breaking structure (14) is provided below each nozzle assembly; the primary air breaking structure (14) is adapted to perform primary breaking on the oxidation air sprayed from the nozzle assembly; The secondary air crushing structure (15) is arranged above the portion of the oxidation air duct (3) located in the slurry pool (5); the secondary air crushing structure (15) is suitable for performing secondary crushing on the rising oxidation air.

6. The oxidation blower system according to claim 5, characterized in that: The primary air crushing structure (14) comprises: Two first orifice plates (16) arranged at an angle are connected to the oxidation air duct (3) via a first connecting piece, and the nozzle assembly is located on the inner side of the angle.

7. The oxidation blower system according to claim 6, characterized in that: The angle is 90 degrees.

8. The oxidation blower system according to claim 6, characterized in that: The secondary air crushing structure (15) comprises: A second orifice plate (17) arranged horizontally is connected to the oxidation air duct (3) via a second connecting piece.

9. The oxidation blower system according to claim 8, characterized in that: The first connecting member is two first rib plates (18), and the two first orifice plates (16) are respectively connected to the oxidation air duct (3) via the first rib plates (18); the second connecting member is three second rib plates (19) arranged at an angle.

10. The oxidation blower system according to claim 5, characterized in that: The nozzle assembly comprises: A first nozzle (20) is arranged downward in a vertical direction; The second nozzle (21) is arranged downward in a vertical direction, and the length of the second nozzle (21) is greater than the length of the first nozzle (20).

Images