Iron sludge recycling fenton fluidized bed
By integrating oxidation, coagulation crystallization, and mud-water separation into a Fenton fluidized bed, the problems of large footprint and high cost of iron sludge treatment in Fenton equipment have been solved, achieving resource recycling and improved treatment efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HENAN POLYTECHNIC UNIV
- Filing Date
- 2026-04-09
- Publication Date
- 2026-05-29
Smart Images
Figure CN122102436A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of wastewater treatment technology, and more specifically relates to a Fenton fluidized bed for the reuse of iron sludge. Background Technology
[0002] The Fenton process is a technology that utilizes the interaction of reactants under stirred mixing to generate highly oxidizing hydroxyl radicals, which decompose organic matter in wastewater. The participation of oxygen can improve the generation efficiency of hydroxyl radicals and enhance the degradation efficiency of pollutants. Existing Fenton treatment equipment is mostly laid out horizontally, with components such as pH adjustment tanks, Fenton reaction tanks, neutralization reaction tanks, degassing reaction tanks, flocculation tanks, and sedimentation tanks connected by pipelines. This results in a large footprint, and the kinetic energy of the water flow is consumed by the pipelines, significantly impacting wastewater treatment efficiency. Furthermore, the iron-rich reactants are consumed in large quantities during the reaction, generating solid waste, Fenton iron sludge, which requires further treatment, greatly increasing wastewater treatment costs.
[0003] Therefore, how to provide a Fenton fluidized bed for the reuse of iron sludge is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention
[0004] In view of this, the present invention provides a Fenton fluidized bed for the reuse of iron sludge, which has the advantages of cost reduction and efficiency improvement.
[0005] To achieve the above objectives, the present invention adopts the following technical solution: A Fenton fluidized bed for reusing iron sludge includes a support, a reactor outer shell, an inner cavity, a stirring device, a wastewater jetting device, an outlet pipe, and a dosing system. The support is located at the bottom of the reactor outer shell. The bottom of the reactor outer shell is connected to the wastewater jetting device. The inner cavity is housed within the reactor outer shell via a frame. The bottom of the inner cavity is connected to the wastewater jetting device via a return pipe. The wastewater jetting device is used to introduce wastewater and air into the inner cavity. The lower end of the stirring device is located within the inner cavity. The dosing system is used for… A reagent is introduced into the interior of the inner cavity and the interior of the reactor outer shell; the outlet pipe is located on one side of the top of the reactor outer shell; the interior of the inner cavity is formed, from bottom to top, into a Fenton fluidized oxidation zone and a coagulation crystallization zone; the gap between the inner cavity and the reactor outer shell is formed, from top to bottom, into a coagulation crystallization sedimentation zone, an acidification reduction zone, and a circulation reflux zone; multiple crystallization reflux channels are uniformly arranged on the side wall of the reflux pipe, connecting the interior of the reactor outer shell and the bottom of the inner cavity; the Fenton fluidized oxidation zone is filled with a fluidized carrier and iron-rich wastewater treatment solid waste.
[0006] Furthermore, the wastewater jet device includes a high-pressure water pump, an inlet pipe, an air inlet pipe, and a nozzle; the output end of the high-pressure water pump is fixedly connected to one end of the nozzle via a flange; the nozzle is connected to the high-pressure water pump via an inlet pipe and an air inlet pipe; the nozzle includes a primary jet mixing zone with a gradually increasing inner diameter and a secondary jet mixing zone with a gradually decreasing inner diameter, and the primary jet mixing zone and the secondary jet mixing zone are fixedly connected via a flange; the secondary jet mixing zone penetrates the reactor shell and connects to the return pipe.
[0007] Furthermore, the top of the inner cavity is provided with a water flow baffle with a pointed tip forming a cone; an inclined tube sedimentation sludge settling zone is provided above the water flow baffle; an inclined tube sedimentation zone is provided above the inclined tube sedimentation sludge settling zone; the water flow baffle is used to block the upward flow of the mixed flow in the coagulation and crystallization zone, with part of it flowing downward into the coagulation and crystallization settling zone and the other part flowing upward into the inclined tube sedimentation sludge settling zone.
[0008] Furthermore, the inclined tube sedimentation zone is provided with several inclined tubes, the bottom of which is fixed inside the reactor shell by a water-passing plate, and the top of which is fixed to the inner wall of the reactor shell by an overflow collection weir.
[0009] Furthermore, the bottom of the inner cavity is set in an arc shape, and the inner wall of the bottom of the reactor outer shell is set in an arc shape, so that the circulation reflux zone enclosed by the bottom of the inner cavity and the inner wall of the bottom of the reactor outer shell forms an arc-shaped region.
[0010] Furthermore, multiple sets of submersible thrust pumps are installed in the circulation reflux zone.
[0011] Furthermore, the outer wall of the reflux pipe is provided with a plurality of uniformly arranged circulation reflux inlets and triangular guide plates, the circulation reflux inlets and triangular guide plates being spaced apart, and the circulation reflux inlets being connected to the crystallization reflux channel.
[0012] Furthermore, the stirring device includes a stirring motor, a rotating shaft, two sets of stirring rods for the coagulation and crystallization zones, and multiple sets of stirring rods for the oxidation zones; the stirring motor is fixedly installed on the top of the reactor outer shell; the upper end of the rotating shaft passes through the reactor outer shell and is fixedly connected to the output shaft of the stirring motor, while the lower end is located inside the inner cavity; the two sets of stirring rods for the coagulation and crystallization zones are installed on the rotating shaft and located in the middle of the inner cavity; the multiple sets of stirring rods for the oxidation zones are installed on the rotating shaft and located at the bottom of the inner cavity.
[0013] Furthermore, an oxidation zone pH monitoring electrode is installed on the rotating shaft inside the Fenton fluidized oxidation zone to monitor the pH value within the Fenton fluidized oxidation zone; a coagulation crystallization zone pH monitoring electrode is also installed on the rotating shaft inside the coagulation crystallization zone to monitor the pH value within the coagulation crystallization zone.
[0014] Furthermore, the dosing system includes a pH adjustment / coagulant / oxidant inlet, a coagulant dosing inlet, a pH adjustment dosing inlet, an oxidant dosing inlet, and an outer ring dosing device. The rotating shaft is hollow, with a pH adjustment / coagulant / oxidant inlet at the top and the coagulant dosing inlet, pH adjustment dosing inlet, and oxidant dosing inlet at the bottom. Multiple sets of coagulant dosing inlets are evenly arranged along a set of stirring rods in the coagulation and crystallization zone. Multiple sets of pH adjustment dosing inlets are evenly arranged below the coagulant dosing inlets and along another set of stirring rods in the coagulation and crystallization zone. The oxidant dosing inlet is located at the bottom end of the rotating shaft. The outer ring dosing device is fixedly sleeved in the middle of the reactor shell, with an acidification and reduction inlet on the outer side and multiple sets of acidification and reduction dosing pipes evenly arranged circumferentially on the inner side, penetrating the side wall of the reactor shell and extending into the interior of the reactor shell.
[0015] The beneficial effects of this invention are as follows: This invention provides a Fenton fluidized bed for the reuse of iron sludge, which integrates oxidation, coagulation and crystallization, mud-water separation, and the recycling of iron sludge and fluidized carrier into a single device. It has a small footprint, good treatment effect, and achieves resource recycling, thus having a significant effect on cost reduction and efficiency improvement. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.
[0017] Figure 1 This is a schematic diagram of the internal structure of the present invention.
[0018] Figure 2 This is a schematic diagram of the internal wastewater flow of the present invention.
[0019] Figure 3 This is a schematic diagram of the reflux pipe of the present invention.
[0020] In the figure: 1-Inlet pipe; 2-Air inlet pipe; 3-High-pressure water pump; 4-Wastewater jet device; 5-Support; 6-Primary jet mixing zone; 7-Secondary jet mixing zone; 8-Return pipe; 9-Oxidant dosing port; 10-Oxidation zone stirring rod; 11-Oxidation zone pH monitoring electrode; 12-Outer shell annular dosing device; 13-Acidification and reduction inlet; 14-Acidification and reduction dosing pipe; 15-pH adjustment dosing port; 16-Coagulation and crystallization zone pH monitoring electrode; 17-Coagulant dosing port; 18-Coagulation and crystallization zone stirring rod; 19-Water flow baffle; 20-Rotating shaft ; 21-Reactor outer shell; 22-Inner cavity; 23-Coagulation and crystallization zone; 24-Coagulation and crystallization settling zone; 25-Inclined tube sedimentation sludge settling zone; 26-Acidification and reduction zone; 27-Fenton fluidized oxidation zone; 28-Circulation reflux zone; 29-Submersible propeller pump; 30-Circulation reflux inlet; 31-Crystallization reflux channel; 32-Triangular guide plate; 33-Inclined tube sedimentation zone; 34-Water flow plate; 35-Inclined tube; 36-Effluent overflow collection weir; 37-Effluent pipe; 38-Agitator motor; 39-pH adjustment / coagulant / oxidant inlet. Detailed Implementation
[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0022] Please see the appendix Figure 1-3 The present invention provides a Fenton fluidized bed for the reuse of iron sludge, including a support 5, a reactor outer shell 21, an inner cavity 22, a stirring device, a wastewater jetting device 4, and an outlet pipe 37.
[0023] The support 5 is located at the bottom of the reactor outer shell 21 for support; the bottom of the reactor outer shell 21 is connected to the wastewater jet device 4; the inner cavity 22 is located inside the reactor outer shell 21 through a frame.
[0024] The inner cavity 22 is formed from bottom to top into a Fenton fluidized oxidation zone 27 and a coagulation crystallization zone 23; the gap between the inner cavity 22 and the outer shell 21 of the reactor is formed from top to bottom into a coagulation crystallization sedimentation zone 24, an acidification reduction zone 26 and a circulation reflux zone 28.
[0025] The bottom of the inner cavity 22 is connected to the wastewater jet device 4 through the return pipe 8. The wastewater jet device 4 is used to introduce wastewater and air into the inner cavity 22.
[0026] The wastewater jet device 4 includes a high-pressure water pump 3, an inlet pipe 1, an air inlet pipe 2, and a nozzle; the output end of the high-pressure water pump 3 is fixedly connected to one end of the nozzle via a flange; the nozzle is connected to the high-pressure water pump 3 via the inlet pipe 1 and the air inlet pipe 2; the nozzle includes a primary jet mixing zone 6 with a gradually increasing inner diameter and a secondary jet mixing zone 7 with a gradually decreasing inner diameter, and the primary jet mixing zone 6 and the secondary jet mixing zone 7 are fixedly connected via a flange; the secondary jet mixing zone 7 penetrates the reactor shell 21 and is connected to the return pipe 8.
[0027] The high-pressure water pump 3 generates a high-speed water flow, which creates a negative pressure around the nozzle to draw in air. After being fully mixed in the primary jet mixing zone 6 of the nozzle, the air and water flow are formed. Then, after being pressurized in the secondary jet mixing zone 7, the high-speed jet is injected into the return pipe 8.
[0028] Multiple crystallization reflux channels 31 are uniformly arranged on the side wall of the reflux pipe 8, connecting the interior of the reactor outer shell 21 and the bottom of the inner cavity 22, that is, connecting the circulation reflux zone 28 and the Fenton fluidized oxidation zone 27. The high-speed jet entering the reflux pipe 8 can create a negative pressure, driving the fluidized carrier and Fe through the crystallization reflux channels 31 back to the reactor. 2+ The solution is then returned to the Fenton fluidized oxidation zone 27 to begin the next purification cycle with the wastewater.
[0029] The Fenton fluidized oxidation zone 27 is filled with fluidizing carriers (ceramsite, quartz sand, activated carbon particles, etc.) and iron-rich solid waste from wastewater treatment (Fenton iron sludge, circuit board sludge, etc.). Wastewater enters the Fenton fluidized oxidation zone 27 through the wastewater jet device 4, and the oxidant is added by the self-dosing system. Under the stirring action of the agitator and the impact of the high-speed jet of wastewater, the fluidizing carriers, Fenton iron sludge, oxidant, and wastewater are thoroughly mixed.
[0030] The pH value of the mixed solution is monitored by pH monitoring electrode 11 in the oxidation zone. The solution pH is around 3.0. Fenton iron sludge and oxidant undergo a Fenton-like reaction to generate highly oxidizing free radicals that oxidize and degrade pollutants in the wastewater. Meanwhile, the fluidized carrier forms a fluidized state, which promotes mass transfer between the oxidant and the wastewater and promotes the crystallization of iron ions on the carrier surface, thus loading iron species (such as FeOx and FeOOH) onto its surface. After passing through the Fenton fluidized oxidation zone 27, the wastewater enters the coagulation and crystallization zone 23.
[0031] A water flow baffle 19 is provided at the top of the inner cavity 22; an inclined tube sedimentation sludge settling zone 25 is provided above the water flow baffle 19; and an inclined tube sedimentation zone 33 is provided above the inclined tube sedimentation sludge settling zone 25. The effluent pipe 37 is provided on one side of the top of the reactor outer shell 21, above the inclined tube sedimentation zone 33.
[0032] The water flow baffle 19 has an upward-pointing conical structure. The inner side is used to block the upward flow of the mixed flow in the coagulation and crystallization zone 23 and diffuses to the surrounding area, entering the interior of the reactor shell 21. Part of it flows downward into the coagulation and crystallization settling zone 24, and the other part flows upward into the inclined tube sedimentation sludge settling zone 25.
[0033] The inclined tube sedimentation zone 33 is provided with several inclined tubes 35. The bottom of the inclined tubes 35 is fixed inside the reactor shell 21 by a water-passing plate 34, and the top is fixed to the inner wall of the reactor shell 21 by an overflow collection weir 36.
[0034] Part of the water flowing through the inclined tube sedimentation sludge settling zone 25 passes through the inclined tube sedimentation zone 33, where it settles into larger flocs and slides down to the upper part of the water flow baffle 19. Under the action of gravity, it enters the coagulation and crystallization settling zone 24 and continues to settle downwards. Meanwhile, the clarified water continues to rise, and after passing through the overflow collection weir 36, it flows out through the outlet pipe 37.
[0035] The mixed flow entering the coagulation and crystallization settling zone 24 contains fluidizing carriers and large flocculent iron sludge. A mixture of acid and reducing agent is added via a dosing system, and the mixture, along with the flocculent iron sludge, enters the acidification and reduction zone 26. Under acidic conditions, the flocculent iron sludge dissolves Fe. 3+ Ions are reduced to Fe under the action of a reducing agent. 2+ The mixed flow continues to flow into the recirculation zone 28.
[0036] The bottom of the inner cavity 22 is arc-shaped, and the inner wall of the bottom of the reactor outer shell 21 is arc-shaped, so that the circulation reflux zone 28 enclosed by the bottom of the inner cavity 22 and the inner wall of the bottom of the reactor outer shell 21 forms an arc-shaped region; fluidized carrier and Fe 2+ The solution is guided by the arc-shaped circulating reflux zone 28 and enters the reflux tube 8 through the crystallization reflux channel 31 on the reflux tube 8. It is then carried by the high-speed jet back into the Fenton fluidized oxidation zone 27.
[0037] Preferably, the circulating reflux zone 28 is equipped with multiple sets of submersible propulsion pumps 29 to promote the fluidization of the carrier and Fe. 2+ The solution is returned to the reflux tube 8.
[0038] The outer wall of the reflux pipe 8 is provided with a plurality of uniformly arranged circulation reflux inlets 30 and triangular guide plates 32, which are spaced apart. The circulation reflux inlets 30 are connected to the crystallization reflux channel 31. The triangular guide plates 32 are used to guide the fluidized carrier and Fe refluxed in the circulation reflux zone. 2+ The solution enters the circulation reflux inlet 30.
[0039] The lower end of the stirring device penetrates the inclined tube sedimentation zone 33 and the water flow baffle 19, and is disposed in the inner cavity 22. The stirring device includes a stirring motor 38, a rotating shaft 20, two sets of stirring rods 18 for the coagulation and crystallization zone, and multiple sets of stirring rods 10 for the oxidation zone. The stirring motor 38 is fixedly installed on the top of the reactor outer shell 21. The upper end of the rotating shaft 20 penetrates the reactor outer shell 21 and is fixedly connected to the output shaft of the stirring motor 38, and the lower end is disposed inside the inner cavity 22. The two sets of stirring rods 18 for the coagulation and crystallization zone are installed on the rotating shaft 20 and are located in the middle of the inner cavity 22. The multiple sets of stirring rods 10 for the oxidation zone are installed on the rotating shaft 20 and are located at the bottom of the inner cavity 22.
[0040] A pH monitoring electrode 11 for the oxidation zone is installed on the rotating shaft 20 inside the Fenton fluidized oxidation zone 27 to monitor the pH value in the Fenton fluidized oxidation zone 27; a pH monitoring electrode 16 for the coagulation and crystallization zone is installed on the rotating shaft 20 inside the coagulation and crystallization zone 23 to monitor the pH value in the coagulation and crystallization zone 23.
[0041] The fluidized bed of the present invention also includes a dosing system, which includes a pH adjustment / coagulant / oxidant inlet 39, a coagulant dosing inlet 17, a pH adjustment dosing inlet 15, an oxidant dosing inlet 9, and an outer ring dosing device 12.
[0042] The rotating shaft 20 is hollow, with a pH adjustment / coagulant / oxidant inlet 39 at the top and a coagulant dosing inlet 17, a pH adjustment dosing inlet 15, and an oxidant dosing inlet 9 at the bottom.
[0043] Multiple sets of coagulant dosing ports 17 are evenly arranged along a set of stirring rods 18 in the coagulation and crystallization zone 23, for adding coagulant to the coagulation and crystallization zone 23. Multiple sets of pH adjustment dosing ports 15 are located below the coagulant dosing ports 17 and are evenly arranged along another set of stirring rods 18 in the coagulation and crystallization zone 23, for adding alkaline solution to the coagulation and crystallization zone 23. Oxidant dosing ports 9 are located at the bottom of the rotating shaft 20, for adding oxidants such as hydrogen peroxide, persulfate, peracetic acid, percarbonate, calcium peroxide, periodate, etc., to the Fenton fluidized oxidation zone 27. The annular dosing device 12 is fixedly sleeved in the middle of the reactor shell 21, and an acidification and reduction inlet 13 is provided on the outer side. Multiple sets of acidification and reduction dosing pipes 14 are evenly arranged circumferentially on the inner side of the annular dosing device 12, which penetrate through the side wall of the reactor shell 21 and extend into the interior of the reactor shell 21. They are used to pass a mixture of acid (such as sulfuric acid) and reducing agent (such as sodium thiosulfate, sodium metabisulfite, hydroxylamine hydrochloride, etc.) into the mixed flow path.
[0044] In operation, wastewater, after passing through a high-pressure water pump and a wastewater jet device 4, enters the Fenton fluidized oxidation zone 27 via a return pipe 8. The Fenton fluidized oxidation zone 27 is filled with a fluidizing carrier and Fenton iron sludge. The oxidant enters through an oxidant dosing port 9 located within the Fenton fluidized oxidation zone 27. Under the stirring action of the agitator and the impact of the high-speed wastewater jet, the fluidizing carrier, Fenton iron sludge, oxidant, and wastewater are thoroughly mixed. The Fenton iron sludge and oxidant undergo a Fenton-like reaction to generate highly oxidizing free radicals that oxidize and degrade pollutants in the wastewater. Meanwhile, the fluidizing carrier forms a fluidized state, promoting mass transfer between the oxidant and wastewater while simultaneously causing iron ions to crystallize on the carrier surface, forming a catalytic carrier with surface-loaded iron species (such as FeOx and FeOOH). Through dynamic circulation in the fluidized bed, Fe²⁺ is achieved. + The continuous release of [something] improves the efficiency of wastewater treatment.
[0045] After passing through the Fenton fluidized oxidation zone 27, the wastewater enters the coagulation and crystallization zone 23. The alkaline solution enters through the pH adjustment dosing port 15 installed on the stirring rod 18 in the coagulation and crystallization zone to adjust the pH value of the solution to neutral. Then, the coagulant enters through the coagulant dosing port 17 on the stirring rod 18 in the coagulation and crystallization zone. Under the action of the stirring rod 18 in the coagulation and crystallization zone, it is rapidly mixed with the reaction solution, triggering the coagulation and crystallization reaction. More iron species crystallize and precipitate on the surface of the fluidized carrier, forming a catalytic carrier with iron species loading. At the same time, iron ions in the reaction solution precipitate and form flocculent iron sludge under the action of compressed double electric layer.
[0046] Wastewater, fluidized carrier, and flocculent iron sludge flow upwards and encounter an inclined baffle 19, causing their flow direction to change, and they enter the coagulation and crystallization settling zone 24. The wastewater and smaller flocculent iron sludge rise into the inclined tube sedimentation zone 33, where the flocculent iron sludge settles into larger flocs and slides down to the upper part of the baffle 19. Under gravity, it enters the coagulation and crystallization settling zone 24 and settles downwards. Meanwhile, the clarified water, separated from the flocculent iron sludge in the inclined tube sedimentation zone 33, continues to rise, passing through the overflow collection weir 36 and flowing out through the outlet pipe 37. The fluidized carrier and larger flocculent iron sludge settle downwards under gravity, and during this descent, the flocculent iron sludge undergoes bridging, adsorption, and trapping processes, further agglomerating into even larger flocs and settling rapidly.
[0047] An annular dosing device 12 located in the middle of the reactor shell 21 introduces a mixture of acid and reducing agent into the reactor shell 21 through an acidification-reduction dosing pipe. After the acidification-reduction dosing, the flocculent iron sludge enters the acidification-reduction zone, where it dissolves Fe under acidic conditions. 3+ Ions are reduced to Fe under the action of a reducing agent. 2+ Subsequently, the fluidized carrier and the Fe formed after acidification and reduction 2+The solution enters the arc-shaped reflux zone 28, where, driven by a submersible pump, the fluidized carrier and the Fe formed after acidification and reduction... 2+ The solution is guided by the triangular guide plate 32 and quickly enters the Fenton fluidized oxidation zone 27 from the upwardly inclined crystallization reflux channel 31, starting the next cycle of reaction.
[0048] This fluidized bed integrates oxidation, coagulation and crystallization, mud-water separation, iron sludge and fluidized carrier recycling into one device. It has a small footprint, good treatment effect, and achieves resource recycling, which has a good effect on cost reduction and efficiency improvement.
[0049] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.
[0050] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A Fenton fluidized bed for the reuse of iron sludge, characterized in that, The reactor includes a support (5), a reactor outer shell (21), an inner cavity (22), a stirring device, a wastewater jet device (4), an outlet pipe (37), and a dosing system. The support (5) is located at the bottom of the reactor outer shell (21). The bottom of the reactor outer shell (21) is connected to the wastewater jet device (4). The inner cavity (22) is located inside the reactor outer shell (21) via a frame. The bottom of the inner cavity (22) is connected to the wastewater jet device (4) via a return pipe (8). The wastewater jet device (4) is used to introduce wastewater and air into the inner cavity (22). The lower end of the stirring device is located in the inner cavity (22). The dosing system is used to inject chemicals into the inner cavity (22) and the reactor outer shell (21). The outlet pipe (37) is located on one side of the top of the reactor outer shell (21). The inner cavity (22) is formed from bottom to top into a Fenton fluidized oxidation zone (27) and a coagulation crystallization zone (23); the gap between the inner cavity (22) and the reactor outer shell (21) is formed from top to bottom into a coagulation crystallization sedimentation zone (24), an acidification reduction zone (26), and a circulation reflux zone (28); a plurality of crystallization reflux channels (31) are uniformly arranged on the side wall of the reflux pipe (8), connecting the inside of the reactor outer shell (21) and the bottom of the inner cavity (22); The Fenton fluidized oxidation zone (27) is filled with fluidized carriers and iron-rich wastewater treatment solid waste.
2. The Fenton fluidized bed for reusing iron sludge according to claim 1, characterized in that, The wastewater jet device (4) includes a high-pressure water pump (3), an inlet pipe (1), an air inlet pipe (2), and a nozzle; the output end of the high-pressure water pump (3) is fixedly connected to one end of the nozzle via a flange; the nozzle is connected to the high-pressure water pump (3) via an inlet pipe (1) and an air inlet pipe (2); the nozzle includes a primary jet mixing zone (6) with a gradually increasing inner diameter and a secondary jet mixing zone (7) with a gradually decreasing inner diameter, and the primary jet mixing zone (6) and the secondary jet mixing zone (7) are fixedly connected via a flange; the secondary jet mixing zone (7) penetrates the reactor shell (21) and is connected to the return pipe (8).
3. The Fenton fluidized bed for reusing iron sludge according to claim 1, characterized in that, The inner cavity (22) is provided with a water flow baffle (19) with a pointed tip forming a cone shape at the top; an inclined tube sedimentation sludge settling zone (25) is provided above the water flow baffle (19); an inclined tube sedimentation zone (33) is provided above the inclined tube sedimentation sludge settling zone (25); the water flow baffle (19) is used to block the upward flow of the mixed flow in the coagulation and crystallization zone (23), part of which flows downward into the coagulation and crystallization settling zone (24), and the other part flows upward into the inclined tube sedimentation sludge settling zone (25).
4. The Fenton fluidized bed for iron sludge reuse according to claim 3, characterized in that, The inclined tube sedimentation zone (33) is provided with several inclined tubes (35) arranged at an angle. The bottom of the inclined tubes (35) is fixed inside the reactor shell (21) through a water-passing plate (34), and the top is fixed to the inner wall of the reactor shell (21) through an overflow collection weir (36).
5. The Fenton fluidized bed for reusing iron sludge according to claim 1, characterized in that, The bottom of the inner cavity (22) is set to be arc-shaped, and the bottom inner wall of the reactor outer shell (21) is set to be arc-shaped, so that the circulation reflux zone (28) enclosed by the bottom of the inner cavity (22) and the bottom inner wall of the reactor outer shell (21) forms an arc-shaped area.
6. The Fenton fluidized bed for iron sludge reuse according to claim 5, characterized in that, Multiple submersible thrust pumps (29) are installed in the circulating reflux zone (28).
7. The Fenton fluidized bed for reusing iron sludge according to claim 2, characterized in that, The outer wall of the reflux pipe (8) is provided with a plurality of circulating reflux inlets (30) and triangular guide plates (32) evenly arranged. The circulating reflux inlets (30) and triangular guide plates (32) are arranged at intervals. The circulating reflux inlets (30) are connected to the crystallization reflux channel (31).
8. The Fenton fluidized bed for reusing iron sludge according to claim 1, characterized in that, The stirring device includes a stirring motor (38), a rotating shaft (20), two sets of stirring rods (18) for the coagulation and crystallization zone, and multiple sets of stirring rods (10) for the oxidation zone. The stirring motor (38) is fixedly installed on the top of the reactor shell (21). The upper end of the rotating shaft (20) passes through the reactor shell (21) and is fixedly connected to the output shaft of the stirring motor (38). The lower end is located inside the inner cavity (22). The two sets of stirring rods (18) for the coagulation and crystallization zone are installed on the rotating shaft (20) and are located in the middle of the inner cavity (22). The multiple sets of stirring rods (10) for the oxidation zone are installed on the rotating shaft (20) and are located at the bottom of the inner cavity (22).
9. The Fenton fluidized bed for iron sludge reuse according to claim 8, characterized in that, A pH monitoring electrode (11) for monitoring the pH value in the Fenton fluidized oxidation zone (27) is installed on the rotating shaft (20); a pH monitoring electrode (16) for monitoring the pH value in the coagulation crystallization zone (23) is installed on the rotating shaft (20).
10. The Fenton fluidized bed for reusing iron sludge according to claim 8, characterized in that, The dosing system includes a pH adjustment / coagulant / oxidant inlet (39), a coagulant dosing inlet (17), a pH adjustment dosing inlet (15), an oxidant dosing inlet (9), and a ring-shaped dosing device (12) in the outer shell; the rotating shaft (20) is hollow, with a pH adjustment / coagulant / oxidant inlet (39) at the top and the coagulant dosing inlet (17), pH adjustment dosing inlet (15), and oxidant dosing inlet (9) at the bottom; the coagulant dosing inlet (17) is evenly arranged in multiple sets along a set of stirring rods (18) in the coagulation crystallization zone. The pH adjustment dosing port (15) is located below the coagulant dosing port (17), and multiple sets are evenly arranged along the stirring rod (18) of another set of coagulation crystallization zone; the oxidant dosing port (9) is located at the bottom end of the rotating shaft (20); the outer ring dosing device (12) is fixedly sleeved in the middle of the reactor outer shell (21), with an acidification and reduction inlet (13) on the outside and multiple sets of acidification and reduction dosing pipes (14) evenly arranged on the inner circumference, penetrating the side wall of the reactor outer shell (21) and extending into the interior of the reactor outer shell (21).