CN114853266A

CN114853266A - Intelligent integrated sewage treatment device of Jiugong pond

Info

Publication number: CN114853266A
Application number: CN202210424011.7A
Authority: CN
Inventors: 李春放; 刘宏华; 刘军
Original assignee: Changzhou Kede Water Treatment Complete Equipment Co ltd
Current assignee: Changzhou Kede Water Treatment Complete Equipment Co ltd
Priority date: 2022-04-21
Filing date: 2022-04-21
Publication date: 2022-08-05
Anticipated expiration: 2042-04-21
Also published as: CN114853266B

Abstract

The invention discloses a nine-palace pond intelligent integrated sewage disposal device, which comprises a sewage treatment station, wherein nine groups of oxidation ponds are arranged in the middle of the sewage treatment station, the nine groups of oxidation ponds are arranged in a nine-palace mode and are connected in series end to end through a pipeline, a foundation is arranged below the sewage treatment station, an adjusting pond and a sludge pond are arranged on the left side of the foundation, an outlet of the adjusting pond is connected with an oxidation pond pipeline, a valve cavity is arranged in the pipeline, a sewage pipe and a clean water pipe are arranged at the left end of the adjusting pond, the sewage pipe is connected with a waste water discharge port pipeline, the clean water pipe is connected with an external water source pipeline, a clean water pump is arranged in the pipeline, a filter plate is arranged in the adjusting pond, a plurality of groups of filter holes are arranged on the surface of the filter plate, a fixed shaft is fixed at the front end of the adjusting pond, and a disc is connected to a rear end bearing of the fixed shaft, so that the intelligent mixing and automatic dredging functions are conveniently realized, the requirements of energy conservation and environmental protection are met.

Description

Intelligent integrated sewage treatment device of Jiugong pond

Technical Field

The invention is applied to the background of sewage treatment equipment and is named as an intelligent integrated sewage treatment device of a Jiugong pond.

Background

The sewage treatment device is a device for treating domestic sewage and industrial sewage, the sewage treatment process is actually a process for enabling the sewage to reach the water quality requirement of being discharged into a certain water body or being reused to purify the sewage, and the sewage treatment device is widely applied to various fields of buildings, agriculture, traffic, energy sources, petrifaction, environmental protection, urban landscape, medical treatment, catering and the like, and is also increasingly used in daily life of common people.

However, the existing sewage treatment device comprises an adjusting tank and a sludge tank, sewage needs to be pretreated and precipitated by silt, too many large particles are prevented from entering an oxidation pond, the discharge flow of the sewage is unstable, and the existing equipment cannot timely mix clear water according to the flow, so that the concentration of the treated sewage is consistent, and when the sewage is injected into the oxidation pond, a filter screen is easy to block, and the existing equipment is manually cleaned, thereby wasting time and energy.

Therefore, it is necessary to provide an intelligent integrated sewage treatment device for the Jiugong pond, which can achieve the functions of intelligent mixing and automatic blockage dredging.

Disclosure of Invention

The invention aims to provide an intelligent integrated sewage treatment device of a Jiugong pond to solve the problems in the background technology.

In order to solve the technical problems, the invention provides the following technical scheme: the intelligent integrated form sewage treatment plant in nine palace ponds contains the sewage treatment station, the centre at sewage treatment station is provided with nine oxidation ponds of group, nine groups the oxidation pond is arranged and end to end through the pipeline with nine palace forms and is established ties, the below at sewage treatment station is provided with the ground, the left side of ground is provided with equalizing basin and sludge impoundment, the export and the oxidation pond pipe connection of equalizing basin, and be provided with the valve pocket in the pipeline, the left end of equalizing basin is provided with sewage pipe and clean water pipe, sewage pipe and wastewater discharge port pipe connection, clean water pipe and outside water source pipe connection and in the pipeline are provided with clean water pump, the inside of equalizing basin is provided with the filter plate, the surface of filter plate is provided with the multiunit filtration pore.

In one embodiment, the front end of equalizing basin is fixed with the dead axle, the rear end bearing of dead axle is connected with the disc, be fixed with multiunit blade around the disc, the blade is located the sewage pipe under, the one end of blade is provided with the waste liquid groove, the other end of blade is provided with the water hole, dead axle cavity and port are provided with the breach, the inside cavity and the export that are provided with of blade are just to the breach, the dead axle passes through cavity and sludge impoundment pipe connection, and is provided with the sludge pump in the pipeline.

In one embodiment, the inside of disc is provided with the multiunit sap cavity, and the multiunit the nearly axle head in sap cavity all is fixed with the pressure spring, the other end of pressure spring is fixed with the piston, piston and sap cavity sliding connection, the clarified water pump is established ties there is the resistance, the inside of resistance is provided with the slide rail, the one end of resistance is fixed with the support, the right-hand member of support is fixed with the elasticity bag, the right-hand member of elasticity bag is fixed with the insulator, the right-hand member of insulator is fixed with the gleitbretter, gleitbretter and slide rail sliding connection, the axle head far away of sap cavity passes through rotatory subassembly pipe connection with the elasticity bag.

In one embodiment, the rotating assembly comprises a rotating cavity, one end of the rotating cavity is in bearing connection with a fixed cavity, the rotating cavity is connected with a liquid cavity pipeline, and the fixed cavity is connected with an elastic bag pipeline.

In one embodiment, a detection cavity is fixed at the bottom of the regulating tank, an elastic pull rope is fixed at the bottom of the inner side of the detection cavity, a movable block is fixed at the other end of the elastic pull rope, a pull rope is fixed at the upper end of the movable block, a floating body is fixed at the other end of the pull rope, an elastic rope is fixed at the bottom of the inner side of the valve cavity, a valve block is fixed at the other end of the elastic rope, and the detection cavity is connected with a valve cavity pipeline.

In one embodiment, a motor is fixed at the rear end of the regulating tank, a rotating shaft is fixed at the output end of the motor, the rotating shaft extends into the disc, a plurality of groups of extension springs are fixed at the front end of the rotating shaft, a bump is fixed at the other end of each of the extension springs, a groove is formed in the inner side of the disc, an electric box is fixed at the upper end of the detection cavity, a switch is fixed in the electric box, a through hole is formed in the upper end of the detection cavity, the switch penetrates through the through hole, a spring is arranged in the through hole, the switch is located right above the floating body, and the switch is connected with the motor in series.

In one embodiment, the outer end of the blade is provided with a cleaning cavity, the outer side of the cleaning cavity is provided with a hole, the inside of the cleaning cavity is fixed with a tension spring, and the other end of the tension spring is fixed with a cleaning block.

In one embodiment, portions of the oxidation basin are disposed underground.

In one embodiment, the oxidation basin is made of stainless steel.

Compared with the prior art, the invention has the following beneficial effects: the invention has the advantages that the adjusting tank and the sludge tank are arranged, the separation of sludge and water is conveniently realized, the injection amount of clear water can be adjusted in real time according to the injected sewage amount, the concentration of sewage is kept at a lower level, the pollution and the damage to sewage purification equipment are avoided, and meanwhile, when the sewage output is blocked, the filter plate can be automatically driven by switching electric drive to vibrate at high speed, so that the smoothness of the sewage input and output is ensured.

Drawings

The technical solution and other advantages of the present application will become apparent from the detailed description of the embodiments of the present application with reference to the accompanying drawings.

In the drawings:

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a schematic top view of the overall structure of the present invention;

FIG. 3 is a schematic cross-sectional view of the overall structure of the present invention;

FIG. 4 is a schematic view of the construction of a conditioning tank of the present invention;

FIG. 5 is a schematic view of the partial structure at A of the present invention;

FIG. 6 is a schematic view of a disk configuration of the present invention;

FIG. 7 is a schematic view of the sludge flow line of the present invention;

FIG. 8 is a schematic diagram of a variable resistor structure according to the present invention;

FIG. 9 is a schematic view of the construction of the rotating assembly of the present invention;

FIG. 10 is a schematic view of the partial structure of the present invention at B;

FIG. 11 is a schematic view of the liquid level detection and flow control principle of the present invention;

in the figure: 1. a sewage treatment station; 2. a foundation; 3. an oxidation pond; 4. a regulating tank; 5. a sludge tank; 6. a sewage pipe; 7. a clear water pipe; 8. a clean water pump; 9. a sludge pump; 10. a valve cavity; 11. a motor; 12. filtering the plate; 13. a rotating shaft; 14. fixing a shaft; 15. a disc; 16. a blade; 17. a water pore; 18. a waste liquid tank; 19. a piston; 20. a pressure spring; 21. a liquid chamber; 22. a hole; 23. a cleaning block; 24. a tension spring; 25. a detection chamber; 26. an elastic pull rope; 27. pulling a rope; 28. a float; 29. sliding blades; 30. an insulator; 31. a support; 32. a resistance; 33. an elastic bag; 34. a fixed cavity; 35. a rotating chamber; 36. an elastic cord; 37. a valve block; 38. an electric box; 39. a spring; 40. a switch; 41. a through hole; 43. a notch; 44. an extension spring; 45. a bump; 46. a groove; 47. a slide rail; 48. a movable block; 49. the chamber is cleaned.

Detailed Description

The following disclosure provides many different embodiments or examples for implementing different features of the application. In order to simplify the disclosure of the present application, specific example components and arrangements are described below. Of course, they are merely examples and are not intended to limit the present application. Moreover, the present application may repeat reference numerals and/or letters in the various examples, such repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. In addition, examples of various specific processes and materials are provided herein, but one of ordinary skill in the art may recognize applications of other processes and/or use of other materials.

Referring to fig. 1-4, the present invention provides the following technical solutions: nine-palace pond intelligent integrated sewage treatment device comprises a sewage treatment station 1, nine groups of oxidation ponds 3 are arranged in the middle of the sewage treatment station 1, the nine groups of oxidation ponds 3 are arranged in a nine-palace mode and are connected in series end to end through pipelines, the oxidation ponds 3 are nine groups or more than nine groups, one group or more than nine groups are arranged in a nine-palace mode or are arranged in a straight line mode or other modes and are arranged on the ground or semi-ground, process optimization can be performed to the maximum due to a multi-pond series mode, for example, a water treatment process of hydrolysis and facultative is arranged at the front end, the middle stage and the rear stage mainly adopt aerobic, a foundation 2 is arranged below the sewage treatment station 1, an adjusting pond 4 and a sludge pond 5 are arranged on the left side of the foundation 2, an outlet of the adjusting pond 4 is connected with the oxidation pond 3 through a pipeline, a valve cavity 10 is arranged in the pipeline, a sewage pipe 6 and a clean water pipe 7 are arranged at the left end of the adjusting pond 4, the sewage pipe 6 is connected with a waste water discharge port through a pipeline, the clean water pipe 7 is connected with an external water source pipeline, a clean water pump 8 is arranged in the pipeline, the adjusting tank 4 can carry out pretreatment and sludge separation on sewage through the injection of the sewage and clean water, so that the water quality input into the oxidation tank 3 is uniform, the inconvenience of treatment due to overlarge sewage concentration is prevented, a filter plate 12 is arranged in the adjusting tank 4, a plurality of groups of filter holes are formed in the surface of the filter plate 12, and overlarge floccules and sludge in the sewage can be blocked through the arrangement of the filter plate 12, so that the sewage purification efficiency is improved, and the purification equipment is protected;

referring to fig. 4, 5 and 7, a fixed shaft 14 is fixed at the front end of the adjusting tank 4, a disc 15 is connected to the rear end bearing of the fixed shaft 14, the disc 15 can move circularly around the fixed shaft 14, a plurality of sets of blades 16 are fixed around the disc 15, the blades 16 are positioned under the sewage pipe 6, a waste liquid tank 18 is arranged at one end of each blade 16, a water hole 17 is arranged at the other end of each blade 16, the fixed shaft 14 is hollow, a notch 43 is arranged at the port of the fixed shaft 14, a cavity is arranged inside each blade 16, the outlet of each blade is opposite to the notch 43, the notch 43 is positioned between the end of the fixed shaft 14 and the bearing and is provided with a plurality of sets of connecting ribs, the fixed shaft 14 is connected with the sludge tank 5 through the hollow pipeline, and a sludge pump 9 is arranged in the pipeline, because the blades 16 are positioned under the sewage pipe 6, when sewage is injected from the sewage pipe 6, the blades 16 can be driven to rotate to stir the sewage, so as to prevent sludge from sinking, meanwhile, the waste liquid tank 18 can automatically shovel sludge in the sewage into the blades 16, and the sludge falls into the gap 43 through the cavity in the blades 16 under the action of the sludge pump 9, and then enters the sludge tank from the hollow part of the fixed shaft 14 through a pipeline;

referring to fig. 6 and 8, a plurality of sets of liquid chambers 21 are arranged inside a disc 15, a pressure spring 20 is fixed at a proximal shaft end of each of the plurality of sets of liquid chambers 21, a piston 19 is fixed at the other end of the pressure spring 20, the piston 19 is slidably connected with the liquid chamber 21, hydraulic oil is arranged in each of the liquid chambers 21, when the disc 15 rotates counterclockwise, the piston 19 moves towards a distal shaft end due to centrifugal force, so as to extrude the hydraulic oil in the liquid chamber 21, a resistor 32 is connected in series with a clean water pump 8, a slide rail 47 is arranged inside the resistor 32, a support 31 is fixed at one end of the resistor 32, an elastic bag 33 is fixed at the right end of the support 31, an insulator 30 is fixed at the right end of the elastic bag 33, a slide sheet 29 is fixed at the right end of the insulator 30, the slide sheet 29 is slidably connected with the slide rail 47, the resistor 32 is similar to a slide rheostat and is hydraulic controlled, hydraulic oil is arranged in the elastic bag 33, and when the elastic bag 33 expands, the slide sheet 29 is pushed to move rightwards, thereby reducing the resistance in the circuit of the clean water pump 8, increasing the power of the clean water pump 8, increasing the amount of the pumped clean water, driving the slide sheet 29 to move leftwards when the elastic bag 33 contracts, thereby increasing the resistance in the circuit of the clean water pump 8, reducing the power of the clean water pump 8, reducing the pumped clean water, connecting the far shaft end of the liquid cavity 21 with the elastic bag 33 through a rotating component pipeline, when no sewage is injected, the elastic bag 33 is contracted to the minimum, the pumped clear water is the minimum, only the adjusting tank 4 is cleaned, the disc 15 is driven to rotate anticlockwise along with the injection of the sewage, thereby pressing the hydraulic oil in the hydraulic chamber 21 into the elastic bag 33 to expand it, and the more the sewage is injected, the larger the expansion amplitude of the elastic bag 33, therefore, the more clear water is pumped, the purpose of pumping clear water according to the flow of sewage is achieved, and the effect of adjusting the water quality and keeping the concentration of the clear water consistent is achieved;

referring to fig. 9, the rotating assembly includes a rotating cavity 35, one end of the rotating cavity 35 is connected with a fixed cavity 34 through a bearing, the rotating cavity 35 is connected with the liquid cavity 21 through a pipeline, the fixed cavity 34 is connected with the elastic bag 33 through a pipeline, because the rotation of the disc 15 can wind the hydraulic pipeline, and the stability of hydraulic transmission is ensured by the arrangement of the rotating cavity 35;

referring to fig. 11, a detection chamber 25 is fixed at the bottom of the regulation tank 4, an elastic pull rope 26 is fixed at the bottom of the inner side of the detection chamber 25, a movable block 48 is fixed at the other end of the elastic pull rope 26, a pull rope 27 is fixed at the upper end of the movable block 48, a floating body 28 is fixed at the other end of the pull rope 27, an elastic rope 36 is fixed at the bottom of the inner side of the valve chamber 10, a valve block 37 is fixed at the other end of the elastic rope 36, the detection chamber 25 is connected with the valve chamber 10 through a pipeline, hydraulic oil is disposed in the detection chamber 25 and the valve chamber 10, the floating body 28 acts on the movable block 48 by its own gravity in an initial state, and presses the hydraulic oil in the detection chamber 25 into the valve chamber 10 to push the valve block 37 to completely seal the liquid outlet pipeline, the pull rope is short and elastic, and at the same time, when the buoyancy reaches the maximum, the water outlet flow of the sewage discharge pipeline is greater than the maximum water injection flow, and the sewage in the regulation tank 4 increases, until the floating body 28 is subjected to buoyancy, the force of the floating body 28 extruding the detection cavity 25 is reduced, hydraulic oil in the valve cavity 10 slowly enters the detection cavity 25 under the action of the spring force, so that a liquid outlet pipeline is opened and sewage is provided for the oxidation tank 3, the opening amplitude of the valve block 37 is increased along with the increase of the sewage in the adjusting tank 4 until a balance point is reached, the amount of the injected sewage and the clear water is the same as the amount of the discharged sewage, and the water level in the adjusting tank 4 is not increased at this time, so that the purpose of controlling the water level in the adjusting tank 4 is achieved;

referring to fig. 6 and 11, a motor 11 is fixed at the rear end of the adjusting tank 4, a rotating shaft 13 is fixed at the output end of the motor 11, the rotating shaft 13 extends into the disc 15, a plurality of sets of extension springs 44 are fixed at the front end of the rotating shaft 13, bumps 45 are fixed at the other ends of the sets of extension springs 44, a groove 46 is arranged on the inner side of the disc 15, an electric box 38 is fixed at the upper end of the detection cavity 25, a switch 40 is fixed inside the electric box 38, a through hole 41 is arranged at the upper end of the detection cavity 25, the switch 40 penetrates through the through hole 41, a spring 39 is arranged in the through hole 41, the switch 40 is positioned right above the floating body 28, the switch 40 is connected in series with the motor 11, as the sewage treatment continues, more and more floccules and more sludge are accumulated in the adjusting tank 4, so as to block the filter plate 12, at this time, the opening speed of the valve block 37 cannot discharge the sewage in the adjusting tank 4 in time, so that the water level rises constantly, along with the continuous rising of the water level, when the floating body 28 props against the switch 40 to close the switch, the motor 11 starts to work, so that the rotating shaft 13 is driven to move anticlockwise at a high speed, the rotating shaft 13 rotates at a high speed, the lug 45 is driven to move towards the far shaft end and is clamped in the groove 46, so that the disc 15 is driven to move anticlockwise at a high speed, and excessive floccules and sludge in the regulating tank 4 are discharged into the sludge tank 5 through the waste liquid tank 18, so that the automatic cleaning effect is achieved;

referring to fig. 6, the outer end of the blade 16 is provided with a cleaning cavity 49, the outer side of the cleaning cavity 49 is provided with a hole 22, the interior of the cleaning cavity 49 is fixed with a tension spring 24, the other end of the tension spring 24 is fixed with a cleaning block 23, the blade 16 is driven to move together at a high speed along with the high-speed movement of the disc 15, the cleaning block 23 slides out of the cleaning cavity 49 due to the action of centrifugal force, so that the rotating radius of the blade 16 is increased, the blade 12 can be flapped on the filter plate 12, and the filter plate 12 is continuously vibrated, so that floccules and sludge blocked on the filter plate 12 are discharged until the filter plate 12 is unblocked;

the oxidation ponds 3 are partially arranged underground, and the oxidation ponds 3 can be arranged on the ground or partially arranged underground according to conditions, so that the space is saved;

the oxidation pond 3 is stainless steel, and stainless steel both can increase corrosion resisting property, can reuse at this material simultaneously, environmental protection and saving.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; may be mechanically connected, may be electrically connected or may be in communication with each other; may be directly connected, may be internal to the two elements or may be in an interactive relationship with the two elements. The above terms are understood in the present application by those of ordinary skill in the art as appropriate.

The above detailed description is provided for a cleaning device provided in the embodiments of the present application, and the principle and the implementation of the present application are explained in the present application by applying specific examples, and the description of the above embodiments is only used to help understanding the technical solution and the core idea of the present application; those of ordinary skill in the art will understand that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications or substitutions do not depart from the spirit and scope of the present disclosure as defined by the appended claims.

Claims

1. Nine palace ponds intellectuality integrated form sewage treatment plant contains sewage treatment station (1), its characterized in that: the middle of sewage treatment station (1) is provided with nine oxidation ponds (3), nine groups oxidation pond (3) are arranged and end to end through the pipeline and are established ties with nine palace forms, the below of sewage treatment station (1) is provided with ground (2), the left side of ground (2) is provided with equalizing basin (4) and sludge impoundment (5), the export and the oxidation pond (3) pipe connection of equalizing basin (4), and be provided with valve pocket (10) in the pipeline, the left end of equalizing basin (4) is provided with sewage pipe (6) and clean water pipe (7), sewage pipe (6) and wastewater discharge port pipe connection, clean water pipe (7) and outside water source pipe connection and intraductal be provided with clean water pump (8), the inside of equalizing basin (4) is provided with filter plate (12), the surface of filter plate (12) is provided with the multiunit filtration pore.

2. The intelligent integrated sewage treatment device of nine-palace pond of claim 1, wherein: the front end of equalizing basin (4) is fixed with dead axle (14), the rear end bearing of dead axle (14) is connected with disc (15), be fixed with multiunit blade (16) around disc (15), blade (16) are located sewage pipe (6) under, the one end of blade (16) is provided with waste liquid groove (18), the other end of blade (16) is provided with water hole (17), dead axle (14) cavity and port are provided with breach (43), blade (16) inside is provided with the cavity and exports just to breach (43), dead axle (14) are through cavity and sludge impoundment (5) pipe connection, and are provided with sludge pump (9) in the pipeline.

3. The intelligent integrated sewage treatment device of nine-palace pond of claim 2, characterized in that: the inside of disc (15) is provided with multiunit sap cavity (21), multiunit the nearly axle head in sap cavity (21) all is fixed with pressure spring (20), the other end of pressure spring (20) is fixed with piston (19), piston (19) and sap cavity (21) sliding connection, clarified water pump (8) are established ties and are had resistance (32), the inside of resistance (32) is provided with slide rail (47), the one end of resistance (32) is fixed with support (31), the right-hand member of support (31) is fixed with elasticity bag (33), the right-hand member of elasticity bag (33) is fixed with insulator (30), the right-hand member of insulator (30) is fixed with gleitbretter (29), gleitbretter (29) and slide rail (47) sliding connection, the axle head of far away of sap cavity (21) is through rotatory subassembly pipe connection with elasticity bag (33).

4. The intelligent integrated sewage treatment device of nine-palace pond of claim 3, wherein: the rotating assembly comprises a rotating cavity (35), one end of the rotating cavity (35) is in bearing connection with a fixed cavity (34), the rotating cavity (35) is in pipeline connection with the liquid cavity (21), and the fixed cavity (34) is in pipeline connection with the elastic bag (33).

5. The intelligent integrated sewage treatment device of nine-palace pond of claim 4, wherein: the bottom of equalizing basin (4) is fixed with detects chamber (25), the inboard bottom that detects chamber (25) is fixed with elasticity stay cord (26), the other end of elasticity stay cord (26) is fixed with movable block (48), the upper end of movable block (48) is fixed with stay cord (27), the other end of stay cord (27) is fixed with body (28), the inboard bottom of valve pocket (10) is fixed with elasticity rope (36), the other end of elasticity rope (36) is fixed with valve block (37), detect chamber (25) and valve pocket (10) pipe connection.

6. The intelligent integrated sewage treatment device of nine-palace pond of claim 5, wherein: the rear end of equalizing basin (4) is fixed with motor (11), the output of motor (11) is fixed with pivot (13), pivot (13) stretch into the inside of disc (15), the front end of pivot (13) is fixed with multiunit extension spring (44), the multiunit the other end of extension spring (44) all is fixed with lug (45), the inboard of disc (15) is provided with recess (46), the upper end of detecting chamber (25) is fixed with electronic box (38), the inside of electronic box (38) is fixed with switch (40), the upper end of detecting chamber (25) is provided with through-hole (41), switch (40) run through-hole (41), and be provided with spring (39) in through-hole (41), switch (40) are located body (28) directly over, switch (40) and motor (11) are established ties.

7. The intelligent integrated sewage treatment device of nine-palace pond of claim 6, wherein: the outer end of blade (16) is provided with clean chamber (49), the outside in clean chamber (49) is provided with hole (22), the inside in clean chamber (49) is fixed with extension spring (24), the other end of extension spring (24) is fixed with clean piece (23).

8. The intelligent integrated sewage treatment device of nine-palace pond of claim 7, wherein: the parts of the oxidation pond (3) are arranged underground.

9. The intelligent integrated sewage treatment device of nine-palace pond of claim 8, wherein: the oxidation pond (3) is made of stainless steel.