Catalytic oxidation wastewater treatment device based on sludge-based biochar catalyst

Abstract

The utility model belongs to the technical field of organic polluted wastewater treatment, and aims to solve the problems of low catalyst use frequency, incomplete reaction, lack of a recovery device, low process automation degree and the like of the conventional catalytic oxidation wastewater treatment device. According to the catalytic oxidation wastewater treatment device based on the sludge-based biochar catalyst, a catalyst storage device, a feeding device and an oxidizing agent feeding device are all arranged on a reaction tank body, the discharging end of the catalyst storage device and the discharging end of the oxidizing agent feeding device are all communicated with an inner cavity of the reaction tank body, and a stirrer is rotationally connected into the inner cavity of the reaction tank body; the magnetic attraction recovery device is arranged at a bottom plate of an inner cavity of the reaction tank body and is placed in a slope shape, the deactivated catalyst storage device is arranged at the bottom of the outer surface of the reaction tank body and is communicated with the inner cavity of the reaction tank body, and the bottom of the slope of the magnetic attraction recovery device faces a feeding pipe of the deactivated catalyst storage device. The device has the advantages of simple structure, high automation degree and multiple catalyst circulation times.

Description

Technical Field

[0001] The utility model belongs to the technical field of organic polluted wastewater treatment, and particularly relates to a catalytic oxidation wastewater treatment device based on a sludge-based biochar catalyst. Background Technique

[0002] At present, organic polluted wastewater has the characteristics of complex composition, various types and extremely difficult treatment. Traditional treatment methods have complex processes, low efficiency and limited treatment effects. The catalytic oxidation treatment process can efficiently remove refractory pollutants in wastewater under mild reaction conditions and has strong pertinence. However, at present, this process lacks efficient, green and stable catalysts. Although supported metal catalysts have high activity, they have problems such as high cost and easy loss of active components.

[0003] In recent years, biochar has received wide attention in the field of catalytic oxidation wastewater treatment due to its advantages such as wide source, low cost, high specific surface area, sufficient active sites and stable chemical properties. Among them, sludge is a waste discharged from sewage treatment plants, but at the same time, it is also a good biochar resource. The preparation of sludge-based biochar can fully reflect the green environmental protection concept of "treating waste with waste". Due to the high ash content of sludge, there are many metal components, which can form metal active components of the catalyst after high-temperature carbonization. In addition, conductive graphite carbon and oxygen-containing functional groups with redox activity are also formed.

[0004] Sludge-based biochar can act as an electron donor, acceptor and mediator. The metal, heteroatom-doped carbon structure and functional groups of sludge-based biochar can act as electron transfer media to further improve the catalytic performance, catalyze and activate oxidants such as persulfate, hydrogen peroxide (H2O2) and ozone to generate sulfate radicals (SO4-·), hydroxyl radicals (·OH), superoxide radicals (·O 2 -) and singlet oxygen non-free radicals ( 1 1O2) and other strongly oxidizing free radicals, which can efficiently degrade organic pollutants in wastewater. And sludge-based biochar can be magnetically recovered due to its high magnetism, effectively avoiding problems such as secondary pollution and catalyst loss.

[0005] Existing catalytic oxidation wastewater treatment devices have problems such as low catalyst usage times, incomplete reactions, lack of recovery and low degree of process automation. Content of the Utility Model

[0006] In order to solve at least one of the above technical problems existing in the prior art, the utility model provides a catalytic oxidation wastewater treatment device based on a sludge-based biochar catalyst.

[0007] The utility model is realized by the following technical solutions: A catalytic oxidation wastewater treatment device based on a sludge-based biochar catalyst, which includes a reaction tank body, a catalyst reservoir, a dosing device, an oxidant dosing device, a stirrer, a magnetic recovery device and an inactivated catalyst storage; an inlet end and an outlet end are arranged on the side wall of the reaction tank body, and the two ports are respectively located at the upper and lower ends of the opposite sides of the reaction tank body. The catalyst reservoir, the dosing device and the oxidant dosing device are all arranged on the reaction tank body, and the discharge ends are all communicated with the inner cavity of the reaction tank body. The stirrer is rotatably connected in the inner cavity of the reaction tank body. The magnetic recovery device is arranged at the bottom plate of the inner cavity of the reaction tank body and is placed in an inclined shape. The inactivated catalyst storage is arranged at the bottom of the outer surface of the reaction tank body and is communicated with the inner cavity of the reaction tank body. The bottom of the inclined surface of the magnetic recovery device faces the feed pipe of the inactivated catalyst storage.

[0008] Preferably, the magnetic recovery device includes a magnetic tower, an inclined shell and an external circuit. The magnetic tower is located in the internal space of the inclined shell. The magnetic tower is composed of multiple annular magnets stacked from bottom to top in sequence to form a magnetic tower structure. As the space gradually shrinks upwards, the radius of each layer of annular magnet decreases in sequence, and the number of turns decreases in sequence; the annular magnet includes an inner iron core and an outer coil winding; the external circuit is connected to the coil winding and is used to provide power for the magnetic tower to generate magnetism, so as to be able to adsorb the sludge-based biochar catalyst.

[0009] Preferably, it further includes a control component, and the control component includes a PLC controller and a high-level gauge, a low-level gauge, an inlet water solenoid valve, a total outlet water solenoid valve, a sub-outlet water solenoid valve, a return water solenoid valve, a catalyst recovery solenoid valve, a COD detector and a intermediate relay KA1 that are electrically connected to the PLC controller;

[0010] The PLC controller is arranged at the upper end of the reaction tank body. The high-level gauge is arranged at the upper part of the inner wall of the reaction tank body and is flush with the liquid level required for catalytic oxidation. The low-level gauge is arranged at the lower part of the inner wall of the reaction tank body and is flush with the outlet end. The inlet end of the COD detector is arranged at the outlet end of the reaction tank body. The outlet end of the COD detector is respectively connected with a water outlet pipe and a return water pipe, and the return water pipe is connected with the inlet water pipe of the reaction tank body;

[0011] The inlet water solenoid valve, the total outlet water solenoid valve, the sub-outlet water solenoid valve and the return water solenoid valve are respectively installed on the inlet water pipe of the reaction tank body, the water outlet pipe in front of the COD detector, the water outlet pipe behind the COD detector and the return water pipe. The catalyst recovery solenoid valve is arranged on the feed pipe of the inactivated catalyst storage. The normally open contact of the intermediate relay KA1 is arranged on the external circuit;

[0012] The external circuit includes an AC power supply, a protection resistor, a transformer, an ammeter, and an indicator light. Among them, the transformer, the ammeter, the indicator light, and the normally open contact of the intermediate relay KA1 are connected in series between the positive pole of the AC power supply and the first end of the coil winding of the magnetic tower, and the protection resistor is arranged between the negative pole of the AC power supply and the second end of the coil winding of the magnetic tower.

[0013] Preferably, solenoid valves for controlling the opening or closing of their discharge ports are provided at the catalyst reservoir, the dosing device, and the oxidant dosing device.

[0014] Preferably, a water quality pretreatment device is provided at the water inlet pipe of the reaction tank body, and the water quality pretreatment device is located inside the connection point of the water inlet pipe and the water return pipe.

[0015] Preferably, the stirrer is a turbine stirrer; the upper part of its central shaft is connected to the stirring motor at the top of the reaction tank body, and the lower part is connected to a horizontal disk. Multiple flat blades are installed on the horizontal disk, and the stirring motor is electrically connected to the PLC controller.

[0016] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0017] The device has a simple structure, a high degree of automation, and a large number of catalyst circulation times. The sludge-based biochar is used as the catalyst. According to experimental data, the removal rate or conversion rate of the catalyst after multiple cycles of use for specific pollutants can still reach more than 80%, and the structure and performance can remain relatively stable, and it is not easy to undergo obvious degradation or inactivation, indicating that the catalyst has excellent reusability and can effectively reduce the replacement frequency and cost of the catalyst. At the same time, a water quality detector is installed at the water outlet end of the device. If the water quality does not meet the standard, it indicates that the repeatability of the catalyst has decreased. At this time, the catalyst recovery device needs to be started to replace the catalyst. On the one hand, by reducing the number of catalyst replacements and the amount of waste treatment, environmental pollution can be reduced; on the other hand, since the catalyst can be used for a long time without frequent replacement, production costs and operating expenses can be reduced. Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 It is the external structure diagram of the device;

[0020] Figure 2 It is the internal structure diagram of the device;

[0021] Figure 3 It is a schematic structural diagram of the bottom of the stirrer;

[0022] Figure 4 It is a detailed diagram of the magnetic adsorption recovery device;

[0023] Figure 5 It is a schematic diagram of the input and output at the PLC controller of this device;

[0024] Figure 6 It is a top view of the magnetic tower of the magnetic adsorption recovery device.

[0025] In the figure: 1 - reaction tank body; 2 - catalyst storage and dosing device; 3 - oxidant dosing device; 4 - stirrer; 5 - magnetic adsorption recovery device; 5.1 - magnetic tower; 5.2 - AC power supply; 5.3 - protection resistor; 5.4 - transformer; 5.5 - ammeter; 5.6 - indicator light; 6 - deactivated catalyst storage; 7 - high liquid level gauge; 8 - low liquid level gauge; 9 - inlet solenoid valve; 10.1 - total outlet solenoid valve; 10.2 - branch outlet solenoid valve; 11 - return water solenoid valve; 12 - catalyst recovery solenoid valve; 13 - COD detector; 14 - water quality pretreatment device; 15 - PLC controller. Specific implementation manners

[0026] Combined with the drawings in the embodiments of the present utility model, the technical solutions in the embodiments of the present utility model are clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all embodiments. Based on the embodiments of the present utility model, all other implementation manners obtained by those of ordinary skill in the art without making creative efforts belong to the scope protected by the present utility model.

[0027] It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those who are familiar with this technology to understand and read, and are not used to limit the limited conditions for the implementation of the present utility model. Therefore, they do not have technical essence. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that the present utility model can produce and the purposes that can be achieved, should fall within the scope covered by the technical content disclosed in the present utility model. It should be noted that in this specification, relational terms such as first and second are only used to distinguish one entity from several other entities, and do not necessarily require or imply any actual relationship or order between these entities.

[0028] The present utility model provides an embodiment:

[0029] A catalytic oxidation wastewater treatment device based on a sludge-based biochar catalyst, comprising a reaction tank body 1, a catalyst reservoir, a dosing device 2, an oxidant dosing device 3, a stirrer 4, a magnetic recovery device 5 and an inactivated catalyst storage tank 6; a water inlet end and a water outlet end are arranged on the side wall of the reaction tank body 1, and the two ports are respectively located at the upper and lower ends on the opposite sides of the reaction tank body 1. The catalyst reservoir, the dosing device 2 and the oxidant dosing device 3 are all arranged on the reaction tank body 1, and the discharge ends are all communicated with the inner cavity of the reaction tank body 1. The stirrer 4 is rotatably connected in the inner cavity of the reaction tank body 1. The magnetic recovery device 5 is arranged at the bottom plate of the inner cavity of the reaction tank body 1 and is placed in an inclined shape. The inactivated catalyst storage tank 6 is arranged at the bottom of the outer surface of the reaction tank body 1 and is communicated with the inner cavity of the reaction tank body 1. The bottom of the inclined surface of the magnetic recovery device 5 faces the feed pipe of the inactivated catalyst storage tank 6.

[0030] A water quality pretreatment device 14 is arranged at the water inlet pipe of the reaction tank body 1, and the water quality pretreatment device 14 is located inside the connection point of the water inlet pipe and the water return pipe. Solenoid valves for controlling the opening or closing of the discharge ports are arranged at the catalyst reservoir, the dosing device 2 and the oxidant dosing device 3. The stirrer 4 is a turbine stirrer; the upper part of its central shaft is connected to the stirring motor at the top of the reaction tank body 1, and the lower part is connected to a horizontal disc. Multiple flat blades are installed on the horizontal disc, and the stirring motor is electrically connected to the PLC controller 15.

[0031] In this embodiment, the magnetic recovery device 5 includes a magnetic tower 5.1, an inclined shell and an external circuit. The magnetic tower 5.1 is located in the internal space of the inclined shell. The material of the inclined shell is thin-walled carbon steel, and the inner and outer surfaces are sprayed with an anti-corrosion material. The magnetic tower 5.1 is composed of multiple annular magnets stacked from bottom to top in sequence to form a magnetic tower structure, and the magnetic force gradually decreases upwards along the space. The radius of each layer of annular magnet decreases in sequence, and the number of turns decreases in sequence; the annular magnet includes an inner iron core and an outer coil winding; the external circuit is connected to the coil winding and is used to provide power for the magnetic tower 5.1 to generate magnetism, so as to be able to adsorb the biochar catalyst.

[0032] It also includes a control component, and the control component includes a PLC controller 15 and a high-level gauge 7, a low-level gauge 8, a water inlet solenoid valve 9, a total water outlet solenoid valve 10.1, a branch water outlet solenoid valve 10.2, a water return solenoid valve 11, a catalyst recovery solenoid valve 12, a COD detector 13 and a intermediate relay KA1 that are electrically connected to the PLC controller 15; the signal of the COD detector 13 is XTCOD300.

[0033] The PLC controller 15 is set at the upper end of the reaction tank body 1. The high liquid level gauge 7 is set at the upper part of the inner wall of the reaction tank body 1 and is flush with the liquid level required for catalytic oxidation addition. The low liquid level gauge 8 is set at the lower part of the inner wall of the reaction tank body 1 and is flush with the water outlet end. The water inlet end of the COD detector 13 is set at the water outlet end of the reaction tank body 1. The water outlet end of the COD detector 13 is respectively connected with a water outlet pipe and a return pipe, and the return pipe is connected with the water inlet pipe of the reaction tank body 1;

[0034] The inlet water solenoid valve 9, the total outlet water solenoid valve 10.1, the sub-outlet water solenoid valve 10.2, and the return water solenoid valve 11 are respectively installed on the water inlet pipe of the reaction tank body 1, the water outlet pipe in front of the COD detector 13, the water outlet pipe behind the COD detector 13, and the return water pipe. The catalyst recovery solenoid valve 12 is set on the feed pipe of the deactivated catalyst storage 6. The normally open contact of the intermediate relay KA1 is set on the external circuit;

[0035] The external circuit includes an AC power supply 5.2, a protection resistor 5.3, a transformer 5.4, an ammeter 5.5, and an indicator light 5.6. Among them, the transformer 5.4, the ammeter 5.5, the indicator light 5.6, and the normally open contact of the intermediate relay KA1 are connected in series between the positive pole of the AC power supply 5.2 and the first end of the coil winding of the magnetic tower 5.1, and the protection resistor 5.3 is set between the negative pole of the AC power supply 5.2 and the second end of the coil winding of the magnetic tower 5.1.

[0036] Specific working principle:

[0037] First, the PLC controller controls the opening of the inlet water solenoid valve 9 of the reaction tank body 1, the solenoid valves at the catalyst reservoir, the dosing device 2, and the oxidant dosing device 3 to add industrial wastewater, catalyst, and oxidant (in this application, the addition amounts of the catalyst and oxidant are much smaller than that of the industrial wastewater, and the catalyst and oxidant are added in a single quantitative manner, that is, only the single addition amount is artificially placed in the catalyst reservoir, the dosing device 2, and the oxidant dosing device 3. Therefore, the catalyst and oxidant have been added before the industrial wastewater reaches the high liquid level position of the reaction tank body 1);

[0038] When the high liquid level gauge 7 detects that the liquid level of the reaction tank body 1 reaches the high liquid level, the high liquid level gauge 7 inputs this signal to the PLC controller 15. The PLC controller 15 controls the closing of the inlet water solenoid valve 9 of the reaction tank body 1, the solenoid valves at the catalyst reservoir, the dosing device 2, and the oxidant dosing device 3, and at the same time controls the operation of the stirring motor of the stirrer 4 to start stirring the industrial wastewater, catalyst, and oxidant. The PLC controller 15 has a built-in clock and can control the stirring time.

[0039] After the agitator 4 finishes stirring, the output terminal of the PLC controller 15 gives a high-level signal to the intermediate relay KA1. The coil of the intermediate relay KA1 is energized, and the normally open contact of the intermediate relay KA1 closes, conducting the external circuit. Then, the magnetic adsorption recovery device 5 generates magnetism to adsorb the sludge-based biochar catalyst in the reaction tank body 1. After the adsorption is completed (the PLC sets the adsorption time according to the built-in clock), the PLC controller 15 controls the total effluent solenoid valve 10.1 to open, and the treated industrial wastewater enters the COD detector 13 for detection. The COD detector 13 is used to detect the chemical oxygen demand in the water and compare the detection result with the chemical oxygen demand threshold built in the PLC controller 15 (the comparison is only a magnitude comparison, which is prior art here and will not be elaborated). If the detection result is within the chemical oxygen demand threshold, the PLC controller 15 controls the sub-effluent solenoid valve 10.2 to open, the water quality is qualified, and the water is discharged. After the low-level gauge detects a low-level signal, the low-level gauge inputs the signal to the PLC controller 15. The output terminal of the PLC controller 15 gives a low-level signal to the intermediate relay KA1. The coil of the intermediate relay KA1 loses power, the normally open contact of the intermediate relay KA1 disconnects, the external circuit is cut off, the magnetic adsorption recovery device 5 loses magnetism, and the sludge-based biochar catalyst is released and waits for the next water quality treatment. If the detection result is greater than the chemical oxygen demand threshold, it proves that the sludge-based biochar catalyst has been deactivated. The PLC controller 15 controls the return water solenoid valve 11 to open, the water quality is unqualified, and it returns to the inlet pipe and then enters the original industrial wastewater tank. After the low-level gauge detects a low-level signal, the output terminal of the PLC controller 15 gives a low-level signal to the intermediate relay KA1. The coil of the intermediate relay KA1 loses power, the normally open contact of the intermediate relay KA1 disconnects, the external circuit is cut off, the magnetic adsorption recovery device 5 loses magnetism, and the sludge-based biochar catalyst is released. At the same time, the PLC controller controls the catalyst recovery solenoid valve 12 to open to recover the deactivated sludge-based biochar catalyst.

[0040] The above is only the preferred specific implementation manner of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present utility model should be covered by the protection scope of the present utility model. Therefore, the protection scope of the present utility model should be subject to the protection scope of the claims.

Claims

1. A catalytic oxidation wastewater treatment device based on sludge-based biochar catalyst, characterized in that: It comprises a reaction tank (1), a catalyst storage device and a dosing device (2), an oxidant dosing device (3), a stirrer (4), a magnetic recovery device (5) and a deactivated catalyst storage device (6); the catalyst is a sludge-based biochar catalyst; A water inlet and a water outlet are arranged on the side wall of the reaction tank body (1), and the two ports are respectively located at the upper and lower ends of opposite sides of the reaction tank body (1); a catalyst storage device, a dosing device (2), and an oxidant dosing device (3) are all arranged on the reaction tank body (1), and the discharge ends are all connected to the inner cavity of the reaction tank body (1); an agitator (4) is rotatably connected to the inner cavity of the reaction tank body (1); a magnetic recovery device (5) is arranged on the bottom plate of the inner cavity of the reaction tank body (1) and is placed in an inclined shape; a deactivated catalyst storage device (6) is arranged at the bottom of the outer surface of the reaction tank body (1) and is connected to the inner cavity of the reaction tank body (1); and the bottom of the inclined surface of the magnetic recovery device (5) faces the feed pipe of the deactivated catalyst storage device (6).

2. A catalytic oxidation wastewater treatment device based on sludge-based biochar catalyst according to claim 1, characterized in that: The magnetic recovery device (5) comprises a magnetic tower (5.1), an inclined shell and an external circuit. The magnetic tower (5.1) is located in the internal space of the inclined shell. The magnetic tower (5.1) is composed of a plurality of annular magnets stacked in sequence from bottom to top to form a magnetic tower structure. As the space gradually decreases upward, the radius of each layer of the annular magnets decreases in sequence, and the number of turns decreases in sequence. The annular magnet comprises an internal iron core and an external coil winding. The external circuit is connected to the coil winding to provide power to the magnetic tower (5.1) to generate magnetism, thereby being able to adsorb the sludge-based biochar catalyst.

3. A catalytic oxidation wastewater treatment device based on sludge-based biochar catalyst according to claim 2, characterized in that: The control assembly also includes a PLC controller (15) and a high liquid level gauge (7), a low liquid level gauge (8), a water inlet solenoid valve (9), a total water outlet solenoid valve (10.1), a separate water outlet solenoid valve (10.2), a return water solenoid valve (11), a catalyst recovery solenoid valve (12), a COD detector (13) and an intermediate relay KA1 electrically connected to the PLC controller (15); The PLC controller (15) is arranged at the upper end of the reaction tank body (1), the high liquid level meter (7) is arranged at the upper part of the inner wall of the reaction tank body (1) and is flush with the added liquid level required for catalytic oxidation, the low liquid level meter (8) is arranged at the lower part of the inner wall of the reaction tank body (1) and is flush with the water outlet end, the water inlet end of the COD detector (13) is arranged at the water outlet end of the reaction tank body (1), the water outlet end of the COD detector (13) is respectively connected to a water outlet pipe and a water return pipe, and the water return pipe is connected to the water inlet pipe of the reaction tank body (1); The water inlet solenoid valve (9), the total water outlet solenoid valve (10.1), the branch water outlet solenoid valve (10.2), and the return water solenoid valve (11) are respectively installed on the water inlet pipe of the reaction tank body (1), the water outlet pipe at the front end of the COD detector (13), the water outlet pipe and the return water pipe at the rear end of the COD detector (13), the catalyst recovery solenoid valve (12) is arranged on the feed pipe of the deactivated catalyst storage device (6), and the normally open contact of the intermediate relay KA1 is arranged on the external circuit; The external circuit comprises an AC power source (5.2), a protective resistor (5.3), a transformer (5.4), an ammeter (5.5) and an indicator light (5.6), wherein the transformer (5.4), the ammeter (5.5), the indicator light (5.6) and a normally open contact of an intermediate relay KA1 are connected in series between the positive pole of the AC power source (5.2) and the first end of the coil winding of the magnetic tower (5.1), and the protective resistor (5.3) is arranged between the negative pole of the AC power source (5.2) and the second end of the coil winding of the magnetic tower (5.1).

4. A catalytic oxidation wastewater treatment device based on sludge-based biochar catalyst according to claim 1, characterized in that: The catalyst storage device, the dosing device (2) and the oxidant dosing device (3) are all provided with electromagnetic valves for controlling the opening or closing of the discharge ports thereof.

5. A catalytic oxidation wastewater treatment device based on sludge-based biochar catalyst according to claim 2, characterized in that: A water quality pretreatment device (14) is provided at the water inlet pipe of the reaction tank body (1), and the water quality pretreatment device (14) is located on the inner side of the connection point between the water inlet pipe and the return pipe.

6. A catalytic oxidation wastewater treatment device based on sludge-based biochar catalyst according to claim 1, characterized in that: The stirrer (4) is a turbine stirrer; The upper part of the central shaft is connected to the stirring motor on the top of the reaction tank body (1), and the lower part is connected to a horizontal disc, on which a plurality of straight blades are installed. The stirring motor is electrically connected to a PLC controller (15).

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