Six-grid type multiphase Fenton oxidation device

Abstract

The utility model discloses a six-grid type multiphase Fenton oxidation device. The device comprises a reaction tank, the interior of the reaction tank is divided into six areas with the same size in two rows and three columns by partition plates; wherein the three areas in the first row are a Fe < 2 + > regeneration area, a homogeneous Fenton reaction area and a coagulating sedimentation area in sequence; the coagulating sedimentation area is provided with a water inlet; the three areas in the second row are correspondingly provided with an induction Fenton area, a transition area and a water outlet area; wherein the coagulating sedimentation area, the homogeneous Fenton reaction area, the transition area and the water outlet area are sequentially communicated; the coagulating sedimentation area, the homogeneous Fenton reaction area, the transition area and the water outlet area are sequentially communicated. The multi-phase Fenton technology device does not add acid, produces less mud, escapes less Fe ions, has high oxidation efficiency on refractory organic matters, is an improvement and innovation on the traditional Fenton technology, and has important significance on expansion and application of the Fenton oxidation technology.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of refractory organic wastewater treatment technology, especially to a six-format multi-phase fenton oxidation device. BACKGROUND

[0002] At present, in the advanced oxidation technology of treating high-concentration multi-component organic wastewater, Fenton oxidation technology is unanimously recognized by the industry. The core of Fenton technology is to use hydroxyl radicals generated by the decomposition of hydrogen peroxide as an oxidant, and divalent iron ions as a catalyst to promote the decomposition of hydrogen peroxide. Add acid to adjust to pH = 3-5, and Fenton reaction occurs to produce hydroxyl radicals to oxidize and degrade refractory organic matter. After the reaction is completed, the iron ions are precipitated by adjusting the alkali. The pH value of the traditional Fenton technology has a narrow range of adaptation, a large amount of ferrous sulfate catalyst needs to be added, and the catalyst cannot be reused and will also form polluting iron sludge, which is easy to cause secondary pollution. On the basis of traditional Fenton technology, heterogeneous Fenton technology has been developed. The so-called heterogeneous is that the catalyst is in solid state, and then the heterogeneous Fenton fluidized bed technology has emerged. The core of this technology is the fluidization of solid catalyst, which uses the upward flow of fluid to make the catalyst particles suspended in water. Compared with the reaction kinetics of traditional homogeneous Fenton reaction, the reaction speed of heterogeneous Fenton system is slow, the oxidation efficiency is low, and the overall catalytic reaction rate is limited by the low efficiency of Fe 3+ and H2O2 reaction. The content of Fe 3+ in the heterogeneous Fenton system is high, which limits the overall efficiency of the Fenton reaction. Therefore, how to accelerate the reduction of Fe 3+ to Fe 2+ is the key to improving the efficiency of the heterogeneous Fenton system.

[0003] Pyrite (FeS2) is one of the most abundant metal sulfides in nature, which belongs to cubic system and contains FeS6 octahedron and S-S dimer. The S center atoms in pyrite usually appear in pairs, that is, S2 2- . However, the S-S bond in S2 2- is unstable and easy to break, and is easy to be oxidized. Under acidic conditions, Fe 3+ oxidizes FeS2 to produce Fe 2+ , and the following reaction occurs: FeS2+14Fe 3+ +8H2O→15Fe 2+ +2SO4 2- +16H + , which can accelerate the reduction of Fe 3+ to Fe 2+, to improve the efficiency of heterogeneous Fenton system. The Fenton-like reaction system with FeS2 as catalyst has two-stage degradation kinetics process, namely initial slow induction period and subsequent rapid oxidation period. The researchers believe that the induction period is a heterogeneous reaction, and the rapid oxidation period is a homogeneous reaction, and the reaction equation is: Fe 2+ +H2O2→Fe 3+ +·OH+OH - Such Fenton reaction is called heterogeneous Fenton system. A heterogeneous Fenton oxidation technology is developed with pyrite (FeS2) as catalyst. The heterogeneous Fenton technology device does not add acid, produces less mud, has less Fe ion escape, and has high oxidation efficiency for refractory organic matter. It is an improvement and innovation of traditional Fenton technology, and has important significance for the expansion and application of Fenton oxidation technology. Practical new type content

[0004] In order to overcome the above defects, the utility model provides a six format heterogeneous Fenton oxidation device.

[0005] In order to achieve the above object, the six format heterogeneous Fenton oxidation device of the utility model, the device includes a reaction tank;In the reaction tank, six equal-sized areas are divided into two rows and three columns by partitions;

[0006] Among them, the three areas of the first row are Fe2+ regeneration area, homogeneous Fenton reaction area and coagulation sedimentation area in turn;The coagulation sedimentation area is provided with a water inlet;

[0007] The three areas of the second row are correspondingly provided with induction Fenton area, transition area and effluent area;

[0008] Among them, the coagulation sedimentation area, the homogeneous Fenton reaction area, the transition area and the effluent area are sequentially communicated;The coagulation sedimentation area, the homogeneous Fenton reaction area, the transition area and the effluent area are sequentially communicated.

[0009] Further, the homogeneous Fenton reaction area is provided with a gas stripping device, and the gas stripping device is used to output the liquid in the homogeneous Fenton reaction area to the transition area;

[0010] The lower end of the partition between the transition area and the induction Fenton area is provided with a communication hole;

[0011] The upper partition between the induction Fenton area and the Fe2+ regeneration area is provided with a triangular weir;

[0012] The lower section of the partition between the Fe2+ regeneration area and the homogeneous Fenton reaction area is provided with a communication hole.

[0013] Further, the middle section of the partition between the coagulation sedimentation area and the homogeneous Fenton reaction area is provided with a communication hole;

[0014] A gas stripping device is arranged in the homogeneous Fenton reaction zone, and the gas stripping device is used to output the liquid in the homogeneous Fenton reaction zone to the transition zone;

[0015] The middle section of the partition plate between the transition zone and the water outlet zone is provided with a communication hole;

[0016] The lower section of the partition plate between the water outlet zone and the coagulation and sedimentation zone is provided with a communication hole;

[0017] The water outlet side of the water outlet zone is provided with an adjustable triangular weir.

[0018] Further, a hydrogen peroxide adding device is arranged in the homogeneous Fenton reaction zone.

[0019] Further, a FeS2 powder adding device is arranged on the induced Fenton zone.

[0020] Further, an OH - adding device is arranged in the transition zone.

[0021] Further, an OH - adding device is arranged in the water outlet zone.

[0022] The utility model has the following advantages:

[0023] (1) Compared with the traditional homogeneous Fenton technology, the heterogeneous Fenton technology and device do not need to add acid to adjust pH, the amount of FeS2 added is 1 / 14 (calculated by iron) of the amount of FeSO4 added in the traditional homogeneous Fenton technology, the generated iron sludge is also 1 / 14 (calculated by iron) of the traditional homogeneous Fenton technology, and can also be used as a coagulant for resource utilization;

[0024] (2) Compared with the traditional heterogeneous Fenton technology, the heterogeneous Fenton technology and device have less Fe ion escape, FeS2 has high efficiency in reducing Fe 3+ to Fe 2+ , the Fe-based catalyst has high recycling rate, has high catalytic efficiency on H2O2, and therefore has high efficiency in oxidizing and degrading refractory organic matter.

[0025] (3) The six-grid plate device of the utility model is a complete mixing type reactor, and the whole is a plug flow type reactor; 2, 3, 4 and 5 grids are internally circulating structures.

[0026] (4) The coagulant is not directly added, and the coagulation of iron hydroxide is generated in the Fenton reaction process, which is a new type of coagulation technology scheme;

[0027] (5) The homogeneous Fenton and heterogeneous Fenton occur simultaneously in the device, which is a new type of Fenton technology scheme;

[0028] (6) The water inlet and outlet of the device are on the same side of the device, and the ferric hydroxide coagulant is refluxed from the bottom of the water outlet area to the water inlet area. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 It is a structural schematic diagram of the system of the utility model.

[0030] Among them, 1, coagulation and sedimentation zone; 2, homogeneous Fenton reaction zone; 3, transition zone; 4, induced Fenton zone; 5, Fe2+ regeneration zone; 6, water outlet area DETAILED DESCRIPTION

[0031] The utility model embodiment will be described in detail below with reference to the drawings.

[0032] In the description of the utility model, it is understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the utility model.

[0033] The terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more features. In the description of the utility model, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0034] In the description of the utility model, it should be explained that, unless otherwise specified and limited, the terms "mounting", "connection" and "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected, it can be directly connected, or indirectly connected through an intermediate medium, or the communication between two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0035] Figure 1 It is a schematic diagram of the multiphase Fenton oxidation device of the utility model, as shown in the figure, the device comprises a reaction tank; the reaction tank is divided into two rows and three columns, a total of six equal-sized areas by a partition plate; Figure 1

[0036] Among them, the three areas of the first row are Fe2+ regeneration zone, homogeneous Fenton reaction zone and coagulation and sedimentation zone in turn; the coagulation and sedimentation zone is provided with a water inlet; ​

[0037] The three zones of the second row correspond to the induced Fenton zone, the transition zone and the effluent zone;

[0038] The coagulation sedimentation zone, the homogeneous Fenton reaction zone, the transition zone and the effluent zone are sequentially connected.

[0039] The middle section of the partition plate between the coagulation sedimentation zone and the homogeneous Fenton reaction zone is provided with a communication hole;

[0040] A gas stripping device is arranged in the homogeneous Fenton reaction zone, and the gas stripping device is used to output the liquid in the homogeneous Fenton reaction zone to the transition zone;

[0041] The middle section of the partition plate between the transition zone and the effluent zone is provided with a communication hole;

[0042] The lower section of the partition plate between the effluent zone and the coagulation sedimentation zone is provided with a communication hole;

[0043] The effluent side of the effluent zone is provided with an adjustable triangular weir.

[0044] Further, the lower end of the partition plate between the transition zone and the induced Fenton zone is provided with a communication hole;

[0045] The upper section of the partition plate between the induced Fenton zone and the Fe2+ regeneration zone is provided with a triangular weir;

[0046] The lower section of the partition plate between the Fe2+ regeneration zone and the homogeneous Fenton reaction zone is provided with a communication hole;

[0047] This way is conducive to the full mixing and reaction of the liquid in the reaction zone and the added FeS2 powder.

[0048] Further, a hydrogen peroxide dosing device is arranged in the homogeneous Fenton reaction zone; an FeS2 powder dosing device is arranged on the induced Fenton zone; an OH - dosing device is arranged in the transition zone; and an OH - dosing device is arranged in the effluent zone.

[0049] Working principle:

[0050] The multiphase Fenton oxidation technology uses pyrite (FeS2) as catalyst to remove the refractory organic matter in wastewater through six-stage reaction device. The wastewater containing refractory organic matter flows through the route of ①→②→③→⑥, and the Fenton reaction liquid flows through the route of ③→④→⑤→②. The first stage is the coagulation sedimentation zone, and the refractory organic wastewater with a flow rate of Q is subjected to coagulation reaction in the first stage, so that most of the colloidal substances and suspended substances in the organic wastewater are removed by coagulation sedimentation; the second stage is the homogeneous Fenton reaction zone, and the pH is controlled at about 3-5, and hydrogen peroxide is added, so that the homogeneous Fenton reaction occurs under the catalysis of divalent iron ions, and the refractory organic matter in the wastewater is oxidized and degraded; the third stage is the transition zone, in which the homogeneous Fenton reaction is completed, and the Fenton reaction liquid is formed, and 1 unit of OH - in the Fenton reaction liquid is added in the third stage to neutralize 1 unit of H + in the Fenton reaction liquid, so that the free hydrogen ions in the wastewater are neutralized, and 14Q Fenton reaction liquid enters the fourth stage; the fourth stage is the induced Fenton zone, in which 1 unit of FeS2 powder is added, and the fifth stage is the Fe 2+ regeneration zone, in which FeS2 and 14Fe 3+ react to generate 15Fe 2+ and 16H + , 15Fe 2+ and 16H + return to the second stage to react with the hydrogen peroxide added in the second stage to generate the homogeneous Fenton reaction liquid for oxidizing and degrading the refractory organic matter; the Q Fenton reaction liquid in the third stage enters the sixth stage for water discharge, and 3 units of OH - are added, so that Fe 3+ in the Fenton reaction liquid reacts with 3OH - to generate the coagulant Fe(OH)3, and the Fe(OH)3 returns to the first stage, and the purified water is discharged from the sixth stage.

[0051] The raw water enters the device from the lower part of the first stage coagulation sedimentation zone, and the Fe(OH)3 generated in the sixth stage is used as coagulant to coagulate and precipitate the raw water to be treated, so as to reduce the loss amount of Fe 3+ resulting from the coagulation reaction in the subsequent Fenton reaction process;

[0052] In the second stage homogeneous Fenton reaction zone, 15 units of hydrogen peroxide are added from the lower part of the second stage, and the Fe 2+ returned from the lower part of the fifth stage reacts with the hydrogen peroxide to generate ·OH, which oxidizes the refractory organic matter flowing into the middle part of the first stage;

[0053] The Fenton reaction liquid enters the third stage transition zone from the upper part of the second stage, and 1 unit of OH - is added to the upper part of the third stage to neutralize the remaining 1 unit of H+ Fenton reaction liquid with flow rate of 14Q is introduced into the fourth grid from the lower part to induce the Fenton zone, and Fenton reaction liquid with flow rate of Q is introduced into the sixth grid from the middle part to neutralize the effluent zone;

[0054] One unit of FeS2 powder is added into the fourth grid to induce the Fenton zone, and the FeS2 powder is uniformly dispersed in the fourth grid 3+ The reaction is fully mixed, and the FeS2 powder in the fourth grid is fully mixed with the Fenton reaction liquid introduced from the third grid 2+ The FeS2 powder is regenerated in the fifth grid 3+ The FeS2 powder is fully reduced to FeS 2+ and generates one equivalent of H + The pH is automatically adjusted to 3-5 to create conditions for the homogeneous Fenton reaction, and a blocking net should be arranged between the fifth grid and the second grid, the pore size of the blocking net is smaller than the particle size of the FeS2 powder, and the loss of the FeS2 powder is effectively reduced;

[0055] Three units of OH are added into the sixth grid to neutralize the effluent zone - The FeS2 powder introduced from the third grid into the sixth grid is neutralized 3+ The FeS2 powder is precipitated to generate Fe(OH)3 coagulant, and is backflowed to the first grid, and at this time, the effluent is neutral.

[0056] The utility model has been described in detail above in combination with the drawings, but the utility model is not limited to the above-mentioned embodiments, and various changes can be made within the knowledge range possessed by those skilled in the art without departing from the purpose of the utility model. Many other changes and modifications of the concept and range of the utility model should be considered as the protection range of the utility model.

[0057] In the description of the present specification, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0058] The above is only a specific implementation manner of the utility model, but the protection range of the utility model is not limited to this, and any skilled person in the art can easily think of changes or replacements within the technical range disclosed by the utility model, which should be covered in the protection range of the utility model. Therefore, the protection range of the utility model should be subject to the protection range of the claims.

Claims

1. A six-cell multiphase Fenton oxidation apparatus, characterized in that, The device includes a reaction tank; the reaction tank is divided into six equal-sized zones in two rows and three columns by partitions; The first row consists of three zones: the Fe2+ regeneration zone, the homogeneous Fenton reaction zone, and the coagulation and sedimentation zone; the coagulation and sedimentation zone is equipped with an inlet. The second row has three zones: an induction Fenton zone, a transition zone, and an outlet zone. The coagulation sedimentation zone, homogeneous Fenton reaction zone, transition zone, and effluent zone are sequentially connected.

2. The six-cell multiphase Fenton oxidation apparatus as described in claim 1, characterized in that, A gas-lifting device is provided in the homogeneous Fenton reaction zone, which is used to output the liquid in the homogeneous Fenton reaction zone to the transition zone. A connecting hole is provided in the lower section of the partition between the transition zone and the induced Fenton zone; A triangular weir is installed on the partition between the Fenton induced zone and the Fe2+ regeneration zone; A connecting hole is provided in the lower section of the partition between the Fe2+ regeneration zone and the homogeneous Fenton reaction zone.

3. The six-cell multiphase Fenton oxidation apparatus as described in claim 1, characterized in that, A connecting hole is provided in the middle section of the partition between the coagulation sedimentation zone and the homogeneous Fenton reaction zone; A gas-lifting device is provided in the homogeneous Fenton reaction zone, which is used to output the liquid in the homogeneous Fenton reaction zone to the transition zone. A connecting hole is provided in the middle section of the partition between the transition zone and the outlet zone; A connecting hole is provided at the lower end of the partition between the effluent zone and the coagulation sedimentation zone; An adjustable triangular weir is installed on the outlet side of the outlet area.

4. The six-cell multiphase Fenton oxidation apparatus as described in claim 1, characterized in that, A hydrogen peroxide dosing device is provided in the homogeneous Fenton reaction zone.

5. The six-cell multiphase Fenton oxidation apparatus as described in claim 1, characterized in that, A FeS2 powder dosing device is provided in the induced Fenton zone.

6. The six-cell multiphase Fenton oxidation apparatus as described in claim 1, characterized in that, OH is provided in the transition region. - Dosing device.

7. The multiphase Fenton oxidation apparatus according to claim 1, characterized in that, OH is installed in the effluent zone - Dosing device.

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