CN107162158A - A kind of fluid bed Fenton reactor and method - Google Patents

Abstract

The invention discloses a fluidized bed Fenton reactor and a method thereof, which solve the problems of crystal loss and uneven water distribution in the prior art, and have the beneficial effects of reducing operating costs and improving the removal rate of refractory organic matter in sewage , the scheme is as follows: a fluidized bed Fenton reactor, including a reaction tank, the bottom of the reaction tank is provided with a catalyst inlet for raw water and catalyst to enter and an oxidant inlet for raw water and oxidant to enter, the catalyst inlet and the first The water distribution head is connected, the oxidant inlet is connected with the second water distribution head, a microporous aeration head is provided on the side of the first water distribution head in the reaction tank, and a main reaction area is arranged above the microporous aeration head in the reaction tank, and the main reaction area Packing is provided inside, and a three-phase separator is provided above the main reaction zone.

Description

A kind of fluidized bed Fenton reactor and method

technical field

The invention relates to the field of environmental protection equipment, in particular to a fluidized bed Fenton reactor and a method.

Background technique

In sewage treatment, especially in some industrial sewage treatment, some water quality that is difficult to degrade biochemically is often encountered. At present, the common methods to deal with these water quality are:

1. Advanced oxidation methods, including ozone oxidation, Fenton reagent oxidation, hydrogen peroxide oxidation, etc., directly oxidize and degrade refractory organic matter in wastewater;

2. Micro-electrolysis methods, such as iron-carbon micro-electrolysis, use the electrons generated by micro-electrolysis to open some groups of organic matter and decompose them into small molecular substances, which is beneficial to subsequent biochemical treatment;

3. Distillation method, distilling high-concentration salt-containing mother liquor, etc., to reduce inorganic salts in wastewater that have an inhibitory effect on biochemical bacteria, so as to facilitate subsequent biochemical treatment.

Comprehensive operating costs and investment costs, most of the advanced oxidation methods are used at present, and the Fenton reagent oxidation method is the most used among them.

At present, there are two main types of Fenton reagent oxidation method, one is the traditional Fenton oxidation method, and the other is the fluidized bed Fenton oxidation method represented by Taiwan Mercury. The Fenton fluidized bed can make the Fenton method Most of the ferric iron produced is coated on the surface of the filler (carrier) of the fluidized bed with crystallization or precipitation, and the FeOOH formed on the surface of the carrier has a heterogeneous catalytic effect, and the fluidized bed method also promotes chemical reaction. Oxidation reaction and mass transfer efficiency improve COD removal rate.

Compared with the traditional oxidation method, the biggest advantage of the fluidized bed Fenton oxidation method is that it saves chemicals and produces less sludge, so it is also used more and more.

However, the fluidized bed Fenton oxidation method still has the following shortcomings:

First, in order to keep the crystals in the sewage in a fluidized state, the waste water needs to maintain a relatively high flow rate, and in order to ensure a certain reaction time, it is generally used to increase the flow rate of the waste water to increase the flow rate, which increases the energy consumption;

Second, due to the inconsistent size and density of the crystals in the water, some crystals will be lost with the effluent, affecting the quality of the effluent and increasing the difficulty and cost of subsequent treatment;

The third is that the most uniform water distribution method is the multi-point water distribution method. However, since the lengths of the pipelines to each point are different, the number and size of the elbows and variable diameters used are also different, so it is difficult to ensure that the distribution of water at each point The water volume is consistent, so the flow rate in the tank is uneven and the fluidization effect is not good;

Fourth, the oxidant and catalyst in the Fenton reactor are mixed before the main reaction zone, and the prematurely generated hydroxyl radicals cause oxidative corrosion to pipelines, pipe fittings and equipment, and also reduce the efficiency of removing refractory organic matter in water.

Contents of the invention

In order to overcome the deficiencies of the prior art, the invention provides a fluidized bed Fenton reactor, which has less crystal loss, uniform water distribution, and avoids oxidation and corrosion of pipelines, fittings and equipment.

A specific scheme of a fluidized bed Fenton reactor is as follows:

A fluidized bed Fenton reactor comprising:

Reaction tank, the bottom of the reaction tank is provided with a catalyst inlet for raw water and catalyst and an oxidant inlet for raw water and oxidant. The catalyst inlet is connected to the first distribution head, and the oxidant inlet is connected to the second distribution head. In the reaction tank A microporous aeration head is provided on the side of the first water distribution head in the body, and a main reaction area is provided above the microporous aeration head in the reaction tank, and a filler is provided in the main reaction area, and a three-phase separator is provided above the main reaction area. The setting of the three separators can prevent the loss of crystals and discharge the gas in the tank through the exhaust pipe.

The gas setting in the reactor is used to increase the speed of water flow in the reaction tank, and fully stir and mix the mixture of catalyst, oxidant and raw water (sewage), so that the catalyst and oxidant are mixed evenly, which is conducive to the generation of hydroxyl radicals. , the inflated gas is air, and the oxygen in the air can also oxidize part of the COD in the sewage. Using air to increase the flow rate in the tank can greatly save energy compared to increasing the sewage return ratio.

The bottom of the main reaction zone is provided with a support plate, and the first water distribution head and the second water distribution head are both arranged on the support plate.

The first water distribution head and the second water distribution head are respectively provided in multiples, and the first water distribution head and the second water distribution head are uniformly staggered. The staggered arrangement is conducive to the further uniform distribution of sewage, and the first water distribution head and the second water distribution head maintain A certain pressure, about 0.15-0.2MPa, can ensure that the pressure at the water inlet of each water distribution head is the same, the water output of each water distribution head is the same, and the water distribution is very uniform. The first water distribution head is a long-handle cloth water head, and the second The cloth water head is a short handle cloth water head.

The microporous aeration head is arranged on the support plate, so that two cavities are arranged below the support plate of the reaction tank, the side of the lowermost cavity is provided with a catalyst inlet, and the upper cavity is provided with the oxidant inlet. .

The microporous aeration head is connected with an air inlet pipe, and the air inlet of the air inlet pipe is arranged on the upper part of the support plate in the main reaction zone, and the air inlet is used to feed gas, and the gas is provided by external equipment such as an air compressor.

The upper part of the three-phase separator in the reaction tank is provided with an overflow weir, and the arrangement of the overflow weir facilitates drainage.

The overflow weir is provided with a water outlet.

The three-phase separator communicates with the exhaust pipe passing through the reaction tank for gas discharge, and the three-phase separator is equipped with a gas collection hood, which is used for gas collection.

There are multiple microporous aeration heads, which are evenly arranged, and the microporous aeration heads can also be microporous aeration tubes, perforated tubes, etc.

In order to overcome the deficiencies in the prior art, the present invention also provides a kind of sewage treatment method, adopts a kind of fluidized bed Fenton reactor, comprises the following steps:

1) Raw water with a good pH value, part of the sewage is evenly mixed with the catalyst, and the other part of the sewage is evenly mixed with the oxidant, and enters the reaction tank through the catalyst inlet and the oxidant inlet respectively, and then enters the tank through the first water distribution head and the second water distribution head respectively body main reaction zone;

2) The gas enters the reaction tank through the microporous aeration head, and the two liquids are fully mixed under the stirring of the gas, and react to generate hydroxyl radicals, which decompose or oxidize refractory substances in the sewage; at the same time, the tank body The filler is also fluidized in the upward flow of water and air, the sewage is in full contact with the filler, and the catalyst ions form crystals on the surface of the filler;

3) When sewage, packing and gas flow to the three-phase separator on the upper part of the reaction tank, the packing is blocked, and then fall back to the main reaction area; the gas is collected by the three-phase separator, and then discharged through the exhaust pipe; the water passes through After the three separators enter the water outlet through the overflow weir and discharge, the process of Fenton oxidation of sewage is completed.

Compared with prior art, the beneficial effect of the present invention is:

1) The present invention solves the problems of high energy consumption, loss of crystals, uneven water distribution, and premature generation of hydroxyl radicals to oxidize and corrode pipelines, pipe fittings and equipment in the existing fluidized bed Fenton oxidation method for sewage treatment. , reducing operating costs and improving the removal rate of refractory organic matter in sewage.

2) In the present invention, raw water and oxidant, raw water and catalyst are mixed separately, and before the main reaction zone, to avoid premature generation of hydroxyl radicals to oxidize and corrode pipe fittings and equipment.

3) In the present invention, through the setting of multiple water distribution heads, the uniform water distribution is ensured, and the loss of crystals is avoided through the setting of the three-phase separator.

Description of drawings

The accompanying drawings constituting a part of the present application are used to provide further understanding of the present application, and the schematic embodiments and descriptions of the present application are used to explain the present application, and do not constitute improper limitations to the present application.

Fig. 1 is the overall structure schematic diagram of the invention.

FIG. 2 is a sectional view of FIG. 1 .

Among them: 1. Reaction tank body, 2. Three-phase separator, 3. Main reaction area, 4. Microporous aeration head, 5. Long handle cloth water head, 6. Short handle cloth water head, 7. Air inlet, 8 , catalyst inlet, 9, oxidant inlet, 10, filler, 11, water outlet, 12, overflow weir, 13, exhaust pipe.

detailed description

It should be pointed out that the following detailed description is exemplary and intended to provide further explanation to the present application. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It should be noted that the terminology used here is only used to describe specific implementations, and is not intended to limit the exemplary implementations according to the present application. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural, and it should also be understood that when the terms "comprising" and/or "comprising" are used in this specification, they mean There are features, steps, operations, means, components and/or combinations thereof.

As introduced in the background technology, there are deficiencies in the prior art. In order to solve the above technical problems, the present application proposes a fluidized bed Fenton reactor and its method.

In a typical implementation of the present application, as shown in Figure 1, a fluidized bed Fenton reactor includes a reaction tank 1, and the bottom of the reaction tank 1 is provided with a catalyst inlet 8 for raw water and a catalyst to enter and The oxidant inlet 9 for raw water and oxidant to enter, the catalyst inlet 8 is connected to the first water distribution head, the oxidant inlet 9 is connected to the second water distribution head, and a microporous aeration head is provided on the side of the first water distribution head in the reaction tank 1 4. The reaction tank body 1 is provided with a main reaction zone 3 above the microporous aeration head 4, and a filler 10 is provided in the main reaction zone 3, and a three-phase separator 2 is provided above the main reaction zone 3, and the three-phase separator 2 The setting can prevent the loss of crystals, and discharge the gas in the reaction tank body 1 through the exhaust pipe 13 .

The air distribution points of the air distribution system are evenly arranged in the reaction tank body 1, and the air distribution points can be microporous aeration heads 4, microporous aeration pipes, perforated pipes, etc., preferably microporous aeration heads. The air distribution system is used to increase the speed of the water flow in the tank, and fully stir and mix the mixture of catalyst, oxidant and raw water, so that the catalyst and oxidant are evenly mixed in the main reaction zone 3, which is conducive to the generation of hydroxyl radicals. In addition, The inflated gas is air, and the oxygen in the air can also oxidize part of the COD in the sewage. Using air to increase the flow rate in the reaction tank 1 can greatly save energy (generally referring to electricity consumption) compared to increasing the sewage reflux ratio.

The first cloth water head is a long-handle cloth water head, and the second cloth water head is a short-handle cloth water head, wherein the long-handle and short-handle cloth water heads are distributed alternately. The two cavities of the structure respectively accommodate the raw water mixed with catalyst and oxidant, and maintain a certain pressure, about 0.15-0.2MPa, which can ensure that the pressure at the water inlet of each distribution head is the same, and each distribution head The water output is consistent, and the water distribution is very uniform.

There is a set of gas, liquid and solid separators on the upper part of the reaction tank body 1, which can prevent the loss of crystals and discharge the gas in the tank through the exhaust pipe.

The filler inside the reaction tank body 1 is quartz sand with a particle size of 0.5-1.0mm.

When the reactor of the present invention is in operation, the raw water with a good pH value is mixed with the catalyst and the oxidant outside the Fenton reactor, and then enters the two chambers at the bottom of the reaction tank body 1, the catalyst enters the lower chamber, and the oxidant enters the upper chamber. , and then enter the main reaction zone 3 of the reaction tank 1 through the uniform and staggered distributed long and short handle cloth heads respectively. The two liquids are fully mixed under the stirring of the gas, and react to generate hydroxyl radicals, which decompose or Oxidize the refractory substances in the sewage; at the same time, the filler in the reaction tank 1 is also fluidized in the upward flow of water and air, the sewage is fully contacted with the filler, and the catalyst ions form crystals on the surface of the filler to prevent loss with the water flow. Save catalyst investment, reduce operating costs and reduce sludge generation.

Sewage, filler and gas (comprising the gas that air just reacts to produce), when flowing to the three-phase separator 2 on the upper part of the reaction tank body 1, the filler is blocked, and then falls back to the main reaction zone 3; the gas passes through the three-phase separator 2 The gas collecting hoods are collected together, and then discharged through the exhaust pipe 13; after the water passes through the three-phase separator 2, it enters the water outlet 11 through the overflow weir 12 and is discharged to complete the Fenton oxidation process.

The invention solves the problems of high energy consumption, loss of crystals, uneven water distribution, and premature oxidation and corrosion of pipelines, pipe fittings and equipment caused by the existing fluidized bed Fenton oxidation method for sewage treatment. The operation cost is reduced, and the removal rate of refractory organic matter in sewage is improved.

In order to overcome the deficiencies in the prior art, the present invention also provides a kind of sewage treatment method, adopts a kind of fluidized bed Fenton reactor, comprises the following steps:

1) Raw water with a good pH value, part of the sewage is evenly mixed with the catalyst, and the other part of the sewage is evenly mixed with the oxidant, and enters the reaction tank through the catalyst inlet and the oxidant inlet respectively, and then enters the tank through the first water distribution head and the second water distribution head respectively body main reaction zone;

2) The gas enters the reaction tank through the microporous aeration head, and the two liquids are fully mixed under the stirring of the gas, and react to generate hydroxyl radicals, which decompose or oxidize refractory substances in the sewage; at the same time, the tank body The filler is also fluidized in the upward flow of water and air, the sewage is in full contact with the filler, and the catalyst ions form crystals on the surface of the filler;

3) When sewage, packing and gas flow to the three-phase separator on the upper part of the reaction tank, the packing is blocked, and then fall back to the main reaction area; the gas is collected by the three-phase separator, and then discharged through the exhaust pipe; the water passes through After the three separators enter the water outlet through the overflow weir and discharge, the process of Fenton oxidation of sewage is completed.

The above descriptions are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, there may be various modifications and changes in the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included within the protection scope of this application.

Claims (10)

1. a kind of fluid bed Fenton reactor, it is characterised in that including：

Reacting tank body, reacting tank body bottom, which is provided with, is used for raw water with the catalyst inlet of catalyst entrance and for raw water and oxidation The oxidant inlet that agent enters, catalyst inlet is connected with the first water distribution head, and oxidant inlet is connected with the second water distribution head, anti- The first water distribution cephalic region in tank body is answered to be provided with micro porous aeration head, reacting tank body above micro porous aeration head provided with main reaction region, Filler is provided with main reaction region, three phase separator is provided with above main reaction region.

2. a kind of fluid bed Fenton reactor according to claim 1, it is characterised in that the bottom of the main reaction region is set There is supporting plate, first water distribution head, the second water distribution head are respectively provided with the supporting plate.

3. a kind of fluid bed Fenton reactor according to claim 1, it is characterised in that first water distribution head and second Water distribution head is respectively equipped with multiple, and the first water distribution head and the uniform interlaced arrangement of the second water distribution head.

4. a kind of fluid bed Fenton reactor according to claim 2, it is characterised in that the micro porous aeration head is located at branch On fagging.

5. a kind of fluid bed Fenton reactor according to claim 4, it is characterised in that the micro porous aeration head and air inlet Pipe is connected, and the air inlet of air inlet pipe is located at the top of supporting plate in main reaction region.

6. a kind of fluid bed Fenton reactor according to claim 1, it is characterised in that three-phase separate in the reacting tank body Downflow weir is provided with from device top.

7. a kind of fluid bed Fenton reactor according to claim 6, it is characterised in that the downflow weir is provided with water outlet Mouthful.

8. a kind of fluid bed Fenton reactor according to claim 1, it is characterised in that the three phase separator is with passing through The blast pipe connection of reacting tank body.

9. a kind of fluid bed Fenton reactor according to claim 1, it is characterised in that the micro porous aeration head is provided with more Individual, multiple micro porous aeration heads are evenly arranged.

10. a kind of sewage water treatment method, it is characterised in that using a kind of fluidisation according to any one of claim 1-9 Bed Fenton reactor, comprises the following steps：

1) raw water of pH value is mixed up, part of contaminated water is well mixed with catalyst, another part sewage is well mixed with oxidant, point Reacting tank body is not entered by catalyst inlet, oxidant inlet, then tank entered by the first water distribution head, the second water distribution head respectively Body main reaction region；

2) gas is entered in reacting tank body by micro porous aeration head, and two kinds of liquid are sufficiently mixed under the stirring of gas, is occurred anti- Should, hydroxyl radical free radical is produced, hydroxyl radical free radical decomposes or aoxidized hard-degraded substance in sewage；Meanwhile, the filler in tank body, During water, gas are flowed up, also fluidisation is got up, and sewage is fully contacted with filler, and catalyst ion is formed on filler surface and crystallized；

3) sewage, filler and gas, when flowing to three separators on reacting tank body top, filler is blocked, and is then fallen after rise back Main reaction region；Gas is collected by three phase separator, is then drained by blast pipe；Water passes through overflow after three separators Weir is discharged into delivery port, completes the sewage process of Fenton oxidation.