CN105523615A - Multistage intensified catalytic oxidation, reduction and aeration internal electrolysis reactor and application thereof - Google Patents

Abstract

The invention relates to a multi-stage enhanced catalytic oxidation-reduction aeration internal electrolysis reactor and its application. The reactor is sequentially provided with a sedimentation layer (1), a water inlet gas distribution layer (2), and a multi-stage filler layer (3) and the water outlet layer (4), the multi-stage packing layer (3) is filled with packing balls with built-in electrolytic packing; when the reactor treats waste water, acid is first added to the waste water to be treated to adjust the pH value to 3, Then enter the reactor from the water-inlet air-distributing layer (2). Compared with the prior art, the present invention has the advantages of convenient filler replacement, sufficient internal electrolysis reaction, space-saving reactor, and good treatment effect.

Description

A multi-stage enhanced catalytic redox aeration internal electrolysis reactor and its application

technical field

The invention relates to an internal electrolysis reactor and its application, in particular to a multi-stage enhanced catalytic redox aeration internal electrolysis reactor and its application.

Background technique

Micro-electrolysis is a primary battery composed of iron and carbon. Through the complex oxidation-reduction reactions on the positive and negative electrodes, the biodegradability of wastewater is improved by using the electrical enrichment, physical adsorption and flocculation of the primary battery itself, so as to achieve wastewater pretreatment. Purpose of processing.

In recent years, there have been more and more researches on internal electrolysis in China, especially in the treatment of wastewater from electroplating, printing and dyeing, and chemical dyes, and have been widely used in engineering applications. However, most of the productive internal electrolysis reactors are filters. Some of them use steel-lined FRP equipment, and some use reinforced concrete structures. It was found that the existing aeration internal electrolysis reactor (patent number ZL200520098793.1) and strong oxidation internal electrolysis reactor (patent number ZL20032011500.3) both use internal iron-carbon materials, and a large resistance water distribution system is installed at the bottom of the pool. There are following problems in the practical application of this type of internal electrolysis reactor:

(1) It is difficult to replace the packing

In the internal electrolysis reactor, carbon is not consumed as the cathode, and iron is converted into iron ions into the water as the anode. Therefore, the internal electrolysis mainly consumes iron. As the reaction time goes by, iron filings are continuously consumed. When the iron filings are reduced to a certain extent It will affect the treatment effect of internal electrolysis, and iron filings must be added. If iron filings are directly added from the top of the pool, the new iron filings and carbon particles cannot be fully mixed evenly, which will affect the treatment effect of internal electrolysis. If all the fillers are cleared out and the new fillers that have been mixed are reloaded, this process will require a lot of work in the actual process, and at the same time require a large site, which is difficult to implement.

(2) Blockage of the reaction column

With the increase of the operation time of the internal electrolysis flocculation bed, more and more suspended solids will be agglomerated in the filler, and the concentration of metal hydroxide and the adsorption of suspended solids will block the pores of the filler. Therefore, regular backwashing is required. Due to the large proportion of iron filings, a very large backwashing intensity is required. Therefore, larger equipment must be provided in the project, which increases the investment cost.

(3) Iron filings agglomeration

In the internal electrolysis flocculation bed, the most commonly used fillers are steel scrap and cast iron scrap. The carbon content of steel scrap is low, the internal electrolysis reaction is slow, and the treatment effect is poor; the cast iron scrap has high carbon content and the treatment effect is good, but iron scrap Low strength and easy crushing. With the increase of processing time, the particle size of iron chips gradually decreases. Due to the low strength of cast iron chips, it is easy to be crushed into powder and agglomerate, causing channel flow in the internal electrolytic flocculation bed. Processing efficiency is reduced.

(4) Sludge treatment

The internal electrolysis method is usually carried out under acidic conditions. Under acidic conditions, the consumption of iron filings is large, and a large amount of iron sludge will be produced during the process of reverse pH adjustment, which will add a certain burden to the sludge dehydration process. The sludge contains a large amount of iron. Come to certain questions. At present, waste slag is generally sent to ironworks for disposal or blended to make building materials. Iron mud is also considered to be used to make magnetic materials. The disposal of iron mud still needs to be further studied and practiced.

(5) After the project is enlarged, the processing effect decreases

Whether the structural design of the reactor is reasonable or not directly affects the effect of the micro-electrolysis reaction. Generally, most of the micro-electrolysis experiments carried out in the laboratory are in small containers, and the sewage can fully contact with the filler, and the reaction is relatively full; however, when micro-electrolysis is applied to actual projects, due to the enlargement of the reactor size, the reaction conditions Changes in the reaction process make it easy to occur short flow, dead angle, and iron filings compaction, resulting in insufficient reaction and a significant decline in the treatment effect.

(6) High daily maintenance and operation costs

Micro-electrolysis reactors are mainly divided into two types: fixed bed and stirred bed. The fixed bed is to fix the iron filings and carbon powder particles in the bed, so that the waste water passes through the iron-carbon filler layer in the bed to undergo micro-electrolysis reaction. The stirred bed generally uses a mixer to mix the wastewater with iron filings and carbon particles. Whether it is a fixed bed or a stirred bed, there is a problem of iron filings hardening, which affects the treatment effect. The hardening problem brings great difficulties to the daily maintenance and operation of the equipment, resulting in increased maintenance costs and operating costs.

(7) High energy consumption and low processing efficiency

The reason why micro-electrolysis technology can be widely used lies in its low energy consumption and high efficiency. However, there are many deficiencies in ordinary micro-electrolysis reactors, which lead to poor mixing, mass transfer and diffusion effects in the actual engineering reaction process, resulting in increased energy consumption of supporting equipment, increased drug consumption and equipment operating costs.

Contents of the invention

The object of the present invention is to provide a multi-stage enhanced catalytic redox aeration internal electrolysis reactor and its application in order to overcome the defects of the above-mentioned prior art.

The purpose of the present invention can be achieved through the following technical solutions:

A multi-stage enhanced catalytic oxidation-reduction aeration internal electrolysis reactor is used to treat wastewater. The reactor is sequentially provided with a sedimentation layer, a water inlet air distribution layer, a multi-stage packing layer and a water outlet layer from bottom to top. The multi-level packing layer is filled with packing balls with built-in electrolytic packing.

The filler ball and the inner electrolytic filler arranged in the filler ball meet the following requirements: after the inner electrolytic filler in the filler ball fully reacts, the filler ball floats; when the inner electrolytic filler in the filler ball does not fully react, the filler ball sinks.

The surface of the filler ball is distributed with micropores for fully contacting the waste water to be treated with the inner electrolytic filler, and the diameter of the micropores is smaller than the particle diameter of the inner electrolytic filler.

The multi-level packing layer is composed of a first-level packing layer, a second-level packing layer, a third-level packing layer and a fourth-level packing layer arranged sequentially from bottom to top.

The heights of the first-stage packing layer, the second-stage packing layer, the third-stage packing layer and the fourth-stage packing layer and the loading capacity of the packing balls satisfy: in the waste water treatment process, the pH value in the first-stage packing layer No more than 3.5, the pH value in the second-stage packing layer is not more than 4.5, the pH value in the third-stage packing layer is not more than 5.5, and the pH value in the fourth-stage packing layer is not more than 6.5.

The water inlet air distribution layer includes an air distribution assembly and a water inlet assembly arranged on the air distribution assembly. The air distribution assembly is formed by a plurality of air distribution pipes connected to external air intake components arranged at intervals towards the same circle center, so The water inlet assembly described above is formed by a plurality of water inlet pipes connected to external water inlet components arranged at intervals towards the same circle center.

The upper surface of the air distribution pipe is provided with multiple groups of air distribution hole units arranged side by side, the air distribution hole units are formed by uniformly spaced air distribution holes, and the air distribution holes on the air distribution hole units of two adjacent groups are arranged in a dislocation;

The upper surface of the water inlet pipe is provided with multiple sets of water inlet units arranged side by side. The water inlet units are formed by evenly spaced water inlets. misplaced layout.

The water outlet layer includes a filter bag for eliminating foam laid on the top of the multi-stage packing layer, and a water collection weir arranged on the filter bag assembly for uniformly collecting the outlet water, and the water outlets of the water collection weir are respectively connected to the foam Outlet and liquid outlet, the shape of the filter bag matches the inner section of the reactor.

The bottom of the sedimentation layer is provided with a funnel-shaped sludge collection assembly, and the sewage outlet of the sludge collection assembly is provided with a sewage discharge screw for controlling the switch.

The multi-stage enhanced catalytic redox aeration internal electrolysis reactor is used to treat wastewater. When treating wastewater, the wastewater to be treated is first added with acid to adjust the pH value to 3, and then enters the reactor from the inlet air distribution layer.

Compared with the prior art, the present invention has the following advantages:

(1) The filler is fully utilized and the replacement of the filler is convenient: the inner electrolytic filler in the multi-level filler layer in the present invention is added by being arranged in the filler ball, so that the inner electrolytic filler participates in the inner electrolysis reaction in the form of a filler ball unit, Not only can it ensure a larger surface area for reaction participation, but it can also effectively prevent a large number of fillers from agglomerating and clogging during the reaction process. In addition, as the inner electrolytic filler is consumed by the internal electrolytic reaction of the filler ball, the relative density of the filler ball will change. Small, under the action of hydraulic force and air flotation, it gradually floats up to the upper part of each layer. When the filler needs to be replaced after a period of reaction, stop the water intake, discharge it through the inlet and outlet of each layer, and then add some new filler through the inlet and outlet of each layer as needed. ball. New filler balls and under-reacted filler balls then sink, so that the replacement of the filler can be well realized by taking out the filler balls floating on the filler layers of various levels and putting in new filler balls.

(2) the setting of the multi-stage packing layer of the present invention makes the reaction of the industrial wastewater to be treated in the upward treatment process be a graded reaction, wherein, the wastewater that just enters the reaction adds acid to adjust the pH value to 3, and the pH in the process is from 3 rises to 4, then rises from 4 to 5, and then rises from 5 to about 6. According to the principle of internal electrolysis and electrochemistry, the main reduction reaction occurs at pH=3-4; oxidation reaction and reduction reaction occur at pH=4-5 ; pH = 5-6 mainly oxidation reaction. Hierarchical reaction is one of the main features of this reactor. In traditional internal electrolysis reactors, all the fillers are generally piled up in the reactor, and the fillers are piled up in disorder. Due to the enlarged reaction size and the change of reaction conditions, it is easy to occur during the reaction process. Short flow, dead angle, iron filings compaction, etc., resulting in insufficient reaction and poor treatment effect. In addition, the reaction process carried out in the reactor is relatively complicated, and the pollutants cannot be degraded by making full use of the different reaction processes carried out by gradually increasing the pH. The reactor is equipped with multi-stage packing layers, which can strictly divide the treatment process into multi-stage reaction processes in terms of time and space. The pollutants undergo different reactions under different conditions and are gradually degraded, thereby improving the treatment efficiency. In addition, setting multi-stage fillers and filler balls can increase the reaction contact area, prevent filler agglomeration, and avoid insufficient reaction and poor treatment effect caused by short flow dead angles.

(3) The present invention is equipped with a water inlet component and an air distribution component at the bottom of the reactor, which can realize uniform gas distribution and water intake. In addition, the setting of the gas distribution component can not only provide the oxygen necessary for the internal electrolysis reaction, but also effectively Realize the full agitation of the waste water to be treated and the filler ball, prevent the occurrence of dead angles, and improve the adequacy of the internal electrolysis reaction.

(4) The arrangement of the multi-stage packing layer in the middle part, the number of stages of the packing layer is set according to the pH value of the feed water, so that the space of the reactor can be fully utilized. The setting of multi-stage packing layers divides the treatment process into several different processes. Since the pH of each stage is different, the reaction process is also different. The sewage passes through the multi-stage packing layers from bottom to top, and the pollutants in the sewage are different in each packing layer. Different reactions are carried out under the reaction conditions, and the reaction process is divided into multiple levels in time and space; setting multi-stage fillers and filler balls can increase the reaction contact area, prevent filler agglomeration, and avoid insufficient reaction caused by short flow dead angles. Therefore, the space of the reactor can be fully utilized, and the processing efficiency can be improved.

(5) The part of the water outlet layer adjacent to the multi-stage packing layer is equipped with a filter bag with built-in adsorption material, which can effectively eliminate the foam generated in the wastewater treatment process. At the same time, the water collection weir can also intercept part of the suspended matter. The form of liquid outlet separation can effectively realize the separation of treated waste water and foam.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is a schematic structural view of the air distribution assembly of the present invention;

Fig. 3 is the structural representation of air distribution pipe of the present invention;

Fig. 4 is the structural representation of the water inlet assembly of the present invention;

Fig. 5 is the structural representation of water inlet pipe of the present invention;

Fig. 6 is the processing effect figure of the present invention;

In the figure, 1-sedimentation layer, 2-water inlet air distribution layer, 3-multi-stage packing layer, 4-water outlet layer, 11-sludge collection component, 12-drainage screw, 21-air distribution component, 22-water inlet Components, 31-first-stage packing layer, 32-second-stage packing layer, 33-third-stage packing layer, 34-fourth-stage packing layer, 35-packing support, 41-filter bag, 42-collection weir, 43-steel mesh, 44-liquid outlet, 45-foam outlet, 211-air distribution pipe, 212-air distribution hole, 311-water inlet pipe, 312-water inlet hole, 311-first-level packing inlet and outlet, 312-first-level packing maintenance Port, 321-secondary packing import and export, 322-secondary packing inspection port, 331-tertiary packing import and export, 332-third packing inspection port, 341-fourth packing import and export, 342-fourth packing inspection port.

detailed description

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

Example 1

A multi-stage enhanced catalytic oxidation-reduction aeration internal electrolysis reactor, the structure of which is shown in Figure 1, is used to treat wastewater. The reactor is sequentially equipped with sedimentation layer 1, water inlet and gas distribution layer 2, and multi-stage packing from bottom to top. layer 3 and outlet layer 4.

The sediment layer 1 is provided with a funnel-shaped sludge collection assembly 11 at the bottom, and the sewage outlet of the sludge collection assembly 11 is provided with a sewage discharge screw 12 for controlling the switch, and the included angle of the section of the sludge collection assembly 11 is 155° .

The water inlet air distribution layer 2 includes an air distribution assembly 21 and a water inlet assembly 22 arranged on the air distribution assembly 21. The air distribution assembly 21 is formed by 12 air distribution pipes 211 connected to the external air intake parts and arranged at intervals toward the same circle center. The water assembly 22 is composed of 12 water inlet pipes 311 connected to the external water inlet parts, which are arranged at intervals towards the same circle center. The upper surface of the air distribution pipe 211 is provided with two groups of air distribution hole units arranged side by side. The air distribution hole units are arranged by the air distribution holes 212 at even intervals Formed, the air distribution holes 212 on the air distribution hole units of the two groups are misplaced, as shown in Figure 2 and Figure 3;

The upper surface of the water inlet pipe 311 is provided with two groups of water inlet units arranged side by side. The water inlet units are formed by uniformly spaced water inlet holes 312. As shown in Figure 4 and Figure 5.

The multi-stage packing layer 3 is composed of the first-stage packing layer 31, the second-stage packing layer 32, the third-stage packing layer 33 and the fourth-stage packing layer 34 arranged on the packing support 35 from bottom to top, the first-stage packing The heights of the layer 31, the second-stage packing layer 32, the third-stage packing layer 33 and the fourth-stage packing layer 34 and the loading capacity of the packing balls meet: during the wastewater treatment process, the pH value in the first-stage packing layer 31 does not exceed 3.5, the pH value in the second packing layer 32 does not exceed 4.5, the pH value in the third packing layer 33 does not exceed 5.5, the pH value in the fourth packing layer 34 does not exceed 6.5, the multi-stage packing layer 3 Filling balls filled with built-in electrolytic fillers, the filler balls and the inner electrolytic fillers arranged in the filler balls meet the requirements: after the inner electrolytic fillers in the filler balls fully react, the filler balls float up; when the inner electrolytic fillers in the filler balls do not fully react, the fillers The ball sinks, and the surface of the filler ball is distributed with micropores for fully contacting the waste water to be treated with the inner electrolytic filler, and the pore size of the micropores is smaller than the particle size of the inner electrolytic filler. The primary filler inlet and outlet 311, the secondary filler for taking out or replenishing filler balls are set on the top of the first-grade filler layer 31, the second-grade filler layer 32, the third-grade filler layer 33, and the fourth-grade filler layer 34, respectively. The inlet and outlet 321, the inlet and outlet of the tertiary packing 331 and the inlet and outlet of the fourth packing 341, the lower part is provided with the first packing inspection port 312, the second packing inspection port 322, the third packing inspection port 332 and the fourth packing inspection port for maintenance 342.

The water outlet layer 4 includes a filter bag 41 for eliminating foam that is laid on the top of the multi-stage packing layer 3, and a water collection weir 42 that is arranged on the filter bag 41 assembly for uniformly collecting water, and the water outlet of the water collection weir 42 The foam outlet 45 and the liquid outlet 44 are respectively connected, and the shape of the filter bag 41 matches the inner section of the reactor.

The above multi-stage enhanced catalytic redox aeration internal electrolysis reactor is used to treat wastewater. When treating wastewater, the wastewater to be treated is firstly added with acid to adjust the pH value to 3, and then enters the reactor from the water inlet gas distribution layer.

The biochemical effluent of industrial sewage was treated by using the multi-stage enhanced catalytic redox aeration internal electrolysis reactor of the above embodiment, and the experimental water was taken from the biochemical effluent of a printing and dyeing factory. The biochemical effluent quality of the printing and dyeing plant is: COD _Cr 320mg/L, and the chroma is 300 times. Using the multi-stage enhanced catalytic internal electrolysis reactor and ordinary beaker experiment, and compare the treatment efficiency of the waste water between the two, the two are tested under their optimal conditions. The results are compared as follows:

The multi-stage enhanced catalytic internal electrolysis reactor is better than the conventional beaker experiment in removing _{COD Cr} and chroma in the biochemical effluent of printing and dyeing wastewater. The COD _Cr removal rate is up to 50%, and the chroma removal rate is up to 80%. See Figure 6.

The above descriptions of the embodiments are for those of ordinary skill in the art to understand and use the invention. It is obvious that those skilled in the art can easily make various modifications to these embodiments, and apply the general principles described here to other embodiments without creative efforts. Therefore, the present invention is not limited to the above-mentioned embodiments. Improvements and modifications made by those skilled in the art according to the disclosure of the present invention without departing from the scope of the present invention should fall within the protection scope of the present invention.

Claims (10)

1. a multistage fortifying catalytic redox aeration Inner electrolysis reactor, for the treatment of waste water, it is characterized in that, described reactor sets gradually the beds of precipitation (1), water inlet cloth gas-bearing formation (2), multistage packing layer (3) and water-yielding stratum (4) from top to bottom, is filled with the filling ball of built-in Inner electrolysis filler in described multistage packing layer (3).

2. one according to claim 1 multistage fortifying catalytic redox aeration Inner electrolysis reactor, it is characterized in that, described filling ball and the Inner electrolysis filler be arranged in filling ball meet: after in filling ball, Inner electrolysis filler fully reacts, filling ball floats; When in filling ball, Inner electrolysis filler does not fully react, filling ball sinks.

3. one according to claim 1 multistage fortifying catalytic redox aeration Inner electrolysis reactor, it is characterized in that, the surface arrangement of described filling ball has the micropore for making pending waste water fully contact with Inner electrolysis filler, the aperture of this micropore to be less than the particle diameter of Inner electrolysis filler.

4. one according to claim 1 multistage fortifying catalytic redox aeration Inner electrolysis reactor, it is characterized in that, described multistage packing layer (3) is made up of the first step packing layer (31) set gradually from top to bottom, second stage packing layer (32), third stage packing layer (33) and fourth stage packing layer (34).

5. one according to claim 4 multistage fortifying catalytic redox aeration Inner electrolysis reactor, it is characterized in that, described first step packing layer (31), second stage packing layer (32), the height of third stage packing layer (33) and fourth stage packing layer (34) and the loading capacity of filling ball meet: in wastewater treatment process, pH value in first step packing layer (31) is no more than 3.5, pH value in second stage packing layer (32) is no more than 4.5, pH value in third stage packing layer (33) is no more than 5.5, pH value in fourth stage packing layer (34) is no more than 6.5.

6. one according to claim 1 multistage fortifying catalytic redox aeration Inner electrolysis reactor, it is characterized in that, described water inlet cloth gas-bearing formation (2) comprises cloth pneumatic module (21) and is arranged on the water inlet component (22) on cloth pneumatic module (21), described cloth pneumatic module (21) to be spaced towards the same center of circle by the many gas distribution pipes (211) connecting external feed stream parts and to form, and described water inlet component (22) to be spaced towards the same center of circle by the many water inlet pipes (311) connecting outside water inlet member and to form.

7. one according to claim 6 multistage fortifying catalytic redox aeration Inner electrolysis reactor, it is characterized in that, the upper face of described gas distribution pipe (211) is provided with the many groups of qi-emitting hole unit be arranged side by side, this qi-emitting hole unit is arranged by qi-emitting hole (212) uniform intervals and forms, and the qi-emitting hole (212) on the qi-emitting hole unit of two adjacent groups shifts to install;

The upper face of described water inlet pipe (311) is provided with the many groups of prosopyle unit be arranged side by side, this prosopyle unit is arranged by prosopyle (312) uniform intervals and forms, and prosopyle (312) dislocation on the prosopyle unit of two adjacent groups is arranged.

8. one according to claim 1 multistage fortifying catalytic redox aeration Inner electrolysis reactor, it is characterized in that, described water-yielding stratum (4) comprises the filter bag (41) for eliminating foam being laid in multistage packing layer (3) top, and the water collecting dike for uniform collection water outlet (42) be arranged on filter bag (41) assembly, the water outlet of water collecting dike (42) connects foam outlet (45) and liquid exit (44) respectively, and the shape of described filter bag (41) is consistent with the interior cross-sections match of reactor.

9. one according to claim 1 multistage fortifying catalytic redox aeration Inner electrolysis reactor, it is characterized in that, the described beds of precipitation (1) are provided with in funnel shaped mud collection assembly (11) in bottom, the sewage draining exit place of this mud collection assembly (11) is provided with the blowdown screw (12) for trip switch.

10. the multistage fortifying catalytic redox aeration Inner electrolysis reactor as described in as arbitrary in claim 1 ~ 9 is for the treatment of waste water, it is characterized in that, during process waste water, it is 3 that pending waste water first adds acid for adjusting pH value, then enters reactor from water inlet cloth gas-bearing formation (2).