WO2018201304A1 - Wastewater treatment system and method for effective volume reduction of organic sludge - Google Patents

Abstract

A wastewater treatment system for effective volume reduction of organic sludge. The system comprises a bar screen, a sedimentation tank, a bio-reaction tank, and a sludge thickening tank. A hydrodynamic cavitation sludge minimization machine is connected in series between an outlet end of the sludge thickening tank and a feed of the bio-reaction tank to form a wastewater circulation system. The hydrodynamic sludge minimization machine comprises at least two stages of cavitation devices connected in series. A first-stage cavitation device (100) comprises a first cavitator (103) placed in a first-stage cavitation cavity (101) and a pulverization barrier plate (102) facing an outlet of the first cavitator (103). A second-stage cavitation device (20) comprises a second cavitator (21), a jet confining member (25), and a second-stage diffuser pipe (26) connected in sequence. The jet confining member (25) is located within an air dissolving cavity (23). The air dissolving cavity (23) is provided with an air dissolving adjustment mechanism. Also disclosed is a sludge minimization method.

Description

Sewage treatment system and method for effectively realizing organic sludge reduction Technical field

The invention relates to a sewage treatment system and method for reducing organic sludge, in particular to a sewage treatment system and method for reducing organic sludge by using a hydraulic cavitation sludge reducer.

Background technique

At present, most urban sewage and industrial organic wastewater are treated by biochemical processes. The biochemical processes used include: A2/O, A/O, SBR, oxidation ditch, MBR, and the like. However, the common problem with these methods is that a large amount of excess sludge is produced during the sewage treatment process. In general, for every 10,000 m ^{3 of} sewage treated, the process produces about 5-10 tons of mud cake with a moisture content of 80%. This sludge contains harmful substances such as pathogens, heavy metals and persistent organic matter. At present, most of this sludge is naturally piled up and has not been properly disposed of. Only a small amount of sludge is treated in different ways.

At present, the main sludge treatment technologies at home and abroad include incineration, landfill, anaerobic digestion, aerobic fermentation, hot-drying lime stabilization, sludge pyrolysis, and hydrothermal treatment. Both belong to the end treatment technology after the sludge is produced. These treatments will bring huge equipment investment and high operating costs, as well as secondary pollution and ecological safety risks. On average, China produces 80% of mud cakes per day over 500,000 tons. Due to the high cost of transportation, storage, treatment and disposal of sludge, there is no cost-effective treatment and disposal method, which results in less than 5% of the sludge being composted, incinerated and pyrolyzed. Heap or disorderly throwing, causing great harm to the environment. Therefore, there is a need for an equipment that reduces sludge production, especially in the process of sewage treatment, which can reduce sludge production, achieve source reduction, and it is urgent to carry out clean production.

Summary of the invention

The object of the present invention is to provide a sewage treatment system and method for reducing organic sludge by using a hydrodynamic cavitation reducer in the biochemical treatment process of sewage.

In order to achieve the above object, the present invention provides a sewage treatment system for effectively realizing reduction of organic sludge, comprising a grid, a grit chamber, a biological reaction tank and a sludge concentration tank which are sequentially connected, characterized in that: A hydraulic cavitation reducer is connected in series between the outlet end of the sludge thickening tank and the inlet of the biological reaction tank to form a sewage circulation system, and the inlet end of the hydraulic cavitation sludge reducer is connected to the sludge concentration An outlet end of the pool, the outlet end of the hydrodynamic cavitation reducer is connected to the inlet end of the biological reaction tank via a pipeline;

The hydrodynamic cavitation mud reducer comprises at least two stages of cavitation devices connected in series;

The first stage cavitation device comprises a first cavitation placed in the first cavitation chamber and a pulverizing baffle facing the first cavitation outlet;

The second stage cavitation device includes a second cavitation, a jet confinement and a secondary diffusion tube that are sequentially connected, the second cavitation is located in the heating chamber, and the jet confinement is located in the dissolved gas chamber, The dissolved gas chamber is provided with a dissolved gas regulating mechanism.

The hydrodynamic cavitation mud reducer further includes a third stage cavitation device and a fourth stage cavitation device; the second stage cavitation device, the third stage cavitation device and the fourth level cavitation device from top to bottom a vertical configuration; the first stage cavitation device is horizontally disposed and located above the second level cavitation device;

The first stage cavitation device is connected to the second stage cavitation device by a first support sealing plate; the second stage cavitation device is connected to the third stage cavitation device by a second support sealing plate; The third stage cavitation device is coupled to the fourth stage cavitation device via a third support seal.

The biological reaction tank comprises an anoxic tank and an aerobic tank connected in sequence, and an outlet end of the aerobic tank is connected to an inlet end of the anoxic tank via a pipeline to constitute a circulation loop of the anoxic tank and the aerobic tank The other outlet end of the aerobic tank is connected to the secondary settling tank and the sludge concentration tank in turn.

The biological reaction tank comprises an anaerobic tank, an anoxic tank and an aerobic tank connected in series, and an outlet end of the aerobic tank is connected to the inlet end of the anoxic tank via a pipeline to constitute the anoxic tank and a circulation loop of the oxygen pool; the other outlet end of the aerobic tank is connected to the secondary settling tank and the sludge concentration tank in turn.

The biological reaction tank comprises an anaerobic tank and an oxidation ditch which are connected in sequence, and the oxidation ditch comprises an anoxic section and an aerobic section; the outlet end of the oxidation ditch is sequentially connected to the secondary settling tank and the sludge concentration tank.

The bioreactor comprises an anaerobic tank and an SBR reaction tank connected in series, and the outlet end of the SBR reaction tank is connected to the sludge concentration tank.

The biological reaction tank comprises an anaerobic tank, an anoxic tank and an MBR reaction tank connected in sequence, and an outlet end of the MBR reaction tank is connected to an inlet end of the anoxic tank to constitute the anoxic tank and the MBR reaction tank. a circulation loop; the other outlet end of the MBR reaction tank is connected to the sludge concentration tank.

The invention also discloses a method for reducing organic sludge by using a hydrodynamic cavitation reducer in a sewage treatment system, which comprises the following steps:

Step A: pretreating the high concentration organic sewage mixture through the grid and grit chamber to remove Suspended matter in an organic sewage mixture;

Step B: removing the organic pollutants in the pretreated organic sewage mixture by the biological treatment method of the biological reaction pool, utilizing the metabolism of the microorganisms, and concentrating the biologically treated effluent through the sludge concentration tank to reduce The water content of the sludge in the effluent;

Step C: After the sludge mixture treated in step B enters the first cavitation of the hydrodynamic cavitation reducer, a high-speed jet is generated to impinge on the crushing baffle facing the first cavitation, and the sewage is stained. The large granular sludge floc in the mud mixture is broken, which causes the pressure of the mixed liquid in the first-stage cavitation chamber of the hydrodynamic cavitation mud reducer to further increase; the sludge mixture after the first cavitation enters the hydrodynamic cavitation The second cavitation of the mud reduction machine generates dissolved air cavitation under the joint action of the dissolved gas chamber and the jet confinement in the second-stage cavitation device; the sludge mixture after the second cavitation is discharged through the secondary diffusion pipe ;

Step D: The excess sludge treated in step C is returned to the biological reaction tank and further subjected to biological treatment to further reduce the amount of organic sludge discharged.

The method step C further includes: the liquid mixture to be treated containing the sludge is subjected to two-stage cavitation treatment of the first-stage cavitation device and the second-stage cavitation device, and then sequentially enters the downstream third-stage cavitation device. The third cavitation in the third cavitation and the fourth cavitation in the fourth-stage cavitation unit are subjected to three-stage and four-stage cavitation treatment, and finally discharged through the outlet pipe.

The step B is specifically:

B1: the pretreated organic sewage mixture and the sewage mixture refluxed from the aerobic tank enter the anoxic tank for denitrification treatment;

B2: the organic sewage mixture treated by the anoxic tank enters the aerobic tank to remove BOD in the organic sewage, realize the nitrification of ammonia nitrogen and the absorption of phosphorus; and return some of the sewage mixture after the aerobic treatment Into the anoxic pool;

Or the step B is specifically:

B0: the pretreated organic sewage mixture enters the anaerobic tank, wherein the organic sewage mixture releases phosphorus in the anaerobic tank, and at the same time, a part of the organic matter is subjected to ammoniation treatment and then enters the anoxic tank;

B1: the pretreated organic sewage mixture and the sewage mixture refluxed from the aerobic tank enter the anoxic tank for denitrification treatment;

B2: the organic sewage mixture treated by the anoxic tank enters the aerobic tank to remove BOD in the organic sewage, realize the nitrification of ammonia nitrogen and the absorption of phosphorus; and return some of the sewage mixture after the aerobic treatment Into the anoxic pool;

Or the step B is specifically: the pretreated organic sewage mixture enters the anaerobic tank, and the phosphorus accumulating bacteria in the organic sewage in the anaerobic tank releases phosphorus, and at the same time, some organic substances are subjected to ammoniation treatment and then enter In the oxygen channel; organic sewage is treated in the oxidation ditch to remove BOD in the organic sewage, to achieve nitrification of ammonia nitrogen and absorption of phosphorus;

Or the step B is specifically: the pretreated organic sewage mixture enters the anaerobic tank, and the organic sewage releases phosphorus in the anaerobic tank, and at the same time, some organic substances are subjected to ammoniation treatment and then enter the SBR reaction tank. The microorganisms in the SBR reaction tank use the organic matter in the organic sewage for metabolism, and convert the organic pollutants into CO2 and H2O inorganic substances;

Or step B specifically includes the following steps:

B01: the pretreated organic sewage mixture enters the anaerobic tank, wherein the phosphorus accumulating bacteria in the organic sewage release phosphorus in the anaerobic tank, and at the same time, some organic substances are ammoniated and decomposed into the anoxic tank. ;

B02: the pretreated organic sewage mixture and the sewage mixture returning from the MBR reaction tank enter the anoxic tank for denitrification treatment;

B03: The organic sewage mixture treated by the anoxic tank enters the MBR reaction tank to degrade the organic matter in the organic sewage; and the part of the sewage mixture treated by the MBR reaction tank is returned to the anoxic tank. .

Compared with the prior art, the invention can effectively reduce the amount of excess sludge after biochemical treatment of the organic sewage mixture and improve the biological treatment effect.

DRAWINGS

1 is a schematic structural view of a hydrodynamic cavitation reducing machine used in the present invention;

2 is a process flow diagram of the A/O biochemical treatment process of the system of the present invention;

Figure 3 is a process flow diagram of the A ² /O biochemical treatment process of the system of the present invention;

4 is a process flow diagram of a biochemical treatment process of an oxidation ditch in the system of the present invention;

Figure 5 is a process flow diagram of the SBR biochemical treatment process of the system of the present invention;

Figure 6 is a process flow diagram of the MBR biochemical treatment process of the system of the present invention;

Figure 7 is a flow chart of the method of the present invention.

detailed description

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein It is intended to be merely illustrative of the invention and is not intended to limit the invention.

The invention effectively realizes a sewage treatment system for reducing organic sludge, comprising a grid, a grit chamber, a biological reaction tank and a sludge concentration tank which are sequentially connected. A hydraulic cavitation sludge reducer is connected between the outlet end of the sludge concentration tank and the inlet of the biological reaction tank to form a sewage circulation system, and the inlet end of the hydrodynamic cavitation sludge reducer is connected to the outlet end of the sludge concentration tank, and the hydraulic power is The outlet end of the cavitation mud reducer is connected to the inlet end of the bioreactor through a pipeline.

As shown in FIG. 1, the hydrodynamic cavitation reducer used in the present invention includes at least two stages of cavitation devices connected in series with each other; the first stage cavitation device 100 includes a first stage placed in the cavitation chamber 101. a cavitation 103 and a pulverizing baffle 102 facing the outlet of the first cavitation 103; the second stage cavitation device 20 includes a second cavitation 21, a jet confinement 25 and a secondary diffusion pipe sequentially connected 26. The jet restriction body 25 is located in the dissolved gas chamber 23, and the dissolved gas chamber 23 is provided with a dissolved gas regulating mechanism.

As shown in FIG. 1, the first stage cavitation apparatus 100 includes a first-stage cavitation chamber 101, a first cavitation 103 disposed in the first-stage cavitation chamber 101, and a first cavitation chamber 101. And the pulverizing baffle 102 exiting the first cavitation 103. The first cavitation 103 is specifically a first shrink nozzle, the first shrink nozzle is horizontally mounted on the casing of the first stage cavitation device 100, and the outlet end thereof extends into the first stage. The cavitation device 100 housing and the first support capsule 104 enclose a first-stage cavitation chamber 101. The pulverizing baffle 102 is vertically fixed to the rear side of the first support sealing plate 104. Preferably, the pulverizing baffle 102 is a curved pulverizing baffle that is adapted to the injection angle of the first contraction nozzle outlet. When the mixed liquid containing the sludge enters the first cavitation 103, a high-speed jet is generated and hits the crushing baffle 102, and the crushing baffle 102 is struck by the impact, so that the sludge flocs in the mixture are first destroyed, so that the subsequent cavitation energy can be easily The sludge cells acted adequately to increase the efficiency of cavitation on the cell wall breaking and to enhance the primary cavitation effect.

The second cavitation 21 is a second shrink nozzle disposed vertically downward. To enhance cavitation efficiency, preferably, the second cavitation 21 may be disposed in the heating chamber 22, the second The outer wall surface of the shrink nozzle, the first support sealing plate 104, the outer casing of the second stage cavitation unit 20 and the first support plate 223 are formed to form the heating chamber 22, and the heating chamber 22 is provided with a heating ring 221 on the wall surface. Preferably, the heating coil 221 is a stainless steel mica heating coil. The heating ring 221 can meet the requirements of the local water temperature working condition on the cavitation and enhance the cavitation efficiency. The wall surface of the heating chamber 22 is provided with a heat shield 222. The heating chamber 22 is an optional device, and the cavitation effect can be achieved when the heating chamber 22 is not provided. However, after the heating chamber 22 is increased, the efficiency of cavitation can be improved. A second support plate 24 is further disposed between the secondary diffusion tube 26 and the outer casing of the second stage cavitation device 20, the first support plate 223 and the second support plate 24 and a vertical wall connecting the two support plates Surrounding to form the dissolved gas chamber 23. Said The dissolved gas regulating mechanism is configured to satisfy the requirement of the jet dissolved air cavitation in the second-stage cavitation device 20 for the intake air amount, and specifically includes an intake pipe 273 communicating with the dissolved gas chamber 23, and is mounted on the intake pipe 273 The air flow meter 272 and the air regulating valve 271 disposed at the inlet of the intake pipe 273. An outlet of the second cavitation 20 extends into the dissolved gas chamber 23, and a jet restriction body 25 is further disposed at the outlet of the second cavitation 20 for smoothing the jet and generating eddy current cavitation. The vertical section of the jet restriction body 25 is substantially "V" shaped. The outlet of the jet restriction body 25 interfaces with the inlet of the secondary diffusion pipe 26.

After the slurry to be treated enters the first cavitation 103, a high-speed jet impinges on the pulverizing baffle 102 to break up the large granular sludge flocs in the mixed liquid, and then enters the second The cavitation 21, the mixed liquid generates dissolved air cavitation in the second cavitation 21, and the second cavitation mixed liquid is discharged through the secondary diffusion pipe 26.

The hydrodynamic cavitation reducer used in the present invention further includes a third stage cavitation unit 30 and a fourth stage cavitation unit 40. The tertiary cavitation device 30 includes a third cavitation 32 and a tertiary diffusion tube 33 coupled thereto. The third cavitation 32 is specifically a third contraction nozzle disposed vertically downward. The four stage cavitation unit 40 includes a fourth cavitation 42. The fourth cavitation 42 is specifically a fourth shrink nozzle disposed vertically downward, and the fourth shrink nozzle is further provided with a plurality of cavitation nozzles. The fourth cavitation 42 projects downward into the fourth cavitation chamber 43. The outlet of the four-stage cavitation unit 40 is further provided with an outlet pipe 45 and a drain valve 44.

The second stage cavitation unit 20, the third stage cavitation unit 30 and the fourth stage cavitation unit 40 are vertically arranged from top to bottom; the first stage cavitation unit 100 is horizontally arranged and located at the second stage cavitation unit Above 20.

The first stage cavitation device 100 is connected to the second stage cavitation device 20 by a first support sealing plate 104; the second stage cavitation device 20 is cavitation with the third stage by a second support sealing plate 31 The device 30 is connected; the third stage cavitation device 30 is connected to the fourth stage cavitation unit 40 via a third support closure 41.

The liquid mixture to be treated containing sludge is subjected to two-stage cavitation treatment of the first-stage cavitation device 100 and the second-stage cavitation device 20, and then enters the third cavitation in the third-stage cavitation device 30 in sequence. The fourth cavitation 42 in the unit 32 and the fourth stage cavitation unit 40 performs three-stage and four-stage cavitation processing, and is finally discharged through the outlet pipe 45. The bottom of the hydrodynamic cavitation reducer used in the present invention is further provided with a support 46.

As shown in FIG. 2, the system of the present invention adopts a process flow chart of an A/O biochemical treatment process, wherein the biological reaction tank comprises an anoxic tank and an aerobic tank connected in sequence, and an outlet end of the aerobic tank is connected by a pipeline. The inlet end of the anoxic tank constitutes a circulation loop of the anoxic tank and the aerobic tank; the aerobic tank The other outlet end is connected to the secondary settling tank and the sludge thickening tank in turn. The outlet end of the sewage concentrating tank is connected to the inlet end of the hydraulic cavitation mud reducer, and the outlet end of the hydraulic cavitation mud reducer is connected to the inlet end of the anoxic tank.

As shown in FIG. 3, the system of the present invention adopts a process flow chart of an A ² /O biochemical treatment process, and the biological reaction pool includes an anaerobic tank, an anoxic tank and an aerobic tank which are sequentially connected, and an outlet of the aerobic tank The inlet end of the anoxic tank connected to the end of the pipeline constitutes a circulation loop including the anoxic tank and the aerobic tank; and the other outlet end of the aerobic tank is connected to the secondary settling tank and the sludge concentration tank in turn. The outlet end of the sludge concentration tank is connected to the inlet end of the hydraulic cavitation mud reducer, and the outlet end of the hydraulic cavitation mud reducer is connected to the inlet end of the anaerobic tank.

As shown in FIG. 4, the system of the present invention adopts a process flow chart of an oxidation ditch biochemical treatment process, wherein the bioreactor comprises an anaerobic tank and an oxidation ditch which are sequentially connected, and the oxidation ditch includes an anoxic section and an aerobic section; The outlet end of the ditch is connected to the secondary settling tank and the sludge thickening tank in sequence. The outlet end of the sludge concentration tank is connected to the inlet end of the hydraulic cavitation mud reducer, and the outlet end of the hydraulic cavitation mud reducer is connected to the inlet end of the anaerobic tank.

As shown in FIG. 5, in the process flow chart of the SBR biochemical treatment process of the system of the present invention, the biological reaction tank comprises an anaerobic tank and an SBR reaction tank connected in sequence, and the outlet end of the SBR reaction tank is connected to the sludge concentration tank. The outlet end of the sludge concentration tank is connected to the inlet end of the hydraulic cavitation mud reducer, and the outlet end of the hydraulic cavitation mud reducer is connected to the inlet end of the anaerobic tank.

As shown in FIG. 6 , the system of the present invention adopts a process flow chart of an MBR biochemical treatment process, and the biological reaction pool includes an anaerobic tank, an anoxic tank and an MBR reaction tank connected in sequence, and an outlet end connection of the MBR reaction tank. The inlet end of the anoxic tank constitutes a circulation loop including the anoxic tank and the MBR reaction tank; the other outlet end of the MBR reaction tank is connected to the sludge concentration tank. The outlet end of the sludge concentration tank is connected to the inlet end of the hydraulic cavitation mud reducer, and the outlet end of the hydraulic cavitation mud reducer is connected to the inlet end of the anaerobic tank.

As shown in Figure 7, the method of the present invention comprises the following steps:

Step A: Pretreating the high concentration organic sewage mixture to remove floating matter and suspended matter in the organic sewage mixture. In step A, the high concentration organic sewage mixture is pretreated by a grid and a grit chamber which are sequentially connected. The grid is composed of a group or array of parallel metal grid bars, plastic gears or metal screens, frames and related devices, and is installed obliquely at the front end of the sewage channel or sewage treatment plant to intercept the coarser organic wastewater mixture. Floating objects and suspended solids, such as: fiber, broken skin, hair, peel, vegetables, wood chips, cloth strips, plastic products, etc., reduce the scum generated by subsequent treatment, and ensure the normal operation of sewage treatment facilities. The sedimentation tank is used to remove inorganic particles that are easy to settle in the sewage, or suspended solids in the water, and also remove a part of the organic matter in a suspended state.

Step B: removing the organic pollutants in the pretreated organic sewage mixture by the biological treatment method of the biological reaction pool, utilizing the metabolism of the microorganisms, and concentrating the biologically treated effluent to reduce the sludge in the effluent Water content

Step C: After the sludge mixture treated in the second step enters the first cavitation 103 of the hydrodynamic cavitation reducer, a high-speed jet is generated to impinge on the pulverizing baffle 102 facing the first cavitation 103. , the large granular sludge flocs in the sludge mixture are broken, and the pressure of the mixed liquid in the first-stage cavitation chamber 101 of the hydrodynamic cavitation reducer is further increased; the sludge mixture after the first-stage cavitation The second cavitation 21 of the hydrodynamic cavitation reducer enters, and the dissolved air cavitation is generated by the combined action of the dissolved gas chamber 23 and the jet confinement body 25 in the second-stage cavitation device 20; The mud mixture is discharged through the secondary diffusion pipe 26. Preferably, the sludge mixture after the first cavitation in step C enters the second cavitation 21 of the hydrodynamic cavitation reducer, the heating coil 221 and the dissolved gas chamber 23 in the second-stage cavitation device 20 and The jet restriction body 25 acts to generate dissolved cavitation.

The step C further includes: the liquid mixture to be treated containing the sludge passes through the two-stage cavitation treatment of the first-stage cavitation device 100 and the second-stage cavitation device 20, and then sequentially enters the downstream third-stage cavitation device. The third cavitation 32 in 30 and the fourth cavitation 42 in the fourth stage cavitation unit 40 perform three-stage and four-stage cavitation processing, and are finally discharged through the outlet pipe 45.

Step D: The remaining sludge treated in the third step is returned to the biological reaction tank and biologically treated again to reduce the amount of organic sludge discharged.

As shown in FIG. 2, in the process flow chart of the A/O biochemical treatment process of the present invention, the step B is specifically:

B1: the pretreated organic sewage mixture and the mixed liquid refluxed from the aerobic tank enter the anoxic tank for denitrification treatment;

B2: the organic sewage mixture treated by the anoxic tank enters the aerobic tank to remove the BOD in the organic sewage mixture, and realize the nitrification of ammonia nitrogen and the absorption of phosphorus; and the partial sewage mixture after the aerobic treatment is refluxed To the anoxic pool. The BOD is specifically a biological oxygen demand.

The sewage mixture passing through the aerobic tank enters the secondary settling tank to separate the muddy water, and the suspended solids are separated from the water. After the separation, the supernatant liquid is discharged as treated purified water, and the separated part of the sludge mixture enters. The sludge concentration tank is concentrated and then introduced into the hydrodynamic cavitation mud reduction machine for cavitation treatment, and the excess sludge treated by the hydrodynamic cavitation sludge reducer is returned to the anoxic tank to continue biological treatment. .

As shown in FIG. 3, the step B in the process flow chart of the A ² /O biochemical treatment process of the present invention is specifically as follows:

B0: the pretreated organic sewage mixture enters the anaerobic tank, wherein the organic sewage mixture releases phosphorus in the anaerobic tank, and at the same time, a part of the organic matter is subjected to ammoniation treatment and then enters the anoxic tank;

B1: the pretreated organic sewage mixture and the mixed liquid refluxed from the aerobic tank enter the anoxic tank for denitrification treatment;

B2: the organic sewage mixture treated by the anoxic tank enters the aerobic tank to remove the BOD in the organic sewage mixture, and realize the nitrification of ammonia nitrogen and the absorption of phosphorus; and the partial sewage mixture after the aerobic treatment is refluxed To the anoxic pool.

The sewage mixture passing through the aerobic tank enters the secondary settling tank to separate the muddy water, and the suspended solids are separated from the water. After the separation, the supernatant liquid is discharged as treated purified water, and the separated part of the sludge mixture enters. The sludge concentration tank is concentrated and then introduced into the hydrodynamic cavitation mud reduction machine for cavitation treatment, and the excess sludge treated by the hydrodynamic cavitation sludge reducer is returned to the anoxic tank to continue biological treatment. .

As shown in FIG. 4, in the process flow chart of the oxidation ditch biochemical treatment process of the system of the present invention, the step B is specifically: the pretreated organic sewage mixture enters the anaerobic tank, and the organic sewage in the anaerobic tank The phosphorus accumulating bacteria in the mixture release phosphorus, and at the same time, some organic substances are subjected to ammoniation treatment and then enter the oxygen ditch; the organic sewage is treated in the oxidation ditch to realize nitrification of ammonia nitrogen and absorption of phosphorus.

The sewage mixture passing through the oxidation ditch enters the secondary settling tank to separate the muddy water, and the suspended solids are separated from the water. After the separation, the supernatant liquid is discharged as treated purified water, and the separated part of the sludge mixture enters the After being concentrated in the sludge concentration tank, it is introduced into the hydrodynamic cavitation sludge reducer for cavitation treatment, and the excess sludge treated by the hydrodynamic cavitation sludge reducer is returned to the anaerobic tank to continue biological treatment.

As shown in FIG. 5, in the process flow chart of the SBR biochemical treatment process, the step B specifically includes: the pretreated organic sewage mixture enters the anaerobic tank, and the organic sewage releases phosphorus in the anaerobic tank. At the same time, some organic substances are ammoniated and then enter the SBR reaction tank. The microorganisms in the SBR reaction tank use the organic matter in the organic sewage to carry out metabolism, and convert the organic pollutants into CO ₂ and H ₂ O inorganic substances.

The supernatant liquid treated by the SBR reaction tank is discharged as treated purified water, and the treated partial sludge mixture enters the sludge concentration tank for concentration, and then enters the hydraulic cavitation sludge reducer for emptying. After the treatment, the excess sludge treated by the hydrodynamic cavitation reducer is returned to the anaerobic Biological processing continues in the pool.

As shown in FIG. 6, in the process flow diagram of the MBR biochemical treatment process, the step B specifically includes the following steps:

B01: the pretreated organic sewage mixture enters the anaerobic tank, wherein the phosphorus accumulating bacteria in the organic sewage release phosphorus in the anaerobic tank, and at the same time, some organic substances are ammoniated and decomposed into the anoxic tank. ;

B02: the pretreated organic sewage mixture and the mixed liquid refluxed in the MBR reaction tank enter the anoxic tank for denitrification treatment;

B03: The organic sewage mixture treated by the anoxic tank enters the MBR reaction tank to degrade the organic matter in the organic sewage mixture; a part of the mixed liquid treated by the MBR reaction tank is returned to the anoxic tank.

The supernatant liquid treated by the MBR reaction tank is discharged as treated purified water, and the treated partial sludge mixture enters the sludge concentration tank for concentration, and then enters the hydraulic cavitation sludge reducer for emptying. After the treatment, the excess sludge treated by the hydrodynamic cavitation reducer is returned to the anaerobic tank to continue biological treatment.

In the method of the present invention, the sewage mixture treated by the hydrodynamic cavitation reducer undergoes a cavitation step of the third stage cavitation unit 30 and the fourth stage cavitation unit 40 after two stages of cavitation treatment. Through the continuous action of the above four-stage cavitation, the cavitation effect is enhanced, the sludge flocs are fragmented and the refractory organic matter is directly decomposed into CO ₂ and H ₂ O, and the refractory organic matter is broken into small molecules. The chain is then oxidized to fatty acids, thereby increasing the biodegradability of the sewage organics. It creates favorable conditions for the subsequent biochemical reaction, so that the organic matter is more easily decomposed by biochemical action, and the organic sludge is reduced. After using this method, the sludge output can be reduced by 60-70%.

The hydraulic cavitation sludge reducing machine adopted by the invention is a comprehensive hydraulic cavitation practical device. The working principle is as follows: the sludge mixture which provides a certain flow and pressure by the non-blocking sewage pump enters the hydrodynamic cavitation mud reducer, and produces a continuous action of four-stage cavitation, which strengthens the treatment degree of the sludge. The non-blocking sewage pump enables the sludge mixture to enter the first-stage cavitation at high speed, and realizes the sludge mixing under the combined action of the cavitation cavitation of the first-stage cavitation and the high-speed water flow at the outlet of the first-stage cavitation. The first pretreatment of the liquid to achieve the flocculation of large granular sludge flocs and provide sufficient pressure and flow ratio for the second stage cavitation effect. Next, the continuous three-stage cavitation more fully processes the first-stage cavitation-pretreated muddy water, thereby improving the one-time treatment efficiency of the mud-reducing machine.

The coupling of the above four-stage cavitation effect causes the organic matter in the sludge water to be fully oxidized and decomposed. At the same time, the cavitation is accompanied by a micro-jet with a strong shock wave, and is continuously performed tens of thousands of times per second. When used, it brings about high-efficiency mechanical chopping effect, and produces a highly chemically active free radical -OH, which is then oxidized with organic contaminants in the solution to oxidize and decompose organic pollutants in the mixture into low molecular weight substances, shock waves. And the powerful hydraulic shear force generated by the high-speed micro-jet in the mixed liquid effectively destroys the sludge structure, breaks the carbon bond on the main chain of the macromolecule, transforms into a short-chain bottom molecular organic substance, and causes the intracellular solute to flow out, and Further broken down.

The effect of the method of the invention is as follows:

The method of the invention is applied in a sewage treatment plant that processes 100,000 tons in Shenzhen one day. In the first five months of 2015, the sewage treatment plant treated 8.28 tons of wet mud cake with a moisture content of 80% per ton of sewage before the method of the invention was obtained, that is, 82.8 tons/day per day. After adopting the method of the invention, the wet mud cake which produces 80% moisture content per 10,000 tons of sewage in June is reduced to 7.35 tons, that is, 73.5 tons/day is produced every day; in the first half of July, the moisture content per 10,000 tons of sewage is 80%. The wet mud cake is reduced to 6.08 tons, which is 60.8 tons/day per day; in the second half of July, the wet mud cake with 80% water content per 10,000 tons of sewage is reduced to 5.09 tons, ie 50.9 tons/day per day; This technology can achieve significant mud reduction effects.

The actual application effect is shown in Table 1.

Table 1. Application effect of a sewage treatment plant with a capacity of 100,000 tons in Shenzhen one day

The above description is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalents, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims (10)

1. A sewage treatment system for effectively realizing reduction of organic sludge, comprising a grid, a grit chamber, a biological reaction tank and a sludge concentration tank which are sequentially connected, and is characterized in that:

   a hydraulic cavitation sludge reducer is connected between the outlet end of the sludge thickening tank and the inlet of the biological reaction tank to form a sewage circulation system, and the inlet end of the hydraulic cavitation sludge reducer is connected to the sludge concentration tank. At the outlet end, the outlet end of the hydrodynamic cavitation reducer is connected to the inlet end of the biological reaction tank via a pipeline;

   The hydrodynamic cavitation mud reducer comprises at least two stages of cavitation devices connected in series;

   The first stage cavitation device (100) includes a first cavitation (103) disposed within the primary cavitation chamber (101) and a comminution baffle (102) opposite the outlet of the first cavitation (103) );

   The second stage cavitation device (20) includes a second cavitation (21), a jet confinement (25) and a secondary diffusion tube (26) that are sequentially connected, the jet confinement (25) being located in the dissolved gas chamber ( 23) The dissolved gas chamber (23) is provided with a dissolved gas regulating mechanism.
2. A sewage treatment system for effectively realizing organic sludge reduction according to claim 1, wherein said hydrodynamic cavitation sludge reducer further comprises a third stage cavitation unit (30) and a fourth stage cavitation unit ( 40); the second stage cavitation device (20), the third stage cavitation device (30) and the fourth stage cavitation device (40) are vertically arranged from top to bottom; the first stage cavitation device (100) arranged horizontally and above the second stage cavitation device (20);

   The first stage cavitation device (100) is coupled to the second stage cavitation device (20) by a first support closure (104); the second stage cavitation device (20) is passed through a second support seal a plate (31) is coupled to the third stage cavitation device (30); the third stage cavitation device (30) passes through a third support seal plate (41) and the fourth stage cavitation device (40) connection.
3. The sewage treatment system for effectively realizing organic sludge reduction according to any one of claims 1 to 2, wherein the biological reaction tank comprises an anoxic tank and an aerobic tank connected in sequence, the aerobic tank An outlet end of the anoxic tank is connected to the outlet end of the anoxic tank to form a circulation loop of the anoxic tank and the aerobic tank; the other outlet end of the aerobic tank is connected to the secondary settling tank and the sludge concentration tank in turn.
4. The sewage treatment system for effectively realizing organic sludge reduction according to any one of claims 1 to 2, wherein the biological reaction tank comprises an anaerobic tank, an anoxic tank and an aerobic tank connected in sequence; An outlet end of the aerobic tank is connected to the inlet end of the anoxic tank via a pipeline to form a circulation loop including the anoxic tank and the aerobic tank; the other outlet end of the aerobic tank is connected to the second settling tank in turn Said Sludge concentration tank.
5. The sewage treatment system for effectively realizing organic sludge reduction according to any one of claims 1 to 2, wherein the biological reaction tank comprises an anaerobic tank and an oxidation ditch which are sequentially connected, and the oxidation ditch comprises anoxic acid. a section and an aerobic section; the outlet end of the oxidation ditch is sequentially connected to the secondary settling tank and the sludge concentration tank.
6. The sewage treatment system for effectively realizing organic sludge reduction according to any one of claims 1 to 2, wherein the biological reaction tank comprises an anaerobic tank and an SBR reaction tank connected in series, and the SBR reaction tank The outlet end is connected to the sludge concentration tank.
7. The sewage treatment system for effectively realizing the reduction of organic sludge according to any one of claims 1 to 2, wherein the biological reaction tank comprises an anaerobic tank, an anoxic tank and an MBR reaction tank which are sequentially connected. An outlet end of the MBR reaction tank is connected to the inlet end of the anoxic tank to constitute a circulation loop including the anoxic tank and the MBR reaction tank; and the other outlet end of the MBR reaction tank is connected to the sludge concentration tank.
8. A method for reducing organic sludge by using a hydrodynamic cavitation reducer in a sewage treatment system, comprising the steps of:

   Step A: pretreating the high concentration organic sewage mixture through the grid and the grit chamber to remove the suspended matter in the organic sewage mixture;

   Step B: removing the organic pollutants in the pretreated organic sewage mixture by the biological treatment method of the biological reaction pool, utilizing the metabolism of the microorganisms, and concentrating the biologically treated effluent through the sludge concentration tank to reduce The water content of the sludge in the effluent;

   Step C: After the sludge mixture treated in step B enters the first cavitation (103) of the hydrodynamic cavitation reducer, a high-speed jet impinges on the smash which is opposite to the first cavitation (103). The baffle (102) crushes the large granular sludge flocs in the sludge mixture, which causes the pressure of the mixed liquid in the first-stage cavitation chamber (101) of the hydrodynamic cavitation mud reducer to further increase; The cavitation sludge mixture enters the second cavitation (21) of the hydrodynamic cavitation reducer, and the dissolved gas chamber (23) and the jet confinement (25) in the second stage cavitation unit (20) The dissolved air cavitation is generated by the combined action; the sludge mixture after the second cavitation is discharged through the secondary diffusion pipe (26);

   Step D: The excess sludge treated in step C is returned to the biological reaction tank and further subjected to biological treatment to further reduce the amount of organic sludge discharged.
9. A method for reducing organic sludge by using a hydrodynamic cavitation reducer in a sewage treatment system according to claim 8, wherein:

   The method step C further comprises: the mixture to be treated containing the sludge passes through the first stage cavitation device After the two-stage cavitation treatment of (100) and the second-stage cavitation device (20), the third cavitation (32) and the fourth-stage empty in the downstream third-stage cavitation device (30) are sequentially entered. The fourth cavitation (42) in the chemical device (40) performs three-stage and four-stage cavitation treatment, and is finally discharged through the outlet pipe (45).
10. A method for reducing organic sludge by using a hydrodynamic cavitation reducer in a sewage treatment system according to any one of claims 8 to 9, characterized in that:

    The step B is specifically:

    B1: the pretreated organic sewage mixture and the sewage mixture refluxed from the aerobic tank enter the anoxic tank for denitrification treatment;

    B2: the organic sewage mixture treated by the anoxic tank enters the aerobic tank to remove BOD in the organic sewage, realize the nitrification of ammonia nitrogen and the absorption of phosphorus; and return some of the sewage mixture after the aerobic treatment Into the anoxic pool;

    Or the step B is specifically:

    B0: the pretreated organic sewage mixture enters the anaerobic tank, wherein the organic sewage mixture releases phosphorus in the anaerobic tank, and at the same time, a part of the organic matter is subjected to ammoniation treatment and then enters the anoxic tank;

    B1: the pretreated organic sewage mixture and the sewage mixture refluxed from the aerobic tank enter the anoxic tank for denitrification treatment;

    B2: the organic sewage mixture treated by the anoxic tank enters the aerobic tank to remove BOD in the organic sewage, realize the nitrification of ammonia nitrogen and the absorption of phosphorus; and return some of the sewage mixture after the aerobic treatment Into the anoxic pool;

    Or the step B is specifically: the pretreated organic sewage mixture enters the anaerobic tank, and the phosphorus accumulating bacteria in the organic sewage in the anaerobic tank releases phosphorus, and at the same time, some organic substances are subjected to ammoniation treatment and then enter In the oxygen channel; organic sewage is treated in the oxidation ditch to remove BOD in the organic sewage, to achieve nitrification of ammonia nitrogen and absorption of phosphorus;

    Or the step B is specifically: the pretreated organic sewage mixture enters the anaerobic tank, and the organic sewage releases phosphorus in the anaerobic tank, and at the same time, some organic substances are subjected to ammoniation treatment and then enter the SBR reaction tank. The microorganisms in the SBR reaction tank utilize the organic matter in the organic sewage for metabolism, and convert the organic pollutants into CO ₂ and H ₂ O inorganic substances;

    Or step B specifically includes the following steps:

    B01: the pretreated organic sewage mixture enters the anaerobic tank, wherein the phosphorus accumulating bacteria in the organic sewage release phosphorus in the anaerobic tank, and at the same time, a part of the organic matter is ammoniated and decomposed into the anoxic group. In the pool;

    B02: the pretreated organic sewage mixture and the sewage mixture returning from the MBR reaction tank enter the anoxic tank for denitrification treatment;

    B03: The organic sewage mixture treated by the anoxic tank enters the MBR reaction tank to degrade the organic matter in the organic sewage; and the part of the sewage mixture treated by the MBR reaction tank is returned to the anoxic tank.

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