CN113880367A

CN113880367A - High-efficiency aquaculture tail water solid particulate matter removing system and tail water purifying method

Info

Publication number: CN113880367A
Application number: CN202111293621.XA
Authority: CN
Inventors: 程果锋; 刘兴国; 王婕; 陶祯; 唐荣; 葛鹏彪
Original assignee: Suzhou Lexing Ecological Environmental Protection Technology Co ltd; Fishery Machinery and Instrument Research Institute of CAFS
Current assignee: Suzhou Lexing Ecological Environmental Protection Technology Co ltd; Fishery Machinery and Instrument Research Institute of CAFS
Priority date: 2021-11-03
Filing date: 2021-11-03
Publication date: 2022-01-04

Abstract

The invention provides an aquaculture tail water solid particle efficient removal system and a tail water purification method. The tail water firstly flows upwards and downwards in a circuitous way through the two retaining walls, so that partial particles are separated from the water body. And then, the water subjected to primary sedimentation continuously enters a backwashing filter system and flows from bottom to top in the backwashing filter system, the water is discharged after being filtered by the filter mechanism, and the backwashing mechanism conveys high-pressure gas or high-pressure water into the filter mechanism, so that particles enriched on the outer surface of the filter screen fall off and are deposited in clusters, and the water is convenient for people to intensively clean. The invention can well treat the tail water and then discharge the tail water, realizes ecological breeding and is beneficial to sustainable development.

Description

High-efficiency aquaculture tail water solid particulate matter removing system and tail water purifying method

Technical Field

The invention relates to ecological breeding of rice and shrimp fields, in particular to an efficient aquaculture tail water solid particulate matter removing system and a tail water purifying method.

Background

The phenomenon that aquaculture tail water is directly discharged, the aquaculture tail water is directly discharged in the water changing and harvesting periods, and the environment is polluted exists in the existing aquaculture industry, and the sustainable development of the industry is influenced by the site of tail water pollution nowadays when the environmental protection is increasingly emphasized.

At present, treatment of aquaculture tail water is a hotspot and difficulty of the industry. Research and actual measurement show that nitrogen and phosphorus attached to the solid suspended matters account for 42-67% of nitrogen and phosphorus in the whole water body, and the suspended matters are effectively removed, so that the method has an important effect on reducing nitrogen and phosphorus pollution of the water body. The existing three-pond two-dam process for treating the tail water of pond culture and the composite artificial wetland purification process are all composed of a sedimentation tank, an aeration tank, an ecological tank and a filtering dam, wherein the tail water purification area accounts for 8-15% of the whole pond area, and the tail water purification process is resisted by farmers in popularization due to large occupied area. Wherein the area of the sedimentation tank for removing the particle sediment accounts for 40 percent of the whole tail water purification area, which limits the popularization of the process. The research on the efficient removal method of the solid particles in the tail water makes it imperative to reduce the occupied area of the settling zone. The research shows that solid particles with the particle size larger than 100um only account for 7-10% of all the particles, the particle size of 50-100um approximately accounts for 12-15% of all the solid particles, the rest particles with the particle size smaller than or equal to 50um account for 60-70% of the total amount of the solid particles, most of fine particles are in a suspended state which is not easy to settle in the water due to the fact that the particle size is too small and the density is slightly larger than that of water, the problems of low efficiency, large occupied area, long time and the like due to the fact that precipitation is only relied on are solved, and the problems of long time, secondary release and the like of nitrogen and phosphorus attached to the solid particles are also solved. Therefore, improving the removal of solid particles is an urgent core problem to be solved by the tail water of the current aquaculture.

Disclosure of Invention

The invention provides an aquaculture tail water solid particulate matter efficient removal system, which is arranged at a rice and shrimp field water outlet and used for purifying tail water discharged from a rice and shrimp field, and is provided with a retaining wall, a backwashing filter system and a sewage suction system;

the retaining wall is positioned and comprises a plurality of baffle plates which are vertical in the water flow direction, flowing tail water sequentially flows in an up-and-down circuitous mode in the vertical direction through the baffle plates and then enters the backwashing filtering system, and a first sludge collecting groove which is sunken downwards is formed in the bottom sludge surface between every two adjacent baffle plates;

the backwashing filter system comprises a filter mechanism and a backwashing mechanism, the filter mechanism comprises a filter tank, a mud surface at the bottom of the filter tank is provided with a second sewage collecting groove which is sunken downwards, one side of the filter tank far away from the retaining wall is provided with a plurality of water outlets, a plurality of filters which are horizontally distributed are arranged in the filter tank, the filters are hollow tubular mechanisms, the pipe walls of the filters are made of porous materials, the outer walls of the filters are coated with filter screens, one end of each hollow pipeline of each filter is closed, and the other end of each hollow pipeline is respectively connected with the water outlets,

the backwashing mechanism comprises a high-pressure cleaning device and a plurality of washing nozzles, the high-pressure cleaning device is connected with the washing nozzles through a hose, the washing nozzles are arranged on one side of a water outlet of the filter tank through a sliding support, and the sliding support drives the washing nozzles to move so as to be connected with the water outlet;

the sewage suction system is provided with a sewage suction pump, the sewage suction pump is connected with a plurality of sewage suction pipes, and the tail ends of the sewage suction pipes are respectively connected with the first sewage collecting groove and the second sewage collecting groove.

Further, the high-pressure cleaning device is a variable-frequency water pump or an air pump.

Furthermore, the retaining wall comprises a first retaining plate and a second retaining plate which are sequentially erected in the water flow direction;

the top of the first baffle is positioned below the liquid level of the rice and shrimp field, and the water outlet is lower than the upper surface of the first baffle;

the second baffle comprises an upper baffle wall and a lower baffle wall which are spaced from each other up and down, a water passing hole lower than the top surface of the first baffle wall is reserved between the upper baffle wall and the lower baffle wall, and the top surface of the upper baffle wall is higher than the liquid level of the rice and shrimp field.

Furthermore, the plurality of baffles are all higher than the liquid level of the rice and shrimp field, the baffles are respectively provided with water passing ports, the water passing ports are arranged in a staggered mode in the water flow direction, and the tail water can also flow in an up-and-down circuitous mode.

Further, the filter is a plastic blind ditch pipe.

A tail water purification method based on the aquaculture tail water solid particulate matter efficient removal system comprises the following steps:

the flowing tail water flows in a roundabout manner up and down through the retaining wall, and particulate matters in the tail water are preliminarily deposited on the mud surface on the front side of each baffle;

tail water primarily filtered by the retaining wall enters the backwashing filtering system, the tail water is filtered by the filter and then is discharged from the water outlet, and dirt and particulate matters in the tail water are adsorbed on the surface by the filter screen;

when the filter and the filter screen need to be cleaned, the sliding support is moved to enable the washing spray head to be connected with the water outlet, and the high-pressure cleaning device is started to convey a high-pressure medium to the inner tube of the filter to enable dirt attached to the outer surface of the filter screen to be shaken off;

and starting the sewage suction pump to suck away the particulate matters deposited in the first sewage collecting tank and the second sewage collecting tank.

Further, the high-pressure cleaning device intermittently conveys the high-pressure medium to the filter inner pipe, and the pressure of the high-pressure medium conveyed each time is higher and higher.

According to the aquaculture tail water solid particulate matter efficient removal system provided by the invention, tail water firstly flows in a vertically circuitous manner through the retaining wall, a part of particulate matters in the tail water can be deposited on mud surfaces on the front sides of the retaining walls of the retaining wall, then the primarily filtered water continuously enters the backwashing filter system, the tail water flows from bottom to top inside, the particulate matters in the tail water are adsorbed by the filter screen to play a filtering role, and finally the tail water passes through the inner pipe of the filter pipe and is discharged. When the surface of the filter screen is excessively dirty, the high-pressure cleaning device can be opened, and the high-pressure cleaning device conveys high-pressure gas or high-pressure water to the interior of the backwashing filter system to enable the dirt attached to the outer surface of the filter screen to fall off and deposit, so that the high-pressure cleaning device is convenient for people to intensively clean and prolongs the service life of the filter screen.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

FIG. 1 is a schematic view showing the distribution of the tail water purification area and the ecological purification area in the paddy field and the shrimp field;

FIG. 2 is a schematic diagram of an efficient solid particulate removal system for aquaculture tail water according to the present invention;

FIG. 3 is a view showing the internal structure of a filter mechanism in the filter chamber.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the invention.

In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The following detailed description of the preferred embodiments of the invention, however, the invention is capable of other embodiments in addition to those detailed.

Referring to fig. 1-3, the invention provides a high-efficiency purification system for solid particles in a freshwater pond, which is used for purifying water containing high-content solid particles and carrying a large amount of nitrogen, phosphorus and organic pollutants discharged from a freshwater fish culture pond 1 to a tail water purification area 3 through a drainage well 2.

Two diversion retaining walls are arranged at the front end of the purification area 3 and close to the drainage well 2, primary sedimentation is carried out, then solid particles in the water body are filtered and removed in an enhanced mode through the filtering mechanism 7, and the purified water body is discharged into the subsequent ecological purification unit 10 to be further purified and then is discharged up to the standard or recycled. Wherein, the outer filter screen of the filtering mechanism 7 filters a large amount of particles, after the water permeability is poor, the backwashing mechanism 8 is used for backwashing and removing, the filtering capability of the system is maintained, and the solid pollutants of the concentrated and deposited collection are removed in time through the sewage suction system.

As shown in fig. 2 to 3, the retaining wall comprises a first baffle 4 and a second baffle 6 which are erected in this order in the direction of water flow. The top of the first baffle 4 is positioned below the liquid level of the rice and shrimp field, and the water outlet of the backwashing filter system is lower than the upper surface of the first baffle 4. The second baffle 6 is composed of an upper baffle wall 601 and a lower baffle wall 602 which are spaced up and down, a water passing opening 603 which is lower than the top surface of the first baffle 4 is reserved between the upper baffle wall 601 and the lower baffle wall 602, and the top surface of the upper baffle wall 601 is higher than the liquid level of the rice and shrimp field.

The first baffle 4 and the second baffle 6 promote the parts with larger particle size and density in the solid particles to be quickly separated from the water body mainly by changing the water flow form, wherein the first baffle 4 is positioned at the initial section of the purification area 3 by about 5m, the wall height is not lower than 1.2m, and the wall top is positioned at the depth of about 1m below the water surface; the distance between the first baffle 4 and the second baffle 6 is generally not more than 1m, the wall top exceeds the water level of the purification area by more than 0.3m, and a water outlet 603 is arranged at the lower part; after the inlet water is blocked by the first baffle 4, part of easily-settled particles are deposited in front of the first baffle 4; the tail water after primary precipitation firstly flows upwards through the wall top of the first baffle 4 under the flow guiding action of the first baffle 4, and flows downwards through the water passing port 603 at the lower part and enters the backwashing filter system under the flow guiding action of the second baffle 6, and in the process, a downward water body is forced to horizontally change direction when passing through the water passing port 603, so that centrifugal force is generated, solid particles in the water body are separated from the water body due to the fact that the density is slightly larger than the water body and the centrifugal force is larger, and centrifugal removal is achieved; wherein the removed particulate matter accumulates in the mud face at the front side of the baffle plate, and primary removal of the particulate matter is realized.

The back-flushing filtering system consists of a filtering mechanism 7 and a back-flushing mechanism 8. The filtering mechanism 7 comprises a filtering pool 701, and the filtering pool 701 is arranged higher than the liquid level of the rice and shrimp field. A plurality of filters 702 which are horizontally arranged are fixed in the filter tank 701, the filters 702 are positioned below the water surface, a galvanized steel pipe frame is arranged outside the pipe, net film fine filter screens 703 are coated outside the outer wall of the pipe, each filter 702 penetrates into the wall grooves on the periphery of the filter tank through a four-corner support to be fixedly suspended, the distance between the filters is 0.2m, a second sewage collecting tank 7a is arranged below the filter mechanism 7, when tail water enters the filter mechanism 7 through a water passing port 603, water enters the filter mechanism from the periphery of the filter screens on the periphery of the filters 702, and the whole filter tank flows through the filter tank from a horizontal flow state. In the process, tiny solid particles are gradually intercepted outside the filter screen 703 to realize efficient removal, the removal efficiency is greatly improved compared with sedimentation, the occupied area of the original sedimentation tank can be reduced by more than 70%, the filtered water body is discharged from a water outlet 704 in the middle of the filter 702, the water outlet 704 is generally made of a PVC pipe and is embedded in the wall body of the filter tank, one end of the PVC pipe is connected with the filter screen and sealed, the other end of the PVC pipe extends out of the wall body to enter a subsequent ecological purification area 10, and standard discharge and recycling can be realized after further purification.

A backwashing mechanism: when solid particles filtered on the surface of a filter screen outside the filter module reach a certain thickness, the water body filtering resistance is increased, and the outside needs to be backwashed through a backwashing mechanism, wherein the backwashing mechanism consists of a high-pressure water pump 801, a backwashing water pipe 802, a washing nozzle 803, a sliding bracket 805 and an automatic control system, the high-pressure water pump 801 is positioned at the next stage of the filter device 7, filtered cleaning water is adopted, the backwashing water pipe 802 is connected with the high-pressure water pump 801, a group of backwashing water pipes 802 is connected behind the high-pressure water pump, the tail end of the backwashing water pipe 802 is connected with the washing nozzle 803 on the sliding bracket 805, and the washing nozzle 803 corresponds to the water outlet of each group of filter modules. When the filtering resistance of the filtering module is large and the back washing is needed, under the control of an automatic control system, the sliding support 805 is controlled to move to enable the washing nozzle 803 to be connected with the water outlet of the filtering mechanism, the high-pressure water pump 801 is started, the filtered water is pumped out instantly through the washing nozzle 803 from the back washing water pipe 802 and enters each filtering module through the water outlet of the corresponding filtering module, so that the filtering net 703 expands, the solid particles filtered on the filtering net are shaken off from the filtering net 703 under the action of expansion tension and internal water pressure and fall to the second sewage collecting tank 7a at the lower part, and the solid particles are cleaned periodically at the later stage. The back washing time is generally not more than 1min, and an instantaneous high-pressure spray washing mode is adopted to realize the washed particles.

A sewage suction system: the sewage treatment device consists of a sewage suction pump 901, a sewage collection pipe 902 and a sewage suction disc 903, and is used for regularly collecting solid particles in a first sewage collection groove 5a and a second sewage collection groove 7a and conveying the solid particles to a pond ridge or a rice field to realize timely separation of the solid particles from a water body, so that pollutants accumulated for a long time are prevented from being decomposed and deteriorated and released to the water body polluted environment again.

The tail water purification method based on the aquaculture tail water solid particulate matter efficient removal system comprises the following steps:

1) the tail water flowing out of the tail water in the rice and shrimp field flows to the drainage well through the drainage channel, the flowing tail water flows in a vertical direction in a vertically circuitous mode through the retaining wall, and partial particulate matters in the tail water are preliminarily deposited in the first sewage collecting grooves on the mud surfaces of the front sides of the baffles.

2) The tail water through the primary filtration of barricade gets into back flush filtration system, via the filter carry on filter the back by the outlet discharge, the filter screen adsorbs the dirt and the particulate matter in the tail water on the surface.

3) When the surface of the filter screen is adhered with more dirt, the high-pressure cleaning device is started, and the high-pressure cleaning device conveys a high-pressure medium to the filter, so that water in the filter flows in a reverse direction, and the dirt adhered to the outer surface of the filter screen is shaken off and deposited in the second dirt collecting groove.

4) And starting a sewage suction pump to suck away the particulate matters deposited in the first sewage collecting tank and the second sewage collecting tank.

In order to better shake off dirt on the surface of the filter screen, the high-pressure cleaning device intermittently conveys high-pressure medium (high-pressure water or high-pressure gas) into the water outlet channel, for example, high-pressure water is pumped into the backwashing filter system every 10S, and the strength is higher and higher. Generally, although the filter net is most likely to have the adhered dirt on the surface thereof removed after the first few impacts of the high-pressure medium, the dirt is less likely to be removed if the dirt is hard to be removed, and the effect of removing the dirt is not preferable if the high-pressure medium is constantly under a constant pressure. Therefore, in consideration of the above, the high-pressure cleaning device of the present invention uses the high-pressure medium with higher intermittent conveying strength, so as to remove the stubborn dirt adhered to the surface of the filter screen better, thereby improving the continuous purification effect of the backwashing filter system.

In conclusion, the invention can better filter and collect the particles in the rice and shrimp field tail water, thereby realizing ecological breeding and sustainable development.

The above description is of the preferred embodiment of the invention. It is to be understood that the invention is not limited to the particular embodiments described above, in that devices and structures not described in detail are understood to be implemented in a manner common in the art; those skilled in the art can make many possible variations and modifications to the disclosed embodiments, or modify equivalent embodiments to equivalent variations, without departing from the spirit of the invention, using the methods and techniques disclosed above. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention are still within the scope of the protection of the technical solution of the present invention, unless the contents of the technical solution of the present invention are departed.

Claims

1. An efficient removing system for solid particles in tail water of aquaculture, which is arranged at a water discharge port of a rice and shrimp field and is used for purifying the tail water discharged from the rice and shrimp field, is characterized by comprising a retaining wall, a backwashing filtering system and a sewage suction system;

2. The system for efficiently removing solid particles in aquaculture tail water according to claim 1, wherein the high-pressure cleaning device is a variable-frequency water pump or an air pump.

3. The system for efficiently removing solid particles in tail water of aquaculture as claimed in claim 1, wherein said retaining wall comprises a first baffle and a second baffle which are erected in sequence in the direction of water flow;

4. The system for efficiently removing solid particles in tail water of aquaculture as claimed in claim 1, wherein said plurality of baffles are all higher than the liquid level of said rice and shrimp field, and are respectively provided with water passing ports, and said water passing ports are arranged in a staggered manner in the direction of water flow.

5. The aquaculture tail water solid particulate matter high efficiency removal system of claim 1, wherein said filter is a plastic blind ditch tube.

6. A tail water purification method based on the aquaculture tail water solid particulate matter efficient removal system of any one of claims 1-5, wherein the method comprises the following steps:

7. The tail water purification method of claim 6, wherein the high pressure cleaning device intermittently supplies the high pressure medium to the filter inner tube, and the pressure of the high pressure medium supplied each time is increased.