CN100335423C - Water purifying method for cultivation pond - Google Patents

Abstract

The present invention discloses a water purifying method for a cultivation pond. The water purifying method comprises the following steps: cultivation waste water in the bottom layer at the center of a cultivation pond is pumped into a water bath by a water pump; suspended organic matters in the cultivation waste water are separated in the water bath; the cultivation waste water which is separated from the suspended organic matters is processed in a natural photochemical catalysis oxidation mode to return to the cultivation pond, and a water cycle is formed. The water purifying method of the present invention solves the problems that the administrative cost for water is high, and the environment is polluted existing in aquaculture, improves rationalization and biology conditions for cultivation water, and enhances the stability of cultivation hydroenvironment. The present invention is suitable for the water quality management of pond cultivation with sea and fresh water.

Description

A kind of water body purification method of aquaculture pond

technical field

The invention relates to a water body purification method of a culture pond, in particular to a circulating water body purification method of a culture pond.

Background technique

In view of the adverse effects of nitrogen, phosphorus, organic suspended solids and harmful microorganisms in the large-scale aquaculture water and drainage on the animals and the water environment, the existing solutions are mainly to change water, add chemical oxidants or Microecological agents, industrial water purification, ecosystem compensation and other methods. The measure of water change is to directly discharge part of the aquaculture wastewater regularly and then add some fresh clean water to achieve the purpose of improving the physical, chemical and biological conditions of the water body. The biggest downside to changing the water is at the expense of the environment. The biggest disadvantage of regular dosing of chemical oxidizing agents is that it destroys the ecological balance of the aquaculture water while oxidizing and detoxifying, and the operating cost is high. The biggest disadvantage of regular dosing of probiotics is that it is easy to cause large fluctuations in the physical, chemical and biological indicators of the water body, and the operating cost is high. The cost of equipment using industrial water purification treatment methods is high, and the operating cost is high. The main reasons for the ecological system compensation method are problems such as large land occupation and difficult operation and management, which affect its application to a certain extent.

Contents of the invention

The purpose of the invention is to solve the problems of high water management cost and environmental pollution in aquaculture, improve the physical, chemical and biological conditions of the aquaculture water and enhance the stability of the aquaculture water environment.

In order to achieve the above object, the invention provides a method for purifying water in a culture pond, the method comprising:

Step 1: Lift the culture wastewater at the bottom of the center of the culture pond into a water tank with a water pump;

Step 2 is to separate the suspended organic matter in the culture wastewater in the tank;

In step 3, the culture wastewater from which the suspended organic matter has been separated is subjected to natural photochemical catalytic oxidation treatment, and then returned to the culture pond to form a water cycle.

The water body purification method of the present invention utilizes the principle of shallow sedimentation to separate the suspended organic matter in the aquaculture wastewater. The depth of shallow water is generally 0.3-0.6 meters, the residence time is about 20-40 minutes, the water outlet speed is 0.7-1.5m ³ /mh, and the solid-liquid separation is carried out under the condition of near "zero" speed. The natural photochemical catalytic oxidation process generates active oxygen free radicals and aeration plays the roles of denitrification and detoxification, oxygen supplementation, algae inhibition and bacteriostasis. The natural photochemical catalytic oxidation is carried out on a slope with a slope of about 30-60 degrees. The water layer on the slope is a gravity sheet flow, the flow is greater than 1 meter, and the thickness of the water layer is less than 0.3 mm. The purified aquaculture wastewater in the shallow water tank returns to the aquaculture pond through the slope. While carrying out the water circulation, the water in the culture pond is generated by the aeration machine arranged around the culture pond to generate a horizontal circulation, and according to the hydraulic principle of the eddy current and the density difference layer, the relative density of the bottom water in the center of the culture pond is formed. Still, it helps organic residues to pool to the center of the pool.

According to the chemical and physical properties and hydraulic principles of impurities in the aquaculture sewage, the present invention utilizes the principle of natural photochemical catalytic oxidation of the thin water layer to denitrify and detoxify, supplement oxygen, inhibit algae and inhibit bacteria, and adopt hydraulic pollution accumulation and dynamic sewage introduction to form pond water Mix well and improve the environmental conditions of the bottom water, use the principle of shallow sedimentation to separate suspended organic matter in the water, use photochemical oxygen generation and atmospheric natural reoxygenation to increase oxygen in the water body, and the breeding sludge is naturally dehydrated and dried in the tank, and the breeding wastewater is recycled All the processing will be reused for breeding and no longer discharged. In addition, a small amount of organic dry sludge removed from the treatment facilities can be used as agricultural organic fertilizer resources on site. It realizes the "zero discharge" of circulating aquaculture and aquaculture sewage. It is a multi-functional, low-cost, and effective water purification method that meets environmental protection requirements. It is suitable for water quality management of sea and freshwater pond aquaculture.

Description of drawings

Fig. 1 is a schematic diagram of the system of the water purification method of the present invention.

Fig. 2 is a system schematic diagram of the water body purification method using the purified water redistribution ditch in the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings.

Referring to Fig. 1, the water body purification method of the present invention can pass through the sewage collection pipe device 2, the central sewage discharge pipe 3, the water pump 4, the water delivery pipe 5, the water distributing device 6, the shallow water pipe device 2 that are arranged at the central bottom of the aquaculture pond 1 of the gentle pot bottom type. The natural light circulation water purification system composed of layer sedimentation tank 7 and actinic slope 8 is realized. The sewage collection pipe device 2 is composed of 8 perforated sewage collection hard plastic pipes and 1 sewage discharge pipe, which is used to collect the residue at the bottom of the pool and the bottom layer of inferior quality. The central blowdown pipe 3 is a socket hard plastic pipe, which can make waste water and residues with higher organic loads be lifted into the shallow sedimentation tank 7 by the water pump 4 through the water delivery pipe 5 . The water shallow sedimentation tank 7 and the thin water layer actinic slope 8 are integrated with the dam body of the culture pond 1, the shallow sedimentation tank 7 is located on the side dam of the culture pond 1, and the actinization slope 8 is formed by the side slope of the culture pond 1 constitute. The depth of the shallow sedimentation tank 7 is about 0.5 meters, the slope of the actinic slope 8 is about 45 degrees, and the width (that is, the flow of the liquid on it) is 1.5 m. The water distribution device 6 can be a porous tube water distribution device, so that the culture wastewater is distributed longitudinally in the shallow sedimentation tank 7 .

During operation, the water pump 4 lifts the high-concentration aquaculture wastewater in the central bottom of the aquaculture pond 1 to the shallow sedimentation tank 7, and distributes the aquaculture wastewater in the shallow sedimentation tank 7 in the longitudinal direction through the porous pipe water distribution device 6, where solid-liquid separation is performed. Remove suspended organic matter. The depth of the shallow water is 0.4-0.5 meters, the residence time is 30 minutes, the water outlet velocity is 1.0m ³ /mh, and the solid-liquid separation is carried out under the condition of near "zero" velocity. In addition, while the suspended organic matter is removed in the shallow sedimentation tank 7, part of the natural photochemical catalytic oxidation can also be performed. The aquaculture wastewater that removes suspended organic matter overflows with a thin water layer and flows through the inclined plane 8 along the width direction with a thickness of no more than 0.3 mm, where the thin water layer is naturally photochemically catalyzed to oxidize, denitrify, detoxify, supplement oxygen, inhibit algae, and inhibit bacteria to regenerate the water. Then get back to the breeding pond 1 for recycling. In addition, the horizontal circulation is caused by the aerator (not shown) arranged around the culture pond 1. According to the hydraulic principle of the eddy current and the density difference layer, the relative stillness of the bottom water in the center of the culture pond 1 is formed, which contributes to The organic residues are collected to the center of the pool; and then the waste water and residues with higher organic loads are lifted by the water pump 4 to the shallow sedimentation tank 7 through the sewage collecting pipe device 2, thereby forming the circulation of the water body.

Referring to FIG. 2 , in order to redistribute the purified aquaculture wastewater or flushing pond wastewater to other aquaculture ponds, a purified water redistribution ditch 9 can be set between the shallow sedimentation tank 7 and the smooth slope 8 . The aquaculture wastewater overflowing from the shallow sedimentation tank 7 to remove organic suspended matter first enters the purified water redistribution ditch 9 , and then overflows onto the smooth slope 8 by the purified water redistribution ditch 9 . Wherein part or all of the water processed by the shallow sedimentation tank 7 can be transported to other culture ponds by a 0.15 meter wide purified water redistribution ditch 9 through a lock tube 10 for use. In addition, a layered drain outlet (not shown in the figure) may also be provided between the shallow sedimentation tank 7 and the purified water redistribution ditch 9 .

In the early stage of pond culture, the water purification system does not need to be operated. At this time, the shallow sedimentation tank 7 is used as a sludge natural drying tank. The organic sludge deposited in the tank during the circulation and purification of the above-mentioned aquaculture wastewater becomes solid after natural dehydration, and is manually shoveled out for resource utilization of forest organic fertilizer.

The above-mentioned device can not only meet the requirements of aquaculture for water environment quality, but also prevent the occurrence of environmental pollution problems caused by the discharge of aquaculture wastewater.

The present invention regenerates the water by adopting shallow sedimentation to separate the suspended organic matter in the water and the natural photochemical catalysis of the thin water layer, denitrification and detoxification, supplementing oxygen, inhibiting algae and inhibiting bacteria, and the purified oxygen-enriched water flows back to the culture pond for recycling, resulting in a pond vertical flow of water. This water circulation mode forms the overall flow of water in the aquaculture pond, which is conducive to breaking the stratification of the water body and improving the environmental quality of the pond bottom.

Referring to Tables 1 to 3, by chemical oxygen demand (COD) before and after treatment, suspended solids (SS), "three N" and phosphate measurements, it can be seen that the water purification method of the present invention can reduce the solubility of aquaculture water Ammonia nitrogen, nitrite nitrogen, nitrate nitrogen, and suspended solids and organic matter. Water inflow wherein refers to the water body of the inlet position of shallow sedimentation tank 7, and water outfall refers to the water body that returns to culture pond 1 through inclined plane 8.

Table 1 to the removal effect of COD in wastewater COD measurement times Influent mg/l Effluent mg/l Removal rate% 1 383.6 284.6 25.81 2 318.6 207.3 34.93 3 358.8 262.4 26.86 4 375.2 287.0 23.51 5 392.2 297.8 23.77 average removal rate 26.98

Table 2 to the removal effect of SS in wastewater SS measurement times Influent mg/l Effluent mg/l Removal rate% 1 182.5 30.5 83.29 2 186.5 27.5 85.25 3 180.2 33.0 81.69 4 187.8 40.0 78.70 5 194.0 41.5 78.61 average removal rate 81.51

Table 3 Removal effect of "three N" and phosphate in wastewater project Influent mg/l Effluent mg/l Removal rate% Nitrate nitrogen 0.4190-0.5575 0.3705-0.4325 10.37-27.35 Nitrite nitrogen 0.0550-0.1526 0.0218-0.0488 22.45-44.74 Ammonia nitrogen 0.1632-0.4355 0.0337-0.2775 13.39-79.53 Phosphate 0.1580-0.1920 0.0960-0.1070 39.24-44.27

In addition, the nitrite nitrogen in the bottom water of the pond was also measured, and the concentration of nitrite nitrogen in the bottom water of the culture pond by the water purification method of the present invention was 0.1628-0.1666 mg/liter, while the nitrite concentration in the bottom water of the culture pond was 0.1628-0.1666 mg/liter. The nitrogen concentration is 0.4307-0.4492 mg/L. It can be seen that the water body purification method of the present invention has greatly improved the water quality of the culture pond.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: the present invention can still be Modifications to the specific implementation of the invention or equivalent replacement of some technical features; without departing from the spirit of the technical solution of the present invention, should be included in the scope of the technical solution claimed in the present invention.

Claims (10)

1, a kind of water body purification method of cultivating pool comprises:

Step 1 is rested the breeding wastewater of growing pond central authorities bottom with water pump and is promoted in the tank;

Step 2 is isolated the suspended organic matter in the breeding wastewater in described tank;

Step 3 will be isolated the breeding wastewater of suspended organic matter after the natural light chemical catalytic oxidation is handled, and turn back to described cultivating pool again, form water cycle.

2, water body purification method according to claim 1, in the wherein said step 2, suspended organic matter is to adopt the shallow layer precipitating method in the described separation breeding wastewater.

3, water body purification method according to claim 2, in the wherein said shallow layer precipitating method, the degree of depth of shallow seated groundwater is a 0.3-0.6 rice, and the residence time is 20-40 minute, and going out water speed is 0.7-1.5m ³/ m.h.

4, water body purification method according to claim 3, the degree of depth of wherein said shallow seated groundwater are 0.4-0.5 rice, and the residence time is 30 minutes, and going out water speed is 1.0m ³/ m.h.

5, water body purification method according to claim 1, wherein said natural light chemical catalytic oxidation comprise the breeding wastewater of the isolating suspended organic matter inclined-plane of flowing through.

6, water body purification method according to claim 5, wherein the gradient on the inclined-plane of Cai Yonging is the 30-60 degree.

7, water body purification method according to claim 6, wherein the gradient on the inclined-plane of Cai Yonging is 45 degree.

8, water body purification method according to claim 5, the wherein said flow process of breeding wastewater on described inclined-plane of isolating suspended organic matter is greater than 1 meter, and thickness is less than 0.3 millimeter.

9, water body purification method according to claim 5, wherein the dam body of inclined-plane of Cai Yonging and tank and cultivating pool is an one.

10, according to each described water body purification method of claim 1～9, wherein when carrying out described water cycle, make the horizontal circulation of water generates of described cultivating pool by the oxygenating machine that is provided with around the described cultivating pool, form the static relatively of described cultivating pool central authorities bottom water.

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