Circulating oxygenation method for aquaculture water at normal temperature and normal pressure

Abstract

The invention relates to the technical field of fishery breeding, in particular to a circulating oxygenation method for breeding water at normal temperature and pressure, which comprises the following steps: preparing a water storage tank with the diameter of not more than 20 meters and the depth of 3-5 meters; a water inlet is formed in the bottom of the water storage pond, a water outlet is formed in the lower portion of the side wall of the water storage pond, and it is ensured that the water outlet and the breeding fishpond form a water circulation channel. The sealed gas collection bag is arranged in the water storage tank to collect undissolved oxygen, the fan is combined to pressurize the collected oxygen again, and aeration is repeated through the aeration disc, so that the problem of waste caused by direct dissipation of the undissolved oxygen in the prior art is thoroughly solved, and the oxygen utilization rate is greatly increased; the whole process does not need additional pressurization equipment, efficient oxygenation can be achieved only through conventional pressurization of the fan, high investment and high energy consumption caused by the pressurization equipment are avoided, meanwhile, the operation process is simplified, and the use difficulty is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of fishery breeding technology, in particular to a water circulation and oxygenation method for breeding under normal temperature and pressure. BACKGROUND

[0002] In the modern aquaculture industry, the recirculating aquaculture technology has become an important direction for promoting the upgrading of the aquaculture industry because it can achieve more than 90% water resource recycling rate, and has the advantages of high efficiency, water saving, environmental friendliness, and strong controllability in the breeding process. In the recirculating aquaculture system, the water oxygen level directly determines the survival state, growth rate and health of the breeding organisms, so the oxygenation technology is the key link to ensure the stable development of high-density breeding. At present, the industry mainly relies on mechanical oxygenation, physical and chemical oxygenation and biological oxygenation to realize water oxygenation.

[0003] In the existing oxygenation technology, the pure oxygen oxygenation related technology is widely used for the breeding scene with high oxygen demand. However, the existing technology has the following problems: under normal temperature and pressure, only part of the pure oxygen can be dissolved after being introduced into the water, and the undissolved oxygen will directly overflow into the air, causing a lot of waste. In order to reduce waste, some technologies try to improve the aeration equipment or increase the pressure to improve the dissolution efficiency. The increase of pressure requires additional pressure equipment, which not only increases the initial equipment investment cost, but also increases the energy consumption during breeding. Although improving the aeration equipment can improve the single dissolution rate, it cannot solve the problem of recycling of undissolved oxygen, and a large amount of oxygen is still lost. When the breeding scale is expanded and the demand for high oxygen water is increased, the existing technology either cannot continuously supply sufficient high oxygen water due to serious oxygen waste, or cannot balance efficiency and cost due to complex equipment operation and high energy consumption. Therefore, it is difficult to realize efficient recycling and recycling of undissolved oxygen under normal temperature and pressure through a simple and easy-to-operate process, which affects the stable operation of the breeding system and the final output benefit. SUMMARY

[0004] In view of the shortcomings of the prior art, the present application provides a water circulation and oxygenation method for breeding under normal temperature and pressure, which solves the problems of easy dispersion and waste of undissolved oxygen in the existing pure oxygen oxygenation technology under normal temperature and pressure, and the need for additional pressure equipment to increase the cost and energy consumption.

[0005] To achieve the above purpose, the present application realizes the following technical scheme: a water circulation and oxygenation method for breeding under normal temperature and pressure, comprising:

[0006] A water storage tank is configured, the diameter of the water storage tank is not more than 20 meters, and the depth of the water storage tank is 3-5 meters;

[0007] A water inlet is arranged at the bottom of the water storage tank, and a water outlet is arranged at the lower part of the side wall of the water storage tank to ensure that the water outlet and the breeding fish tank form a water flow channel;

[0008] The volume of the water storage tank is adjusted according to the water exchange amount required by the fish culture pond, so that the residence time of the water in the water storage tank is 20 minutes;

[0009] The aerator is fixed on the bottom of the water storage tank, and the aerator uniformly covers the bottom area of the water storage tank;

[0010] The gas collection bag is completely covered on the water surface of the water storage tank, the edge of the gas collection bag extends into the water 50 cm away from the bottom of the tank, and is tightly attached to the inner wall of the water tank, so that a sealed space is formed at the upper part of the water surface for preventing undissolved oxygen from escaping and collecting oxygen;

[0011] The fan, pure oxygen storage device, gas collection bag and aerator are respectively arranged in place through the conveying pipeline;

[0012] Through the water inlet at the bottom of the water storage tank, the water to be oxygenated for aquaculture is injected into the water storage tank until the water reaches the preset water level, which is 0.5-1 meters away from the top of the water storage tank, and ensures that the water depth is more than 3 meters;

[0013] Start the fan, inhale pure oxygen from the pure oxygen storage device, and deliver the pure oxygen to the aerator at the bottom of the water storage tank after being pressurized by the fan;

[0014] The pure oxygen is dispersed into small bubbles by the aerator, and the small bubbles fully contact and dissolve with the water in the water storage tank to increase the dissolved oxygen concentration of the water;

[0015] Collect undissolved pure oxygen bubbles, which naturally rise to the water surface and are completely collected by the gas collection bag;

[0016] Extract the collected undissolved pure oxygen from the gas collection bag by the fan, and deliver the undissolved pure oxygen to the aerator after being pressurized again, and repeat the "aeration-dissolved oxygen" operation;

[0017] While repeating the "aeration-recovery-re-aeration" process, when the water saturation of the water in the water storage tank reaches more than 300%, deliver the high-dissolved-oxygen water to the fish culture pond through the water outlet, and simultaneously supplement the water to be oxygenated for aquaculture through the water inlet, to keep the total amount of water in the water storage tank stable.

[0018] Further, the water storage tank has a diameter of not more than 20 meters and a depth of 3-5 meters, including:

[0019] Select or build a water storage tank with a diameter of not more than 20 meters and a depth of 3-5 meters.

[0020] Further, the fan, pure oxygen storage device, gas collection bag and aerator are respectively arranged in place through the conveying pipeline, including:

[0021] The fan is placed on the ground outside the water storage pool or fixed on a support floating on the water surface below the gas collection bag;

[0022] The fan, the pure oxygen storage device, the gas collection bag and the aerator are connected by a conveying pipeline to ensure effective transmission and circulation of oxygen.

[0023] Further, the water to be oxygenated is injected into the water storage pool through the water inlet at the bottom of the water storage pool until the water reaches the preset water level, comprising:

[0024] The water flow rate at the water inlet at the bottom of the water storage pool is controlled to be not more than 2m 3 / s;

[0025] The water flow rate at the water outlet at the lower part of the side wall of the water storage pool is controlled to be not more than 2m 3 / s.

[0026] Further, the pure oxygen is dispersed into micro-bubbles by the aerator, which fully contacts and dissolves with the water in the water storage pool to improve the dissolved oxygen concentration of the water, comprising:

[0027] The fan is started, and the pure oxygen in the pure oxygen storage device is pumped to the fan for pressurization;

[0028] The pressurized pure oxygen is conveyed to the aerator at the bottom of the water storage pool through the conveying pipeline;

[0029] The aerator disperses the pure oxygen into micro-bubbles.

[0030] Further, the undissolved pure oxygen bubbles are collected, and the undissolved pure oxygen bubbles naturally rise to the water surface and are completely collected by the gas collection bag, comprising:

[0031] The undissolved pure oxygen bubbles contact the water body again during the rising process in the water body;

[0032] After the undissolved pure oxygen bubbles reach the water surface, they enter the sealed space formed by the gas collection bag.

[0033] Further, the collected undissolved pure oxygen is extracted from the gas collection bag by the fan, and the undissolved pure oxygen is pressurized again and conveyed to the aerator, and the "aeration-oxygen dissolution" operation is repeated, comprising:

[0034] The fan extracts the undissolved pure oxygen from the gas collection bag at a preset rate;

[0035] The fan pressurizes the extracted undissolved pure oxygen again, and the pressurization strength is not less than the pressurization strength of the first aeration;

[0036] The undissolved pure oxygen pressurized again is conveyed to the aerator to be dispersed into micro-bubbles again and contacted with the water body.

[0037] Further, while repeating the "aeration-recovery-re-aeration" process, when the dissolved oxygen saturation of the water in the storage pool reaches 300% or more, high-dissolved-oxygen water is delivered to the fish farming pool through the outlet, while simultaneously replenishing the water to be oxygenated through the inlet, keeping the total amount of water in the storage pool stable, including:

[0038] When the dissolved oxygen saturation of the water in the storage pool continues to reach 300% or more, high-dissolved-oxygen water is delivered to the fish farming pool through the outlet at a preset flow rate;

[0039] The water to be oxygenated is replenished through the inlet at a rate matching the delivery flow rate of the outlet;

[0040] Through flow control, the total amount of water in the storage pool is kept stable during the oxygenation process.

[0041] Further, the method further includes:

[0042] When the water temperature is below 10℃, adjust the parameters in the circulating oxygenation process according to the water temperature;

[0043] The parameter adjustment includes: reducing the pressure intensity of the fan, and controlling the bubble diameter formed by aeration to 5-8mm.

[0044] Further, the method further includes:

[0045] When the water temperature is between 20-30℃, adjust the parameters in the circulating oxygenation process according to the water temperature;

[0046] The parameter adjustment includes: increasing the pressure intensity of the fan, and controlling the bubble diameter formed by aeration to 0.3-0.8mm;

[0047] The parameter adjustment further includes: shortening the residence time of undissolved oxygen in the gas collection bag.

[0048] Compared with the prior art, the beneficial effects of the present application are:

[0049] The present application solves the problem of waste of undissolved oxygen by collecting undissolved oxygen in a sealed gas collection bag in the water storage tank, and combining a fan to re-pressurize the collected oxygen and repeat aeration through an aeration disc, greatly improving oxygen utilization; the entire process does not require additional pressurization equipment, and only relies on conventional pressurization of the fan to achieve efficient oxygenation, avoiding high investment and high energy consumption caused by pressurization equipment, while simplifying the operation process and reducing the use difficulty; by flexibly adjusting the size of the water storage tank, the pressurization strength of the fan and the bubble diameter and other parameters, different needs from small breeding enterprises to large-scale fish farms can be adapted; and the oxygenation parameters can be adjusted according to the change of water temperature, combined with the closed loop design of water body continuous updating and oxygen recycling, the water body dissolved oxygen saturation is kept stable, the breeding system is kept stable, and the breeding output benefit is improved. BRIEF DESCRIPTION OF DRAWINGS

[0050] Figure 1 It is a system structure schematic diagram of the present application;

[0051] Figure 2 It is an oxygen circulation flow chart of the present application;

[0052] Figure 3 It is an aeration-recovery process flow chart of the present application;

[0053] Figure 4 It is a temperature adjustment control chart of the present application;

[0054] Figure 5 It is a fluid balance schematic diagram of the present application. DETAILED DESCRIPTION

[0055] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0056] Please refer to Figures 1-5 The present application provides a water circulation oxygenation method for breeding at normal temperature and pressure, comprising:

[0057] A water storage tank is configured, the diameter of the water storage tank is not more than 20 meters, and the depth of the water storage tank is 3-5 meters;

[0058] A water inlet is arranged at the bottom of the water storage tank, and a water outlet is arranged at the lower part of the side wall of the water storage tank to ensure that the water outlet forms a water flow channel with the breeding fish tank;

[0059] The volume of the water storage tank is adjusted according to the required water exchange of the breeding fish tank, so that the residence time of the water in the water storage tank is 20 minutes;

[0060] Fix the aerator on the bottom of the water storage pool, and ensure that the aerator evenly covers the pool bottom area of the water storage pool;

[0061] Cover the gas collection bag completely on the water surface of the water storage pool, and extend the edge of the gas collection bag into the water 50 cm away from the pool bottom, so as to form a sealed space in the upper part of the water surface for preventing the escape of undissolved oxygen;

[0062] Arrange the fan, pure oxygen storage device, gas collection bag and aerator in place through the conveying pipeline;

[0063] Through the water inlet at the bottom of the water storage pool, inject the water to be oxygenated into the water storage pool, until the water body reaches the preset water level, which is 0.5 meters to 1 meter away from the top of the water storage pool, and ensures that the water depth is more than 3 meters;

[0064] Start the fan, inhale pure oxygen from the pure oxygen storage device, and deliver the pure oxygen to the aerator at the bottom of the water storage pool after being pressurized by the fan;

[0065] The pure oxygen is dispersed into small bubbles by the aerator, and the small bubbles fully contact and dissolve with the water body in the water storage pool to improve the dissolved oxygen concentration of the water body;

[0066] Collect undissolved pure oxygen bubbles, which naturally rise to the water surface and are completely collected by the gas collection bag;

[0067] Extract the collected undissolved pure oxygen from the gas collection bag by the fan, and deliver the undissolved pure oxygen to the aerator after being pressurized again, and repeat the "aeration-dissolved oxygen" operation;

[0068] While repeating the "aeration-recovery-re-aeration" process, when the water body in the water storage pool reaches a dissolved oxygen saturation of more than 300%, deliver the high-dissolved-oxygen water to the fish breeding pond through the water outlet, and simultaneously supplement the water to be oxygenated through the water inlet, to keep the total amount of water in the water storage pool stable.

[0069] Specifically, select a suitable site to build a water storage pool, determine the diameter of the water storage pool to be no more than 20 meters according to the breeding scale, and control the depth to be 3 to 5 meters. This size provides sufficient space for water and oxygen to fully contact, and is also convenient for subsequent component arrangement and operation. An inlet is provided at the bottom of the water storage pool, and an outlet is provided at the lower part of the side wall, so that the outlet directly communicates with the fish breeding pond to form a smooth water flow channel, ensuring that the oxygenated water is delivered to the fish pond in time, and the water to be oxygenated enters the water storage pool smoothly.

[0070] According to the daily water exchange amount of the fish pond, the formula V=Q*t (wherein V is the volume of the water storage pool, unit: cubic meter; Q is the daily water exchange amount of the fish pond, unit: cubic meter / day; t is the residence time of the water in the water storage pool, which is fixed at 20 minutes, and t=20 / (24*60)=1 / 72 days when converted into days) is used to accurately adjust the volume of the water storage pool to ensure that the residence time of the water in the water storage pool is exactly 20 minutes, so that the oxygen has enough time to dissolve, and the water renewal efficiency of the fish pond is not affected.

[0071] The aeration disc is uniformly fixed on the bottom of the water storage pool to ensure that it completely covers the pool bottom area, so that the subsequent aeration bubbles are uniformly distributed, and the dissolved oxygen is uniform. The gas collection bag is completely covered on the water surface of the water storage pool, and the edge is tightly attached to the pool wall to form a sealed space, which prevents the undissolved oxygen from escaping, and solves the problem of oxygen loss and waste in the prior art. Then the fan, the pure oxygen storage device, the gas collection bag and the aeration disc are arranged in place through the conveying pipeline to ensure stable connection and prepare for oxygen transmission and circulation.

[0072] The water to be oxygenated for aquaculture is injected through the water inlet to a preset water level (0.5-1 m from the top of the pool) to avoid water overflow affecting the gas collection effect. After starting the fan, the fan inhales pure oxygen from the pure oxygen storage device and pressurizes it to be delivered to the aeration disc to form tiny bubbles, which are fully contacted and dissolved with the water body during rising. Undissolved bubbles are collected by the gas collection bag, and the fan is extracted again for pressurized aeration, and the "aeration-dissolved oxygen" operation is repeated. The oxygen utilization rate in this process can be calculated by the formula , wherein η is the oxygen recycling rate; O1 is the amount of dissolved oxygen in the first aeration, unit: kg; O2 is the amount of dissolved oxygen in the first cycle aeration, unit: kg; O n is the amount of dissolved oxygen in the nth cycle aeration, unit: kg; and O 总 is the total amount of oxygen output from the pure oxygen storage device, unit: kg. Through this circulation process, the oxygen utilization rate is greatly improved, and the waste is reduced.

[0073] When the water oxygen saturation reaches more than 300%, the high-dissolved-oxygen water is delivered to the fish pond through the water outlet, and the water inlet simultaneously supplements the water to be oxygenated, to keep the water quantity of the water storage pool stable. The whole process does not need additional pressurizing equipment, reduces equipment investment and energy consumption, and is simple to operate, suitable for various aquaculture scales, and solves the problems of oxygen waste, complex equipment, high energy consumption, and difficulty in balancing efficiency and cost in the prior art.

[0074] In the embodiment, the water storage pool is configured, the diameter of the water storage pool is not more than 20 meters, and the depth of the water storage pool is 3-5 meters, including:

[0075] The water storage pool is selected or built, the diameter of the water storage pool is not more than 20 meters, and the depth of the water storage pool is 3-5 meters.

[0076] Specifically, when configuring the water storage pool, a water storage pool with a suitable size is selected or built according to the breeding scale, and the size is calculated based on a conventional volume formula V=Sxh (wherein V is the volume of the water storage pool, in cubic meters; S is the bottom area of the water storage pool, in square meters, S=pi r 2 , r is the radius of the water storage pool, in meters; and h is the depth of the water storage pool, in meters), which is a conventional volume calculation method in the prior art and will not be described in detail.

[0077] For a small breeding scene, a water storage pool with a diameter of 8 meters and a depth of 3 meters is selected or built, which can meet the requirement of water body residence for 20 minutes and does not waste space and resources; for a medium breeding scene, the diameter of the water storage pool is set to 12 to 18 meters, and the depth is about 4 meters, which is suitable for medium water exchange; for a large-scale fish farm, a water storage pool with a diameter of not more than 20 meters and a depth of 5 meters is selected or built, which can meet the continuous demand for high-dissolved oxygen water for large-scale breeding. Different sizes of water storage pools are matched with reasonable volume adjustment to accurately adapt to different breeding scenes, ensure the efficiency of oxygen dissolution, avoid resource waste, and improve the scene adaptability of the method.

[0078] In the embodiment, the fan, the pure oxygen storage device, the gas collecting bag and the aerator disc are respectively arranged in place through the conveying pipeline, which comprises the following steps:

[0079] The fan is placed on the ground outside the water storage pool, or the fan is fixed on a support floating on the water surface, and the support is located below the water surface of the gas collecting bag;

[0080] The fan, the pure oxygen storage device, the gas collecting bag and the aerator disc are connected through the conveying pipeline to ensure the effective transmission and circulation of oxygen.

[0081] Specifically, when the fan, the pure oxygen storage device, the gas collecting bag and the aerator disc are arranged, the placement position of the fan is selected according to the surrounding site conditions of the water storage pool and the breeding operation demand. If the surrounding ground space is sufficient and convenient for maintenance, the fan is placed on the ground outside the water storage pool to reduce the influence of water fluctuation on the fan and prolong the service life of the equipment; if the ground space is limited or the pipeline arrangement needs to be simplified, the fan is fixed on a floating support below the water surface of the gas collecting bag to shorten the oxygen transmission path and reduce the transmission loss.

[0082] Regardless of the selected placement method, the components are tightly connected through the conveying pipeline to ensure that the pipeline interface is well sealed. During this process, the transmission flow rate of oxygen in the pipeline needs to meet Q 氧 =vxS 管 (wherein Q 氧 is the transmission flow rate of oxygen, in cubic meters per second; v is the flow rate of oxygen in the pipeline, in meters per second; S 管A is the cross-sectional area of the pipeline, in square meters, and Q is the flow rate of the fluid, in cubic meters per second. This formula is a common flow rate calculation formula in fluid mechanics and is prior art. By reasonable layout and flow control, different site environments can be adapted to, oxygen can be effectively transmitted and circulated, oxygen utilization can be improved, layout processes can be simplified, and operation difficulty can be reduced.

[0083] In the embodiment, the water to be oxygenated is injected into the water storage tank through the water inlet at the bottom of the water storage tank until the water reaches the preset water level, including:

[0084] The water flow rate at the water inlet arranged at the bottom of the water storage tank is controlled to be not more than 2 m 3 / s;

[0085] The water flow rate at the water outlet arranged at the lower part of the side wall of the water storage tank is controlled to be not more than 2 m 3 / s.

[0086] Specifically, when the water to be oxygenated is injected through the water inlet at the bottom of the water storage tank, the water flow rate at the water inlet is strictly controlled to be not more than 2 cubic meters per second, and the water flow rate at the water outlet is also controlled to be not more than 2 cubic meters per second, to ensure that the water inlet and outlet flow rates meet Q 进 = Q 出 (in which Q 进 is the water inlet flow rate, in cubic meters per second; and Q 出 is the water outlet flow rate, in cubic meters per second).

[0087] The gentle water flow rate makes the water enter and exit the water storage tank smoothly, avoids the water flow being too fast to cause the water to roll violently and damage the stability of the aeration bubbles, and ensures that the bubbles are uniformly distributed and fully contacted with the water to dissolve. At the same time, the stable water inlet and outlet flow rates are matched to ensure that the total amount of water in the water storage tank is always stable, to provide a stable water environment for continuous circulation oxygenation and ensure the consistency of the oxygenation effect, avoiding the influence of water flow problems on the living environment of the cultured organisms.

[0088] In the embodiment, the pure oxygen is dispersed into micro-bubbles by the aeration disc, and the micro-bubbles are fully contacted with the water in the water storage tank and dissolved to improve the dissolved oxygen concentration of the water, including:

[0089] Starting the fan, the pure oxygen in the pure oxygen storage device is pumped to the fan for pressurization;

[0090] The pressurized pure oxygen is delivered to the aeration disc at the bottom of the water storage tank through the delivery pipeline;

[0091] The aeration disc disperses the pure oxygen into micro-bubbles.

[0092] Specifically, after starting the blower, the blower extracts pure oxygen from the pure oxygen storage device and pressurizes it, and the pressurized pure oxygen is delivered to the aeration disc through the delivery pipeline. The aeration disc disperses the pure oxygen into tiny bubbles with a diameter of less than 2 mm. The oxygen dissolution efficiency of the bubbles in the water body is related to the bubble diameter, which can be calculated by formula 2 , where ε is the bubble oxygen dissolution efficiency; k is the proportionality coefficient (related to the water temperature and water quality, the value range under normal temperature and pressure is 0.8-1.2); d is the bubble diameter, unit: meter; t 接 is the contact time of the bubble with the water body, unit: second.

[0093] The bubble diameter of less than 2 mm can make the bubble rise in the water body at a moderate speed, have sufficient contact time, form a large contact interface with the water body, and allow the oxygen to be dissolved efficiently and quickly to improve the oxygen concentration in the water body. Compared with the problem of unstable bubble size and low dissolution efficiency in the prior art, the controllable bubble diameter design combined with the efficiency regulation of formula 2 can greatly improve the single aeration dissolution effect and reduce the invalid consumption of oxygen.

[0094] In the present embodiment, the undissolved pure oxygen bubbles are collected and naturally rise to the water surface and are completely collected by the gas collection bag, including:

[0095] The undissolved pure oxygen bubbles are in secondary contact with the water body during the rising process in the water body;

[0096] After the undissolved pure oxygen bubbles reach the water surface, they enter the sealed space formed by the gas collection bag.

[0097] Specifically, when the undissolved pure oxygen bubbles naturally rise in the water body, they will be in secondary contact with the surrounding water body. The amount of dissolved oxygen during the secondary contact process can be calculated by formula 3 二 = O 未1 × α (formula 3), where O 二 is the amount of oxygen dissolved by secondary contact, unit: kg; O 未1 is the amount of undissolved oxygen after the first aeration, unit: kg; and α is the secondary contact dissolution rate (value range: 0.1-0.2, related to the degree of water body turbulence).

[0098] Through secondary contact, part of the undissolved oxygen is further dissolved into the water body, increasing the dissolution opportunity. When the bubbles rise to the water surface, they directly enter the sealed space formed by the gas collection bag. Since there is no gap between the gas collection bag and the pool wall, the bubbles cannot escape and are completely collected. This process, combined with the secondary dissolution amount calculation of formula 3, not only improves the single dissolution rate, but also completely solves the problem of undissolved oxygen loss, laying a foundation for subsequent recycling and further improving the overall oxygen utilization rate.

[0099] In the embodiment, the undissolved pure oxygen collected in the gas collecting chamber is extracted by the fan, and the undissolved pure oxygen is re-pressurized and then delivered to the aerator plate, and the operation of "aeration-dissolved oxygen" is repeated, including:

[0100] The fan extracts the undissolved pure oxygen from the gas collecting chamber at a preset rate;

[0101] The fan re-pressurizes the extracted undissolved pure oxygen, and the re-pressurization strength is not lower than the initial aeration strength;

[0102] The re-pressurized undissolved pure oxygen is delivered to the aerator plate to be dispersed into small bubbles again and contacted with the water body.

[0103] Specifically, the fan extracts the undissolved pure oxygen from the gas collecting chamber at a preset rate, and the extraction rate is set according to the oxygen generation rate in the gas collecting chamber to ensure that the undissolved oxygen is extracted in time to avoid high gas pressure in the gas collecting chamber affecting bubble collection. The extracted undissolved pure oxygen is delivered to the fan, and the fan re-pressurizes it, and the re-pressurization strength is not lower than the initial aeration strength, that is, it meets P 再 ≥P 初 (Wherein P 再 is the oxygen pressure after re-pressurization, unit: Pascal; P 初 is the oxygen pressure during initial aeration, unit: Pascal).

[0104] Sufficient pressure strength ensures that the oxygen delivered to the aerator plate can still be dispersed into small bubbles meeting the requirements and has good dissolution conditions. The re-pressurized oxygen is dispersed into bubbles by the aerator plate, re-enters the water body for dissolution, and realizes oxygen recycling. Combined with pressure condition control, every part of oxygen can be fully utilized, the waste rate is greatly reduced, and additional oxygen supply is not required, reducing the cost of oxygen for aquaculture.

[0105] In the embodiment, while the "aeration-recovery-re-aeration" process is repeated, when the dissolved oxygen saturation of the water body in the water storage tank reaches 300% or more, the high-dissolved-oxygen water is delivered to the fish culture tank through the water outlet, and the water to be oxygenated is simultaneously supplemented through the water inlet to keep the total amount of water in the water storage tank stable, including:

[0106] When the dissolved oxygen saturation of the water body in the water storage tank continuously reaches 300% or more, the high-dissolved-oxygen water is delivered to the fish culture tank through the water outlet at a preset flow rate;

[0107] The water to be oxygenated is simultaneously supplemented to the water storage tank through the water inlet at a rate matching the delivery flow rate of the water outlet;

[0108] Through flow control, the total amount of water in the water storage tank is kept stable during the oxygenation process.

[0109] Specifically, in the repeated "aeration-recovery-re-aeration" process, the dissolved oxygen saturation of the water body in the water storage tank is continuously monitored, and when the dissolved oxygen saturation continuously reaches more than 300%, the high-dissolved-oxygen water is transported to the fish tank through the water outlet at a preset flow rate, and the water body to be oxygenated is supplemented through the water inlet at a rate matching the flow rate of the water outlet, so as to meet Q 出 = Q 补 (Wherein Q 出 is the flow rate of the water outlet, in cubic meters per hour; Q 补 is the flow rate of the water inlet, in cubic meters per hour).

[0110] Through flow balance control, the total amount of water in the water storage tank is always stable during the oxygenation process, neither the water body is reduced due to insufficient water supplement affecting the aeration effect, nor the water body is overflowed due to excessive water supplement. This dynamic balance water updating method, combined with the flow matching relationship, enables the oxygenation process to run stably and continuously, provides the fish tank with a continuous supply of high-dissolved-oxygen water, ensures the stability of the breeding environment, and improves the survival rate and growth state of the breeding organisms.

[0111] In this embodiment, the method further comprises:

[0112] When the water temperature is below 10°C, the parameters in the circulating oxygenation process are adjusted according to the water temperature;

[0113] The parameter adjustment includes appropriately reducing the pressure intensity of the fan to control the diameter of the aeration bubbles to be less than 2mm.

[0114] Specifically, when the water temperature is monitored to be below 10°C, the parameters in the circulating oxygenation process are adjusted according to the water temperature, and the parameter adjustment follows the formula d=a-b×T (Formula 4), wherein d is the diameter of the aeration bubbles, in millimeters; a is the base coefficient (the value is 13); b is the temperature influence coefficient (the value is 0.8); and T is the water temperature, in °C.

[0115] According to formula 4, the pressure intensity of the fan is appropriately reduced to control the diameter of the aeration bubbles to be less than 2mm. The water body has a higher oxygen solubility at low temperature, and a slightly larger bubble diameter can ensure that the bubble has enough residence time to complete the dissolution in the water body, avoiding the influence of slow rising of the too small bubble on the water circulation. Through parameter adjustment and application of formula 4, the oxygenation process is adapted to the low temperature environment, ensuring stable oxygenation efficiency at low temperature and normal breeding in low temperature seasons such as winter.

[0116] In this embodiment, the method further comprises:

[0117] When the water temperature is between 10°C and 35°C, the parameters in the circulating oxygenation process are adjusted according to the water temperature;

[0118] The parameter adjustment includes: increasing the pressurization strength of the fan, and controlling the bubble diameter formed by aeration to be 0.3-0.8 mm.

[0119] The parameter adjustment also includes: shortening the residence time of undissolved oxygen in the gas collecting bag.

[0120] Specifically, when the water temperature is between 10-35 DEG C, the circulating oxygenation process parameters are adjusted according to the water temperature, and the bubble diameter adjustment follows the formula d = c-d x T (formula 5), wherein d is the aeration bubble diameter, unit: mm; c is the basic coefficient (value is 11); d is the temperature influence coefficient (value is 0.3); T is the water temperature, unit: DEG C.

[0121] According to formula 5, the pressurization strength of the fan is increased, and the bubble diameter is controlled to be 0.3-0.8 mm, the smaller bubble diameter increases the contact area with the water body, and makes up for the insufficient of the water body dissolved oxygen capacity at high temperature. At the same time, according to the actual gas collecting efficiency and oxygen circulation demand, the residence time of undissolved oxygen in the gas collecting bag is shortened, usually controlled in the range of 5-15 seconds, to avoid the oxygen loss caused by too long residence time, and to ensure that the oxygen quickly participates in the circulation. Through parameter adjustment and application of formula 5, the oxygenation process is adapted to the high temperature environment, and sufficient oxygen is provided for the aquaculture water body in the high temperature season, to avoid the influence of insufficient dissolved oxygen on the growth of aquaculture organisms, and to ensure the stability of the whole year aquaculture.

[0122] To further verify the oxygenation effect and oxygen utilization rate advantage of the method of the application, under normal temperature and pressure conditions, two groups of experiments of "water body is exchanged once every three hours" and "water body is exchanged three times every hour" are set, the performance indexes of the present application and the existing mainstream oxygenation technology (fan air oxygenation, impeller oxygenation machine oxygenation, nanometer gas tube pure oxygen oxygenation) are compared, and the experimental data is as follows:

[0123] Table 1: Fish carrying capacity (taking 0.5-1 kg carp as an example) and pure oxygen utilization rate comparison under normal temperature and pressure conditions (unit: kg / m 3 )

[0124]

[0125] Table 2: Oxygenation effect comparison under normal temperature and pressure conditions (unit: mg / L)

[0126] From table 1, table 2, under different water temperature, different water exchange frequency, the fish carrying capacity of the present technology is 1.5-3 times of the prior art, the pure oxygen utilization rate is stably maintained at 98%-99%(the utilization rate of the existing nano gas pipe pure oxygen aeration technology is only 50%-65%), and the oxygenation effect(mg) is significantly higher than that of the prior art(the highest of the prior art is 18.5mg, and the lowest of the present technology is 23.4mg). The above data fully verify that the present application can effectively solve the problem of waste of oxygen escape in the prior art through the design of "sealed gas collection bag recycling undissolved oxygen + fan circulating pressurization aeration", and can realize efficient oxygenation without additional pressurization equipment, and can adapt to different water temperature, different water exchange frequency of breeding scene, and provide strong support for stable operation of breeding system and output benefit improvement.

[0127] In summary, the present application collects undissolved oxygen by setting a sealed gas collection bag in the water storage tank, and combines a fan to pressurize the collected oxygen again and repeatedly aerate through the aeration disc, completely solving the problem of waste caused by direct escape of undissolved oxygen in the prior art, greatly improving the oxygen utilization rate; the whole process does not need additional pressurization equipment, and can realize efficient oxygenation only by relying on the conventional pressurization of the fan, avoiding high investment and high energy consumption caused by pressurization equipment, and simplifying the operation process and reducing the use difficulty; by flexibly adjusting the size of the water storage tank, the pressurization strength of the fan and the diameter of the air bubbles and other parameters, different needs from small-scale breeding enterprises to large-scale fish farms can be adapted; and the oxygenation parameters can be adjusted according to the change of water temperature, and the closed loop design combining water body continuous updating and oxygen recycling is maintained, the water body dissolved oxygen saturation is stably maintained, the stable operation of the breeding system is ensured, and the breeding output benefit is improved.

[0128] It should be noted that in this paper, relationship terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or equipment.

[0129] Although the embodiments of the present application have been shown and described, it can be understood by those of ordinary skill in the art that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and spirits of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for circulating and increasing oxygen in water for aquaculture at normal temperature and pressure, characterized by, The method comprises the following steps: configuring a water storage pool with a diameter of not more than 20 meters and a depth of 3-5 meters; setting a water inlet at the bottom of the water storage pool and a water outlet at the lower part of the sidewall of the water storage pool to ensure that the water outlet forms a water flow channel with the fish breeding pool; adjusting the volume of the water storage pool according to the required water exchange amount of the fish breeding pool to ensure that the water stays in the water storage pool for 20 minutes; fixing the aerator at the bottom of the water storage pool to ensure that the aerator uniformly covers the pool bottom area of the water storage pool; completely covering the gas collection bag on the water surface of the water storage pool, with the edge of the gas collection bag extending into the water at a distance of 50 cm from the pool bottom, so as to form a sealed space at the upper part of the water surface for preventing undissolved oxygen from escaping and collecting oxygen; arranging the fan, the pure oxygen storage device, the gas collection bag and the aerator in place through the conveying pipeline; injecting the water to be oxygenated into the water storage pool through the water inlet at the bottom of the water storage pool until the water reaches a preset water level, which is 0.5-1 meter away from the top of the water storage pool and ensures that the water depth is more than 3 meters; starting the fan to inhale the pure oxygen from the pure oxygen storage device, and then conveying the pure oxygen to the aerator at the bottom of the water storage pool after being pressurized by the fan; dispersing the pure oxygen into micro-bubbles by the aerator, and fully contacting and dissolving the micro-bubbles with the water in the water storage pool to improve the dissolved oxygen concentration of the water; collecting the undissolved pure oxygen bubbles, which naturally rise to the water surface and are completely collected by the gas collection bag; extracting the collected undissolved pure oxygen from the gas collection bag by the fan, pressurizing the undissolved pure oxygen again, and then conveying the undissolved pure oxygen to the aerator, so as to repeat the "aeration-dissolved oxygen" operation; while repeating the "aeration-recovery-re-aeration" process, when the water saturation of the water in the water storage pool reaches more than 300%, conveying the high-dissolved-oxygen water to the fish breeding pool through the water outlet, and simultaneously supplementing the water to be oxygenated through the water inlet to keep the total amount of water in the water storage pool stable.

2. The water circulation oxygenation method for aquaculture at normal temperature and pressure according to claim 1, characterized by, The method comprises the following steps: selecting or building a water storage pool with a diameter of not more than 20 meters and a depth of 3-5 meters.

3. The method of claim 1, wherein the method is characterized by, The method comprises the following steps: placing the fan on the ground outside the water storage pool or fixing the fan on a support floating on the water surface, with the support being located below the gas collection bag at the water surface; connecting the fan, the pure oxygen storage device, the gas collection bag and the aerator through the conveying pipeline to ensure the effective transmission and circulation of oxygen.

4. The method of claim 1, wherein the method is characterized by, The method comprises the following steps: The water inlet is arranged at the bottom of the water storage pool, and the water flow speed is controlled to be not more than 2 m / s 3 / s; The water outlet is arranged at the lower part of the side wall of the water storage pool, and the water flow speed is controlled to be not more than 2 m / s. 3 / s.

5. The method of claim 1, wherein the method is characterized by, The method comprises the following steps: starting the fan to extract the pure oxygen in the pure oxygen storage device to the fan for pressurization; conveying the pressurized pure oxygen to the aerator at the bottom of the water storage pool through the conveying pipeline; dispersing the pure oxygen into micro-bubbles by the aerator.

6. The method of claim 1, wherein the method is characterized by, The method comprises the following steps: The undissolved pure oxygen bubbles contact the water body again during their rising in the water body; The undissolved pure oxygen bubbles enter the sealed space formed by the gas collection bag after reaching the water surface.

7. The method of claim 1, wherein the method is characterized by, The collected undissolved pure oxygen is extracted from the gas collection bag by the fan, and the undissolved pure oxygen is pressurized again and then delivered to the aeration disc, and the "aeration-oxygen dissolution" operation is repeated, including: The fan extracts the undissolved pure oxygen from the gas collection bag at a preset rate; The fan pressurizes the extracted undissolved pure oxygen again, and the pressurization strength is not lower than the pressurization strength during the initial aeration; The undissolved pure oxygen pressurized again is delivered to the aeration disc, so that it is dispersed into small bubbles again and contacts the water body.

8. The method of claim 1, wherein the method is characterized by, While repeating the "aeration-recovery-re-aeration" process, when the water body in the water storage pool has a dissolved oxygen saturation of 300% or more, high-dissolved-oxygen water is delivered to the fish breeding pool through the water outlet, and at the same time, the water to be oxygenated is supplemented through the water inlet, keeping the total amount of water in the water storage pool stable, including: When the water body in the water storage pool has a dissolved oxygen saturation of 300% or more, high-dissolved-oxygen water is delivered to the fish breeding pool through the water outlet at a preset flow rate; The water to be oxygenated is supplemented through the water inlet at a rate matching the delivery flow rate of the water outlet; Through flow control, the total amount of water in the water storage pool is kept stable during the oxygenation process.

9. The method of claim 1, wherein the method is characterized by, The method further includes: When the water temperature is below 10°C, adjust the parameters in the circulating oxygenation process according to the water temperature; Parameter adjustment includes: reducing the pressurization strength of the fan, and controlling the bubble diameter formed by aeration to be less than 2mm.

10. The method of claim 1, wherein the method is characterized by, The method further includes: When the water temperature is between 10°C and 35°C, adjust the parameters in the circulating oxygenation process according to the water temperature; Parameter adjustment includes: increasing the pressurization strength of the fan, and controlling the bubble diameter formed by aeration to be within a certain appropriate range; Parameter adjustment also includes: shortening the residence time of undissolved oxygen in the gas collection bag.

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