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Aquatic oxygen black technology, how to achieve pure oxygen zero waste?

In aquaculture, sewage treatment and other water treatment industry. It is very important to increase the oxygen content in the water. High dissolved oxygen can make aquatic animals and microorganisms better survive and grow. It can significantly improve the benefit of aquaculture and increase the content of probiotics in water. Especially in high density aquaculture, high dissolved oxygen must be maintained all the time. Once the dissolved oxygen is insufficient, it will produce quite serious consequences.

How to effectively increase the dissolved oxygen in water body, reduce energy consumption and improve the dissolved oxygen efficiency per unit water body? Is the aquatic practitioners have been assiduously in pursuit of the ideal. At present, there are roughly the following common ways of increasing oxygen in the market:
1. Water wheel aerator
This is the most common. General soil pond breeding, most of this way. A water wheel lifts water near the surface into the air, where it meets the air. It increases the amount of dissolved oxygen in the water. However, this method is generally only fixed on the surface of the pond, the water on the surface of the pond oxygenation effect is better, while the pond bottom water because there is no effective convection. Dissolved oxygen is not increased. And the bottom of the pond tends to be where the highest concentration of fish waste is. In the absence of oxygen, organic matter in fish droppings breaks down into harmful substances such as toxic hydrogen sulfide. These substances are also soluble in water. When the concentration of hydrogen sulfide and other substances in water accumulates to a certain degree, it will produce deadly toxicity to fish and shrimp in the water.

2. Fan aeration stone (nano aeration pipe)
The pressure of small fan is small, and it is only suitable for shallow water. The general water depth is not more than 80cm; Roots fans are used on large farms. Roots fan pressure is large, the air output is not small. For ordinary outdoor fish ponds, the relative power consumption is large. And Roots fan is generally used with nano aerator matching. After aeration, the diameter of the gas in the water is about 2-3mm. Under the action of buoyancy, the bubbles will rise to the surface quickly.
We know that. According to the common sense of physics, the dissolution efficiency of gas in liquid is related to the following factors: saturation solubility of gas, bubble diameter, liquid pressure, contact time, etc. Under the condition of aquatic products, because the saturation solubility and liquid pressure of oxygen in water are basically fixed, the factors that affect the dissolution efficiency of oxygen in water are only the bubble diameter and contact time. And the larger the bubble is, the more buoyant it is in the water. So there is a relationship between the two.

When the total gas volume remains constant, the smaller the bubble diameter is, the larger the total contact area between gas and liquid will be, and the higher the dissolution efficiency will be. Because the oxygen content in the air is only 21%, coupled with the bubble and water contact time is short, through the nano aeration pipe on water oxygenation, the effect is relatively limited.
3. Jet aeration and oxygen cone
Jet aeration is a kind of gas-liquid mixing method. Through the Venturi tube, the liquid is mixed with oxygen to form a bubble. In fresh water conditions, the current use of effluent bubble bubble, generally 1.5-3mm in diameter. Under seawater conditions, the bubble diameter is generally more than 1mm. The jet device should be connected with the pressurized water pump. Therefore, it also consumes electricity. The aeration cone can be connected behind the jet device. The aeration cone is a fiberglass can with a small top and a large bottom. When the velocity of the water decreases, the buoyancy of the bubble gradually exceeds the impact force of the water flow and tends to be suspended in the cone. Which increases the amount of time it stays in the water. It increases the solubility of oxygen in water.

But if the bubbles continue to enter the oxygen cone, the bubbles in the oxygen cone will dissolve each other and form large bubbles. This in turn becomes a resistance factor to the flow of water. The ideal model of an oxygen cone would be broken. It's less efficient at dissolving oxygen. If the gas entering the oxygen cone is pure oxygen. It would be a huge waste of pure oxygen. Therefore, there are certain technical requirements for the use of oxygen cones.

4. The misunderstanding of pure oxygen increasing oxygen
Many people oxygenate aquaculture water through the above methods, but the effect is often not satisfactory. Especially when high density aquaculture or aquatic transportation, water hypoxia will bring great losses to farmers. So many people oxygenate the water with pure oxygen. But through our visits and our observations. It was found that most people used a combination of nano aerators and pure oxygen (oxygen cylinders). The bubble diameter is between 1-3mm, and most of the pure oxygen spills rapidly, resulting in great waste. At the same time, frequent changes of oxygen cylinders also lead to a significant increase in labor costs.

The pioneering characteristics of Lanling pure oxygen dissolving device:
In order to develop a new way of using pure oxygen to add oxygen to water body. Blue Ling water treatment equipment has carried on the bold idea and a lot of tests. Pioneering invention of waste-free pure oxygen dissolving oxygen device. It has a special reactor and oxygen cylinders connected, with minimal power consumption, water and oxygen fully mixed and dissolved. The water with high dissolved oxygen flows out from the bottom of the equipment. The water does not contain bubbles, so bubbles will not escape. The equipment controls the water level in the container through the automatic control system. So as to prevent pure oxygen leakage. Device effluent has a high dissolved oxygen value but no bubbles. Pure oxygen is not wasted.

In theory, it takes 3 kilograms of pure oxygen to add 1PPM of dissolved oxygen to 1,000 cubic meters of water. But in fact, the weight of pure oxygen consumed by conventional methods can reach 60 kilograms. That is to say, the utilization rate of pure oxygen is less than 5% when the water is oxygenated by ordinary nano aerator and jet device. The pure oxygen dissolving device can achieve 100% utilization of pure oxygen. It greatly reduces the cost of oxygen and the labor cost caused by replacing oxygen cylinders.
In the application of the earth pond, the inlet flow of the first pure oxygen dissolver is 13T/H, and it is driven by a 1.85kW water pump. The dissolved oxygen in the inlet is 6.7 PPM, and the dissolved oxygen in the outlet is 25.3 PPM. The dissolved oxygen efficiency is 100%, the dissolved oxygen speed is about 100G/H, and the dissolved oxygen rate is kg/hour. Take a 5 mu soil pond as an example, to the total water volume of 5000 cubic calculation, add 3ppm dissolved oxygen to the soil pond water, only 15KG of pure oxygen, electricity consumption of about 10 degrees.

The dissolved oxygen degree of water in the pool and the dissolved oxygen degree of water from pure oxygen aerator:

Both the dissolved oxygen efficiency and the overall energy consumption have a qualitative leap compared with the previous methods of increasing oxygen.

After the outlet water was placed for 24 hours, the dissolved oxygen remained at a high level:

The pure oxygen dissolver has a higher dissolved oxygen content in the effluent, which can be mixed with the effluent in the filtration system for dilution. In recirculating aquaculture. It is recommended that the pure oxygen dissolver be installed at the front end of the biofilter. After the high dissolved oxygen flow to the biofilter, it will be helpful for the rapid propagation of aquatic probiotics.

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