Company Name: Jinhu County Huaneng Electromechanical Co., Ltd.
Chairman: Jiang Naiwen
Address: No. 198, Shenhua Avenue, Industrial Park, Jinhu County
1. Effect of aerators on improving the ecological environment of ponds
In the pond, in addition to fish and shrimp oxygen consumption, oxygen consumption is also required for phytoplankton, benthic animals, phytoplankton (night), microorganisms, sediment and organic matter decomposition. More than 90% of the dissolved oxygen in pond water comes from photosynthesis of phytoplankton, and less than 10% comes from the diffusion and transfer of oxygen in the air to the water body. The upper layer of dissolved oxygen in the pond is high, especially on sunny days, and it can reach supersaturation, such as 15 mg / L, while the bottom layer is very low, often below 1 mg / L. At night, due to the cessation of photosynthesis, even phytoplankton also joined the ranks of oxygen consumption, the dissolved oxygen in the fish pond continued to drop, and it dropped to a lower point in the middle of the night to early morning. The anoxic floating head of fish and shrimp often appeared during this time. Ponds have certain self-purification ability for ammonia and feces discharged from fish and shrimp. They mainly rely on phytoplankton absorption and oxidative decomposition of microorganisms (requires a large amount of dissolved oxygen).
2.The effects of aerators on improving the ecological environment of ponds are:
Oxygenation of water bodies. When the fish pond is under hypoxia, it can solve the floating head of fish and shrimp and reduce the loss caused by growth and death. When the dissolved oxygen in the upper layer is high on sunny days, it will start up. Because of the lifting, exchange, and circulation of the aerator, it will continuously promote the increase of dissolved oxygen in the middle and lower layers of water, and make the dissolved oxygen in the entire pool uniform, and the water temperature will be uniform. It is conducive to the rapid growth of fish and shrimp, reduces the bait coefficient, facilitates the oxidative decomposition of organic matter, and helps reduce the occurrence of diseases. In addition, the cyclic flow of the water body also promotes the uniform distribution and growth of phytoplankton, which is conducive to improving the primary productivity of the pond and the ability of the phytoplankton to absorb ammonia nitrogen, nitrite, nitrate, etc.
It can be seen that the role of the aerator not only aerates the water body, but also effectively promotes the improvement of the primary productivity of the pond, and greatly improves the self-purification capacity of the pond, thereby improving the water quality and ecological environment of the pond. The living habits of some cultured objects such as eel and shrimp have a good effect on promoting the healthy and rapid growth of fish and shrimp.
Aeration capacity of aerator
The main performance indicators of the aerator are defined as aeration capacity and power efficiency. Aeration capacity refers to the amount of oxygen added by an aerator to the water body per hour, the unit is kg / hour. Power efficiency refers to the amount of oxygen that an aerator consumes 1 degree of electricity to water, in kilograms per kilowatt hour. For example, the test result of a 1.5-kilowatt waterwheel aerator for Taizhou Jinqing Water Pump Factory, with a power efficiency of 1.7 kg / kWh, indicates that the machine consumes 1 kWh of electricity and can add 1.71 kg of oxygen to the water body; the aeration capacity is 2.59 kg / KWh, which means that the machine can add 2.59 kg of oxygen to the water body per hour. For example, the oxygenated water body is 1000 cubic meters, which is equivalent to an increase of 2.59 mg / 1 in dissolved oxygen in the water body. It should be noted that in order to have a unified comparison benchmark, the test of the aerator is carried out according to the standard under prescribed conditions (such as clean water, 20 ° C, a certain pool, and water dissolved oxygen from near zero, etc.), and Environmental conditions in fish ponds vary.
3. The current situation of using aerators in shrimp ponds at home and abroad
Abroad, Southeast Asia, South America, and other countries, shrimp ponds mainly use waterwheel aerators, and a small amount of push flow aeration aerators. They believe that these two aerators can make shrimp ponds circulate, which is suitable for shrimp habits and ecological environment, and is conducive to the healthy growth of shrimp. Due to the high density of shrimp farming, high temperature, high oxygen consumption rate and easy deterioration of water quality, the proportion of waterwheels is large, with a smaller area of 0.75 kilowatts and a larger area of 1.5 kilowatts of aerators6 Taiwan ~ 8.
Shrimp ponds in the south of Zhejiang, China mainly use waterwheels. In recent years, some freshwater fishponds in Guangdong have changed from impeller type to waterwheel type. They believe that to solve the problem of floating fish heads, the waterwheel will increase oxygen more quickly, which is conducive to energy conservation. The proportion of water tanks in shrimp ponds in the southern region is generally lower than foreign levels, but there are also parts of some ponds (high-yield) that have reached or close to foreign levels, such as in Hainan. Other types of aerators used in shrimp ponds in other areas of China are relatively heterogeneous, such as waterwheel type, impeller type, push flow type and so on. Generally, the proportion of aerator is small, and it is mainly to solve the hypoxia floating head of shrimp pond. However, in recent years, in order to avoid the outbreak of shrimp disease epidemic, many places have set up new demonstration experimental sites and districts, changed a lot of water-exchanging aquaculture models, and adopted many measures to improve the self-purification capacity of shrimp ponds and improve the ecological environment. Among them, increasing the proportion of the aerator is one of the main measures. The proportion of aerators in high-yield ponds (about 250 kg / mu) has reached 1 kilowatt per mu, and good economic benefits have been achieved.
4. Suggestions on the configuration of waterwheel aerators in shrimp farms under construction
The choice of aerator configuration mainly considers water conditions, breeding density, total intake and drainage energy consumption, etc.
Water source status: Whether the water source is abundant and whether the water quality has always been good. If it has always been good, you can consider less allocation: otherwise, more allocations, only change the water when the water quality is good.
Breeding density (mu production): the higher the more, the lower the less.
General water intake and drainage energy consumption: Generally, a field is built near the river. In the flood season, the inflow water may be self-flowing and siphoning. In the dry season, the water intake is pumped, and the drainage may be completely pumped. If the lifting time of the inlet pump is short, the head is small, and the drainage head is low, the energy consumption is small, and the amount of aerator can be considered less. On the contrary, the energy consumption is large, and the amount should be large.
Economic analysis: Consider the relative ratio of electricity price and shrimp price. If the local electricity price is relatively high and the shrimp price is relatively low, consider less allocation, and vice versa.
Aerators are currently commonly used in aquaculture. Due to cognitive biases, there are three misunderstandings in use. When using water for medicine, it emphasizes that the weather should be fine and good. Some farming householders say, "I have an aerator in the mouth of the pond." It seems that any aerator can be used.不 Normally do not open, the floating head is open, neglecting the increase function of the aerator. (3) It does not open during the day in fine weather, but it opens in the evening or at night. I mistakenly think that this can prevent floating heads. In order to get out of the misunderstanding, only by understanding the origin of the dissolved oxygen in the water body, the distribution characteristics of the dissolved oxygen, the influence of the amount of oxygen on the aquatic animals and the function of the aerator, can we better use the aerator and serve the fishery production. Contribute to the construction of new countryside. The aerator manufacturers introduce the relevant knowledge below to clear up doubts.