Design and Test of Compound Mechanical Automatic Aeration in Aquaculture

Abstract:

Largescale and highdensity is the development trend of aquaculture in China. The impeller aerator is the most important aerators for aquaculture in China, with a market share of over 80%. The biofan is an aeration machine introduced from Japan in recent years. It can circulate the water up and down with low power during the day, and the photosynthesis of algae in the water can greatly increase the dissolved oxygen concentration of the water. However, it was difficult for biofan to play the role of aeration in rainy days or at night, so it must be used together with other aeration machines. Variable factor and fixed factor fuzzy frequency conversion aeration control of impeller aerators was first studied. Through the experiment, it was found that the variable factor fuzzy frequency conversion control improved the dissolved oxygen concentration of the water body faster and the control was more stable in the rated area. Subsequently, the simultaneous operation of the biofan and impeller aerator was analyzed. In this working mode, the distribution of dissolved oxygen in the water of the breeding pond was not only uniform on the upper and lower layers, but also the whole water body absorbed more oxygen produced by algae photosynthesis. The biofan dispersed the water body with high dissolved oxygen content near the impeller aerator to improve the working efficiency of the impeller aerator. The combined use of biofan and impeller aerator can save 7.80kW·h of electricity per day on sunny days and save 587.34kW·h in the third quarter. 