The Development of a High-Concentration Oxygenated Water Generator Based on Nanobubbles and Its Application

Water with a high concentration of oxygen is needed for the aquaculture industry in Japan. In the current study, the pressurized dissolution method was employed to generate high-concentration oxygenated water (HCOW) by producing oxygen nanobubbles in the water. In order to investigate factors such as temperature, geometric conditions, and their influence on the oxygen concentration, a special nanobubble generator was improved by changing the number and the diameter of the holes of the perforated plate in this study. Then, an experimental system where oxygen and water were separately introduced inside the proposed nanobubble generator was designed. The dissolved oxygen concentration was measured under different conditions. Finally, the produced HCOW was used to cultivate a mini-sunflower. Through a series of experiments, it was found that with the improved perforated plate, the dissolved oxygen concentration was increased and the nanobubble generator reached the saturation state quickly, while the mini-sunflower cultivated with the HCOW appeared to grow larger than that with tap water.