(746d) Development of Ozone Hydrate Generation System

Ozone (O₃) has a wide range of applications such as sterilization, deodorization and decolorization, but it is difficult to store and use O₃ molecules because they decompose oxygen (O₂) molecules by contact with each other. On the other hand, O₃ hydrate can take in each O₃ molecules separately in the cage structure of water molecules, and transport and store O₃ at a high concentration for a long time.

　Keio University succeeded in generating the world's first O₃ hydrate on a batch type laboratory scale, but a mass production method on a scale for practical use had not been established.
　Therefore, IHIGr developed a test system that continuously generates O₃ hydrate by circulating cooling water, and contacted O₃ gas and cooling water at a gas-liquid mixing part under high pressure.

　In this study, we designed the system for continuously generating O₃ hydrate, and aimed at establishing a method to generate O₃ hydrate continuously and at high concentration of O₃ hydrate.

Four parameters with high possibility of stably operating the system and contributing to the generation of high concentration of O₃ hydrate were selected and tested using the system.

The degree of influence of the four parameters was evaluated against the circulating water flow rate half-life time, the O₃ gas mass occupied in the O₃ + O₂ + CO₂ gas mass in the hydrate, which are an evaluation index of stably operating the system and high concentration O₃ hydrate production.

Based on the above optimum conditions, we investigate further O₃ concentration by changing the test conditions such as pressure conditions. As a result, the operation time tripled and the O₃ concentration in the hydrate was 15 times compared to before optimization.

From the above, we succeeded in continuously generating the world's first O₃ hydrate and established a method to generate high concentration O₃ hydrate.