Apparatus for mixing materials dissolved in a high-pressure working fluid

A mixing apparatus comprising:

• a production unit configured to produce a working fluid that is in a supercritical state or a subcritical state;
• a storage unit configured to store materials including a main material and an auxiliary material different from the main material;
• a dissolving unit into which the working fluid and the materials are fed, the dissolving unit configured to dissolve the materials in the working fluid;
• a mixer configured to mix the materials together in the presence of the working fluid;
• material feed valves each configured to open or close a flow passage through which one of the materials is to pass to be fed from the storage unit into the dissolving unit;
• a working fluid inflow valve configured to open or close a flow passage through which the working fluid is to pass to flow into the dissolving unit from the production unit;
• a mixer inflow valve configured to open or close a flow passage through which the working fluid and the materials are to pass to flow into the mixer from the dissolving unit;
• and
• a control unit for setting pressures in the production unit and the mixer such that the working fluid is kept in the supercritical or subcritical state, and for setting a pressure in the dissolving unit lower than the pressures in the production unit and the mixer.