Flammable solvents can be used in special type of ultrasonic storage tanks for this purpose. Before using a flammable solvent in an ultrasonic system, you should do everything you can to find an unflammable solvent or process. In the design process, a freeboard that is equal to the depth of the liquid in the tank must be built. Other considerations include the condenser coil in the freeboard area, which will allow the vapor to condense from the flammable solvent to keep it from leaving the fuel tank. The fuel tank must also have a sealed transducer box, cleaned with an inert gas. This prevents any spark or other electrical failure from causing any steam that may have reached the area.
