抄録
At the conventional production method of emulsion fuel, it was very difficult to mix water into oil minutely and homogeneously, which means that combustion of emulsion fuel was unstable and not able to use it as fuel for a diesel engine. It was mainly due to the lack of agitation ability for high quality emulsion fuel. Therefore, the production tests for the minute, homogeneous and water in oil type emulsion fuel were tried, by the method of using strong diffusion ability of ultrasonic cavitation. High shock wave area is created between the ultrasonic transducer horn and the reflector, both of which are immersed in the water. The test was executed by the method to agitate water and the fuel in this high shock wave area. The test equipment consists of ultrasonic transducer, mixing tank, metering pump and pipe structure. Then, fixed quantity of fuel and water were supplied to mixing tank. Gas oil and fuel oil were used as the test material oil and a small quantity of emulsifying agent was dissolved in the fuel, beforehand. Tap water was used as water material and mixed into oil with three kinds of volume ratio. The aimed quality was that emulsion fuel is water in oil type, submicron size homogeneous water, and its continuous stable period for five days. For the measurement of the water particle diameter, the light microscope, the electron microscope, and dynamic light scattering method were used. The deterioration of emulsified fuel was checked by observing the test liquid in the sample bottle at stable condition. The water particle diameter was measured with three kinds of different measurement method. And, it was confirmed that the diameter was approximately 0.2μm or less. The quality of emulsified fuel was maintained for five days or more, in all mixing test. As the result of our development, the technology to agitate water and oil minutely and homogeneously were developed and established, by the method of creating high shock wave between the ultrasonic transducer horn and reflector and adjusting the gap and liquid volume. It became possible to produce high quality emulsion fuel continuously, which can be used as fuel for diesel engine.
