A Study On The Emulsification Of Diesel Fuel By High Intensity Focused Ultrasound

As a kind of clean energy, emulsified diesel fuel can play an importantrole in energy saving and emission reduction, and it was concerned by manycounties. The emulsion produced by power ultrasound has many advantages.These advantages include smaller droplet, good stability, less emulsifierusing and less energy consumption. The surfactants Span80and Tween80were chosen. The optimum HLB was5.4and the optimum input power was950W. The emulsion viscosity and stability increased with the dosage ofemulsifier. The emulsion viscosity increased with water content, butemulsion became more and more instable with an increase of water. Longerinsonation time induced the emulsion viscosity to increase slightly at first,and then it did not change too much. Insonation time300s could producefine emulsions. The result showed that spherical focused ultrasound setupcould not only provide high energy, but also induce intensive cavitation andstir. The using of high speed photography technology showed that cavitationand interfacial instability also were the main principle of this kind ofemulsification. With optimum HLB value5.4, water could bewell-distributed in diesel and the droplet size was as low as0.5μm. The stabilization time of the emulsion could be more than six months. Comparedwith using insonation equipment with sonotrode and magnetic stirrermethods, the spherical focused ultrasound setup was better both in effect andefficiency. This setup provided a novel and significant way forwater-in-diesel emulsification.