| The need of fuel increases sharply and the regulation environment and energy savingaugment more and more at the same time with the development of industry andeconomy. However, The quality of heavy oil descends owing to its high asphaltene and manynitrogen and sulfur with the development of modern petroleum processing technologies. Theircombustion leads to the formation of nitrogen oxides and sulfur dioxide andparticulates, which aggravate environmental problems. The emulsified fuels become aneffective method for solving those problems due to the shortage of oil resource and pollutionof the environment.The aim of this research is to decrease fuel consumption and lessen NOx, SO2 andparticulates by using emulsified heavy oil. The mechanism of fuel saving and emissionreduction were discussed in this paper. Based on surface chemistry, proper emulsifiers wereselected to produce stable and Nano-emulsion heavy oil, which contains different amount ofwater. The characters of emulsified fuel such as viscosity, surface tension, heat value andstability were analyzed.The TEM and electrical conductivity measurement show that the structures ofNano-emulsion is oil -in- water (O/W), the interface of water and oil is clear, and thediameter is 20～50 nm. The viscosity increases only a little bit more than the original one,and dereases tardily with the content of water. This product can exist stably for more than 10months and will not demulsify even under 80 C for 3 days.The evaluation result by oxygenbomb test indicates that the combustion performance of the heavy oil is promoted to certainextent.When the amount of water admixed with heavy oil is from 3％to 12％, increaingcombustion efficiency to 2.5％～6.1％. The repeating experiments show that with theincrease of water content from 3％to 20％, SO2 decreased gradually at a maximum reductionrate of 22.2％, NOx decreased by 15.3％.For improving the combustion complete degree of heavy oil, CeO2 nanocatalyzer weresynthesized by the sol-gel method,and doped Zn, Zr in the CeO2. The effect of the amount ofdoped Zn, Zr on the microstructure of CeO2 was studied by the XRD, SEM and BET. In ourexperiments, small amount of additive was mixed with emulsified heavy oil to investigate theeffect on the combustion performance of emulsified heavy oil. It was showed that Nano-CeO2can reduce SO2 and NOx emission largely. When the amount of CeO2 admixed with heavy oilis 0.2％, the emission of SO2 and NOx decreased by 24％and 62％respectively. The effects ofcontent Zn and Zr in the catalyst and combustion performance of heavy oil wereinvestigated, The results indicate that a small quantity doped Zn, Zr exhibits high activity inlessening NOx and SO2.
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