从节能、空气污染和外燃系统总体运行成本的角度分析了使用水-燃油乳剂的优缺点。在恒定过量空气水平下将水与燃油混合用于外部燃烧具有以下优点:由于绝热火焰温度较低，减少火焰产生烟雾（烟灰）的趋势，并降低NOx排放水平，但缺点是:由于部分燃料能量现在用于蒸发水，因此降低了燃烧效率。可能增加燃料装卸设备的腐蚀。 发现烟囱露点温度的变化小于燃料类型或硫含量变化引起的变化。如果从能量角度来看，过量空气减少了盈亏平衡所需的量，如图所示:烟雾水平通常与加水前相似，NOx水平略低。燃烧效率没有提高（盈亏平衡点），但乳化设备的摊销将增加总运营成本/加热季节。如果过量空气的减少量大于盈亏平衡所需的量，燃烧效率将提高。 结果表明，如果加水量为20%或以上，则不太可能发生这种情况，除非燃烧设备未处于适当的工作状态，例如空气过量超过50%和/或烟囱温度过高。需要开展研究工作，以确定在可比较的烟囱烟尘质量负荷下，水添加量对传热表面污垢的长期影响。引文:伊利诺伊州芝加哥ASHRAE Transactions第83卷第1部分

The advantages and disadvantages of using water-fuel oil emulsions have been analyzed from energy conservation, air pollution and overall operating cost points of view in external combustion systems.Mixing water with fuel oil for external combustion at constant excess air level has the advantage of:Reducing the tendency of the flames to generate smoke (soot) andReducing the level of NOxemission because of the lower adiabatic flame temperature,but has the disadvantage of:Reducing the combustion efficiency since part of the fuel energy is now used to vaporize water.Potentially increasing the corrosion of fuel handling equipment. Changes in stack dew point temperature were found to be less than those caused by changes in fuel type or its sulfur content.If the excess air is reduced by amounts required to break even from an energy point of view, as calculated and presented here in graphs:The smoke level will generally be similar and the NOxlevel somewhat lower to what they were before adding water.No gains in combustion efficiency will have been made (break-even point), but amortization of the emulsification equipment will increase total operating costs/heating season.If the excess air can be reduced by amounts larger than those required to break even, combustion efficiency will be increased.It is shown that this is not likely to happen with water additions of 20% or more unless the combustion equipment was not in proper operating condition, such as represented by excess air levels above 50% and/or high stack temperatures.Research work is needed to determine the long term effects on heat transfer surface fouling as a function of water additions, under comparable stack soot mass loading.