In this work, we formulate a simple one-dimensional model as a framework for studying the influence of water-in-fuel emulsions on spray diffusion flames. The special contribution of these emulsions to combustion is examined via the relevant steady state equations, which are solved both analytically, when the chemical Damköhler number becomes infinitely large, and numerically when it is finite. Two possible scenarios are investigated; the first, when no micro-explosions occur. The second is when conditions are met for droplet micro-explosions to happen, an occurrence that has been independently observed. The leading order analytical solutions indicate that, as far as the fuel vapour and temperature profiles are concerned, any differences between the case of occurrence and non-occurrence of micro-explosions is fairly minor. However, the numerical solutions showed that in both scenarios the range of permissible values of supply stream mass flux for which spray diffusion flames can be established is considerably reduced by the presence of the water in the droplets. This effect is magnified greatly when micro-explosions take place, primarily due to the focused heat loss for droplet evaporation which entails as the water vapour is released and the evaporation rate of the small droplets created by the micro-explosions is enhanced.