Measurement of diameter distribution of dispersed droplets in W/O emulsified fuel and the effect of emulsified fuels on boiler performance

In this study, we measure diameter distribution of dispersed water droplets in the W/O emulsified fuels with 10 and 20vol.% of water. Then, the emulsified fuel was applied to 233kW oil-fired water heater. The exhaust gas concentration of NO_x, CO and SO_x, and the thermal efficiency were measured under high and low combustion load. With an increases in the water content, both exhaust NO_x and CO concentration decreases under both high and low combustion load. In high combustion load, the thermal efficiency increases as the water content increases. However, the thermal efficiency decreases under low combustion load because of latent heat of vaporization of water contained in the emulsified fuel. Especially, thermal efficiency increases by 12% when 20 vol.% W/O emulsified fuel was used in high combustion load.