Abstract :
Results are presented of a theoretical study to assess the viability of using water-in-oil emulsions for power-station boilers to reduce pollutant emissions, deposit buildup on heat-transfer surfaces and excess-air requirements while improving boiler efficiency. The variables studied include the water concentration (0–10%) and percentage of maximum output (40–100%). SOx and NOx emissions are reduced by 20 and 5.5 kg/h, respectively. The dirt factor of the water-wall tubes drops by 27% without a significant change in the tube temperature. The excess-air coefficient is reduced by 13% and the boiler efficiency is increased by 0.75%. The maximum gas-temperature rise and decrease along the boiler pass are not, vert, similar +50 and not, vert, similar −5K, respectively, as the water concentration is increased from 0 to 10%.
