Liquid ammonia desulfurization is a new and most advanced desulfurization method with high desulfurization rate. It can produce ammonium sulfate fertilizer, and the income and expenditure are basically balanced, but the initial construction cost and operation cost are high. Compared with calcium desulfurization, ammonia desulfurization process is not mature, and it has been a widely used desulfurization technology. At present, the better ammonia desulfurization companies in China are Luoyang Tianyu and Jiangnan Environmental Protection. The process principle is as follows:
Ammonia water contacts with flue gas through spraying, absorbs sulfur dioxide in flue gas, and finally generates ammonium sulfite. The reaction formula is as follows:
SO2+NH3+H2O=NH4HSO3 ( 1)
SO2+2NH3+H2O=(NH4)2SO3 (2)
SO2+(NH4)2SO3+H2O=2NH4HSO3 (3)
NH3+ NH4HSO3=(NH4)2SO3 (4)