Flue gas reheating system and flue gas reheating method with online desalting function

The invention relates to a flue gas reheating system and a flue gas reheating method with an online desalting function. The system comprises a circular washing pool, a wet process washing tower arranged above the circular washing pool, a first reheating evaporating tower and a second reheating evaporating tower, the lower ends of which communicate to the wet process washing tower, a purified fluegas adjusting tower communicating to the upper ends of the first reheating evaporating tower and the second reheating evaporating tower and a direct discharge flue arranged above the purified flue gasadjusting tower. An incineration flue gas inlet is formed in one side of the lower part of the wet process washing tower. The flue gas reheating system and the flue gas reheating method achieve a condition creatively that the salt concentration of high salt waste water is reduced to achieve online desalting in a system, and meanwhile, it is ensured that flue gas emission reaches the standard, white smoke plume is eliminat