Abstract: A dehumidifying tower having a washing section, a flash-distilling section, and a condensing section. In the washing section, exhaust gas is washed with a cooling liquid to remove at least a portion of solid dust entrained in the exhaust gas, cool the exhaust gas, and condense at least a portion of moisture in the exhaust gas into liquid. The flash-distilling section flash-distills the cooling liquid used in the washing section to produce a cooled cooling liquid and a cooling liquid vapor. Cooling liquid produced by flash-distillation enters the washing section. The flash-distilling section is in gas-phase isolation from the washing section. The condensing section condenses the cooling liquid vapor produced by flash-distillation. The condensing section is configured to be in gas-phase communication with and liquid-phase isolation from the flash-distilling section, and be in both gas-phase and liquid-phase isolation from the washing section.