The flue gas passes the untreated side of GGH and is cooled through the heat exchange with the outlet flue gas from the wet scrubber. After that, the flue gas will enter the flue gas scrubber. The scrubber is composed of two parts, the cooling end and the absorption dehumidifying end.

In the cooling end, the flue gas temperature is cooled from about 100℃ to about 60℃ by spraying cooling liquid from the top of the cooling end into the flue gas. Absorbent is injected into the cooling liquid. After adjusting to an appropriate pH value, the cooling liquid can absorb the hydrogen chloride and sulfur oxides in the flue gas.

In the treated side of GGH, the water saturated flue gas from the scrubber conducts heat exchange with the flue gas at the inlet of the wet scrubber. The flue gas is emitted from the stack after being heated to the acid dew point.