Waste gas collecting device

The utility model discloses a waste gas collecting device. Dispersion tank, the method is characterized in that the method is characterized by comprising the following steps; the top of the dispersiontank is communicated with a spraying dispersion pipe which vertically extends into the bottom in the dispersion tank; the top of the spraying dispersion pipe is positioned on the outer side of the dispersion tank and is communicated with a waste gas conveying pipe; the top of the dispersion tank is communicated with a water inlet pipe; the bottom in the dispersion tank is arranged in a slope manner and is communicated with a blow-off pipe; the dispersion tank is communicated with a circulating pump positioned above the blow-off pipe through a pipeline; the circulating pump is communicated with a heat exchanger through a pipeline, a spraying pipe is arranged at the inner top end of the spraying dispersion pipe, a water feeding pipe which extends into the top of the spraying dispersion pipeand is communicated with