PURPOSE: To provide a function as an oxydizing device to a falling pipe, in a wet waste gas desulfurization apparatus equipped with the falling pipe for transferring an absorbent slurry containing a Ca-compound to an absorbing part recirculation tank, by providing an air supply means and a gas-liquid contact means to the falling pipe.
CONSTITUTION: The absorbing liquid sprayed from the spray nozzles 22 of an absorbing part 35 is passed through a screen 66 to absorb SOx in exhaust gas and collected in a receiving container 33 and subsequently collected in an absorbing liquid sump 45. Then, the absorbing liquid passes through a falling pipe 40 to be fallen to an absorbing part recirculation tank 38. At this time, air is sucked in the falling pipe 40 from the oxidizing air take-in pipe 41 mounted to a throat part 60 by ejector effect. Because this air is changed in a flow speed by an orifice 41, the gas and the liquid are sufficiently mixed and a part of Ca-sulfite is oxidized in the falling pipe 40 to form gypsum and the absorbing liquid is flowed in the absorbing part recirculation tank 37 along with oxidizing air.
MASUTOMI HIROSHI
NAKAMOTO TAKANORI
