(57) An absorbing liquid extracted from an absorbing tower tank 5 of an absorbing tower 1 is transferred to flow into a slurry tank 9 by means of a first pump 8. A separating device 2 separates the absorbing liquid transferred from the slurry tank 9 by means of the second pump 10 into gypsum and a dehydrated filtrate. A filtrate recovery conduit 20 provides communication between a filtrate outlet 40 and a filtrate inlet 41. The filtrate outlet 40 has a ground height He greater than a ground height Ha of the filtrate inlet 41. The filtrate recovery conduit 20 is disposed such that the dehydrated filtrate that has flowed out of the filtrate outlet 40 can flow down due to gravity and flow into the filtrate inlet 41.
(71) Mitsubishi Hitachi Power Systems, Ltd., Kanagawa (JP)