Dry waste gas cleaning apparatus for saving cooling water

摘要

The present invention relates to a cooling water-saving apparatus for washing dried flue gas, wherein after dried flue gas is washed twice, the treated water used in first and second washing will be used again in washing, thereby saving cooling water used in washing of dried flue gas. The apparatus of the present invention comprises: a first water storage tank (10) supplying water to a first washing portion (50) and receiving second treated water discharged from the first washing portion (50) to supply the same to a treated water mixing tank (100); a second water storage tank (30) receiving dried flue gas discharged from a second washing portion (60) to discharge the dried flue gas outside and receiving the first treated water to supply the first treated water to the treated water mixing tank (100); a treated gas discharge portion (40) discharging the dried flue gas introduced into the second water storage tank (30) outside; a first washing portion (50) receiving and elevating the dried flue gas of the first water storage tank (10) introduced through from the lower end thereof to spray mixed treated water and perform first washing and then, after washing, discharging the second treated water into the first water storage tank (10); a second washing portion (60) lowering the one time-washed dried flue gas discharged through the upper end of the first washing portion (50) and spraying outer cooling water to perform second washing and then, after washing, discharging the first treated water to the second water storage tank (30); a treated water mixing tank (100) receiving the second treated water stored in the first water storage tank (10) and the first treated water stored in the second water storage tank respectively to mix them; and a controller (90) controlling the second treated water and the inflow thereof in order to control the temperature of the mixed treated water stored in the second water storage tank (30) to be a predetermined temperature.