| 摘要 |
A method for treating impurities contained in exhaust gases of ships to reduce sulphur oxide and other emissions, includes scrubbing the exhaust gases in an exhaust gas scrubber and supplying wash water effluent exiting from the scrubber and containing impurities to a purification unit onboard a ship. In order for the method to purify wash water exiting the scrubber sufficiently enough to be discharged directly to sea, the purification unit includes a moving filter band, whereby an aqueous fluid containing impurities originating from the effluent is together with a precipitating agent fed to a surface of the inclined filter band and filtered there through to concentrate impurities onto the surface of the band filter as a precipitate. When necessary, the pH of the purified effluent is adjusted so that it is at least 6.5 before discharging the purified effluent into the sea or returning it to the exhaust gas scrubber. |
