The PureSOx exhaust gas cleaning system is a combined wet scrubbing system able to operate on sea water (open loop) and fresh water (closed loop). At open sea, the system operates on sea water and saves the use of NaOH and fresh water. In harbours and estuaries with strict discharge criteria, the system is able to operate on fresh water in a closed loop system. This way, the combined PureSOx system offers maximum flexibility combined with low operational costs.
During the first stage of the scrubbing process, the heat in the up to 350°C exhaust gas is utilised by cooling it to 160-180°C in an exhaust gas economiser (optional) as opposed to just wasting the heat. During the second stage, the exhaust gas is treated in a special ejector where it is further cooled by injection of water and where the majority of the soot particles in the exhaust gas will be removed. During the third stage, the exhaust gas is led through an absorption duct where it is sprayed with water and thus cleaned of the remaining sulphur dioxide.
