Detergent powder manufacturing plant

The liquid effluent leaving the SO2 scrubber consists of a solution of caustic soda, sodium sulphite, sodium sulphate and traces of active matter. At 98% SO2 SO3 conversion (steady-state running conditions) about 80 kg/h of a 10% sodium sulphite solution will leave the scrubber system, based on a 10(X) kg/hr sulphonation plant (see table 19). The alkaline solution is collected in an acid/caustic-resistant pit. It is common practice to dilute this liquid stream with other effluent streams (ex slurry-making and powder manufacture) and to re-use it in the detergent powder manufacturing plant as dilution water. 

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