Aqueous suspension of milk lime is fed to the first chlorination reactor of type cooled jacket reactor with internal impeller. Temperature of reaction is kept constant by externally supplied coolant.Consumption of wet chlorine is controlled to achieve desired conversion rate of suspension. The reacted sludge is discharged from first reactor and dewatered in solid liquid separation to eliminate mother liquor rich in chlorides from concentrated suspension containing majority of Calcium Hypochlorite. Suspension is than diluted in water and sodium hypochlorite originating from continuous conversion of concentrated caustic and chlorine to high strength sodium chlorite with low sodium chloride content.New suspension is led to the second chlorination stage reactor where the complete conversion of sludge to desired product take place. Process is again operated at low temperatures until desired conversion is reached. Due to low sodium addition high purity product can be achieved even from less pure feedstock materials.Filtered sludge is dried at low temperature end fed into dryer operated at low temperatures to avoid product decomposition. Filtrate rich in product is fed back into the first reaction to increase product recovery yield.Final product is obtained either as granulates or tablets.
Ca-Hypochlorite is the main active ingredient of commercial products called bleaching powder, chlorine powder, or chlorinated lime as algicide, bactericide, fungicide is employed as a disinfectant and deodorant in treating water. Is excellent oxidizing and bleaching agent.Its major advantage is high content of active chlorine in sold form, long shelf lifetime and long operating radius. Is used to disinfect waters, swimming pools or equipment. Important for this plant is availability of chlorine and high-quality calcium hydroxide (eventually CaO).
Main auxiliaries needed that we normally do not include
Electtrochimica Solfuri (Today Solvay)