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Now that we have discussed the role of the recausticizing system in the kraft pulping process, we will detail the system equipment and operations, starting with the green liquor clarifier and ending at the lime kiln. The green liquor clarifier purifies the green liquor from the smelt dissolving tank before it enters the recaust system. A sedimentation clarifier is typically used. A sedimentation clarifier is a tank or basin that provides the time necessary for suspended solids in a liquid to settle out. The small solid particles that are suspended in the green liquor are called dregs. Once the dregs have settled out, they can be removed from the bottom of the clarifier by a rake mechanism and center sludge outlet. After the clarifier, the dregs are washed and filtered on the dregs filter, which recovers most of the valuable cooking chemicals they contain. Finally, they are discharged from the system as waste.