A comparative study of 4 different types of full-scale sludge dewatering units was performed in 1990 by I. Krüger AS in co-operation with the equipment suppliers.
The purpose of the study was to examine the capability of the dewatering equipment on the “new” sludge types from wastewater treatment plants with N and P removal.
The achieved results have formed the basis of a financial evaluation comprising construction and operating costs. The objective of the evaluation is to compare the total costs involved in sludge dewatering and disposal.
The relatively cheap types of dewatering units (belt filter press, solid bowl centrifuge) produce dewatered sludge with a lower dry solids content than the more expensive equipment (press centrifuge, membrane filter press).
The latter types should consequently primarily be applied where the dewatered sludge has to meet special requirements and in situations in which disposal costs are very high.