Sludge management is one of the most significant operational and cost challenges in wastewater treatment. The volume of sludge generated by biological and chemical treatment processes is substantial, and disposing of it in liquid or semi-liquid form is expensive and logistically difficult. Filter presses address this by reducing sludge volume through dewatering, producing a dry, manageable cake that is far cheaper and simpler to handle and dispose of.

The filter press operates by pumping sludge under pressure into a series of chambers formed between filter plates. Water is forced through filter cloths lining the chambers while solids are retained, building up as a cake between the plates. When the chambers are full of cake, the press opens and the cake is discharged for collection and disposal.

The dry solids content of the cake depends on the sludge characteristics, the filter cloth specification, and the applied pressure. Filter presses generally achieve among the highest cake dryness of any mechanical dewatering technology, which directly translates to lower disposal costs and reduced transport volumes.

Available in manual, semi-automatic, and fully automatic configurations, filter presses can be matched to the sludge volumes and staffing levels of each facility. Automatic presses complete the filter, open, discharge, and re-close cycle without operator involvement, making them suitable for facilities where labour availability is limited.

Filter presses handle a wide range of sludge types, from municipal sewage sludge to industrial process sludge and chemical sludge from water treatment. Correct polymer conditioning of the sludge before pressing improves cake dryness and reduces cycle times, and Emvees can advise on conditioning requirements as part of the overall dewatering system design.