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Wet End Industrial Filtration facts

Any oversized, undissolved solids in an additive stream have the potential to interrupt equipment operation or create dry end defects. Unfortunately, many opportunities exist for solids to be picked up or formed as additives are transported, mixed, or diluted.

Consequently, wet end additive filtration can help minimize process variability.Where filters are used in the wet end depends on the original engineering of the paper machine and is modified as the process and products change over time. Filters are added when particles affect the delivery of the additive or the quality of the end product. Flow rate, media type, particle retention, and the characteristics of the additive and its debris will dictate the type of filter most appropriate for additive filtration.

Continuous multiple tube filters or multiple bag filters are often recommended in the receiving area due to higher flow rates. However, the flow rates are relatively low at an additive point of use. Mechanically cleaned-in-place filters can, therefore, be used as an additive",s point of use since they can maintain a low differential pressure and also prevent contamination extrusion through the media. It is important to keep the differential pressure low for retention aids, to prevent gel-like contaminants from squeezing through the screen. Mechanically clean-in-place filters clean the filter media before any pressure buildup occurs.