Many filling and bottling operations clarify their products immediately prior to filling using filters from Delta Pure Filtration. On the one hand, placing a properly selected filter at the very end of a process line assures that accidental contamination, such as from a worn valve seat, is removed. On the other hand, a filter right next to a bottling machine might be exposed to damaging pressure cycling. This article gives some ideas on how to select and use filters for bottling operations.
Delta Pure Filtration offers filters to remove a variety of contaminants, including particles, microbes, organics and chlorine. The attached chart shows some of the filtration objectives and filter types used. (These are generalizations and filters should be selected and tested on a case-by-case basis.)
|Objective||Suggested Micron Rating||Typical Filter Type|
|Clarify by filtering out visible particles to produce a clear, sediment free solution.||40 microns or finer||PPA Series pleated filterMB series polypropylene melt blown filter|
|Remove haze from cosmetics and toiletries to create a pleasing customer experience.||0.5 micron to 5 micron||MB series polypropylene melt blown filter|
|Microbially stabilize a beverage to improve shelf life.||0.2 nominal to 1 micron absolute||PPA series pleated filter|
|Remove chlorine and/or many types of organics to improve taste, purity, etc.||Carbon filter||CCB, DCB, DWCF, CN04, and CN04CF Series|
Hopefully any bottling unit will have a surge or buffer tank! Bottling can be “start-stop” and the average flow rate can be significantly less than the instantaneous demand. In addition, start-stop operation can cause water hammer or pressure cycling that can damage a filter vessel or filter. A surge tank or buffer tank lowers the flow rate that a filter needs to handle from the “maximum instantaneous flow” to the average need, and the air cushion at the top of a surge tank protects a filter assembly against pressure surges.Filling machines sometimes have washing units upstream of the product filling operation. The wash fluid, (such as water) will be filtered as well.
We recommend that when selecting a filter assembly for a bottling operation, that the system designer carefully ascertain the various types of flows and pressures involved (average, maximum, etc.) for both current and future requirements. It is also important to review a sketch of the bottling operation showing the location of the filter assembly relative to upstream and downstream equipment such as buffer tanks, pressure dampeners, filling unit, etc. There are various strategies for allowing for future growth – two examples are over-sizing, and selection of a housing that can accept filters of multiple lengths.