Background

A beverage producer was facing a filtration problem in its apple cider production line. After fermentation and activated carbon treatment, the customer occasionally found fine suspended impurities and small black carbon particles in the liquid. Although the particles were not present in every batch, they affected product appearance and created extra inspection pressure before filling.

Customer Challenge

The customer had tried using a finer filter cartridge at the final filtration point. This helped improve clarity for a short time, but the filter blocked quickly when the upstream impurity load increased. The pressure drop rose faster than expected, and the replacement cost became difficult to control. In some cases, very fine carbon powder still appeared downstream.

Pullner’s Analysis

After reviewing the process, Pullner found that the issue was not caused by filter accuracy alone. The original filtration design relied too much on one final filter. This single filter had to remove fruit pulp residues, yeast sediment, colloidal matter, and carbon powder at the same time. As a result, the final cartridge was easily overloaded.

Staged Filtration Solution

Pullner suggested a staged filtration solution. The first stage used a cost-effective depth filter to remove larger suspended solids and protect the downstream filters. The second stage used a pleated filter cartridge to further reduce fine particles and stabilize the liquid quality before final filtration.

For the final stage, Pullner tested different filter materials, including PP and PES pleated filter cartridges, to compare clarity improvement, carbon powder retention, pressure drop, and flow stability.

Test Result

After on-site testing, the customer selected a more suitable filter combination based on the actual apple cider condition. The optimized filtration arrangement helped reduce visible carbon powder leakage and improved the stability of the final product appearance. The pressure rise became more predictable, and the final filter was no longer overloaded as quickly as before.

Technical Insight

This case shows that beverage filtration is not simply about choosing a smaller micron rating. For apple cider, beer, juice, and other fermented drinks, the source of impurities, carbon treatment process, filter position, material compatibility, flow rate, and replacement cost should all be considered together.

Pullner Filtration Support

Pullner provides filter cartridge solutions for food and beverage applications, including apple cider, beer, juice, syrup, process water, and other liquid filtration processes. By testing different filter materials and designing a reasonable staged filtration system, Pullner helps customers improve filtration stability, protect product quality, and reduce operating costs.

For more information about Pullner food and beverage filter cartridges, please visit www.pullnerfilter.com.