The PENTA filter

The sludge removal and filtering system

In the manufacturing process of stainless steel there it produces an oxide layer (scales) on the surface of the material. For the material to have the correct properties this oxide layer must be removed. This is done both by mechanical and chemical processes. The remaining oxide scale left after the mechanical process is removed by acid (often mixed acid HF/HNO3). The chemicals dissolve the surface of the steel and releases the oxide scales. A part of the oxide scale dissolves in the acid and the remaining part (often the main part) gathering as undissolved particles that creates suspended solids (sludge).

Luova has develop the PENTA by adapted the FUNDABAC © filtering principle to continuously remove all particles from the pickling solution in the pickling line. Together with one of the leading manufacturers on filter media we can equip the PENTA with a wide range of filter cloths (PE, PP, PVDF and even in Gore®) to suit any task.

Inside the PENTA filter chamber there are five (5) PVDF plastic candles. On each candle there is a filter cloth mounted. The acid is directly fed to the PENTA from the pickling tank or via an optional receiver tank. A pump fills the filter chamber with the acid. The special design allows a high flow of acid through the filter cloth and into the candles clean acid outlet. The sludge sticks on the filter cloth and starting to build a filter cake. After some time when the filter cake is starting to get thick the clean flow will decrease and the PENTA will automatically dispose of the sludge and clean the filters.

  • For sludge “free” pickling conditions
  • High capacity sludge removal with minimal acid losses
  • Clean acid flow up to 2000-3000 l/h
  • Automatic de-sludge and filter cleaning cycle
  • Several filter media (cloths) available for different application
  • Compact foot print

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