Krones Celcare offers cellulose-based alternative filter aid

Fig. 1: Krones Celcare filtration system

Filtration is the last step of the beer brewing process to ensure a brilliant, clear product and high microbiological stability. Over 90% of breweries rely on pre-coat filtration using kieselguhr, also known as diatomite or diatomaceous earth (derived from either saltwater or freshwater) as its filter aid. While kieselguhr offers many advantages, it also has some distinct disadvantages, especially in relation to disposal, prompting manufacturers to search for unique solutions. The two new additions to the portfolio are the Phoebus membrane filtration system and the pre-coat filtration system. Both systems have been available for sale since early last year and are now market-ready.

At the heart of this process lies a compressible filter aid developed by Krones, sold by KIC Krones under the name Celcare. For the initial pre-coating, 100% cellulose fibres are used. In the second precoating and in the body feed, a combination of cellulose and perlite are used. Both materials are combined in various amounts and at various degrees of fineness. In order to achieve the desired degree of separation (and ultimately clarity or brightness), the filter cake has to be compressed in a controlled manner. Hence the process technology experts at Krones’ Steinecker plant have developed a way to accomplish just that. A bypass is used to maintain the necessary differential pressure by circulating filtrate back into the un-filtrate feed (ref. to Fig. 1). During filtration, the dosage of Celcare is reduced considerably once the initial “precoating” stage of rapidly building up the filter cake has been completed. In practical terms, this means the longer the filter has been in use, the less filter aid needs to be added.

A sustainable alternative filter aid

Not only does Krones meet economic standards, it also performs well in terms of sustainability and quality.

Cellulose is a natural, renewable raw material that is biodegradable and easily disposed after use. In addition, on-going studies are carried out to see if they can be used in biogas plants. Beer quality achieved using Krones’ Celcare precoat filtration matches with that using kieselguhr. In general, all breweries which use TFS* filters can be retrofitted to work with Celcare. Third-party candle filters can also be converted to TFS* technology.

As with all things, teamwork is paramount. While the experts from House of Krones collaborate closely on the implementation, the Steinecker plant process technology specialists make necessary adjustments to the controls and the filter. This means not only adding an inductive flow and a control valve to the filtrate line, it also means a constant flow of filtrate independent of the output of the pump used to regulate differential pressure.

Breweries may learn more about Krones Celcare filter aid from consumable specialist, KIC Krones, whose experienced team can answer any queries brewers may have on the different aspects of keeping machines and lines well-supplied.

Beer filtration using Krones Celcare system

Filtration principle

Precoat filtration using a compressible filter cake based on the filter aid Krones Celcare

 

Filter aid

  • Cellulose fibres for the initial precoat
  • A combination of cellulose fibres and perlite for the second precoat and body feed

 

Flexibility to respond to the beer’s filterability

 

Continuous adjustment of the dosage of Celcare in the body feed to enable flexible response to the quality of the unfiltrate

 

Filtration cycle

12 to 14 hours

 

Disposal of filter aid

  • Fertiliser
  • Landfill
  • Potential use in biogas plants (currently under testing)

 

Water/media/energy consumption    

Comparable to kieselguhr

 

 


 

 

 

 

 

 

 

 

 

 

Fig. 2 Summary table



*TFS = Twin Flow System technology