Lesson 9 - Clarification – Filtration SAQ
This lesson allows you to test yourself on the material covered in the Clarification – Filtration lesson, and determine the level to which you have met the learning outcomes.
Suggested Response - Q4
**Answer ALL parts of this question:
You have been asked to scope a project to install a crossflow filter and the different options available to the brewer.
a) What types of beer membrane filters would you consider?
b) How would you expect the changes to impact on filtration performance and labour demands?
c) What benefits would you expect to see, both operational and financial?
Response:
Crossflow filter construction comes in two main forms, polyether sulfone (PES) or ceramic. In both formats, multiple filters are arranged in tubes as a series of bundles within cassettes, which are connected in series. PES is a well-established cross-filter technology, and there are a number of different manufacturers who can supply a brewer.
Ceramic beer membrane filtration is still in its infancy in comparison; however, early indications have shown that it could perform better than PES due to superior micro, haze, β-glucan, and polyphenol reduction capability, in the beer. The only caveat is that pressure and temperature shocks need to be avoided in a ceramic filtration system as the ceramic structure could crack or fracture under these conditions.
There are a number of positive changes a brewer would expect to see:
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Lower operating expenditure as there is no need for DE.
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Lower beer losses as there is no residual beer in the spent kieselguhr at the end of filtration.
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Little operator intervention required – this is ‘black box’ technology; in other words, this is controlled effectively by automation.
In addition, there are a number of sustainability, quality, safety, and corporate image benefits that the brewer would expect to see, these include:
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There would be no spent kieselguhr disposal costs.
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There would be no need for DE storage, handling or logistics required.
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Trap filter would not be necessary as membrane filters are permanent barriers to microorganisms (unfiltered beer is pumped across a 0.45–0.65 μm membrane).
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A sustainable method of filtration – lower water usage, lower carbon footprint and no process aids required.
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Due to the core principle of crossflow, there will be an ability to filter a product with both a high percentage of malt (> 75%) and a product brewed with low-quality malt (wort β-glucans greater than 100 mg/L) which would likely block a DE filter.