Continuous beer filtration technology with regenerable-aids : identification and analysis of critical parameters

Details

Supervisors

Collin, Sonia ; Declerck, Christophe

Faculty

Faculté des bioingénieurs

Degree label

Master de spécialisation en génie brassicole

Abstract

The replacement of kieselguhr as filtration aid in the brewing industry has already been the subject of much investigation that have led to different innovative ways of improving. One of them is the IFT filtration technology developed by AB-InBev. The goal of this thesis is to identify and to improve the operating conditions of the IFT filtration line used at AB-InBev in Leuven (Belgium). To achieve this work, down-, on- and up-stream parameters regarding the overall filtration process have been considered in order to find how these could impact the efficiency of this regenerable-aid technology. Therefore a lot of industrial trials have been achieved with three different beers, and correlations between some relevant parameters have been established. The consistency of Darcy’s law for IFT cake filtration was verified, with some differences from one beer to another. Similarly, the average specific cake resistance and the resistance related to the medium+precoat has been determined and were consistent with Sutherland and Hidi’s linear model as well as with the results from Brocheton and al. [1]. Furthermore, at industrial scale, the present beer model for pressure growth has been improved by using a progressive incremental flow mechanism. This new setting allowed to reduce pressure jumps caused by low to high flowrate transitions, occurring at the beginning of the filtration process. Statistical analyses were used to find correlations between process and quality parameters, and a major output is that a combined dosing algorithm for brewtan and MIX, which are currently operating independently, should be used to avoid early termination of the filtration cycle. It also appeared that effective filtration time length is reduced by either Bwt overdosage, either high pressure growth, because both parameters cause a recirculation of the beer onto the filter. By performing a weekly acid CIP of the IFT filtration line, 1 hour of filtration time was gained right after the cleaning of the filter. To decrease MIX and time losses related to the hot skimming process, its frequency of operation was reduced from one per three to one per ten filtration cycle, at the end of which only 5hL were sent to the drain.