Journal of Food Engineering, Vol.173, 132-142, 2016
Assessment of the optimal operating conditions for pale lager clarification using novel ceramic hollow-fiber membranes
In this work, the lager beer clarification and stabilization process previously developed was further tested by replacing the 0.8-mu m ceramic single-tube membrane module with a novel ceramic hollow-fiber membrane module having the same pore size to offset the known ineffectiveness of back-flushing cleaning techniques in ceramic multi-channel monolithic modules. In total recycle crossflow microfiltration (CFMF) trials, the quasi-steady state permeation flux (J(ss)) tended to a limiting flux (J*), that was found to increased with the crossflow velocity (v(S)) in the range of 0.5-6.0 m s(-1). The ideal hydraulic pump energy consumption per unit liter of permeate recovered was practically independent of the aforementioned operating variables and of the order of (66.5 +/- 0.5) W h L-1. Nevertheless, to obtain a quasi-state state permeation flux greater than the target permeation flux (i.e., 100 L m(-2) h(-1)) for rough beer clarification via membrane processing in the absence of CO2 backpulsing, TMP had to be greater than 2 bar and v(S) to vary from 4 to 6 m s(-1). Not only was the performance of the ceramic hollow-fiber membrane module at 10 degrees C, v(S) = 2.5 m s(-1), and TMP = 2.4 bar with 2-min periods of CO2 back-flushing applied every 50-60 min superior to that of the polymeric hollow-fiber membrane process patented by Heineken and Norit Membrane Technology, but also the use of ceramic hollow-fiber membrane systems would extend the membrane life span up to ten years, this reducing the contribution of the annual membrane replacement to the overall operating costs of beer clarification. (C) 2015 Elsevier Ltd. All rights reserved.
Keywords:Beer clarification;Ceramic hollow-fiber membrane;Crossflow microfiltration;Crossflow velocity;Optimal conditions;Limiting permeation flux;Pale lager;Transmembrane pressure difference