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The challenges of beer microfiltration are fouling and to get decent quality. These problems can be partially eliminated with the use of Static Turbulence Promoter (STP). In this study, STP (pitch diameter ratio of 2, 13.2 mm pitch length, 6.5 mm diameter, 241 mm length, and 1.2 mm thickness), Pall Membralox T1‐70 membrane, and lager beer were used for the filtrations. Experiments were performed with combinations of different parameters, such as usage of STP (No/Yes), Transmembrane Pressure (TMP) (0.4–1.2 bar), and Retentate Flow Rate (Q) (50–200 L hr−1). Experiments were ranked with Sum of Ranking Differences based on the analytical properties, hydrodynamic and separation characteristics parameters. The best conditions were the following: STP = Yes, TMP = 0.4 bar, Q = 50 L hr−1; STP = No, TMP = 0.4 bar, Q = 200 L hr−1; STP = Yes, TMP = 1.2 bar, Q = 200 L hr−1. Practical applications Clarification of rough beer is important because of eliminating yeast and colloidal particles responsible for haze and ensuring the microbiological stability of beer. Our research has several practical applications as mentioned below. First clarification of rough beer by crossflow microfiltration is more sustainable technology than conventional clarification with Kieselguhr, because of lower carbon footprint, lower solid waste stream, less beer loss, and less health and safety concerns. In addition, the shelf life of the microfiltered beer is longer, because there is no iron pickup. Furthermore, according to the results better beer quality can be achieved with the application of novel Static Turbulence Promoter (STP) compared to the conventional (without STP) membrane filtration. It is important because product quality is partly responsible for consumer satisfaction. Finally, it has been proven that usage of STP can improve filtration throughput that means lower production cost.

Oily wastewaters are produced in large amounts in many fields of food, mechanical, and other types of industry. In order to protect the environment, wastewaters must not be discharged directly into sewers. First, they must be cleaned at least down to 50 mg L−1 of oil content (according to Hungarian standard). In previous research, the authors found that oil-in-water emulsions can be separated with filtration using ceramic ultrafiltration tubular membranes. The relatively high price of ceramic membranes can be compensated by the fact that this separation process can be significantly intensified by static mixers inside the tubular membranes. New generations of ceramic membranes are the ceramic capillary membranes. These two different types of membranes and their effects on permeate flux, oil retention and specific energy consumption were compared in this work. The results, obtained with a stable oil-in-water emulsion as feed, showed that the use of novel ceramic capillary membranes at optimal operating cross-flow rate and transmembrane pressure is reasonable. The results have also shown the advantage of static mixing in the lumen side of the membrane tube providing a wider range of satisfactory separation level and increased permeate flux.

Membrane chromatography (MC) is an emerging bioseparation technology combining the principles of membrane filtration and chromatography. In this process, one type of molecule is adsorbed in the stationary phase, whereas the other type of molecule is passed through the membrane pores without affecting the adsorbed molecule. In subsequent the step, the adsorbed molecule is recovered by an elution buffer with a unique ionic strength and pH. Functionalized microfiltration membranes are usually used in radial flow, axial flow, and lateral flow membrane modules in MC systems. In the MC process, the transport of a solute to a stationary phase is mainly achieved through convection and minimum pore diffusion. Therefore, mass transfer resistance and pressure drop become insignificant. Other characteristics of MC systems are a minimum clogging tendency in the stationary phase, the capability of operating with a high mobile phase flow rate, and the disposable (short term) application of stationary phase. The development and application of MC systems for the fractionation of individual proteins from whey for investigation and industrial-scale production are promising. A significant income from individual whey proteins together with the marketing of dairy foods may provide a new commercial outlook in dairy industry. In this review, information about the development of a MC system and its applications for the fractionation of individual protein from whey are presented in comprehensive manner.

Membrane filtration process can be intensified by using static mixers inside tubular membranes. Most of commercial static mixers are optimized for mixing fluids, not for membrane filtration. We have developed new turbulence promoter geometries designed for intensification of permeate flux and retention without significant pressure drop along the membrane. In previous experiments, we used metallic turbulence promoters, but in this work, FDM 3D printing technology was used to create these improved geometries, which are new in membrane filtration and they have the same geometry as existing metallic versions. New 3D printed objects were tested with filtration of stable oil-in-water emulsion. Our experiments proved that 3D printed static mixers might be as effective as metallic versions. The effect on initial flux and retention of oil was very similar. Pressure drop along membrane was slightly higher (but significantly lower from pressure drop along the membrane resulted by commercial static mixers, designed only for mixing fluids). Higher pressure drop may be the result of rougher surface due the layer-technology of 3D printing. This negative effect can be reduced by using a smaller nozzle (which will produce smaller layers) or smoothing the surface. PLA is material easier for printing, but from these two materials, PETG is a better choice due its higher operating temperature and better water-resist properties too.