Enhancement of membrane filtration process in dairy technology

The main subject of this project is the investigation of the improvement of membrane filtration processes in dairy industry by application of new developed process, reduction of membrane fouling and enhancement of the process economy.

Membrane separation technology, where ultrafiltration (UF), microfiltration (MF), reverse osmosis (RO), diafiltration (DF) and nanofiltration (NF) are alternatives, can fractionate species of different molecular weight that pass through a semi–permeable membrane, wherein a pressure gradient is applied between both sides of the membrane. This kind of separation-concentration process has been growing up in importance since the 1990s. Industrial development is conditioned by the need of lowering costs, ecological demands and the need of common technologies that are able to combine different unit operations. The four types of module constructions for membrane separations have been developed for commercial applications and practically all have successful application in industrial engineering. In addition to concentration and fractionation of whey and milk, membrane separation has been introduced into industries related to foods, pharmaceuticals, textiles, sea water desalination, and waste water treatment. In general, for further industrial application, the capacity of membrane processes should be increased; appropriate fouling control is also important regarding the economics of the process. Although flux enhancement has got a lot of attention in terms of understanding and practical improvement (with insert and back pulsing), achievement of a high selectivity (full retention of large components and full transmission of small ones) deserves more attention. Membrane filtration is carried out in different module configurations, such as plate and frame, hollow fibre, spiral wound and tubular. Each type of module consist of membranes whose characteristics determine the processing efficiency. Particularly important membrane characteristics include pore size, pore–size distribution and type of macromolecular material of which the membrane is composed. Current membrane processes for milk have a rather low capacity due to strong flux decline by fouling, or processes are energy demanding because of the high cross flow velocity that is required to control fouling. In addition, methods to control fouling have increased the complexity in equipment and operation. A number of factors are important in achieving a good combination of retention and transmission of components in the feed. Fouling is the limiting factor in all applications of membrane filtration of milk and whey. Irrespective of the use of fouling minimization techniques, regular cleaning of membranes with chemicals is unavoidable. The purpose of membrane cleaning is usually two fold: (1) to restore membrane flux and (2) to reduce the microbiological load of the system, so as to remove all pathogens and to ensure dairy product quality. Disinfection of membrane surfaces is essential for aseptic processing. The nature of the cleaning cycle is somewhat dependent on the nature of the fouling deposit. In general, membranes are cleaned daily, in a cycle that can take 2–3 h. All stages of cleaning are best conducted at minimal transmembrane pressures and maximum cross flow velocities. The main subject of this project is the investigation of the improvement of membrane filtration processes in dairy industry by application of ceramic membranes, particulary hollow fibre ceramic membranes. The investigation in this project will be carried out according to the following plan: – the application of hydrodynamic methods for flux enhancement of membrane filtration in dairying; – the investigation of the effect of module configurations (hollow fibre, tubular) and membrane type (ceramics) processing efficiency; – varying of process parameters which effect the flux efficiency; – the flux regeneration by minimizing the fouling effect by various techniques (chemical cleaning, ultrasound).
Project ID: 
5 406
Start date: 
Project Duration: 
Project costs: 
970 000.00€
Technological Area: 
Membrane / Filtration technology
Market Area: 
Other industrial equipment and machinery

Raising the productivity and competitiveness of European businesses through technology. Boosting national economies on the international market, and strengthening the basis for sustainable prosperity and employment.