INFLUENCE OF FILTER AIDS CHARACTERISTICS ON PRECOAT FILTRATION OF WINE

摘要

The filter aids, especially the diatomites, are widely used in precoat filtration of wine. Nevertheless, their reuse or regeneration being impossible, they present an important source of pollution. According to the European directive, since July 2002, the disposal of the spent diatomites used in precoat filtration, as final waste, is not allowed. The present study aims to propose regenerable filter materials having less environmental impact. The new filtering particles must be inert regarding wine and have approximately the same performances and characteristics as classical filter aids. A database of particles of various sizes, natures and forms is established. These new particles have been characterized (particle size distribution, specific surface, permeability, turbidity removal efficiency, etc.). The wine quality being the most significant criteria regarding filtration performances, therefore sensorial and organoleptic analysis are carried out too. Finally, some filtration tests are performed on experimental pilot and the pressure drops across the filter cake are analyzed. In the frame of this study, several particles have been tested in precoat filtration. Many of them (celluloses, polyamides…) seem to be effective as filter aids and their organoleptic compatibilities are demonstrated. Moreover, some of them are able to be cleaned or upgraded.