Lait 80 (2000) 5-14
Flat ceramic membranes for the treatment of dairy products: comparison with tubular ceramic membranes
André Grangeon, Philippe Lescoche
TAMI Industries, ZA les Laurons, 26110 Nyons, France
TAMI Industries has developed and commercialized since 1996 a new range of original ceramic membranes with a plane geometry. This type of membrane associates the interest of the weak hydraulic diameters to important values of thermal, mechanical and chemical resistance of ceramics. Shaped in a cassette form with open channels, these new membranes showed their efficiency in the environmental market. The purpose of this paper is to describe the standardization of milk proteins and the whey concentration studied to test these new products in the dairy industry. The result is expressed under the form of classic curves of the permeate flux in function of the VCF. These curves were established for velocities of 0.5 m.s-1, 1 m.s-1 and 2.5 m.s-1 and showed performances in the order magnitude of other types of membranes. By comparing with tubular products of TAMI industries, and on the basis of an industrial example (10 m3.h-1 of milk to process), two differences appeared: - on one hand, energy consumption by m3 of permeate product were respectively for the plane geometry and the tubular geometry of 6 kW.m-3 and 9.4 kW.m-3; - on the other hand the cost of the system was 12 to 14 kF.m-2 for the tubular geometry and 8 to 10 kF.m-2 for the plane geometry. These differences were the consequence of the reduction of the hydraulic diameter. If one takes into account the shear constraint on the wall and the circulation speed as important parameters for the crossflow filtration, one observes that the diminution of the hydraulic diameter allows: - at constant velocity, to increase the shear constraint and to reduce energy. - at constant shear constraint, to reduce both the circulation speed and energy. In this case, membrane performances were identical and the equipment pricing became cheaper by reduction of the engineering costs. These comparisons were established between tubes and cassettes with opened channels and showed the interest to reduce the hydraulic membrane diameter what can simply be done by using the plane geometry. The particular case of a spacer, as a mean to reduce the hydraulic diameter, was not considered because of the complexity of the flow. Choosing open channels ceramic membrane plates allowed a global reduction of investment and functioning costs while keeping the interest of ceramics.
ceramic membrane / plate / tubular / dairy
Correspondence and reprints: P. Lescoche
Copyright INRA, EDP Sciences