In the following paper we present the mathematical description of the volume flow (J(v)) of aqueous solution of ethyl alcohol and glucose transported through a membrane. We consider three cases of the transport: the flow generated by the hydrostatic pressure difference Delta p, the osmotic pressure difference Delta Pi or by the simultaneous action of these two thermodynamical drives. The membrane transport is discussed within the frame of the Kedem-Katchalsky (K-K) equations, commonly used in the literature of this field. We present results obtained for the membrane filtration coefficient (L-p) in case of ethanol transport. This coefficient has been calculated based on the formula that accounts for the membrane properties, as well as the properties of the flowing liquid, namely the density and the viscosity of ethanol. The calculations of the volume flow (J(v)) of the solution have been based on the original form of the K-K equations in the case when the solutions at both sides of the membrane are mechanically stirred. (C) 2011 Elsevier B.V. All rights reserved.