Introduction:
Kedem-Katchalsky thermodynamic formalism (K-K) and Peusner network thermodynamics (PNT) belong to the basic research tools of membrane transport. The production of S-entropy, specifying the rate of change of entropy of the membrane system, is one of the basic values for assessing the irreversibility of mass, energy and momentum transport processes. It is a measure S-entropy intensity.

Material and methods:
A bacterial cellulose membrane (Biofill) with known transport parameters (Lp, σ, ω), for aqueous solutions of glucose was the subject of research. The research methods were K-K and PNT formalisms for binary non-electrolyte solutions.

Results:
On the basis of Onsager linear non-equilibrium thermodynamics and Peusner network thermodynamics, the S-entropy intensity of the membrane was described for non-electrolyte solutions. In this membrane system volume (Jv*) and diffusion (Js*) fluxes are generated by osmotic (Δπ/ ) and hydrostatic (ΔP) forces. The formulas describing the intensity of the S-entropy source for concentration polarization conditions θ*(S) and for solution homogeneity conditions – by θ(S) were derived. In order to show how concentration polarization influences S-entropy intensity, coefficient χ =θ*(S)/θ(S) was calculated. The results of numerical calculations of dependencies θ*(S)=f(∆P,△π/Cśr), θ (S)=f(∆P,△π/Cśr) and χ = f(∆P,△π/Cśr), calculated on the basis of the received mathematical equations by means of Mathcad Prime 3.0, are illustrated graphically in the form of va-rious types of curved surfaces.

Conclusions:
The concentration polarization of the membrane significantly influences the production of entropy in the membrane system by reducing it. For membranes with larger transport coefficient values, entropy production in the membrane system is greater. The influence of concentration polarization on the membrane system is greater for greater ∆P values.