Application of Pinch Analysis to improve heat integration in a dairy industry in Southwestern Paraná

Thermal energy plays a key role in dairy processing, especially in pasteurization, concentration, and evaporation stages, where large heat loads are required for heating and cooling operations. The complex thermophysical behavior of milk, whose properties such as specific heat capacity (Cp) vary with composition and temperature, presents additional challenges for accurate heat recovery estimation. In this context, the present study applies Pinch Analysis to evaluate the potential of heat integration in a dairy plant located in southwestern Paraná, Brazil. The investigation involved mapping process streams and estimating the thermodynamic properties of milk and water at different stages of the production process. Experimental and literature-based correlations were used to determine Cp values and enthalpy changes for each stream. Using these data, a composite curve was constructed to identify the Pinch Point and the minimum temperature difference (ΔT_min) required for feasible heat recovery. The results indicate significant potential for thermal integration, particularly in the pasteurization and evaporation sections. The study highlights the relevance of thermophysical characterization for accurate process modeling and demonstrates the applicability of the Pinch Methodology as a tool for improving energy efficiency in dairy industries, where complex, non-ideal mixtures are involved.