Abstract In this work some possibilities to improve the conventional spray drying process using programming in Excel as a calculation tool have been presented. The program gives a simple description of the drying process using thermodynamic calculations of heat and mass balance. Using the program it is possible to reduce operating costs and to improve capacity per unit of drying equipment. The minimization of energy consumption during the drying operation can be achieved by recycling exhaust air. The maximum theoretical range of recirculation is 60%. The fuel oil saving rate depends linearly on the rate of recirculation, and the theoretical maximum fuel oil saving is approximately 14%. Ecological issues were also considered as well, since decreased fuel consumption lowers harmful gas emission to the environment. All necessary data are represented in the process flow sheet, which is used for a better understanding of the drying process optimisation.