This work presents the phase transformations and movement dynamics in a case of complex transfer processes self-interaction on sprayed water droplets in biofuel furnace flue gases flow. The droplet phase transformation cycle is defined according to a numerical iterative scheme which is created by heat flow balance condition onto the droplet surface, where combined solutions for the tasks of external heat transfer and phase change as well as internal heat transfer in a droplet, are designed. The flue gases velocity, temperature and droplet dispersity are named as defining factors of droplets trace to full evaporation in flue gases at biofuel furnace. Relevant secondary factors are recognized as sprayed water temperature, initial velocity provided for droplets, humidity of flue gases and specifics of droplets heat transfer. It is based on, that boundary conditions, which ensures the fastest and the slowest water droplets evaporation, do not define the marginal trace of droplets till evaporation. In biofuel flue gases flow at droplet phase transformation regimes cycle two, practically equivalent periods are distinguished. In the first period significant is droplet growth due to influence of condensation, warming water expansion and droplets slipping decrease in flue gases. In the second period the trace of droplets is already defined by flue gases flow velocity. The combined droplet heating process is more significant for larger droplets, while for smaller than 70 mu m diameter droplets impact of thermal radiation is neglect. (C) 2018 Published by Elsevier Ltd.