The management of physics behind the processes enables to attack different problems which imply mass- energy balancing, convection-diffusion processes, transport phenomena, evolution of chemical species and blending / separation processes. Depending on the problem and the equipment under analysis, analytical, numerical or empirical models are used, with field or bibliographic validation. Among the typical problems we can find the following: heating / drying / cooling, separation or settling, industrial ventilation and HVAC, reactors, etc.