Unlike most works in the literature that propose the optimization of benchmark problems or very simple real structures, with idealized loads and restrictions, this work proposes a complete methodology to optimize real support structures of belt conveyor lines, considering realistic loads and restrictions imposed by international technical codes. Thus, the present work proposes a comprehensive methodology to minimize the mass of realistic steel structural systems composed of columns and galleries to support solid bulk conveyors. The objective is to obtain the minimum mass for different interactions between gallery spans and column heights for conveyors, taking into account the optimization of size, shape, and topology of each structural subsystem (columns and galleries) and thus obtaining the mass per unit of length of the conveyor line. For this, recurrent steel support structures are identified, analyzed, and selected according to their performance and, structurally resisting the applied load inputs, they are designed to minimize the structural system mass. The Enhanced Particle Swarm Optimization (EPSO) algorithm is used considering multiple constraints involving stress, displacement, buckling, frequency, and acceleration limits according to various international codes. An example of a realistic conveyor line is presented, in which 42 different interactions among the dimensions of the subsystems are simulated and the minimum mass of the system is obtained for each one of them. Thus, the results obtained allow, from the knowledge of the geometrical characteristics of the span and height of the system, to identify the optimized linear mass for any situation within the study boundary, resulting in an important practical contribution. Additionally, the graphs presented allow the designer to choose optimized solutions in terms of cost and raw material consumption for real-field applications. It was possible to determine that appropriate choices represent up to 35% mass reduction of structural systems.