For the classification of the various biochar production methods, I consider that the concepts of the combustion, pyrolysis and gasification operations involved must be taken into consideration, which in one way or another lead to the quantity and quality of the product obtained. In this, the stoichiometric equations until reaching the Boudouar equation 2CO → CO2 + C, is the main aspect. This is achieved by controlling the reactions that take place during the decomposition of biomass into liquid and gaseous compounds, the reactions that take place between the solid, liquid and gaseous phases, the control of the temperature and the configuration of the fluid displacement zone. . In general; Pyrolysis is the thermal degradation of biomass in the absence of an oxidizing agent, it is a thermal transformation process in which it is possible to obtain solid, liquid or gaseous products and, on the other hand, it is the first step in the processes of gasification and combustion. With the configuration of the fluid displacement zone, the time factor necessary for the stoichiometry of the reactions is regulated.