NOVELTY - Production of biodiesel from natural and recycled vegetable oils, involves: (a) conditioning of the oil used by passing same through a filter press and subsequent heating; (b) conditioning of the reagents in a tank provided with a bladed stirring system; (c) esterification in two reactors designed so as to maximize the degree of mixing of the reagents inside the reactor; (d) transesterification by alkaline catalysis such that the triglycerides present in the oil transesterify with methanol; (e) decanting; (f) distillation; and (g) washing and centrifuging.    USE - The method is useful for the production of biodiesel from natural and recycled vegetable oils (claimed).    ADVANTAGE - The method enhances production of biodiesel from natural and recycled vegetable oils, and increases overall process efficiency and reduces environmental impact. Also, the method reduces manufacturing costs, and environmental impact associated with the process by reduce consumption and carbon footprint corresponding to the use of glycerol and methanol.    DETAILED DESCRIPTION - Production of biodiesel from natural and recycled vegetable oils, involves: (a) conditioning of used oil: the oil is passed through a filter press in order to filter the impurities that it may contain, then heating to a temperature of 85 degrees C using a tank provided with a polyurethane insulating bedroom and an internal coil arranged horizontally acting as heat exchanger; (b) conditioning of the reagents: in a tank provided with a bladed stirring system, mixing methanol and sulfuric acid in a proportion which will depend on the amount of free fatty acids in the used oil even in the vicinity of 6 moles of methanol per mole of oil and 1 wt.% of sulfuric acid based on the weight of oil; (c) esterification: after measurement of the composition of free fatty acids (FFA) in the event that the oil has an acid index above 2.5% it is necessary to carry out an esterification process; for this, the oil and the reactants are mixed by using a turbine, passing then through two esterification reactors; the esterification reactors have a piston, a coil and perforated inner rings arranged at different heights transversely and evenly distributed; the working temperature is 60 degrees C, which is maintained by the vertical coil, through which hot water circulates; each reactor is operated by an ideal plug flow model, with a residence time of 20 minutes; the piston while stirring and mixing reaction mass makes collision with the rings there within the reactor thus lowering the interfacial surface between the reactants and increase reaction rate, leading to a more uniform product and in less time than traditional systems using reactors with ideal thorough mixing models; where the reaction that occurs inside the system is represented by Reaction Scheme (I); (d) transesterification: using alkaline catalysis such that the triglycerides present in the oil transesterify with methanol; the optimum working conditions are: temperature between 60 and 65 degrees C, sodium hydroxide (NaOH) as the basic catalyst in a proportion of between 1 and 2 wt.% by weight of the oil content and molar ratio or number of moles of alcohol divided by the number of moles triglyceride, between 6/1 and 20/1, where the reaction is represented by Reaction Scheme (II); at this stage the product from the esterification reaction mixture is neutralized with sodium methoxide and from a storage tank containing sodium hydroxide and methanol; methoxide is added in a molar ratio of 6/1 and 1 wt.% of NaOH; for this, the mixing vessel contains a stirring blade system to take care of mixing and neutralizing the esterified oil product from the esterification stage; this step is carried out from two transesterification reactors; the two reactors are maintained at a temperature of 60 degrees C, with a vertical coil placed along the reactor by which water will be circulated at that temperature; the reactor is operated by the ideal plug flow model, with a residence time of 20 minutes; each reactor is provided with a piston at the bottom, so that the piston while stirring and mixing causes reaction mass shock on the rings that are inside the reactor, thus lowering the interface between the reagents and increase the reaction rate yielding a more uniform product than traditional systems using reactors with ideal thorough mixing models; the reactors are insulated with a bedroom injected with polyurethane so as to achieve a stable temperature inside the reactors and avoid energy losses; (e) decanting: after the mixing process resulting from transesterification, the two phases formed will be separated where the upper phase is the methyl esters, with some methanol and impurities, and lower phase is glycerin with methanol, unreacted and impurities; at this stage it will work in batch, so you have two decanters, not to interrupt the continuous process of the previous stages; (f) distillation: after decantation of each of the two phase, vacuum distillation process for the recovery of alcohol; and (g) washing and centrifugation: at this stage, purifying the crude biodiesel, separating the impurities that accompany it; for this, the biodiesel obtained with a pressure washer to remove the soapy wash part, thus the biodiesel from distillers still dragging some glycerine is passed through a centrifuge which will remove as much glycerin soaps formed, thus obtaining biodiesel in perfect condition for marketing, while glycerin generated on the one hand will be used for the production of additives for biofuel, or is purified and sold as pure glycerin, while process water is reused once it has been properly treated...