After introductory considerations the second chapter of this dissertation deals with the complex theoretical background of hydrodynamic cavitation. Then the basics of studying the dynamics of bubbles or cavities in hydrodynamic cavitation are presented. The basic expression for describing the dynamics of bubbles or cavities, being Plasset-Rayleigh model, is derived. The basic effects of cavitation are described, and expressions for calculating the changed energy during the collapse of bubbles or cavities are defined. The parametric analysis identifies two groups of cavitation parameters, and these are the parameters of pressure and time interval. A comparison with acoustic cavitation is made, and similarities and differences are defined. The second chapter concludes with the presentation of different mathematical models of hydrodynamic cavitation, from relatively simple to complex, showing the results of simulations, in particular of the obtained correlation expressions that clearly define the basic construction characteristics of hydrodynamic cavitators. The third chapter deals with the conventional production process of biodiesel. The basics of this process are given, and all aspects of the entire biodiesel production process from processed vegetable oils with possible alternatives are given consideration to. The third chapter concludes with a review of new reactor constructions for the intensification of the transesterification process. The aim of this review is to compare different techniques and technologies for biodiesel production, which have potential applications in the conventional process, but also in future alternative production processes. The fourth chapter gives an overview of the use of new technologies and chemical reactions in the production of biodiesel. An extensive analysis of technical and scientific literature leads to the conclusion that the research of new processes for biodiesel production in recent years has been directed toward the following goals: •use of cheaper raw materials for biodiesel production, which typically have high portions of free fatty acids (non-conventional raw materials for biodiesel production), •use of new chemical reactions in the production of biodiesel from non-conventional raw materials and / or use of chemical reactions where glycerol is not a byproduct and •implementation of new technologies to intensify chemical reactions that are used in biodiesel production from existing and / or new raw materials. These trends in research into new methods of biodiesel production are included in the problems that are dealt with in this dissertation. The possible use of technical fatty acids as a raw material for biodiesel production is examined. Technical fatty acids are a byproduct of the refining process or neutralization of edible vegetable oils, and are characterized by a high portion of free fatty acids, typically from 50% to 75%, and low cost compared with the price of processed (refined) oil. Free fatty acids contained in technical fatty acids are converted into methyl esters of fatty acids, or biodiesel through the chemical reaction of esterification of free fatty acids with methanol and sulfuric acid as catalyst. It has been suggested to use methyl acetate in the esterification reaction, which would reduce the problem of formation of water as the product of a chemical reaction. It has been suggested that the process of biodiesel production in the second stage of processing, where the remaining triglycerides are converted into methyl ester of fatty acids biodiesel, is implemented using the reaction of triglycerides with acetic acid, together with sulfuric acid as a catalyst where triacetin is formed instead of glycerol. The fourth chapter concludes with an analysis of alternative chemical reactions in the production of biodiesel, and these are esterification of free fatty acids, glycerolysis of free fatty acids and triglyceride hydrolysis. After defining the hypothesis of the dissertation in the fifth chapter, the sixth chapter describes the construction of experimental facilities, and a description of experiments is given. The essential elements are the selection of the design characteristics of the cavitation orifice plate on the basis of the extensive theoretical analysis of the hydrodynamic cavitation process, and the experimental determination of the operating parameters that enable the intensification of the esterification process of free fatty acids. Some factors influencing the esterification process of free fatty acids, such as catalyst concentration and methanol portion, have been experimentally tested. The analysis of the results of experiments are carried out in the seventh chapter, while the conclusions and directions for further research are presented in the eighth chapter.