KINETICS OF GRINDING OF VEGETABLE RAW MATERIALS DURING ELECTRIC DISCHARGE EXTRACTION

Abstract

The influence of the degree of grinding of the particles of growing raw materials during electric discharge extraction on the quality of the obtained extracts was studied. Each discharge during electro-discharge extraction contributes to the grinding of a part of the raw material, which is confirmed by granulometric analysis. The particle size of the raw material should be controlled, since excessive grinding of the extracts results in cloudy, difficult to clarify and poorly filtered. The design of the extraction chamber is proposed, in which the grounded electrode is made in the form of a perforated plate, called a false bottom, with the optimal size of the holes and their density, which eliminates the over-grinding of the raw material particles, which leads to the production of turbid and difficult-to-filter extracts. Since the extraction of raw materials is carried out at a certain ratio of solid-liquid phases, the volume of the chamber from the sieve to the bottom does not significantly affect the kinetics of the extraction process itself, since it is intended for collecting the smallest particles of processed raw materials, the mass of which does not exceed 15-16% of the loaded mass of raw materials. The device of the extraction chamber, due to the high turbulence and intensive mixing of the suspension under the action of cavitation and shock waves initiated by the discharge in the liquid, allows you to remove small particles of raw materials less than 1 mm in size from the working area of the chamber. The results of the study show that the extraction of target components from various raw materials using a chamber with a false bottom can significantly reduce the content of the smallest particles of raw materials in the extract. It facilitates the filtration of the extract, reduces the filtration time, significantly reduces the likelihood of turbidity of the solution due to suspension, which improves the quality of the extract. Experimental studies of the developed electric discharge chamber with a false bottom, conducted with various types of plant raw materials, confirm the effectiveness of extraction in the chamber of the proposed design.