FIELD: dissolving processes. SUBSTANCE: method for humic acid producing includes coal treating with alkali solution, low frequency acoustic oscillations, and cavitation vibration jets in a device having a body, a fixture for inlet and outlet of interacting phases, working members vibration generator. The body is provided with circulation tube, a diaphragm, and a piston with a rod fixed on it. Loading member with flexible membrane is installed on top end of the rod. The rod passes through central holes in working members. The latter are made in the form of partitions with jet forming extensions installed through body height. For example, the extension may be made in the form of cylinder/cone holes directed alternatively up and down. Axes of the adjacent partitions are displaced relative to one another. Loading member is made in the form of cone with elastic membrane installed in its lower base. EFFECT: high efficiency. 3 cl, 3 dwg
