Abstract: The inventive acoustic centrifuge is used for filtering suspensions and comprises a rotor whose housing has an inlet port and an outlet port located in its opposite end plates in line with a rotor drive shaft. Mounted on the shaft inside the rotor housing is an acoustic transducer which is accommodated in a coaxial chamber and communicating with the outlet port. The side wall of this chamber forms a filtering partition. The emitting surface of an acoustic transducer faces the partition. The diameter of the outlet port is substantially larger than that of the inlet port, but is smaller than the diameter of the emitting surface.

Abstract: A method of producing phosphorus-containing fertilizers, wherein the phosphate raw stock is treated with a mineral acid selected from the group, consisting of phosphoric acid, sulphuric acid and a mixture of both. The thus-obtained suspension of the phosphorus-containing fertilizers is acted upon by acoustic vibrations at a frequency of from 500 to 20,000 Hz and a second energy density of from 0.5 to 5 W/cm.sup.2, whereupon the end product is isolated.