FIELD: oil producing industry; pipeline transport. SUBSTANCE: according to invention, liquid in flow is subjected in turn first to acoustic excitation and then heat treatment by means of separate heating device, acoustic excitation being provided at one of the following resonance frequencies governed by common relationship F = F1N-1/2, where 104≥N≥1 is chosen whole number, F1 = 63,992420 [kHz] - is basic frequency at N=1. Proposed plant contains acoustic exciter unit and separate heating device whose input is connected with output of acoustic exciter unit, and output, with input of acoustic exciter through shutoff-and-regulating member. Acoustic exciter unit is made in form of rotor hydrodynamic exciter containing rotor with shaft resting on bearings and at least one working wheel fitted on shaft. Working wheel is made in form of disk with peripheral ring wall in which liquid outlet holes uniformly spaced over circumference are made. Exciter is provided also with stator with wall coaxial with working wheel, liquid outlet holes communicating with space of working wheel and liquid outlet hole, ring chamber formed by coaxial wall of stator and peripheral ring wall of working wheel and communicating with stator outlet hole, and rotor drive with designed speed of rotation. Value of outer radius of peripheral ring wall of working wheel is R = 2,8477729 n-2/3•104[mm], where n = 14,651908F3[rpm] - is working wheel speed, F = 63,992420N-1/2 [kHz] is basic frequency of resonance excitation, 104≥N≥1 - is chosen whole number , and value of inner radius of coaxial wall of stator is R1 = R+BS(2π)-1[mm], where B≥1 is chosen whole number, S=7.2973531 mm - pitch of working wheel outlet holes on circumference of radius R. EFFECT: improved efficiency of preliminary of liquid. 7 cl, 4 dwg
