A comprehensive study of the reversed arc plasma enhanced CVD (RACVD) reactor utilizing an Ar + H-2 + CH4 plasma-creating mixture in the pressure range 1-100 Torr with a plasma flow direction opposite to the direction of the arc current was carried out. The reversed arc discharge has rising current-voltage characteristics showing voltage increasing with pressure and hydrogen concentration. The spectrum of the Ar-H-2-CH4 plasma column includes CH, C-2, and H-2 molecular bands, in addition to H-alpha, H-beta, H-gamma, and H-delta lines. The dissociation degree of H-2 was estimated from the intensity ratio I-H alpha/I-ArI of the H-alpha and ArI 750 nm lines using the optical actinometry method, yielding an average dissociation degree of hydrogen in the arc plasma of 15-20%. The average vibrational and rotational temperatures of CH radicals are T-v = T-r = 3000 K +/- 300 K. The dissociation degree of hydrogen in the reversed arc discharge was calculated by the advection-diffusion-reaction model and showed reasonably good agreement both with experimental findings and with LTE calculations. The high concentration of nascent hydrogen and hydrocarbon radicals in the reversed arc plasma and its uniform distribution across the arc column makes it suitable for diamond coatings. The results obtained on the interaction of reversed arc plasma with substrates suspended within the current-carrier arc plasma column were applied to the description of a dusty reversed arc plasma in fluidized bed reactors. It was found that the energy effectiveness of the treatment of nanoparticles in the RACVD fluidized bed reactor exceeds 90%.