Abstract: The invention relates to a method and apparatus for producing a feed mixture, advantageously suitable to an anaerobic bioreactor and containing liquid and solid materials, for the further treatment of waste materials. The method of the invention includes at least the following steps:a) into a feed mixture reactor (1), there is first fed liquid so that the free liquid surface (5) is located essentially above the solid material feed point (6) provided in the reactor (1),b) the solid waste material fed into the feed mixture reactor (1) is fed to below the free liquid surface (5) of the reactor (1), and from the solid waste material there is separated (10, 14) both light and heavy rejectable materials by utilizing an agitator (7) installed in the feed mixture reactor (1), and countercurrent washing (14) directed towards the bottom part of the reactor (1).

Abstract: A melt is passed as a flow into a space wherein the melt flow impinges against a deflecting surface transforming the melt flow into a thin, evenly spreaded film which, upon meeting one or more jets of a dispersing gaseous or liquid substance, is effectively dispersed.

Abstract: Materials dissolved in water are separated from each other by means of a cementation agent. The materials treated are those having a greater hydrogen overpotential than the potential difference between the cementation agent and hydrogen gas. A water solution of material to be cemented is fed upwards to a reaction zone through a bed containing the cementation agent, and agglomerates produced sink from the bed to be crushed in a zone below the bed.The addition of a flocculation agent to the reaction zone causes the material to cement as smooth-surfaced particles which do not adhere to each other or allow large gas bubbles to grow attached to the particles.