A reactor and its internals used for the thermal processing of a liquid mixture. The reactor comprises plates and at least part of the surface of said plates is used to perform the thermal processing. The reactor and its internals are used for the thermal processing of various liquid mixtures containing organic compounds. The processes, for thermal processing the mixture comprising organic compounds, comprising the steps of feeding the reactor and its internals and being useful for treating wastes oils and/or for destroying hazardous and/or toxic products; and/or for reusing waste products in an environmentally acceptable form and/or way, and/or for cleaning contaminated soils or beaches, and/or cleaning tar pits, and/or use in coal-oil co-processing, and/or recovering oil from oil spills, and/or PCB free transformed oils. A process for fabricating the reactor and its internals is also proposed.