Plasma gasification reactor

A plasma gasification reactor vessel having a top section with a conical wall extending up from a bottom section, containing a carbonaceous bed into which plasma is injected by plasma torches, to a roof of the vessel is arranged in ways that can contribute to characteristics of gas flow and solids residence time that are favorable for thoroughness of reactions and yield of useful reactions products. In some cases, such a conical wall is combined in arrangements with other features such as one or more feed ports arranged to give more uniform distribution including examples with a feed port that has a distributive feed mechanism. The roof of the vessel, in some examples, has vertical outlet ports that include intrusions into the interior volume of the reactor proximate the conical wall of the top section. The configurations of outlet ports with intrusions and the configurations of feed ports for more uniform distribution of feed material are also applicable to reactor vessels with other geometries.