A rotating heat regenerator is used to recover heat from the syngas at it exits the reactor vessel of a waste or biomass gasifier. In some embodiments, three or more streams are passed through the heat exchanger. One stream is the dirty syngas, which heats the rotating material. A second stream is a cold stream that is heated as it passes through the material. A third stream is a cleaning stream, which serves to remove particulates that are collected on the rotating material as the dirty syngas passes through it. This apparatus can also be used as an auto-heat exchanger, or it can exchange heat between separate flows in the gasifier process. The apparatus can also be used to reduce the heating requirement for the thermal residence chamber (TRC) used downstream from the gasification system

A method of processing a material comprising: receiving an input material to be processed within a reaction chamber, the input material comprising a biosolids material; energizing one or more sets of electrodes, each set of electrodes including an anode electrode and a cathode electrode, each anode electrode and cathode electrode having an electrode tip exposed to the reaction chamber; and creating an electrical arc between the anode electrode tip and the cathode electrode tip within the reaction chamber to subject at least some of the input material to electrical arcing, thereby reacting at least a portion of the biosolids material and forming a processed material comprising hydrogen (H.sub.2) and carbon monoxide (CO).