Abstract: A hydrogen production system and a hydrogen production method include a heat exchanger that heats steam by using a heating medium heated by thermal energy at 600° C. or higher, a high-temperature steam electrolysis device that produces hydrogen by using the steam, and a heating device that heats the high-temperature steam electrolysis device by using the steam.

Abstract: A high-temperature steam electrolysis device, a hydrogen production method, and a hydrogen production system include: a high-temperature steam electrolysis cell having a cylindrical shape in which a hydrogen/steam gas diffusion electrode layer is disposed on an inner side of an electrolyte layer and an oxygen gas diffusion electrode layer is disposed on an outer side thereof; a steam flow channel in which high-temperature steam flows on an inner side of the high-temperature steam electrolysis cell; and a helium flow channel in which high-temperature helium flows to heat the high-temperature steam electrolysis cell on an outer side of the high-temperature steam electrolysis cell.

Abstract: A waste material treatment apparatus is provided which: supplies a reactant to facilitate a prompt reaction between an oxidation agent or a neutralizing agent and gases that contain chlorine, hydrocarbons, and the like, and that are emitted from non-plastic garbage present in waste materials when heated instantaneously; renders the non-plastic garbage harmless and reduced in volume without generating dioxins or carbon dioxide by repeating the instantaneous heating; and renders plastics harmless and cleaned, thereby enabling recycling thereof.