Development of SO decomposer for thermochemical hydrogen production by IS process; Basic design of SiC plate-type SO decomposer and catalyst test results

Kanagawa, Akihiro; Imai, Yoshiyuki  ; Terada, Atsuhiko  ; Onuki, Kaoru; Hino, Ryutaro

Thermo-chemical Iodine-Sulfur (IS) process has a potential to produce large amount of hydrogen without CO emission by using thermal energy of a high temperature gas-cooled reactor (HTGR). In SO decomposer of IS process, SO gas is catalytically decomposed into O and SO under high temperature condition up to 850C using the sensible heat of He gas. The decomposer is exposed to the severe corrosive condition. We proposed a new concept of the decomposer, which featured a plate-type heat exchanger made of SiC ceramics and revealed the results of thermal-hydraulic and mechanical strength analysis. To examine the fabricability of the proposed concept, a mock-up model was test-fabricated and issues on the fabricability of large-sized decomposer were clarified. Also, preliminary catalyst tests were carried out to clarify catalyst bed specification of the SO decomposer.