Current activities for commercialization of oxyfuel power plant

Abstract

While the efforts to control global warming are being strengthened all over the world, expectations for CO₂ Capture, Utilization and Storage (CCUS) technology for coal fired power plants are increasing. IHI has been working on development of oxyfuel-combustion technology since 1989 with the aim of easily capturing and storage CO₂ emitted from coal fired power plants. For the demonstration of oxyfuel-combustion technology, IHI participated in the Callide Oxyfuel Project with collaboration between Australian and Japanese under the financial support of Australian, Queensland state and Japanese governments. In the project, the oxyfuel-combustion process was applied to the existing coal power plant in Queensland, Australia, and demonstration was carried out and successfully completed without any significant technical barrier to commercialization in March, 2015. In Oxyfuel-combustion, the coal-fired boiler is operated with an inlet O₂ content of 27 vol% in order to achieve the same furnace heat transfer as in conventional air-firing. The first outcome of oxyfuel-combustion is a significant reduction in NOx production, typically 60% reduction, measured in mgNOx/MJcoal. The second outcome of oxyfuel-combustion is a reduction in the actual volumetric flow of flue gas, typically a 60% to 70% reduction in gas flow measured as m³/h, and a proportionate increase in the CO₂ content of the flue gas from ~ 15 vol% (dry) in airfiring mode to 70 to 80 vol% (dry) in Oxyfuel mode. In addition, CO₂ product from the Callide Oxyfuel Project was injected into the Paaratte formation in the Otway Basin (Victoria) to investigate the geochemical effects of CO₂ (normal product) and CO₂ with added impurities. The recent research and development about characteristics of roller mill and electrical precipitator using combustion test facilities for the flexibility of plant design and the current commercialization activities of oxyfuel power plant are introduced in this paper.