Development of Gas Purification Technology Based on Selective electron Attachment

Research Project

Project/Area Number	01890006
Research Category	Grant-in-Aid for Developmental Scientific Research
Allocation Type	Single-year Grants
Research Field	広領域
Research Institution	Kyoto University
Principal Investigator	OKAZAKI Morio Kyoto University, Faculty of Engineering, Professor, 工学部, 教授 (90025916)
Co-Investigator(Kenkyū-buntansha)	MIYAHARA Minoru Kyoto University, Faculty of Engineering, Research Associate, 工学部, 助手 (60200200)
Project Period (FY)	1989 – 1991
Project Status	Completed (Fiscal Year 1991)
Budget Amount *help	¥9,000,000 (Direct Cost: ¥9,000,000) Fiscal Year 1991: ¥500,000 (Direct Cost: ¥500,000) Fiscal Year 1990: ¥800,000 (Direct Cost: ¥800,000) Fiscal Year 1989: ¥7,700,000 (Direct Cost: ¥7,700,000)
Keywords	Electron attachment reaction / Corona discharge / Gas purification technology / Negative ion / Removal of sulfur compound / removal of oxygen / Removal of iodine / スィ-プアウト型反応器 / 負イオン生成 / スイ-プアウト型反応器 / 酸素 / ヨウ素 / 負イオン沈着 / 硫黄化合物
Research Abstract	Two different types of reactors are constructed for gas purification ; (1) Deposition type reactor and (2) Sweep-out type reactor. In the deposition type reactor, the negative ions produced by corona discharge deposit on the anode surface after they lose the electron there. The anode of the sweep-out type reactor is a porous cylinder made of sintered metal. Through this cylinder a certain amount of gas is swept out to remove the gas with high concentration of electrophilic component from the anode. The following results on the removal of sulfur compound, oxygen and iodine were obtained. 1. Deposition type reactor Hydrogen sulfide, dimethyl sulfide, methyl mercaptan, sulfur dioxide, carbonyl sulfide and carbon disulfide can be removed in the deposition type reactor, and the influence of discharge current, inlet concentration and gas flow rate on the removal ratio can be explained using the proposed simulation model. When oxygen coexists, the removal ratio of sulfur compounds becomes high and reaction by-products are produced. The by-products can be neglected as the discharge current becomes large. The sulfur deposited on the anode surface was observed by an electron probe micro-analysis (EPMA). 2. Sweep-out type reactor Oxygen and iodine can be removed by the sweep-out type reactor, and the removal ratio can be simulated using the proposed model. The simulated results show that the removal ratio depends on the reactor shape and the larger radius of reactor gives a better removal ratio under a given reactor volume. The optimum operating conditions are determined from the balance of inlet concentration, gas flow rate, rate constant of electron attachment and deposition probability of negative ions on the anode surface.