圧力スウィング吸着法(PSA)を用いたガス濃縮器では, ゼオライトなどのガス吸着層に水分が吸着することによってガス吸着性能が大幅に低下する。本研究では, 筒内水分量の短時間・空間分布計測が可能となり, 吸着性能の劣化を時系列的に評価することを目的とする。PSA操作時の小型NMRコイルによるゼオライト吸着筒内の水分分布の時系列計測を行うために, 複数の小型NMRコイルを吸着筒内に挿入し, 多点のNMR信号を同時に計測できるシステムを構築した。上記の実験結果を理論と比較して検討するために数値解析を行った。この解析によりゼオライト充てん層内の酸素・窒素濃度, ガス流速, ガス温度, ゼオライト温度を算出した。
Some gas concentrators work with a "pressure swing adsorption process." If water vapor absorbs to the gas adsorption column which packed zeolite, the gas adsorption performance will fall substantially. In this research, a small NMR coil is inserted into gas adsorption column. Using small coil can measure spatial water distribution for a short time quantity. Four small NMR coils were inserted in the filling layer, and the NMR signal was acquired. When the small NMR coil was used, it turned out that the low amount of moisture of 0.5 - 1 wt% is also quantitatively measurable. In order to analyze gas flow, oxygen concentration and temperature fields of the gas and zeolite in two zeolite columns at an adsorption-type oxygen concentrator, theoretical analysis was conducted. Time-dependence changes of gas velocity, oxygen concentration, and gas and zeolite temperatures were analyzed numerically.
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