| 摘要 |
<p>PURPOSE:To concentrate N2 to a purity held within a fixed range with reduced power consumption by sensing the purity of produced gaseous N2 basing on the change of flow rate of used N2 and adjusting automatically the switching period of each stage of the adsorption column basing on the signal of the sensed purity. CONSTITUTION:In a N2 concentration device utilizing generally used pressure swing adsorption (PSA) mechanism, a novel sequencer 52 is installed anew in place of conventionally used sequencer 20, and an output signal distribution 51 for an oxygen densitometer 19 is provided.A program of a sequence which prolongs or shortens the switching period of adsorption columns 21, 22 corresponding to the deviation of oxygen concentration when a deviation from target concn. is caused, to within 1-3min, is built-in the sequencer 52, and automatic valves 31, 32, 33, 34, 35, 36 are operated. On one hand, a compressed gas duct 13 is guided from a produced N2 tank 16 and connected to an unloader of an air compressor 11. The pressure in the produced N2 tank is adjusted to be held at a fixed pressure. For example, if the pressure of the produced N2 tank reachs 4.3kg/cm<2>.G, it is restored to 4.0kg/cm<2>.G by the operation of the unloader.</p> |
