CAEP FEL-THz 2K低温系统氦气循环利用研究

Study on helium recycle of 2K cryogenic system for CAEP FEL-THz

中国工程物理研究院(CAEP)2K低温系统中,要对低纯度氦气进行回收和除杂。基于高压低温冷凝和吸附的方法,建成了一套氦气回收与纯化循环利用装置,单次回收低纯度氦气量为20Nm^3,低纯度氦气储存能力为1000Nm^3,纯化能力为20Nm^3/h,高纯氦气储存能力为3000Nm^3,能将粗氦气纯度从98%提升至优于99.9995%。实际运行表明,处理后的氦气纯度满足低温系统要求,较好地实现了氦气循环再利用,降低了系统对外部氦源补充的依赖。

The low purity helium must be recovered and impurities must be removed in the 2 K cryogenic system at CAEP. Based on the method of condensation and adsorption under high pressure and low temperature, a helium recovery and purification recycle installation was established. 20 Nm^3 low purity helium could be recovered each time with a total storage of 1000 Nm^3. Meanwhile, the purification capacity was 20 Nm^3/h with a total storage of 3000 Nm^3 pure helium,and the purity of helium could be improved from 98% to higher than 99.9995%. The actual operation indicates that the purity of processed helium satisfies the cryogenic system, helium is well recycled and the dependence of cryogenic system on outside helium is reduced.