液氦净化系统的过滤及反吹特性研究

Research on filtration and regeneration of liquid helium filtration and purification system

作为一种优良的超导与冷却介质,超高纯液氦在工业以及航空航天等领域中的应用相当广泛。金属丝网过滤器具有理想均匀的孔径分布和优异的流体渗透性能,可适用于高洁净度、高安全性的低温液体净化系统。通过搭建液氦过滤与净化系统实验台,研究了过滤精度为0.5μm的不锈钢丝网过滤器对液氦中固体氮颗粒的过滤特性,探讨了压降及过滤效率的变化规律,以及反吹过程中的升温趋势。结果表明,该过滤器能有效实现液氦的净化。

As a kind of excellent cryogen with superconductivity, liquid helium of high purity has been widely used in many fields, such as industry and aerospace. Metallic wire mesh filter has advantages of uniform pore size distribution and preferable permeability, and is suitable for purification of cryogenic liquid with high purity and security. In this paper, a filtration and purification test rig is constructed to research the performance of a stainless steel wire mesh filter with filtration degree of 0.5μm, evolution tendency of pressure drop and filtration efficiency during filtration, and temperature recovery during regeneration are analyzed when purifying solid nitrogen particles from liquid helium. From the results, it is found that this filter is highly effective, the filtration process can be divided into three stages, and the filter cake plays an important role in pressure drop and efficiency.