A novel continuous microsphere separation process based on surrounding staggered flow

Abstract Microspheres are widely used in multiple fields, and their particle size and distribution are crucial for their application. At present, narrow particle size distribution microspheres suffer from complex separation processes, low screening efficiency, and lack of process flexibility. To address this issue, a novel surrounded staggered flow separation process for continuous separation of microspheres with different particle sizes has been proposed. First, surrounding staggered flow was constructed using a microscale helix for sieving microspheres, and the flow mechanism was analyzed. Then, the flow control parameters were adjusted to optimize the sieving process. In addition, the separation efficiency was increased from 59.2% to 88% by continuous separation of microspheres using a single helix. At the same time, microspheres with a smaller size span can be successfully obtained. This adjustable helix for continuous screening of microspheres is both simple and efficient, and is a very promising method and equipment for screening microspheres.