US Patent 11707771 Cleaning process for a powder transfer system

A method of cleaning a complex powder transfer system including providing a powder transfer system having a washing fluid source, a spray device valve in fluid communication with the washing fluid source, a backflush valve in fluid communication with the washing fluid source, a receiving device having an upper chamber, a lower chamber, and a membrane filter disposed between the upper and lower chambers. The method includes opening the backflush valve to initiate a backflush cycle, running the backflush cycle to wash the upper chamber with a fluid, and closing the backflush valve after the backflush cycle completes. The method includes opening the spray device valve to initiate a spray device cycle, running the spray device cycle to wash the lower chamber with fluid, and closing the spray device valve after the spray device cycle completes. The method includes opening a pressure valve to provide PCA to the receiving container.