Patent ID: 7449155

Claim:
A reactor cup riser for receiving and separating a liquid and vapor product stream in a reactor vessel to provide an essentially vapor-free liquid and/or solids free recycle stream, comprising: a shell-in-shell pipe assembly comprising an inner liquid/vapor feed pipe and an outer pipe disposed around a portion of said inner feed pipe, said inner pipe having a top end that terminates below an upper end of said outer pipe and an open bottom end extending below a bottom end of said outer pipe through which liquid and vapor can be received into said pipe assembly, said outer pipe having a vapor outlet conduit disposed at a top end through which separated vapor can exit said pipe assembly and a liquid exit opening at a bottom end through which separated liquid can exit said pipe assembly; a plurality of liquid/vapor exit passages disposed through a side of said inner pipe near said top end through which liquid and vapor can pass into a shell-in-shell space between said inner and outer pipes; and a helical liquid/vapor separator disposed in said shell-in-shell space in communication with said liquid/vapor exit passages for impinging liquid onto an inner wall surface of said outer pipe, wherein liquid separated from vapor by said separator is able to flow down through said shell-in-shell space between said inner and outer pipes toward said liquid exit opening, wherein vapor separated from liquid by said separator is able to pass up toward said vapor outlet conduit.