Patent ID: 7370847

Claim:
A grid plate bubble cap assembly for use in a reactor vessel and adapted for producing small gaseous bubbles above a grid plate in a reactor vessel, comprising: a grid plate; a bubble cap housing having a closed top, an open bottom, and an interior space defined by an inner wall of said bubble cap housing for dispersing vapor and liquid above said grid plate in a reactor vessel; and a shell-in-shell conduit assembly, extending at least partially through said interior space, for receiving vapor and liquid from below said grid plate when in use in a reactor vessel and feeding it to said interior space of said bubble cap housing, said shell-in-shell conduit assembly comprising: an inner pipe having an upper portion extending at least partially through said interior space and a bottom portion extending below said bubble cap housing and below said grid plate through which liquid and/or vapor saturated liquid can be fed from below said grid plate when in use in a reactor vessel to said interior space of said bubble cap housing; and an outer pipe disposed around a portion of said inner pipe and having an upper portion extending partially through said interior space, a lower portion extending below said bubble cap housing and through said grid plate, and a bottom end that terminates above a bottom end of said inner pipe so as to form a shell-in-shell space through said grid plate through which vapor can be directly fed from below said grid plate when in use in a reactor vessel to said interior space of said bubble cap housing.