CATALYST OR SORBENT BEDS

摘要

A fixed bed containing a particulate catalyst or sorbent material (10) subje ct to operation at high temperature having a shaped boundary member (16) inclin ed to the direction of fluid flow through the bed that maintains the depth of said catalyst or sorbent at the boundary of the bed through a series of thermal expansion-thermal contraction cycles is described. By maintaining be d depth, the shaped boundary member (16) can prevent bypass of, e.g. ammonia through a bed of particulate ammonia oxidation catalyst.