Burner tube for submerged combustion evaporator - PTFE coated on inside wall with thinner layer on outside

摘要

A metal burner tube with hot gases inside and corrosive chemical liquid outside is protected by a layer of plastic, partic. PTFE, the thickness on the hot side being greater than that on the cool side of the wall. Used as the burner tube assembly of a submerged combustion concentrator used, e.g. for the concn. of H2SO4. This method of tube protection gives longer operating life with min. corrosion.