GB751131A - Improvements in and relating to a tubular oil heater - Google Patents

Abstract

<PICT:0751131/III/1> <PICT:0751131/III/2> In a tubular furnace for heating hydrocarbon oils the side walls of the combustion chamber 10 are composed of a number of sloping faces 14 arranged in steplike formation; and sets of burners 18 are disposed along the steps 12, the burners being directed so that the flames therefrom sweep over the sloping faces. The hydrocarbon oil flows through horizontal tubes 30 connected in series and mounted between, and parallel to, the side walls so that they are heated by thermal radiation therefrom. The firing of each burner is adjustable independently of the others. If the burners are all fired at the same rate, the furnace walls as a whole can be very uniformly heated. On the other hand, by altering the firing rate of any set of burners, or the firing rate of individual burners in any set, differing parts of the walls of the furnace can be heated to different temperatures, and thus the rate of supply of heat to different sections of the tubes can be controlled. In the embodiment shown, the hydrocarbon oil flows in two separate streams through the furnace, each stream flowing through a bank of tubes 28 arranged in the combustion gas outlet 26 before it enters the tubes 30 in the combustion chamber. The tubes may, if desired, be arranged vertically. An embodiment is also described wherein the sloping faces of the combustion chamber slope inwards downwardly, the burners direct their flames downwards, and provision is made so that part of the hydrocarbon oil may be subjected to radiant heating only.