Heat exchanger with reduced fouling

#1. Field of the Invention

#The present invention relates generally to heat exchangers and more particularly to design aspects of heat exchanger components.

#2. Background of the Invention

#FIG. 1 is a side elevation cutaway view of a single-tube-pass heat exchanger having a non-removable tube bundle and representing a first embodiment of the present invention; and

#FIG. 2 is a side elevation cutaway view of a two-tube-pass heat exchanger having a removable tube bundle and representing a second embodiment of the present invention;

#FIG. 1 illustrates a heat exchanger 100 constructed according to the teachings of the present invention. In the figure, the shell portion is broken away to more clearly illustrate the tube bundle construction. While FIG. 1 shows a shell-and-tube exchanger in the form of a single-pass embodiment, the teachings of the present invention are equally applicable to many other forms of shell-and-tube exchangers such as, for example, multi-pass and U-shaped implementations. The heat exchanger 100 of the present invention includes a shell 150 and a tube bundle 160 contained therein.

#In a preferred embodiment, tube bundle 160 includes a pair of tubesheets 180 and 190 located, respectively, at each end of the tube bundle 160. The tubes contained in tube bundle 160 are fastened to apertures contained within tubesheets 180 and 190 by means known in the art such as by welding or by expanding the tubes into tubesheets 180 and 190. Tube side inlet 140 and corresponding tube side outlet 130 provide a means for introducing a first fluid into the tubes in tube bundle 160, and for expelling the first fluid from exchanger 100, respectively. Shell side inlet 110 and shell side outlet 120 provide a means for a second fluid to enter and exit the shell side of heat exchanger 100, respectively, and thus pass over the outside of the tubes comprising tube bundle 160.

#Preferably, the tubes in tube bundle 160 are supported by the novel coil structure which is disclosed in the assignee's co-pending patent application entitled “Heat Exchanger Flow Through Tube Supports” and which eliminates the need for baffles and allows for high-velocity fluid flow. Alternatively, the tubes in tube bundle 160 may be supported by conventional means such as by “rod baffles”, “twisted tubes” or “egg crate” style tube supports. Segmental baffles are not preferable according to the teachings of the present invention because they generally do not allow high-velocity fluid flow and they further create dead zones.