Steam removal apparatus for discharge stack

[57] ABSTRACT

Portions of metal members having high thermal conductivity extend inwardly of a stack with other portions thereof extending outwardly of stack and out of contact with steam and other gaseous products conveyed by the stack reducing temperature of the inwardly extending portions by conduction of heat to other portions. Collector means receives water condensed onto the inwardly extending portions and discharge means removes water from the collector means.

Claims, 4 Drawing Figures

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Patented Aug. 14, 1973

3,751,884

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3,751,884

STEAM REMOVAL APPARATUS FOR DISCHARGE STACK

BACKGROUND OF THE INVENTION

This invention relates to steam removal apparatus for a discharge stack and more particularly to the removal of steam from a discharge stack carrying steam and other gaseous products.

As is well known in the art to which my invention relates, difficulties have been encounteed in removing steam from furnace discharge stacks, such as cupolas using air pollution control systems. That is, while effective means has been devised for removing solid particles from a gaseous stream, no satisfactory method has been proposed for continuously removing steam from a moving stream comprising steam and other gaseous products.

BRIEF SUMMARY OF THE INVENTION

In accordance with my present invention, I remove steam continuously from the discharge stack by providing metal members having high thermal conductivity and support such metal members from the stack with one portion thereof extending inwardly of the stack in position to be contacted by the steam and other gaseous products and with another portion thereof extending outwardly of the stack and out of contact with the steam and other gaseous products. The temperature of the portion extending inwardly of the stack is reduced by conduction of heat to the other portion of the metal member which extends outwardly of the stack whereby steam is condensed into water onto the portion which extends inwardly of the stack. Collector means within the stack receives the water condensed onto the inwardly extending portions and discharge means removes water from the collector means.

Apparatus embodying features of my invention is illustrated in the accompanying drawing, forming a part of this application, in which:

FIG. 1 is a top plan view showing my improved apparatus associated with a discharge stack;

FIG. 2 is a vertical sectional view taken generally along the line 2—2 of FIG. 1;

FI0. 3 is a top plan view showing a modified form of my invention; and,

FIG. 4 is a view taken generally along the line 4—4 of FIG. 3.

Referring now to the drawing for a better understanding of my invention, I show a discharge stack 10, which may be a discharge stack for an air pollution control system of a furnace, such as a cupola. As shwon in FIG. 2, openings 11 are provided in the sides of the discharge stack 10 for receiving elongated metal members 12 having high thermal conductivity, such as aluminum rods. Mounted between each metal member 12 and the opening 11 in the discharge stack 10 is an annular member 13 formed of an insulation material whereby the members 12 are insulated from the stack 11, thus reducing the transfer of heat from the stack 10 to the metal members 12.

The inner ends 14 of the metal members 12 extend upwardly and inwardly from the inner sides of the stack 10 and the inwardly extending ends 14 may be spaced angularly from each other and spaced vertically from each other, as shown. That is, ample space is provided between the upwardly and inwardly extending ends 14 to permit free passage of the steam and other gaseous products from the stack 10. The other ends of the metal members 12, indicated at 16, extend outwardly of the discharge stack 10 and out of contact with the upwardly moving stream of steam and other gaseous products. Accordingly, the outwardly projecting end portions 16 reduce the temperature of the upwardly and inwardly projecting ends 14 by conduction of heat away from the end portions 14 whereby steam is condensed into water onto the inwardly extending ends 14, as indicated at 17. The condensed water then flows down the sloping end portions 14 of the metal members 12 toward the inner sides of the discharge stack 10.

To remove the condensed water from the discharge stack 10, an annular collector ring 18 is mounted adjacent the inner surface of the discharge stack 10 at an elevation below the metal members 12 whereby the water of condensation flows into the collector ring 18, as sown in FIG. 2. Preferably, the collector ring 18 is provided with a horizontal flange 19 and a vertical flange 21 whereby it defines with the inner surface of the stack 10 an annular groove which extends all the way around the inner surface of the discharge stack 10. Communicating with the collector ring 18 through an opening 22 in the stack 10 is a discharge conduit 23 which removes the collected water from the ring 18.

From the foregoing description, the operation of my improved apparatus shown in FIGS. 1 and 2 will be readily understood. With the metal members 12 thus installed on the discharge stack 10, the steam and other gaseous products engage the inwardly extending ends 14 of the metal members 12 as they flow upwardly toward the discharge end of the stack 10. As the steam and gaseous products engage the cool end portions 14 of the metal members 12, the steam is condensed into water 17 onto the end portions 14 whereupon the water then flows down the inclined end portions 14 to the adjacent inner sides of the stack 10 whereupon the water then flows down the inner surface of the stack 10 into the collector ring 18. The water is then removed through the discharge conduit 23.

In FIGS. 3 and 4 of the drawing, I show a modified form of my invention in which radially extending metal members 12α extend through the insulation members 13 mounted in the openings 11 provided in the discharge stack 10. The inner ends of the metal members 12α, indicated at 14α converge toward the center of the discharge stack 10, as clearly shown in FIG. 3. Also, the inner ends 14α extend upwardly and inwardly of the stack 10, as shown in FIG. 4, whereby the water 17 condensed onto the inwardly extending end portions 14α flows downwardly toward the adjacent inner sides of the stack 10 and is finally collected in the collector ring 18 described hereinabove. The other ends of the metal members 12α, indicated at 16α, extend outwardly of the discharge stack 10 and out of contact with the upwardly removing stream of steam and other gaseous products flowing through the stack 10. Accordingly, the end portions 16α bring about a reduction in the temperature of the end portions 14α due to the conduction of heat by the outwardly projecting end portions 16α. The Water collected in the collector ring 18 is removed by the conduit 23, as described hereinabove relative to the apparatus shown in FIGS. 1 and 2.

From the foregoing, it will be seen that I have devised an improved system for rembving steam from a discharge stack carrying steam and other gaseous products. The metal members 12 are formed of a high ther3,751,884 mal conductivity metal, such as aluminum whereby there is a rapid transfer of heat from the inwardly projecting ends which extend inwardly of the stack to the outwardly projecting ends positioned outwardly of the stack. Accordingly, no elaborate cooling system is required for maintaining the inwardly projecting ends of the metal members at a proper temperature to change the steam into water as the staem passes the inwardly projecting ends of the metal members. Also, by providing an annular collector ring adjacent the inner surface of the stack in position to continuously receive the condensed water, the water is continuously removed by the discharge conduit to a loction outwardly of the discharge stack. Furthermore, by providing a system for removing steam from the discharge stack which does not require complicated equipment, I not only reduce the cost of installation but greatly reduce the maintenance costs after the system is put into operation.

While I have shown my invention in but two forms, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications without departing from the spirit thereof.